Commit Graph

1991 Commits

Author SHA1 Message Date
Mathieu Malaterre
d8731527ac powerpc/sparse: Fix plain integer as NULL pointer warning
Trivial fix to remove the following sparse warnings:

  arch/powerpc/kernel/module_32.c:112:74: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/module_32.c:117:74: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1155:28: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1230:20: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1385:36: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:1752:23: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2084:19: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2110:32: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2167:19: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:2183:19: warning: Using plain integer as NULL pointer
  drivers/macintosh/via-pmu.c:277:20: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:155:67: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:247:27: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:249:27: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/setup.c:252:37: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:127:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:148:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:44:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:57:21: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/tlb_hash32.c:87:21: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:160:31: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:167:22: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:274:21: warning: Using plain integer as NULL pointer
  arch/powerpc/kernel/btext.c:285:31: warning: Using plain integer as NULL pointer
  arch/powerpc/include/asm/hugetlb.h:204:16: warning: Using plain integer as NULL pointer
  arch/powerpc/mm/ppc_mmu_32.c:170:21: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/pci.c:1227:23: warning: Using plain integer as NULL pointer
  arch/powerpc/platforms/powermac/pci.c:65:24: warning: Using plain integer as NULL pointer

Also use `--fix` command line option from `script/checkpatch --strict` to
remove the following:

  CHECK: Comparison to NULL could be written "!dispDeviceBase"
  #72: FILE: arch/powerpc/kernel/btext.c:160:
  +	if (dispDeviceBase == NULL)

  CHECK: Comparison to NULL could be written "!vbase"
  #80: FILE: arch/powerpc/kernel/btext.c:167:
  +	if (vbase == NULL)

  CHECK: Comparison to NULL could be written "!base"
  #89: FILE: arch/powerpc/kernel/btext.c:274:
  +	if (base == NULL)

  CHECK: Comparison to NULL could be written "!dispDeviceBase"
  #98: FILE: arch/powerpc/kernel/btext.c:285:
  +	if (dispDeviceBase == NULL)

  CHECK: Comparison to NULL could be written "strstr"
  #117: FILE: arch/powerpc/kernel/module_32.c:117:
  +		if (strstr(secstrings + sechdrs[i].sh_name, ".debug") != NULL)

  CHECK: Comparison to NULL could be written "!Hash"
  #130: FILE: arch/powerpc/mm/ppc_mmu_32.c:170:
  +	if (Hash == NULL)

  CHECK: Comparison to NULL could be written "Hash"
  #143: FILE: arch/powerpc/mm/tlb_hash32.c:44:
  +	if (Hash != NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #152: FILE: arch/powerpc/mm/tlb_hash32.c:57:
  +	if (Hash == NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #161: FILE: arch/powerpc/mm/tlb_hash32.c:87:
  +	if (Hash == NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #170: FILE: arch/powerpc/mm/tlb_hash32.c:127:
  +	if (Hash == NULL) {

  CHECK: Comparison to NULL could be written "!Hash"
  #179: FILE: arch/powerpc/mm/tlb_hash32.c:148:
  +	if (Hash == NULL) {

  ERROR: space required after that ';' (ctx:VxV)
  #192: FILE: arch/powerpc/platforms/powermac/pci.c:65:
  +	for (; node != NULL;node = node->sibling) {

  CHECK: Comparison to NULL could be written "node"
  #192: FILE: arch/powerpc/platforms/powermac/pci.c:65:
  +	for (; node != NULL;node = node->sibling) {

  CHECK: Comparison to NULL could be written "!region"
  #201: FILE: arch/powerpc/platforms/powermac/pci.c:1227:
  +	if (region == NULL)

  CHECK: Comparison to NULL could be written "of_get_property"
  #214: FILE: arch/powerpc/platforms/powermac/setup.c:155:
  +		if (of_get_property(np, "cache-unified", NULL) != NULL && dc) {

  CHECK: Comparison to NULL could be written "!np"
  #223: FILE: arch/powerpc/platforms/powermac/setup.c:247:
  +		if (np == NULL)

  CHECK: Comparison to NULL could be written "np"
  #226: FILE: arch/powerpc/platforms/powermac/setup.c:249:
  +		if (np != NULL) {

  CHECK: Comparison to NULL could be written "l2cr"
  #230: FILE: arch/powerpc/platforms/powermac/setup.c:252:
  +			if (l2cr != NULL) {

  CHECK: Comparison to NULL could be written "via"
  #243: FILE: drivers/macintosh/via-pmu.c:277:
  +	if (via != NULL)

  CHECK: Comparison to NULL could be written "current_req"
  #252: FILE: drivers/macintosh/via-pmu.c:1155:
  +	if (current_req != NULL) {

  CHECK: Comparison to NULL could be written "!req"
  #261: FILE: drivers/macintosh/via-pmu.c:1230:
  +	if (req == NULL || pmu_state != idle

  CHECK: Comparison to NULL could be written "!req"
  #270: FILE: drivers/macintosh/via-pmu.c:1385:
  +			if (req == NULL) {

  CHECK: Comparison to NULL could be written "!pp"
  #288: FILE: drivers/macintosh/via-pmu.c:2084:
  +	if (pp == NULL)

  CHECK: Comparison to NULL could be written "!pp"
  #297: FILE: drivers/macintosh/via-pmu.c:2110:
  +	if (count < 1 || pp == NULL)

  CHECK: Comparison to NULL could be written "!pp"
  #306: FILE: drivers/macintosh/via-pmu.c:2167:
  +	if (pp == NULL)

  CHECK: Comparison to NULL could be written "pp"
  #315: FILE: drivers/macintosh/via-pmu.c:2183:
  +	if (pp != NULL) {

Link: https://github.com/linuxppc/linux/issues/37
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 12:04:38 +10:00
Christophe Leroy
0e36b0d125 powerpc/mm: Only read faulting instruction when necessary in do_page_fault()
Commit a7a9dcd882 ("powerpc: Avoid taking a data miss on every
userspace instruction miss") has shown that limiting the read of
faulting instruction to likely cases improves performance.

This patch goes further into this direction by limiting the read
of the faulting instruction to the only cases where it is likely
needed.

On an MPC885, with the same benchmark app as in the commit referred
above, we see a reduction of about 3900 dTLB misses (approx 3%):

Before the patch:
 Performance counter stats for './fault 500' (10 runs):

         683033312      cpu-cycles                                                    ( +-  0.03% )
            134538      dTLB-load-misses                                              ( +-  0.03% )
             46099      iTLB-load-misses                                              ( +-  0.02% )
             19681      faults                                                        ( +-  0.02% )

       5.389747878 seconds time elapsed                                          ( +-  0.06% )

With the patch:

 Performance counter stats for './fault 500' (10 runs):

         682112862      cpu-cycles                                                    ( +-  0.03% )
            130619      dTLB-load-misses                                              ( +-  0.03% )
             46073      iTLB-load-misses                                              ( +-  0.05% )
             19681      faults                                                        ( +-  0.01% )

       5.381342641 seconds time elapsed                                          ( +-  0.07% )

The proper work of the huge stack expansion was tested with the
following app:

int main(int argc, char **argv)
{
	char buf[1024 * 1025];

	sprintf(buf, "Hello world !\n");
	printf(buf);

	exit(0);
}

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add include of pagemap.h to fix build errors]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 00:08:25 +10:00
Christophe Leroy
8a0b1120cb powerpc/mm: Use instruction symbolic names in store_updates_sp()
Use symbolic names defined in asm/ppc-opcode.h
instead of hardcoded values.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-25 00:08:24 +10:00
Simon Guo
eacbb218fb powerpc: Export tm_enable()/tm_disable/tm_abort() APIs
This patch exports tm_enable()/tm_disable/tm_abort() APIs, which
will be used for PR KVM transactional memory logic.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-24 16:04:02 +10:00
Nicholas Piggin
0078778a86 powerpc/mm/radix: implement LPID based TLB flushes to be used by KVM
Implement a local TLB flush for invalidating an LPID with variants for
process or partition scope. And a global TLB flush for invalidating
a partition scoped page of an LPID.

These will be used by KVM in subsequent patches.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-17 11:13:29 +10:00
Aneesh Kumar K.V
738f964555 powerpc/mm: Use page fragments for allocation page table at PMD level
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15 22:29:12 +10:00
Aneesh Kumar K.V
8a6c697b99 powerpc/mm: Implement helpers for pagetable fragment support at PMD level
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15 22:29:12 +10:00
Aneesh Kumar K.V
0c4d268029 powerpc/book3s64/mm: Simplify the rcu callback for page table free
Instead of encoding shift in the table address, use an enumerated index value.
This allow us to do different things in the callback for pte and pmd.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15 22:29:11 +10:00
Aneesh Kumar K.V
1c7ec8a40a powerpc/mm/book3s64/4k: Switch 4k pagesize config to use pagetable fragment
4K config use one full page at level 4 of the pagetable. Add support for single
fragment allocation in pagetable fragment code and and use that for 4K config.
This makes both 4k and 64k use the same code path. Later we will switch pmd to
use the page table fragment code. This is done only for 64bit platforms which
is using page table fragment support.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15 22:29:11 +10:00
Aneesh Kumar K.V
702346768c powerpc/mm/nohash: Remove pte fragment dependency from nohash
Now that we have removed 64K page size support, the RCU page table free can
be much simpler for nohash. Make a copy of the the rcu callback to pgalloc.h
header similar to nohash 32. We could possibly merge 32 and 64 bit there. But
that is for a later patch

We also move the book3s specific handler to pgtable_book3s64.c. This will be
updated in a later patch to handle split pmd ptlock.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15 22:29:11 +10:00
Aneesh Kumar K.V
8ce74cffff powerpc/mm: Rename pte fragment functions
We rename the alloc and get_from_cache to indicate they operate on pte
fragments. In later patch we will add pmd fragment support.

No functional change in this patch.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15 22:29:10 +10:00
Aneesh Kumar K.V
af60a4cf87 powerpc/mm: Use pmd_lockptr instead of opencoding it
In later patch we switch pmd_lock from mm->page_table_lock to split pmd ptlock.
It avoid compilations issues, use pmd_lockptr helper.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15 22:29:09 +10:00
Aneesh Kumar K.V
59879d542a powerpc/mm/book3s64: Move book3s64 code to pgtable-book3s64
Only code movement and avoid #ifdef.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15 22:29:09 +10:00
Al Viro
3691d61455 powerpc/syscalls: Switch trivial cases to SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:12 +10:00
Hari Bathini
8597538712 powerpc/fadump: Do not use hugepages when fadump is active
FADump capture kernel boots in restricted memory environment preserving
the context of previous kernel to save vmcore. Supporting hugepages in
such environment makes things unnecessarily complicated, as hugepages
need memory set aside for them. This means most of the capture kernel's
memory is used in supporting hugepages. In most cases, this results in
out-of-memory issues while booting FADump capture kernel. But hugepages
are not of much use in capture kernel whose only job is to save vmcore.
So, disabling hugepages support, when fadump is active, is a reliable
solution for the out of memory issues. Introducing a flag variable to
disable HugeTLB support when fadump is active.

Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-03 23:09:25 +10:00
Eric W. Biederman
3eb0f5193b signal: Ensure every siginfo we send has all bits initialized
Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.

Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.

The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.

In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.

Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25 10:40:51 -05:00
Balbir Singh
fb5924fddf powerpc/mm: Flush cache on memory hot(un)plug
This patch adds support for flushing potentially dirty cache lines
when memory is hot-plugged/hot-un-plugged. The support is currently
limited to 64 bit systems.

The bug was exposed when mappings for a device were actually
hot-unplugged and plugged in back later. A similar issue was observed
during the development of memtrace, but memtrace does it's own
flushing of region via a custom routine.

These patches do a flush both on hotplug/unplug to clear any stale
data in the cache w.r.t mappings, there is a small race window where a
clean cache line may be created again just prior to tearing down the
mapping.

The patches were tested by disabling the flush routines in memtrace
and doing I/O on the trace file. The system immediately
checkstops (quite reliablly if prior to the hot-unplug of the memtrace
region, we memset the regions we are about to hot unplug). After these
patches no custom flushing is needed in the memtrace code.

Fixes: 9d5171a8f2 ("powerpc/powernv: Enable removal of memory for in memory tracing")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Acked-by: Reza Arbab <arbab@linux.ibm.com>
Reviewed-by: Rashmica Gupta <rashmica.g@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-24 09:46:56 +10:00
Linus Torvalds
b1cb4f93b5 powerpc fixes for 4.17 #2
- Fix crashes when loading modules built with a different CONFIG_RELOCATABLE
    value by adding CONFIG_RELOCATABLE to vermagic.
 
  - Fix busy loops in the OPAL NVRAM driver if we get certain error conditions
    from firmware.
 
  - Remove tlbie trace points from KVM code that's called in real mode, because
    it causes crashes.
 
  - Fix checkstops caused by invalid tlbiel on Power9 Radix.
 
  - Ensure the set of CPU features we "know" are always enabled is actually the
    minimal set when we build with support for firmware supplied CPU features.
 
 Thanks to:
   Aneesh Kumar K.V, Anshuman Khandual, Nicholas Piggin.
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Merge tag 'powerpc-4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

 - Fix crashes when loading modules built with a different
   CONFIG_RELOCATABLE value by adding CONFIG_RELOCATABLE to vermagic.

 - Fix busy loops in the OPAL NVRAM driver if we get certain error
   conditions from firmware.

 - Remove tlbie trace points from KVM code that's called in real mode,
   because it causes crashes.

 - Fix checkstops caused by invalid tlbiel on Power9 Radix.

 - Ensure the set of CPU features we "know" are always enabled is
   actually the minimal set when we build with support for firmware
   supplied CPU features.

Thanks to: Aneesh Kumar K.V, Anshuman Khandual, Nicholas Piggin.

* tag 'powerpc-4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Fix CPU_FTRS_ALWAYS vs DT CPU features
  powerpc/mm/radix: Fix checkstops caused by invalid tlbiel
  KVM: PPC: Book3S HV: trace_tlbie must not be called in realmode
  powerpc/8xx: Fix build with hugetlbfs enabled
  powerpc/powernv: Fix OPAL NVRAM driver OPAL_BUSY loops
  powerpc/powernv: define a standard delay for OPAL_BUSY type retry loops
  powerpc/fscr: Enable interrupts earlier before calling get_user()
  powerpc/64s: Fix section mismatch warnings from setup_rfi_flush()
  powerpc/modules: Fix crashes by adding CONFIG_RELOCATABLE to vermagic
2018-04-15 11:57:12 -07:00
Michael Ellerman
2675c13b29 powerpc/mm/radix: Fix checkstops caused by invalid tlbiel
In tlbiel_radix_set_isa300() we use the PPC_TLBIEL() macro to
construct tlbiel instructions. The instruction takes 5 fields, two of
which are registers, and the others are constants. But because it's
constructed with inline asm the compiler doesn't know that.

We got the constraint wrong on the 'r' field, using "r" tells the
compiler to put the value in a register. The value we then get in the
macro is the *register number*, not the value of the field.

That means when we mask the register number with 0x1 we get 0 or 1
depending on which register the compiler happens to put the constant
in, eg:

  li      r10,1
  tlbiel  r8,r9,2,0,0

  li      r7,1
  tlbiel  r10,r6,0,0,1

If we're unlucky we might generate an invalid instruction form, for
example RIC=0, PRS=1 and R=0, tlbiel r8,r7,0,1,0, this has been
observed to cause machine checks:

  Oops: Machine check, sig: 7 [#1]
  CPU: 24 PID: 0 Comm: swapper
  NIP:  00000000000385f4 LR: 000000000100ed00 CTR: 000000000000007f
  REGS: c00000000110bb40 TRAP: 0200
  MSR:  9000000000201003 <SF,HV,ME,RI,LE>  CR: 48002222  XER: 20040000
  CFAR: 00000000000385d0 DAR: 0000000000001c00 DSISR: 00000200 SOFTE: 1

If the machine check happens early in boot while we have MSR_ME=0 it
will escalate into a checkstop and kill the box entirely.

To fix it we could change the inline asm constraint to "i" which
tells the compiler the value is a constant. But a better fix is to just
pass a literal 1 into the macro, which bypasses any problems with inline
asm constraints.

Fixes: d4748276ae ("powerpc/64s: Improve local TLB flush for boot and MCE on POWER9")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
2018-04-12 23:49:55 +10:00
Kees Cook
8f2af155b5 exec: pass stack rlimit into mm layout functions
Patch series "exec: Pin stack limit during exec".

Attempts to solve problems with the stack limit changing during exec
continue to be frustrated[1][2].  In addition to the specific issues
around the Stack Clash family of flaws, Andy Lutomirski pointed out[3]
other places during exec where the stack limit is used and is assumed to
be unchanging.  Given the many places it gets used and the fact that it
can be manipulated/raced via setrlimit() and prlimit(), I think the only
way to handle this is to move away from the "current" view of the stack
limit and instead attach it to the bprm, and plumb this down into the
functions that need to know the stack limits.  This series implements
the approach.

[1] 04e35f4495 ("exec: avoid RLIMIT_STACK races with prlimit()")
[2] 779f4e1c6c ("Revert "exec: avoid RLIMIT_STACK races with prlimit()"")
[3] to security@kernel.org, "Subject: existing rlimit races?"

This patch (of 3):

Since it is possible that the stack rlimit can change externally during
exec (either via another thread calling setrlimit() or another process
calling prlimit()), provide a way to pass the rlimit down into the
per-architecture mm layout functions so that the rlimit can stay in the
bprm structure instead of sitting in the signal structure until exec is
finalized.

Link: http://lkml.kernel.org/r/1518638796-20819-2-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Hugh Dickins <hughd@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Greg KH <greg@kroah.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:37 -07:00
Michal Hocko
666feb21a0 mm, migrate: remove reason argument from new_page_t
No allocation callback is using this argument anymore.  new_page_node
used to use this parameter to convey node_id resp.  migration error up
to move_pages code (do_move_page_to_node_array).  The error status never
made it into the final status field and we have a better way to
communicate node id to the status field now.  All other allocation
callbacks simply ignored the argument so we can drop it finally.

[mhocko@suse.com: fix migration callback]
  Link: http://lkml.kernel.org/r/20180105085259.GH2801@dhcp22.suse.cz
[akpm@linux-foundation.org: fix alloc_misplaced_dst_page()]
[mhocko@kernel.org: fix build]
  Link: http://lkml.kernel.org/r/20180103091134.GB11319@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/20180103082555.14592-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: Andrea Reale <ar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:32 -07:00
Aneesh Kumar K.V
032900e62c powerpc/8xx: Fix build with hugetlbfs enabled
8xx uses the slice code when hugetlbfs is enabled. We missed a header
include on 8xx which resulted in the below build failure:

  config: mpc885_ads_defconfig + CONFIG_HUGETLBFS

  arch/powerpc/mm/slice.c: In function 'slice_get_unmapped_area':
  arch/powerpc/mm/slice.c:655:2: error: implicit declaration of function 'need_extra_context'
  arch/powerpc/mm/slice.c:656:3: error: implicit declaration of function 'alloc_extended_context'

on PPC64 the mmu_context.h was included via linux/pkeys.h

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-11 12:00:23 +10:00
Linus Torvalds
49a695ba72 powerpc updates for 4.17
Notable changes:
 
  - Support for 4PB user address space on 64-bit, opt-in via mmap().
 
  - Removal of POWER4 support, which was accidentally broken in 2016 and no one
    noticed, and blocked use of some modern instructions.
 
  - Workarounds so that the hypervisor can enable Transactional Memory on Power9.
 
  - A series to disable the DAWR (Data Address Watchpoint Register) on Power9.
 
  - More information displayed in the meltdown/spectre_v1/v2 sysfs files.
 
  - A vpermxor (Power8 Altivec) implementation for the raid6 Q Syndrome.
 
  - A big series to make the allocation of our pacas (per cpu area), kernel page
    tables, and per-cpu stacks NUMA aware when using the Radix MMU on Power9.
 
 And as usual many fixes, reworks and cleanups.
 
 Thanks to:
   Aaro Koskinen, Alexandre Belloni, Alexey Kardashevskiy, Alistair Popple, Andy
   Shevchenko, Aneesh Kumar K.V, Anshuman Khandual, Balbir Singh, Benjamin
   Herrenschmidt, Christophe Leroy, Christophe Lombard, Cyril Bur, Daniel Axtens,
   Dave Young, Finn Thain, Frederic Barrat, Gustavo Romero, Horia Geantă,
   Jonathan Neuschäfer, Kees Cook, Larry Finger, Laurent Dufour, Laurent Vivier,
   Logan Gunthorpe, Madhavan Srinivasan, Mark Greer, Mark Hairgrove, Markus
   Elfring, Mathieu Malaterre, Matt Brown, Matt Evans, Mauricio Faria de
   Oliveira, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Paul Mackerras,
   Philippe Bergheaud, Ram Pai, Rob Herring, Sam Bobroff, Segher Boessenkool,
   Simon Guo, Simon Horman, Stewart Smith, Sukadev Bhattiprolu, Suraj Jitindar
   Singh, Thiago Jung Bauermann, Vaibhav Jain, Vaidyanathan Srinivasan, Vasant
   Hegde, Wei Yongjun.
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Merge tag 'powerpc-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Support for 4PB user address space on 64-bit, opt-in via mmap().

   - Removal of POWER4 support, which was accidentally broken in 2016
     and no one noticed, and blocked use of some modern instructions.

   - Workarounds so that the hypervisor can enable Transactional Memory
     on Power9.

   - A series to disable the DAWR (Data Address Watchpoint Register) on
     Power9.

   - More information displayed in the meltdown/spectre_v1/v2 sysfs
     files.

   - A vpermxor (Power8 Altivec) implementation for the raid6 Q
     Syndrome.

   - A big series to make the allocation of our pacas (per cpu area),
     kernel page tables, and per-cpu stacks NUMA aware when using the
     Radix MMU on Power9.

  And as usual many fixes, reworks and cleanups.

  Thanks to: Aaro Koskinen, Alexandre Belloni, Alexey Kardashevskiy,
  Alistair Popple, Andy Shevchenko, Aneesh Kumar K.V, Anshuman Khandual,
  Balbir Singh, Benjamin Herrenschmidt, Christophe Leroy, Christophe
  Lombard, Cyril Bur, Daniel Axtens, Dave Young, Finn Thain, Frederic
  Barrat, Gustavo Romero, Horia Geantă, Jonathan Neuschäfer, Kees Cook,
  Larry Finger, Laurent Dufour, Laurent Vivier, Logan Gunthorpe,
  Madhavan Srinivasan, Mark Greer, Mark Hairgrove, Markus Elfring,
  Mathieu Malaterre, Matt Brown, Matt Evans, Mauricio Faria de Oliveira,
  Michael Neuling, Naveen N. Rao, Nicholas Piggin, Paul Mackerras,
  Philippe Bergheaud, Ram Pai, Rob Herring, Sam Bobroff, Segher
  Boessenkool, Simon Guo, Simon Horman, Stewart Smith, Sukadev
  Bhattiprolu, Suraj Jitindar Singh, Thiago Jung Bauermann, Vaibhav
  Jain, Vaidyanathan Srinivasan, Vasant Hegde, Wei Yongjun"

* tag 'powerpc-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (207 commits)
  powerpc/64s/idle: Fix restore of AMOR on POWER9 after deep sleep
  powerpc/64s: Fix POWER9 DD2.2 and above in cputable features
  powerpc/64s: Fix pkey support in dt_cpu_ftrs, add CPU_FTR_PKEY bit
  powerpc/64s: Fix dt_cpu_ftrs to have restore_cpu clear unwanted LPCR bits
  Revert "powerpc/64s/idle: POWER9 ESL=0 stop avoid save/restore overhead"
  powerpc: iomap.c: introduce io{read|write}64_{lo_hi|hi_lo}
  powerpc: io.h: move iomap.h include so that it can use readq/writeq defs
  cxl: Fix possible deadlock when processing page faults from cxllib
  powerpc/hw_breakpoint: Only disable hw breakpoint if cpu supports it
  powerpc/mm/radix: Update command line parsing for disable_radix
  powerpc/mm/radix: Parse disable_radix commandline correctly.
  powerpc/mm/hugetlb: initialize the pagetable cache correctly for hugetlb
  powerpc/mm/radix: Update pte fragment count from 16 to 256 on radix
  powerpc/mm/keys: Update documentation and remove unnecessary check
  powerpc/64s/idle: POWER9 ESL=0 stop avoid save/restore overhead
  powerpc/64s/idle: Consolidate power9_offline_stop()/power9_idle_stop()
  powerpc/powernv: Always stop secondaries before reboot/shutdown
  powerpc: hard disable irqs in smp_send_stop loop
  powerpc: use NMI IPI for smp_send_stop
  powerpc/powernv: Fix SMT4 forcing idle code
  ...
2018-04-07 12:08:19 -07:00
Dan Williams
09135cc594 mm, powerpc: use vma_kernel_pagesize() in vma_mmu_pagesize()
Patch series "mm, smaps: MMUPageSize for device-dax", v3.

Similar to commit 31383c6865 ("mm, hugetlbfs: introduce ->split() to
vm_operations_struct") here is another occasion where we want
special-case hugetlbfs/hstate enabling to also apply to device-dax.

This prompts the question what other hstate conversions we might do
beyond ->split() and ->pagesize(), but this appears to be the last of
the usages of hstate_vma() in generic/non-hugetlbfs specific code paths.

This patch (of 3):

The current powerpc definition of vma_mmu_pagesize() open codes looking
up the page size via hstate.  It is identical to the generic
vma_kernel_pagesize() implementation.

Now, vma_kernel_pagesize() is growing support for determining the page
size of Device-DAX vmas in addition to the existing Hugetlbfs page size
determination.

Ideally, if the powerpc vma_mmu_pagesize() used vma_kernel_pagesize() it
would automatically benefit from any new vma-type support that is added
to vma_kernel_pagesize().  However, the powerpc vma_mmu_pagesize() is
prevented from calling vma_kernel_pagesize() due to a circular header
dependency that requires vma_mmu_pagesize() to be defined before
including <linux/hugetlb.h>.

Break this circular dependency by defining the default vma_mmu_pagesize()
as a __weak symbol to be overridden by the powerpc version.

Link: http://lkml.kernel.org/r/151996254179.27922.2213728278535578744.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Jane Chu <jane.chu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:26 -07:00
Anshuman Khandual
310253514b mm/migrate: rename migration reason MR_CMA to MR_CONTIG_RANGE
alloc_contig_range() initiates compaction and eventual migration for the
purpose of either CMA or HugeTLB allocations.  At present, the reason
code remains the same MR_CMA for either of these cases.  Let's make it
MR_CONTIG_RANGE which will appropriately reflect the reason code in both
these cases.

Link: http://lkml.kernel.org/r/20180202091518.18798-1-khandual@linux.vnet.ibm.com
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:24 -07:00
Aneesh Kumar K.V
cec4e9b28f powerpc/mm/radix: Parse disable_radix commandline correctly.
kernel parameter disable_radix takes different options
disable_radix=yes|no|1|0 or just disable_radix. When using the later
format we get below error.

 `Malformed early option 'disable_radix'`

Fixes: 1fd6c02207 ("powerpc/mm: Add a CONFIG option to choose if radix is used by default")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 16:59:36 +10:00
Aneesh Kumar K.V
6fa504835d powerpc/mm/hugetlb: initialize the pagetable cache correctly for hugetlb
With 64k page size, we have hugetlb pte entries at the pmd and pud level for
book3s64. We don't need to create a separate page table cache for that. With 4k
we need to make sure hugepd page table cache for 16M is placed at PUD level
and 16G at the PGD level.

Simplify all these by not using HUGEPD_PD_SHIFT which is confusing for book3s64.

Without this patch, with 64k page size we create pagetable caches with shift
value 10 and 7 which are not used at all.

Fixes: 419df06eea ("powerpc: Reduce the PTE_INDEX_SIZE")

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 16:58:53 +10:00
Aneesh Kumar K.V
fb4e5dbd44 powerpc/mm/radix: Update pte fragment count from 16 to 256 on radix
With split PTL (page table lock) config, we allocate the level
4 (leaf) page table using pte fragment framework instead of slab cache
like other levels. This was done to enable us to have split page table
lock at the level 4 of the page table. We use page->plt backing the
all the level 4 pte fragment for the lock.

Currently with Radix, we use only 16 fragments out of the allocated
page. In radix each fragment is 256 bytes which means we use only 4k
out of the allocated 64K page wasting 60k of the allocated memory.
This was done earlier to keep it closer to hash.

This patch update the pte fragment count to 256, thereby using the
full 64K page and reducing the memory usage. Performance tests shows
really low impact even with THP disabled. With THP disabled we will be
contenting further less on level 4 ptl and hence the impact should be
further low.

  256 threads:
    without patch (10 runs of ./ebizzy  -m -n 1000 -s 131072 -S 100)
      median = 15678.5
      stdev = 42.1209

    with patch:
      median = 15354
      stdev = 194.743

This is with THP disabled. With THP enabled the impact of the patch
will be less.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 16:58:06 +10:00
Aneesh Kumar K.V
f2ed480fa4 powerpc/mm/keys: Update documentation and remove unnecessary check
Adds more code comments. We also remove an unnecessary pkey check
after we check for pkey error in this patch.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 15:23:09 +10:00
Mathieu Malaterre
19e68b2aec powerpc/mm/radix: Fix always false comparison against MMU_NO_CONTEXT
In commit 9690c15742 ("powerpc/mm/radix: Fix always false comparison
against MMU_NO_CONTEXT") an issue was discovered where `mm->context.id` was
being truncated to an `unsigned int`, while the PID is actually an
`unsigned long`. Update the earlier patch by fixing one remaining
occurrence. Discovered during a compilation with W=1:

  arch/powerpc/mm/tlb-radix.c:702:19: error: comparison is always false due to limited range of data type [-Werror=type-limits]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 22:15:34 +10:00
Nicholas Piggin
471d7ff8b5 powerpc/64s: Remove POWER4 support
POWER4 has been broken since at least the change 49d09bf2a6
("powerpc/64s: Optimise MSR handling in exception handling"), which
requires mtmsrd L=1 support. This was introduced in ISA v2.01, and
POWER4 supports ISA v2.00.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:50 +11:00
Jonathan Neuschäfer
7e1405917c powerpc/mm/32: Remove the reserved memory hack
This hack, introduced in commit c5df7f7751 ("powerpc: allow ioremap
within reserved memory regions") is now unnecessary.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:44 +11:00
Jonathan Neuschäfer
2bbf63264a powerpc/mm/32: Use page_is_ram to check for RAM
On systems where there is MMIO space between different blocks of RAM in
the physical address space, __ioremap_caller did not allow mapping these
MMIO areas, because they were below the end RAM and thus considered RAM
as well.  Use the memblock-based page_is_ram function, which returns
false for such MMIO holes.

v2:
  Keep the check for p < virt_to_phys(high_memory). On 32-bit systems
  with high memory (memory above physical address 4GiB), the high memory
  is expected to be available though ioremap. The high_memory variable
  marks the end of low memory; comparing against it means that only
  ioremap requests for low RAM will be denied.
  Reported by Michael Ellerman.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:43 +11:00
Jonathan Neuschäfer
f65e67c7e3 powerpc/mm: Use memblock API for PPC32 page_is_ram
To support accurate checking for different blocks of memory on PPC32,
use the same memblock-based approach that's already used on PPC64 also
on PPC32.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:42 +11:00
Jonathan Neuschäfer
2615c93e5f powerpc/mm: Simplify page_is_ram by using memblock_is_memory
Instead of open-coding the search in page_is_ram, call memblock_is_memory.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:42 +11:00
Michael Ellerman
f437c51748 Merge branch 'topic/paca' into next
Bring in yet another series that touches KVM code, and might need to
be merged into the kvm-ppc branch to resolve conflicts.

This required some changes in pnv_power9_force_smt4_catch/release()
due to the paca array becomming an array of pointers.
2018-03-31 09:09:36 +11:00
Aneesh Kumar K.V
c2b4d8b741 powerpc/mm/hash64: Increase the VA range
This patch increases the max virtual (effective) address value to 4PB.
With 4K page size config we continue to limit ourself to 64TB.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Keep the H_PGTABLE_RANGE test, update it to work]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:38 +11:00
Aneesh Kumar K.V
f384796c40 powerpc/mm: Add support for handling > 512TB address in SLB miss
For addresses above 512TB we allocate additional mmu contexts. To make
it all easy, addresses above 512TB are handled with IR/DR=1 and with
stack frame setup.

The mmu_context_t is also updated to track the new extended_ids. To
support upto 4PB we need a total 8 contexts.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Minor formatting tweaks and comment wording, switch BUG to WARN
      in get_ea_context().]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:38 +11:00
Aneesh Kumar K.V
0dea04b288 powerpc/mm/slice: Consolidate return path in slice_get_unmapped_area()
In a following patch, on finding a free area we will need to do
allocatinon of extra contexts as needed. Consolidating the return path
for slice_get_unmapped_area() will make that easier.

Split into a separate patch to make review easy.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:37 +11:00
Ram Pai
f208638680 powerpc/mm: Fix thread_pkey_regs_init()
thread_pkey_regs_init() initializes the pkey related registers
instead of initializing the fields in the task structures.  Fortunately
those key related registers are re-set to zero when the task
gets scheduled on the cpu. However its good to fix this glaringly
visible error.

Fixes: 06bb53b338 ("powerpc: store and restore the pkey state across context switches")
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:33 +11:00
Nicholas Piggin
29ab6c4708 powerpc/mm: Pass node id into create_section_mapping
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Move __map_kernel_page_nid() inside #ifdef SPARSEMEM_VMEMMAP]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:07:10 +11:00
Nicholas Piggin
2ad452ffaa powerpc/64s/radix: Allocate kernel page tables node-local if possible
Try to allocate kernel page tables for direct mapping and vmemmap
according to the node of the memory they will map. The node is not
available for the linear map in early boot, so use range allocation
to allocate the page tables from the region they map, which is
effectively node-local.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fix build error in radix__create_section_mapping()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:07:09 +11:00
Nicholas Piggin
0633dafcf8 powerpc/64s/radix: Split early page table mapping to its own function
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:07:09 +11:00
Nicholas Piggin
9bd9be006c powerpc/mm/numa: move numa topology discovery earlier
Split sparsemem initialisation from basic numa topology discovery.
Move the parsing earlier in boot, before pacas are allocated.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:26 +11:00
Nicholas Piggin
499dcd4137 powerpc/64s: Allocate LPPACAs individually
We no longer allocate lppacas in an array, so this patch removes the
1kB static alignment for the structure, and enforces the PAPR
alignment requirements at allocation time. We can not reduce the 1kB
allocation size however, due to existing KVM hypervisors.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:24 +11:00
Nicholas Piggin
d2e60075a3 powerpc/64: Use array of paca pointers and allocate pacas individually
Change the paca array into an array of pointers to pacas. Allocate
pacas individually.

This allows flexibility in where the PACAs are allocated. Future work
will allocate them node-local. Platforms that don't have address limits
on PACAs would be able to defer PACA allocations until later in boot
rather than allocate all possible ones up-front then freeing unused.

This is slightly more overhead (one additional indirection) for cross
CPU paca references, but those aren't too common.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:23 +11:00
Michael Ellerman
95dff480bb Merge branch 'fixes' into next
Merge our fixes branch from the 4.16 cycle.

There were a number of important fixes merged, in particular some Power9
workarounds that we want in next for testing purposes. There's also been
some conflicting changes in the CPU features code which are best merged
and tested before going upstream.
2018-03-28 22:59:50 +11:00
Alexey Kardashevskiy
b574df9488 powerpc/mm: Fix typo in comments
Fixes: 912cc87a6 "powerpc/mm/radix: Add LPID based tlb flush helpers"
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27 23:44:56 +11:00
Mauricio Faria de Oliveira
bde709a708 powerpc/mm: Fix section mismatch warning in stop_machine_change_mapping()
Fix the warning messages for stop_machine_change_mapping(), and a number
of other affected functions in its call chain.

All modified functions are under CONFIG_MEMORY_HOTPLUG, so __meminit
is okay (keeps them / does not discard them).

Boot-tested on powernv/power9/radix-mmu and pseries/power8/hash-mmu.

    $ make -j$(nproc) CONFIG_DEBUG_SECTION_MISMATCH=y vmlinux
    ...
      MODPOST vmlinux.o
    WARNING: vmlinux.o(.text+0x6b130): Section mismatch in reference from the function stop_machine_change_mapping() to the function .meminit.text:create_physical_mapping()
    The function stop_machine_change_mapping() references
    the function __meminit create_physical_mapping().
    This is often because stop_machine_change_mapping lacks a __meminit
    annotation or the annotation of create_physical_mapping is wrong.

    WARNING: vmlinux.o(.text+0x6b13c): Section mismatch in reference from the function stop_machine_change_mapping() to the function .meminit.text:create_physical_mapping()
    The function stop_machine_change_mapping() references
    the function __meminit create_physical_mapping().
    This is often because stop_machine_change_mapping lacks a __meminit
    annotation or the annotation of create_physical_mapping is wrong.
    ...

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27 23:44:55 +11:00
Paul Mackerras
dbfcf3cb9c powerpc/64: Call H_REGISTER_PROC_TBL when running as a HPT guest on POWER9
On POWER9, since commit cc3d294013 ("powerpc/64: Enable use of radix
MMU under hypervisor on POWER9", 2017-01-30), we set both the radix and
HPT bits in the client-architecture-support (CAS) vector, which tells
the hypervisor that we can do either radix or HPT.  According to PAPR,
if we use this combination we are promising to do a H_REGISTER_PROC_TBL
hcall later on to let the hypervisor know whether we are doing radix
or HPT.  We currently do this call if we are doing radix but not if
we are doing HPT.  If the hypervisor is able to support both radix
and HPT guests, it would be entitled to defer allocation of the HPT
until the H_REGISTER_PROC_TBL call, and to fail any attempts to create
HPTEs until the H_REGISTER_PROC_TBL call.  Thus we need to do a
H_REGISTER_PROC_TBL call when we are doing HPT; otherwise we may
crash at boot time.

This adds the code to call H_REGISTER_PROC_TBL in this case, before
we attempt to create any HPT entries using H_ENTER.

Fixes: cc3d294013 ("powerpc/64: Enable use of radix MMU under hypervisor on POWER9")
Cc: stable@vger.kernel.org # v4.11+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27 19:25:08 +11:00
Aneesh Kumar K.V
a5d4b5891c powerpc/mm: Fixup tlbie vs store ordering issue on POWER9
On POWER9, under some circumstances, a broadcast TLB invalidation
might complete before all previous stores have drained, potentially
allowing stale stores from becoming visible after the invalidation.
This works around it by doubling up those TLB invalidations which was
verified by HW to be sufficient to close the risk window.

This will be documented in a yet-to-be-published errata.

Fixes: 1a472c9dba ("powerpc/mm/radix: Add tlbflush routines")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Enable the feature in the DT CPU features code for all Power9,
      rename the feature to CPU_FTR_P9_TLBIE_BUG per benh.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-23 20:48:03 +11:00
Aneesh Kumar K.V
243fee3249 powerpc/mm/radix: Move the functions that does the actual tlbie closer
No functionality change. Just code movement to ease code changes later

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-23 16:17:42 +11:00
Aneesh Kumar K.V
99491e2d0e powerpc/mm/radix: Remove unused code
These function are not used in the code. Remove them.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-23 16:17:39 +11:00
Benjamin Herrenschmidt
80a4ae202f powerpc/mm: Workaround Nest MMU bug with TLB invalidations
On POWER9 the Nest MMU may fail to invalidate some translations when
doing a tlbie "by PID" or "by LPID" that is targeted at the TLB only
and not the page walk cache.

This works around it by forcing such invalidations to escalate to
RIC=2 (full invalidation of TLB *and* PWC) when a coprocessor is in
use for the context.

Fixes: 03b8abedf4 ("cxl: Enable global TLBIs for cxl contexts")
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[balbirs: fixed spelling and coding style to quiesce checkpatch.pl]
Tested-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-23 14:16:58 +11:00
Benjamin Herrenschmidt
aff6f8cb3e powerpc/mm: Add tracking of the number of coprocessors using a context
Currently, when using coprocessors (which use the Nest MMU), we
simply increment the active_cpu count to force all TLB invalidations
to be come broadcast.

Unfortunately, due to an errata in POWER9, we will need to know
more specifically that coprocessors are in use.

This maintains a separate copros counter in the MMU context for
that purpose.

NB. The commit mentioned in the fixes tag below is not at fault for
the bug we're fixing in this commit and the next, but this fix applies
on top the infrastructure it introduced.

Fixes: 03b8abedf4 ("cxl: Enable global TLBIs for cxl contexts")
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-23 14:14:31 +11:00
Nicholas Piggin
014a32b30e powerpc/mm/slice: remove radix calls to the slice code
This is a tidy up which removes radix MMU calls into the slice
code.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 23:43:08 +11:00
Nicholas Piggin
d262bd5a73 powerpc/mm/slice: Use const pointers to cached slice masks where possible
The slice_mask cache was a basic conversion which copied the slice
mask into caller's structures, because that's how the original code
worked. In most cases the pointer can be used directly instead, saving
a copy and an on-stack structure.

On POWER8, this increases vfork+exec+exit performance by 0.3%
and reduces time to mmap+munmap a 64kB page by 2%.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 23:43:08 +11:00
Nicholas Piggin
7490755830 powerpc/mm/slice: remove dead code
This code is never compiled in, and it gets broken by the next
patch, so remove it.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 23:43:07 +11:00
Nicholas Piggin
b8c9354914 powerpc/mm/slice: Switch to 3-operand slice bitops helpers
This converts the slice_mask bit operation helpers to be the usual
3-operand kind, which allows 2 inputs to set a different output
without an extra copy, which is used in the next patch.

Adds slice_copy_mask, which will be used in the next patch.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 23:43:07 +11:00
Nicholas Piggin
ae3066bd1c powerpc/mm/slice: implement slice_check_range_fits
Rather than build slice masks from a range then use that to check for
fit in a candidate mask, implement slice_check_range_fits that checks
if a range fits in a mask directly.

This allows several structures to be removed from stacks, and also we
don't expect a huge range in a lot of these cases, so building and
comparing a full mask is going to be more expensive than testing just
one or two bits of the range.

On POWER8, this increases vfork+exec+exit performance by 0.3%
and reduces time to mmap+munmap a 64kB page by 5%.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 23:43:06 +11:00
Nicholas Piggin
5709f7cfd8 powerpc/mm/slice: implement a slice mask cache
Calculating the slice mask can become a signifcant overhead for
get_unmapped_area. This patch adds a struct slice_mask for
each page size in the mm_context, and keeps these in synch with
the slices psize arrays and slb_addr_limit.

On Book3S/64 this adds 288 bytes to the mm_context_t for the
slice mask caches.

On POWER8, this increases vfork+exec+exit performance by 9.9%
and reduces time to mmap+munmap a 64kB page by 28%.

Reduces time to mmap+munmap by about 10% on 8xx.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 23:43:06 +11:00
Nicholas Piggin
830fd2d45a powerpc/mm/slice: pass pointers to struct slice_mask where possible
Pass around const pointers to struct slice_mask where possible, rather
than copies of slice_mask, to reduce stack and call overhead.

checkstack.pl gives, before:
0x00000d1c slice_get_unmapped_area [slice.o]:		592
0x00001864 is_hugepage_only_range [slice.o]:		448
0x00000754 slice_find_area_topdown [slice.o]:		400
0x00000484 slice_find_area_bottomup.isra.1 [slice.o]:	272
0x000017b4 slice_set_range_psize [slice.o]:		224
0x00000a4c slice_find_area [slice.o]:			128
0x00000160 slice_check_fit [slice.o]:			112

after:
0x00000ad0 slice_get_unmapped_area [slice.o]:		448
0x00001464 is_hugepage_only_range [slice.o]:		288
0x000006c0 slice_find_area [slice.o]:			144
0x0000016c slice_check_fit [slice.o]:			128
0x00000528 slice_find_area_bottomup.isra.2 [slice.o]:	128
0x000013e4 slice_set_range_psize [slice.o]:		128

This increases vfork+exec+exit performance by 1.5%.

Reduces time to mmap+munmap a 64kB page by 17%.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 23:43:05 +11:00
Nicholas Piggin
5a807e04bd powerpc/mm/slice: tidy lpsizes and hpsizes update loops
Make these loops look the same, and change their form so the
important part is not wrapped over so many lines.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 23:43:05 +11:00
Nicholas Piggin
1753dd1830 powerpc/mm/slice: Simplify and optimise slice context initialisation
The slice state of an mm gets zeroed then initialised upon exec.
This is the only caller of slice_set_user_psize now, so that can be
removed and instead implement a faster and simplified approach that
requires no locking or checking existing state.

This speeds up vfork+exec+exit performance on POWER8 by 3%.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 23:43:05 +11:00
Mathieu Malaterre
d15a261d87 powerpc/32: Make some functions static
These functions can all be static, make it so.

Signed-off-by: Mathieu Malaterre <malat@debian.org>
[mpe: Combine a patch of Mathieu's with some other static conversions]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 15:50:42 +11:00
Anshuman Khandual
3d4f5f5848 powerpc/mm: Drop the function native_register_proc_table()
This is left over from the segment table implementation and not getting
called from any where now. Hence just drop it.

Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 15:50:27 +11:00
Christophe Leroy
15472423ce powerpc/mm/slice: Allow up to 64 low slices
While the implementation of the "slices" address space allows
a significant amount of high slices, it limits the number of
low slices to 16 due to the use of a single u64 low_slices_psize
element in struct mm_context_t

On the 8xx, the minimum slice size is the size of the area
covered by a single PMD entry, ie 4M in 4K pages mode and 64M in
16K pages mode. This means we could have at least 64 slices.

In order to override this limitation, this patch switches the
handling of low_slices_psize to char array as done already for
high_slices_psize.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-06 09:21:23 +11:00
Christophe Leroy
aa0ab02ba9 powerpc/mm/slice: Fix hugepage allocation at hint address on 8xx
On the 8xx, the page size is set in the PMD entry and applies to
all pages of the page table pointed by the said PMD entry.

When an app has some regular pages allocated (e.g. see below) and tries
to mmap() a huge page at a hint address covered by the same PMD entry,
the kernel accepts the hint allthough the 8xx cannot handle different
page sizes in the same PMD entry.

10000000-10001000 r-xp 00000000 00:0f 2597 /root/malloc
10010000-10011000 rwxp 00000000 00:0f 2597 /root/malloc

mmap(0x10080000, 524288, PROT_READ|PROT_WRITE,
     MAP_PRIVATE|MAP_ANONYMOUS|0x40000, -1, 0) = 0x10080000

This results the app remaining forever in do_page_fault()/hugetlb_fault()
and when interrupting that app, we get the following warning:

[162980.035629] WARNING: CPU: 0 PID: 2777 at arch/powerpc/mm/hugetlbpage.c:354 hugetlb_free_pgd_range+0xc8/0x1e4
[162980.035699] CPU: 0 PID: 2777 Comm: malloc Tainted: G W       4.14.6 #85
[162980.035744] task: c67e2c00 task.stack: c668e000
[162980.035783] NIP:  c000fe18 LR: c00e1eec CTR: c00f90c0
[162980.035830] REGS: c668fc20 TRAP: 0700   Tainted: G W        (4.14.6)
[162980.035854] MSR:  00029032 <EE,ME,IR,DR,RI>  CR: 24044224 XER: 20000000
[162980.036003]
[162980.036003] GPR00: c00e1eec c668fcd0 c67e2c00 00000010 c6869410 10080000 00000000 77fb4000
[162980.036003] GPR08: ffff0001 0683c001 00000000 ffffff80 44028228 10018a34 00004008 418004fc
[162980.036003] GPR16: c668e000 00040100 c668e000 c06c0000 c668fe78 c668e000 c6835ba0 c668fd48
[162980.036003] GPR24: 00000000 73ffffff 74000000 00000001 77fb4000 100fffff 10100000 10100000
[162980.036743] NIP [c000fe18] hugetlb_free_pgd_range+0xc8/0x1e4
[162980.036839] LR [c00e1eec] free_pgtables+0x12c/0x150
[162980.036861] Call Trace:
[162980.036939] [c668fcd0] [c00f0774] unlink_anon_vmas+0x1c4/0x214 (unreliable)
[162980.037040] [c668fd10] [c00e1eec] free_pgtables+0x12c/0x150
[162980.037118] [c668fd40] [c00eabac] exit_mmap+0xe8/0x1b4
[162980.037210] [c668fda0] [c0019710] mmput.part.9+0x20/0xd8
[162980.037301] [c668fdb0] [c001ecb0] do_exit+0x1f0/0x93c
[162980.037386] [c668fe00] [c001f478] do_group_exit+0x40/0xcc
[162980.037479] [c668fe10] [c002a76c] get_signal+0x47c/0x614
[162980.037570] [c668fe70] [c0007840] do_signal+0x54/0x244
[162980.037654] [c668ff30] [c0007ae8] do_notify_resume+0x34/0x88
[162980.037744] [c668ff40] [c000dae8] do_user_signal+0x74/0xc4
[162980.037781] Instruction dump:
[162980.037821] 7fdff378 81370000 54a3463a 80890020 7d24182e 7c841a14 712a0004 4082ff94
[162980.038014] 2f890000 419e0010 712a0ff0 408200e0 <0fe00000> 54a9000a 7f984840 419d0094
[162980.038216] ---[ end trace c0ceeca8e7a5800a ]---
[162980.038754] BUG: non-zero nr_ptes on freeing mm: 1
[162985.363322] BUG: non-zero nr_ptes on freeing mm: -1

In order to fix this, this patch uses the address space "slices"
implemented for BOOK3S/64 and enhanced to support PPC32 by the
preceding patch.

This patch modifies the context.id on the 8xx to be in the range
[1:16] instead of [0:15] in order to identify context.id == 0 as
not initialised contexts as done on BOOK3S

This patch activates CONFIG_PPC_MM_SLICES when CONFIG_HUGETLB_PAGE is
selected for the 8xx

Alltough we could in theory have as many slices as PMD entries, the
current slices implementation limits the number of low slices to 16.
This limitation is not preventing us to fix the initial issue allthough
it is suboptimal. It will be cured in a subsequent patch.

Fixes: 4b91428699 ("powerpc/8xx: Implement support of hugepages")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-06 09:21:23 +11:00
Christophe Leroy
db3a528db4 powerpc/mm/slice: Enhance for supporting PPC32
In preparation for the following patch which will fix an issue on
the 8xx by re-using the 'slices', this patch enhances the
'slices' implementation to support 32 bits CPUs.

On PPC32, the address space is limited to 4Gbytes, hence only the low
slices will be used.

The high slices use bitmaps. As bitmap functions are not prepared to
handle bitmaps of size 0, this patch ensures that bitmap functions
are called only when SLICE_NUM_HIGH is not nul.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-06 09:21:23 +11:00
Christophe Leroy
326691ad4f powerpc/mm/slice: Remove intermediate bitmap copy
bitmap_or() and bitmap_andnot() can work properly with dst identical
to src1 or src2. There is no need of an intermediate result bitmap
that is copied back to dst in a second step.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-06 09:21:22 +11:00
Bharata B Rao
2f7d03e051 powerpc/mm/drmem: Fix unexpected flag value in ibm,dynamic-memory-v2
Memory addtion and removal by count and indexed-count methods
temporarily mark the LMBs that are being added/removed by a special
flag value DRMEM_LMB_RESERVED. Accessing flags value directly at a few
places without proper accessor method is causing two unexpected
side-effects:

- DRMEM_LMB_RESERVED bit is becoming part of the flags word of
  drconf_cell_v2 entries in ibm,dynamic-memory-v2 DT property.
- This results in extra drconf_cell entries in ibm,dynamic-memory-v2.
  For example if 1G memory is added, it leads to one entry for 3 LMBs
  and 1 separate entry for the last LMB. All the 4 LMBs should be
  defined by one entry here.

Fix this by always accessing the flags by its accessor method
drmem_lmb_flags().

Fixes: 2b31e3aec1 ("powerpc/drmem: Add support for ibm, dynamic-memory-v2 property")
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-23 16:45:51 +11:00
Nathan Fontenot
2c10636a0b powerpc/pseries: Check for zero filled ibm,dynamic-memory property
Some versions of QEMU will produce an ibm,dynamic-reconfiguration-memory
node with a ibm,dynamic-memory property that is zero-filled. This
causes the drmem code to oops trying to parse this property.

The fix for this is to validate that the property does contain LMB
entries before trying to parse it and bail if the count is zero.

  Oops: Kernel access of bad area, sig: 11 [#1]
  DAR: 0000000000000010
  NIP read_drconf_v1_cell+0x54/0x9c
  LR  read_drconf_v1_cell+0x48/0x9c
  Call Trace:
    __param_initcall_debug+0x0/0x28 (unreliable)
    drmem_init+0x144/0x2f8
    do_one_initcall+0x64/0x1d0
    kernel_init_freeable+0x298/0x38c
    kernel_init+0x24/0x160
    ret_from_kernel_thread+0x5c/0xb4

The ibm,dynamic-reconfiguration-memory device tree property generated
that causes this:

  ibm,dynamic-reconfiguration-memory {
          ibm,lmb-size = <0x0 0x10000000>;
          ibm,memory-flags-mask = <0xff>;
          ibm,dynamic-memory = <0x0 0x0 0x0 0x0 0x0 0x0>;
          linux,phandle = <0x7e57eed8>;
          ibm,associativity-lookup-arrays = <0x1 0x4 0x0 0x0 0x0 0x0>;
          ibm,memory-preservation-time = <0x0>;
  };

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Tested-by: Daniel Black <daniel@linux.vnet.ibm.com>
[mpe: Trim oops report]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-16 21:34:14 +11:00
Aneesh Kumar K.V
ff31e10546 powerpc/mm/hash64: Store the slot information at the right offset for hugetlb
The hugetlb pte entries are at the PMD and PUD level, so we can't use
PTRS_PER_PTE to find the second half of the page table. Use the right
offset for PUD/PMD to get to the second half of the table.

Fixes: bf9a95f9a6 ("powerpc: Free up four 64K PTE bits in 64K backed HPTE pages")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-13 22:37:48 +11:00
Aneesh Kumar K.V
fae2211697 powerpc/mm: Fix crashes with 16G huge pages
To support memory keys, we moved the hash pte slot information to the
second half of the page table. This was ok with PTE entries at level
4 (PTE page) and level 3 (PMD). We already allocate larger page table
pages at those levels to accomodate extra details. For level 4 we
already have the extra space which was used to track 4k hash page
table entry details and at level 3 the extra space was allocated to
track the THP details.

With hugetlbfs PTE, we used this extra space at the PMD level to store
the slot details. But we also support hugetlbfs PTE at PUD level for
16GB pages and PUD level page didn't allocate extra space. This
resulted in memory corruption.

Fix this by allocating extra space at PUD level when HUGETLB is
enabled.

Fixes: bf9a95f9a6 ("powerpc: Free up four 64K PTE bits in 64K backed HPTE pages")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-13 22:37:47 +11:00
Alexey Kardashevskiy
62e984ddfd powerpc/mm: Flush radix process translations when setting MMU type
Radix guests do normally invalidate process-scoped translations when a
new pid is allocated but migrated guests do not invalidate these so
migrated guests crash sometime, especially easy to reproduce with
migration happening within first 10 seconds after the guest boot start
on the same machine.

This adds the "Invalidate process-scoped translations" flush to fix
radix guests migration.

Fixes: 2ee13be34b ("KVM: PPC: Book3S HV: Update kvmppc_set_arch_compat() for ISA v3.00")
Cc: stable@vger.kernel.org # v4.10+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Tested-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-13 22:37:47 +11:00
Balbir Singh
4dd5f8a99e powerpc/mm/radix: Split linear mapping on hot-unplug
This patch splits the linear mapping if the hot-unplug range is
smaller than the mapping size. The code detects if the mapping needs
to be split into a smaller size and if so, uses the stop machine
infrastructure to clear the existing mapping and then remap the
remaining range using a smaller page size.

The code will skip any region of the mapping that overlaps with kernel
text and warn about it once. We don't want to remove a mapping where
the kernel text and the LMB we intend to remove overlap in the same
TLB mapping as it may affect the currently executing code.

I've tested these changes under a kvm guest with 2 vcpus, from a split
mapping point of view, some of the caveats mentioned above applied to
the testing I did.

Fixes: 4b5d62ca17 ("powerpc/mm: add radix__remove_section_mapping()")
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[mpe: Tweak change log to match updated behaviour]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-08 23:56:11 +11:00
Nicholas Piggin
eeb715c3e9 powerpc/64s/radix: Boot-time NULL pointer protection using a guard-PID
This change restores and formalises the behaviour that access to NULL
or other user addresses by the kernel during boot should fault rather
than succeed and modify memory. This was inadvertently broken when
fixing another bug, because it was previously not well defined and
only worked by chance.

powerpc/64s/radix uses high address bits to select an address space
"quadrant", which determines which PID and LPID are used to translate
the rest of the address (effective PID, effective LPID). The kernel
mapping at 0xC... selects quadrant 3, which uses PID=0 and LPID=0. So
the kernel page tables are installed in the PID 0 process table entry.

An address at 0x0... selects quadrant 0, which uses PID=PIDR for
translating the rest of the address (that is, it uses the value of the
PIDR register as the effective PID). If PIDR=0, then the translation
is performed with the PID 0 process table entry page tables. This is
the kernel mapping, so we effectively get another copy of the kernel
address space at 0. A NULL pointer access will access physical memory
address 0.

To prevent duplicating the kernel address space in quadrant 0, this
patch allocates a guard PID containing no translations, and
initializes PIDR with this during boot, before the MMU is switched on.
Any kernel access to quadrant 0 will use this guard PID for
translation and find no valid mappings, and therefore fault.

After boot, this PID will be switchd away to user context PIDs, but
those contain user mappings (and usually NULL pointer protection)
rather than kernel mapping, which is much safer (and by design). It
may be in future this is tightened further, which the guard PID could
be used for.

Commit 371b8044 ("powerpc/64s: Initialize ISAv3 MMU registers before
setting partition table"), introduced this problem because it zeroes
PIDR at boot. However previously the value was inherited from firmware
or kexec, which is not robust and can be zero (e.g., mambo).

Fixes: 371b80447f ("powerpc/64s: Initialize ISAv3 MMU registers before setting partition table")
Cc: stable@vger.kernel.org # v4.15+
Reported-by: Florian Weimer <fweimer@redhat.com>
Tested-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-08 23:56:11 +11:00
Nathan Fontenot
1d9a090783 powerpc/numa: Invalidate numa_cpu_lookup_table on cpu remove
When DLPAR removing a CPU, the unmapping of the cpu from a node in
unmap_cpu_from_node() should also invalidate the CPUs entry in the
numa_cpu_lookup_table. There is not a guarantee that on a subsequent
DLPAR add of the CPU the associativity will be the same and thus
could be in a different node. Invalidating the entry in the
numa_cpu_lookup_table causes the associativity to be read from the
device tree at the time of the add.

The current behavior of not invalidating the CPUs entry in the
numa_cpu_lookup_table can result in scenarios where the the topology
layout of CPUs in the partition does not match the device tree
or the topology reported by the HMC.

This bug looks like it was introduced in 2004 in the commit titled
"ppc64: cpu hotplug notifier for numa", which is 6b15e4e87e32 in the
linux-fullhist tree. Hence tag it for all stable releases.

Cc: stable@vger.kernel.org
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-08 23:56:10 +11:00
Ingo Molnar
8284507916 Merge branch 'linus' into sched/urgent, to resolve conflicts
Conflicts:
	arch/arm64/kernel/entry.S
	arch/x86/Kconfig
	include/linux/sched/mm.h
	kernel/fork.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-06 21:12:31 +01:00
Linus Torvalds
3ff1b28caa libnvdimm for 4.16
* Require struct page by default for filesystem DAX to remove a number of
   surprising failure cases.  This includes failures with direct I/O, gdb and
   fork(2).
 
 * Add support for the new Platform Capabilities Structure added to the NFIT in
   ACPI 6.2a.  This new table tells us whether the platform supports flushing
   of CPU and memory controller caches on unexpected power loss events.
 
 * Revamp vmem_altmap and dev_pagemap handling to clean up code and better
   support future future PCI P2P uses.
 
 * Deprecate the ND_IOCTL_SMART_THRESHOLD command whose payload has become
   out-of-sync with recent versions of the NVDIMM_FAMILY_INTEL spec, and
   instead rely on the generic ND_CMD_CALL approach used by the two other IOCTL
   families, NVDIMM_FAMILY_{HPE,MSFT}.
 
 * Enhance nfit_test so we can test some of the new things added in version 1.6
   of the DSM specification.  This includes testing firmware download and
   simulating the Last Shutdown State (LSS) status.
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Merge tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Ross Zwisler:

 - Require struct page by default for filesystem DAX to remove a number
   of surprising failure cases. This includes failures with direct I/O,
   gdb and fork(2).

 - Add support for the new Platform Capabilities Structure added to the
   NFIT in ACPI 6.2a. This new table tells us whether the platform
   supports flushing of CPU and memory controller caches on unexpected
   power loss events.

 - Revamp vmem_altmap and dev_pagemap handling to clean up code and
   better support future future PCI P2P uses.

 - Deprecate the ND_IOCTL_SMART_THRESHOLD command whose payload has
   become out-of-sync with recent versions of the NVDIMM_FAMILY_INTEL
   spec, and instead rely on the generic ND_CMD_CALL approach used by
   the two other IOCTL families, NVDIMM_FAMILY_{HPE,MSFT}.

 - Enhance nfit_test so we can test some of the new things added in
   version 1.6 of the DSM specification. This includes testing firmware
   download and simulating the Last Shutdown State (LSS) status.

* tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (37 commits)
  libnvdimm, namespace: remove redundant initialization of 'nd_mapping'
  acpi, nfit: fix register dimm error handling
  libnvdimm, namespace: make min namespace size 4K
  tools/testing/nvdimm: force nfit_test to depend on instrumented modules
  libnvdimm/nfit_test: adding support for unit testing enable LSS status
  libnvdimm/nfit_test: add firmware download emulation
  nfit-test: Add platform cap support from ACPI 6.2a to test
  libnvdimm: expose platform persistence attribute for nd_region
  acpi: nfit: add persistent memory control flag for nd_region
  acpi: nfit: Add support for detect platform CPU cache flush on power loss
  device-dax: Fix trailing semicolon
  libnvdimm, btt: fix uninitialized err_lock
  dax: require 'struct page' by default for filesystem dax
  ext2: auto disable dax instead of failing mount
  ext4: auto disable dax instead of failing mount
  mm, dax: introduce pfn_t_special()
  mm: Fix devm_memremap_pages() collision handling
  mm: Fix memory size alignment in devm_memremap_pages_release()
  memremap: merge find_dev_pagemap into get_dev_pagemap
  memremap: change devm_memremap_pages interface to use struct dev_pagemap
  ...
2018-02-06 10:41:33 -08:00
Mathieu Desnoyers
3ccfebedd8 powerpc, membarrier: Skip memory barrier in switch_mm()
Allow PowerPC to skip the full memory barrier in switch_mm(), and
only issue the barrier when scheduling into a task belonging to a
process that has registered to use expedited private.

Threads targeting the same VM but which belong to different thread
groups is a tricky case. It has a few consequences:

It turns out that we cannot rely on get_nr_threads(p) to count the
number of threads using a VM. We can use
(atomic_read(&mm->mm_users) == 1 && get_nr_threads(p) == 1)
instead to skip the synchronize_sched() for cases where the VM only has
a single user, and that user only has a single thread.

It also turns out that we cannot use for_each_thread() to set
thread flags in all threads using a VM, as it only iterates on the
thread group.

Therefore, test the membarrier state variable directly rather than
relying on thread flags. This means
membarrier_register_private_expedited() needs to set the
MEMBARRIER_STATE_PRIVATE_EXPEDITED flag, issue synchronize_sched(), and
only then set MEMBARRIER_STATE_PRIVATE_EXPEDITED_READY which allows
private expedited membarrier commands to succeed.
membarrier_arch_switch_mm() now tests for the
MEMBARRIER_STATE_PRIVATE_EXPEDITED flag.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Parri <parri.andrea@gmail.com>
Cc: Andrew Hunter <ahh@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Avi Kivity <avi@scylladb.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Dave Watson <davejwatson@fb.com>
Cc: David Sehr <sehr@google.com>
Cc: Greg Hackmann <ghackmann@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maged Michael <maged.michael@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-api@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20180129202020.8515-3-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-05 21:34:02 +01:00
Ross Zwisler
ee95f4059a Merge branch 'for-4.16/nfit' into libnvdimm-for-next 2018-02-03 00:26:26 -07:00
Linus Torvalds
03f51d4efa powerpc updates for 4.16
Highlights:
 
  - Enable support for memory protection keys aka "pkeys" on Power7/8/9 when
    using the hash table MMU.
 
  - Extend our interrupt soft masking to support masking PMU interrupts as well
    as "normal" interrupts, and then use that to implement local_t for a ~4x
    speedup vs the current atomics-based implementation.
 
  - A new driver "ocxl" for "Open Coherent Accelerator Processor Interface
    (OpenCAPI)" devices.
 
  - Support for new device tree properties on PowerVM to describe hotpluggable
    memory and devices.
 
  - Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 64-bit VDSO.
 
  - Freescale updates from Scott:
      "Contains fixes for CPM GPIO and an FSL PCI erratum workaround, plus a
       minor cleanup patch."
 
 As well as quite a lot of other changes all over the place, and small fixes and
 cleanups as always.
 
 Thanks to:
   Alan Modra, Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andreas
   Schwab, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman
   Khandual, Anton Blanchard, Arnd Bergmann, Balbir Singh, Benjamin
   Herrenschmidt, Bhaktipriya Shridhar, Bryant G. Ly, Cédric Le Goater,
   Christophe Leroy, Christophe Lombard, Cyril Bur, David Gibson, Desnes A. Nunes
   do Rosario, Dmitry Torokhov, Frederic Barrat, Geert Uytterhoeven, Guilherme G.
   Piccoli, Gustavo A. R. Silva, Gustavo Romero, Ivan Mikhaylov, Joakim
   Tjernlund, Joe Perches, Josh Poimboeuf, Juan J. Alvarez, Julia Cartwright,
   Kamalesh Babulal, Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre,
   Michael Bringmann, Michael Hanselmann, Michael Neuling, Nathan Fontenot,
   Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Philippe Bergheaud, Ram Pai,
   Russell Currey, Santosh Sivaraj, Scott Wood, Seth Forshee, Simon Guo, Stewart
   Smith, Sukadev Bhattiprolu, Thiago Jung Bauermann, Vaibhav Jain, Vasyl
   Gomonovych.
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Merge tag 'powerpc-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights:

   - Enable support for memory protection keys aka "pkeys" on Power7/8/9
     when using the hash table MMU.

   - Extend our interrupt soft masking to support masking PMU interrupts
     as well as "normal" interrupts, and then use that to implement
     local_t for a ~4x speedup vs the current atomics-based
     implementation.

   - A new driver "ocxl" for "Open Coherent Accelerator Processor
     Interface (OpenCAPI)" devices.

   - Support for new device tree properties on PowerVM to describe
     hotpluggable memory and devices.

   - Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 64-bit
     VDSO.

   - Freescale updates from Scott: fixes for CPM GPIO and an FSL PCI
     erratum workaround, plus a minor cleanup patch.

  As well as quite a lot of other changes all over the place, and small
  fixes and cleanups as always.

  Thanks to: Alan Modra, Alastair D'Silva, Alexey Kardashevskiy,
  Alistair Popple, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V,
  Anju T Sudhakar, Anshuman Khandual, Anton Blanchard, Arnd Bergmann,
  Balbir Singh, Benjamin Herrenschmidt, Bhaktipriya Shridhar, Bryant G.
  Ly, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Cyril Bur,
  David Gibson, Desnes A. Nunes do Rosario, Dmitry Torokhov, Frederic
  Barrat, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo A. R. Silva,
  Gustavo Romero, Ivan Mikhaylov, Joakim Tjernlund, Joe Perches, Josh
  Poimboeuf, Juan J. Alvarez, Julia Cartwright, Kamalesh Babulal,
  Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael
  Bringmann, Michael Hanselmann, Michael Neuling, Nathan Fontenot,
  Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Philippe Bergheaud,
  Ram Pai, Russell Currey, Santosh Sivaraj, Scott Wood, Seth Forshee,
  Simon Guo, Stewart Smith, Sukadev Bhattiprolu, Thiago Jung Bauermann,
  Vaibhav Jain, Vasyl Gomonovych"

* tag 'powerpc-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (199 commits)
  powerpc/mm/radix: Fix build error when RADIX_MMU=n
  macintosh/ams-input: Use true and false for boolean values
  macintosh: change some data types from int to bool
  powerpc/watchdog: Print the NIP in soft_nmi_interrupt()
  powerpc/watchdog: regs can't be null in soft_nmi_interrupt()
  powerpc/watchdog: Tweak watchdog printks
  powerpc/cell: Remove axonram driver
  rtc-opal: Fix handling of firmware error codes, prevent busy loops
  powerpc/mpc52xx_gpt: make use of raw_spinlock variants
  macintosh/adb: Properly mark continued kernel messages
  powerpc/pseries: Fix cpu hotplug crash with memoryless nodes
  powerpc/numa: Ensure nodes initialized for hotplug
  powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes
  powerpc/kernel: Block interrupts when updating TIDR
  powerpc/powernv/idoa: Remove unnecessary pcidev from pci_dn
  powerpc/mm/nohash: do not flush the entire mm when range is a single page
  powerpc/pseries: Add Initialization of VF Bars
  powerpc/pseries/pci: Associate PEs to VFs in configure SR-IOV
  powerpc/eeh: Add EEH notify resume sysfs
  powerpc/eeh: Add EEH operations to notify resume
  ...
2018-02-02 10:01:04 -08:00
Aneesh Kumar K.V
423ac9af3c mm/thp: remove pmd_huge_split_prepare()
Instead of marking the pmd ready for split, invalidate the pmd.  This
should take care of powerpc requirement.  Only side effect is that we
mark the pmd invalid early.  This can result in us blocking access to
the page a bit longer if we race against a thp split.

[kirill.shutemov@linux.intel.com: rebased, dirty THP once]
Link: http://lkml.kernel.org/r/20171213105756.69879-13-kirill.shutemov@linux.intel.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Daney <david.daney@cavium.com>
Cc: David Miller <davem@davemloft.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Nitin Gupta <nitin.m.gupta@oracle.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-31 17:18:38 -08:00
Aneesh Kumar K.V
8cc931e033 powerpc/mm: update pmdp_invalidate to return old pmd value
It's required to avoid losing dirty and accessed bits.

Link: http://lkml.kernel.org/r/20171213105756.69879-7-kirill.shutemov@linux.intel.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-31 17:18:37 -08:00
Michael Bringmann
e67e02a544 powerpc/pseries: Fix cpu hotplug crash with memoryless nodes
On powerpc systems with shared configurations of CPUs and memory and
memoryless nodes at boot, an event ordering problem was observed on a
SLES12 build platforms with the hot-add of CPUs to the memoryless
nodes.

* The most common error occurred when the memory SLAB driver attempted
  to reference the memoryless node to which a CPU was being added
  before the kernel had finished initializing all of the data
  structures for the CPU and exited 'device_online' under
  DLPAR/hot-add.

  Normally the memoryless node would be initialized through the call
  path device_online ... arch_update_cpu_topology ... find_cpu_nid ...
  try_online_node. This patch ensures that the powerpc node will be
  initialized as early as possible, even if it was memoryless and
  CPU-less at the point when we are trying to hot-add a new CPU to it.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-27 20:59:45 +11:00
Michael Bringmann
ea05ba7c55 powerpc/numa: Ensure nodes initialized for hotplug
This patch fixes some problems encountered at runtime with
configurations that support memory-less nodes, or that hot-add CPUs
into nodes that are memoryless during system execution after boot. The
problems of interest include:

* Nodes known to powerpc to be memoryless at boot, but to have CPUs in
  them are allowed to be 'possible' and 'online'. Memory allocations
  for those nodes are taken from another node that does have memory
  until and if memory is hot-added to the node.

* Nodes which have no resources assigned at boot, but which may still
  be referenced subsequently by affinity or associativity attributes,
  are kept in the list of 'possible' nodes for powerpc. Hot-add of
  memory or CPUs to the system can reference these nodes and bring
  them online instead of redirecting the references to one of the set
  of nodes known to have memory at boot.

Note that this software operates under the context of CPU hotplug. We
are not doing memory hotplug in this code, but rather updating the
kernel's CPU topology (i.e. arch_update_cpu_topology /
numa_update_cpu_topology). We are initializing a node that may be used
by CPUs or memory before it can be referenced as invalid by a CPU
hotplug operation. CPU hotplug operations are protected by a range of
APIs including cpu_maps_update_begin/cpu_maps_update_done,
cpus_read/write_lock / cpus_read/write_unlock, device locks, and more.
Memory hotplug operations, including try_online_node, are protected by
mem_hotplug_begin/mem_hotplug_done, device locks, and more. In the
case of CPUs being hot-added to a previously memoryless node, the
try_online_node operation occurs wholly within the CPU locks with no
overlap. Using HMC hot-add/hot-remove operations, we have been able to
add and remove CPUs to any possible node without failures. HMC
operations involve a degree self-serialization, though.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-27 20:59:02 +11:00
Michael Bringmann
a346137e91 powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes
On powerpc systems which allow 'hot-add' of CPU or memory resources,
it may occur that the new resources are to be inserted into nodes that
were not used for these resources at bootup. In the kernel, any node
that is used must be defined and initialized. These empty nodes may
occur when,

* Dedicated vs. shared resources. Shared resources require information
  such as the VPHN hcall for CPU assignment to nodes. Associativity
  decisions made based on dedicated resource rules, such as
  associativity properties in the device tree, may vary from decisions
  made using the values returned by the VPHN hcall.

* memoryless nodes at boot. Nodes need to be defined as 'possible' at
  boot for operation with other code modules. Previously, the powerpc
  code would limit the set of possible nodes to those which have
  memory assigned at boot, and were thus online. Subsequent add/remove
  of CPUs or memory would only work with this subset of possible
  nodes.

* memoryless nodes with CPUs at boot. Due to the previous restriction
  on nodes, nodes that had CPUs but no memory were being collapsed
  into other nodes that did have memory at boot. In practice this
  meant that the node assignment presented by the runtime kernel
  differed from the affinity and associativity attributes presented by
  the device tree or VPHN hcalls. Nodes that might be known to the
  pHyp were not 'possible' in the runtime kernel because they did not
  have memory at boot.

This patch ensures that sufficient nodes are defined to support
configuration requirements after boot, as well as at boot. This patch
set fixes a couple of problems.

* Nodes known to powerpc to be memoryless at boot, but to have CPUs in
  them are allowed to be 'possible' and 'online'. Memory allocations
  for those nodes are taken from another node that does have memory
  until and if memory is hot-added to the node. * Nodes which have no
  resources assigned at boot, but which may still be referenced
  subsequently by affinity or associativity attributes, are kept in
  the list of 'possible' nodes for powerpc. Hot-add of memory or CPUs
  to the system can reference these nodes and bring them online
  instead of redirecting to one of the set of nodes that were known to
  have memory at boot.

This patch extracts the value of the lowest domain level (number of
allocable resources) from the device tree property
"ibm,max-associativity-domains" to use as the maximum number of nodes
to setup as possibly available in the system. This new setting will
override the instruction:

    nodes_and(node_possible_map, node_possible_map, node_online_map);

presently seen in the function arch/powerpc/mm/numa.c:initmem_init().

If the "ibm,max-associativity-domains" property is not present at
boot, no operation will be performed to define or enable additional
nodes, or enable the above 'nodes_and()'.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-27 20:55:02 +11:00
Christophe Leroy
5c8136fa1a powerpc/mm/nohash: do not flush the entire mm when range is a single page
Most of the time, flush_tlb_range() is called on single pages.
At the time being, flush_tlb_range() inconditionnaly calls
flush_tlb_mm() which flushes at least the entire PID pages and on
older CPUs like 4xx or 8xx it flushes the entire TLB table.

This patch calls flush_tlb_page() instead of flush_tlb_mm() when
the range is a single page.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-27 20:24:44 +11:00
Mahesh Salgaonkar
8d81296cfc powerpc/radix: Remove trace_tlbie call from radix__flush_tlb_all
radix__flush_tlb_all() is called only in kexec path in real mode and any
tracepoints at this stage will make kexec to fail if enabled.

To verify enable tlbie trace before kexec.

$ echo 1 > /sys/kernel/debug/tracing/events/powerpc/tlbie/enable
== kexec into new kernel and kexec fails.

Fix this by not calling trace_tlbie from radix__flush_tlb_all().

Fixes: 0428491cba ("powerpc/mm: Trace tlbie(l) instructions")
Cc: stable@vger.kernel.org # v4.13+
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-22 05:48:35 +11:00
David Gibson
7339390d77 powerpc/pseries: Don't give a warning when HPT resizing isn't available
As of 438cc81a41 "powerpc/pseries: Automatically resize HPT for memory hot
add/remove" when running on the pseries platform, we always attempt to
use the PAPR extension to resize the hashed page table (HPT) when we add
or remove memory.

This is fine, but when the extension is available we'll give a harmless,
but scary warning.  This patch suppresses the warning in this case.  It
will still warn if the feature is supposed to be available, but didn't
work.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-22 05:48:34 +11:00
Aneesh Kumar K.V
10527e8081 powerpc/hash: Skip non initialized page size in init_hpte_page_sizes
One of the easiest way to test config with 4K HPTE is to disable 64K hardware
page size like below.

int __init htab_dt_scan_page_sizes(unsigned long node,

 		size -= 3; prop += 3;
 		base_idx = get_idx_from_shift(base_shift);
-		if (base_idx < 0) {
+		if (base_idx < 0 || base_idx == MMU_PAGE_64K) {
 			/* skip the pte encoding also */
 			prop += lpnum * 2; size -= lpnum * 2;

But then this results in error in other part of the code such as MPSS parsing
where we look at 4K base page size and 64K actual page size support.

This patch fix MPSS parsing by ignoring the actual page sizes marked
unsupported. In reality this can happen only with a corrupt device tree. But it
is good to tighten the error check.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-21 23:37:42 +11:00
Michael Ellerman
ebf0b6a8b1 Merge branch 'fixes' into next
Merge our fixes branch from the 4.15 cycle.

Unusually the fixes branch saw some significant features merged,
notably the RFI flush patches, so we want the code in next to be
tested against that, to avoid any surprises when the two are merged.

There's also some other work on the panic handling that was reverted
in fixes and we now want to do properly in next, which would conflict.

And we also fix a few other minor merge conflicts.
2018-01-21 23:21:14 +11:00
Anshuman Khandual
5b2b807147 powerpc/mm: Invalidate subpage_prot() system call on radix platforms
Radix enabled platforms don't support subpage_prot() system calls. But
at present the system call goes through without an error and fails
later on while validating expected subpage accesses. Lets not allow
the system call on powerpc radix platforms to begin with to prevent
this confusion in user space.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-21 01:12:21 +11:00
Ram Pai
cf43d3b264 powerpc: Enable pkey subsystem
PAPR defines 'ibm,processor-storage-keys' property. It exports two
values. The first value holds the number of data-access keys and the
second holds the number of instruction-access keys. Due to a bug in
the firmware, instruction-access keys is always reported as zero.
However any key can be configured to disable data-access and/or
disable execution-access. The inavailablity of the second value is not
a big handicap, though it could have been used to determine if the
platform supported disable-execution-access.

Non-PAPR platforms do not define this property in the device tree yet.
Fortunately power8 is the only released Non-PAPR platform that is
supported. Here, we hardcode the number of supported pkey to 32, by
consulting the PowerISA3.0

This patch calculates the number of keys supported by the platform.
Also it determines the platform support for read/write/execution
access support for pkeys.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[mpe: Use a PVR check instead of CPU_FTR for execute. Restrict to
 Power7/8/9 for now until older CPUs are tested.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-21 01:06:10 +11:00
Ram Pai
99cd130232 powerpc: Deliver SEGV signal on pkey violation
The value of the pkey, whose protection got violated,
is made available in si_pkey field of the siginfo structure.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:05 +11:00
Ram Pai
087003e9ef powerpc: introduce get_mm_addr_key() helper
get_mm_addr_key() helper returns the pkey associated with
an address corresponding to a given mm_struct.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:05 +11:00
Ram Pai
e6c2a4797e powerpc: Handle exceptions caused by pkey violation
Handle Data and  Instruction exceptions caused by memory
protection-key.

The CPU will detect the key fault if the HPTE is already
programmed with the key.

However if the HPTE is not  hashed, a key fault will not
be detected by the hardware. The software will detect
pkey violation in such a case.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:04 +11:00
Ram Pai
1137573acf powerpc: implementation for arch_vma_access_permitted()
This patch provides the implementation for
arch_vma_access_permitted(). Returns true if the
requested access is allowed by pkey associated with the
vma.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:04 +11:00
Ram Pai
f2407ef3ba powerpc: helper to validate key-access permissions of a pte
helper function that checks if the read/write/execute is allowed
on the pte.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:03 +11:00
Ram Pai
a6590ca55f powerpc: Program HPTE key protection bits
Map the PTE protection key bits to the HPTE key protection bits,
while creating HPTE  entries.

Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:03 +11:00
Ram Pai
87bbabbed8 powerpc: implementation for arch_override_mprotect_pkey()
arch independent code calls arch_override_mprotect_pkey()
to return a pkey that best matches the requested protection.

This patch provides the implementation.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:02 +11:00
Ram Pai
013a91b39c powerpc: ability to associate pkey to a vma
arch-independent code expects the arch to  map
a  pkey  into the vma's protection bit setting.
The patch provides that ability.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:01 +11:00
Ram Pai
5586cf61e1 powerpc: introduce execute-only pkey
This patch provides the implementation of execute-only pkey.
The architecture-independent layer expects the arch-dependent
layer, to support the ability to create and enable a special
key which has execute-only permission.

Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:01 +11:00
Ram Pai
06bb53b338 powerpc: store and restore the pkey state across context switches
Store and restore the AMR, IAMR and UAMOR register state of the task
before scheduling out and after scheduling in, respectively.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:00 +11:00
Ram Pai
dcf872956d powerpc: ability to create execute-disabled pkeys
powerpc has hardware support to disable execute on a pkey.
This patch enables the ability to create execute-disabled
keys.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:00 +11:00
Ram Pai
2ddc53f3a7 powerpc: implementation for arch_set_user_pkey_access()
This patch provides the detailed implementation for
a user to allocate a key and enable it in the hardware.

It provides the plumbing, but it cannot be used till
the system call is implemented. The next patch  will
do so.

Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:58:59 +11:00
Ram Pai
4d70b698f9 powerpc: helper functions to initialize AMR, IAMR and UAMOR registers
Introduce  helper functions that can initialize the bits in the AMR,
IAMR and UAMOR register; the bits that correspond to the given pkey.

Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:58:58 +11:00
Ram Pai
1b4037dead powerpc: helper function to read, write AMR, IAMR, UAMOR registers
Implements helper functions to read and write the key related
registers; AMR, IAMR, UAMOR.

AMR register tracks the read,write permission of a key
IAMR register tracks the execute permission of a key
UAMOR register enables and disables a key

Acked-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:58:58 +11:00
Ram Pai
4fb158f65a powerpc: track allocation status of all pkeys
Total 32 keys are available on power7 and above. However
pkey 0,1 are reserved. So effectively we  have  30 pkeys.

On 4K kernels, we do not  have  5  bits  in  the  PTE to
represent  all the keys; we only have 3bits. Two of those
keys are reserved; pkey 0 and pkey 1. So effectively  we
have 6 pkeys.

This patch keeps track of reserved keys, allocated  keys
and keys that are currently free.

Also it  adds  skeletal  functions  and macros, that the
architecture-independent code expects to be available.

Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:58:35 +11:00
Ram Pai
92e3da3cf1 powerpc: initial pkey plumbing
Basic  plumbing  to   initialize  the   pkey  system.
Nothing is enabled yet. A later patch will enable it
once all the infrastructure is in place.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[mpe: Rework copyrights to use SPDX tags]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 21:45:03 +11:00
Madhavan Srinivasan
4e26bc4a4e powerpc/64: Rename soft_enabled to irq_soft_mask
Rename the paca->soft_enabled to paca->irq_soft_mask as it is no
longer used as a flag for interrupt state, but a mask.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:01 +11:00
Madhavan Srinivasan
c2e480ba82 powerpc/64: Add #defines for paca->soft_enabled flags
Two #defines IRQS_ENABLED and IRQS_DISABLED are added to be used when
updating paca->soft_enabled. Replace the hardcoded values used when
updating paca->soft_enabled with IRQ_(EN|DIS)ABLED #define. No logic
change.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:56 +11:00
Nicholas Piggin
c610d65c0a powerpc/pseries: lift RTAS limit for hash
With the previous patch to switch to 64-bit mode after returning from
RTAS and before doing any memory accesses, the RMA limit need not be
clamped to 1GB to avoid RTAS bugs.

Keep the 1GB limit for older firmware (although this is more of a kernel
concern than RTAS), and remove it starting with POWER9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:45:34 +11:00
Nicholas Piggin
5eae82cab5 powerpc/pseries: lift RTAS limit for radix
With the previous patch to switch to 64-bit mode after returning from
RTAS and before doing any memory accesses, the RMA limit need not be
clamped to 1GB to avoid RTAS bugs.

Keep the 1GB limit for older firmware (although this is more of a kernel
concern than RTAS), and remove it starting with POWER9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:44:42 +11:00
Nicholas Piggin
98ae0069cb powerpc/pseries: radix is not subject to RMA limit, remove it
The radix guest is not subject to the paravirtualized HPT VRMA limit,
so remove that from ppc64_rma_size calculation for that platform.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:42:14 +11:00
Nicholas Piggin
1513c33d71 powerpc/powernv: Remove real mode access limit for early allocations
This removes the RMA limit on powernv platform, which constrains
early allocations such as PACAs and stacks. There are still other
restrictions that must be followed, such as bolted SLB limits, but
real mode addressing has no constraints.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:41:44 +11:00
Nicholas Piggin
d4748276ae powerpc/64s: Improve local TLB flush for boot and MCE on POWER9
There are several cases outside the normal address space management
where a CPU's entire local TLB is to be flushed:

  1. Booting the kernel, in case something has left stale entries in
     the TLB (e.g., kexec).

  2. Machine check, to clean corrupted TLB entries.

One other place where the TLB is flushed, is waking from deep idle
states. The flush is a side-effect of calling ->cpu_restore with the
intention of re-setting various SPRs. The flush itself is unnecessary
because in the first case, the TLB should not acquire new corrupted
TLB entries as part of sleep/wake (though they may be lost).

This type of TLB flush is coded inflexibly, several times for each CPU
type, and they have a number of problems with ISA v3.0B:

- The current radix mode of the MMU is not taken into account, it is
  always done as a hash flushn For IS=2 (LPID-matching flush from host)
  and IS=3 with HV=0 (guest kernel flush), tlbie(l) is undefined if
  the R field does not match the current radix mode.

- ISA v3.0B hash must flush the partition and process table caches as
  well.

- ISA v3.0B radix must flush partition and process scoped translations,
  partition and process table caches, and also the page walk cache.

So consolidate the flushing code and implement it in C and inline asm
under the mm/ directory with the rest of the flush code. Add ISA v3.0B
cases for radix and hash, and use the radix flush in radix environment.

Provide a way for IS=2 (LPID flush) to specify the radix mode of the
partition. Have KVM pass in the radix mode of the guest.

Take out the flushes from early cputable/dt_cpu_ftrs detection hooks,
and move it later in the boot process after, the MMU registers are set
up and before relocation is first turned on.

The TLB flush is no longer called when restoring from deep idle states.
This was not be done as a separate step because booting secondaries
uses the same cpu_restore as idle restore, which needs the TLB flush.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:40:31 +11:00
Benjamin Herrenschmidt
2271db20e4 powerpc: Use the TRAP macro whenever comparing a trap number
Trap numbers can have extra bits at the bottom that need to
be filtered out. There are a few cases where we don't do that.

It's possible that we got lucky but better safe than sorry.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:51:43 +11:00
Christophe Leroy
4f94b2c746 powerpc/8xx: Use L1 entry APG to handle _PAGE_ACCESSED for CONFIG_SWAP
When CONFIG_SWAP is set, the TLB miss handlers have to also take
into account _PAGE_ACCESSED flag. At the moment it is done by
anding _PAGE_ACCESSED into _PAGE_PRESENT using 3 instructions.

This patch uses APG for handling _PAGE_ACCESSED, allowing to
just copy _PAGE_ACCESSED bit into APG field, hence reducing the
action to a single instruction.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:47:15 +11:00
Christophe Leroy
de0f938739 powerpc/8xx: Remove _PAGE_USER and handle user access at PMD level
As Linux kernel separates KERNEL and USER address spaces, there is
therefore no need to flag USER access at page level.

Today, the 8xx TLB handlers already handle user access in the L1 entry
through Access Protection Groups, it is then natural to move the user
access handling at PMD level once _PAGE_NA allows to handle PAGE_NONE
protection without _PAGE_USER

In the mean time, as we free up one bit in the PTE, we can use it to
include SPS (page size flag) in the PTE and avoid handling it at every
TLB miss hence removing special handling based on compiled page size.

For _PAGE_EXEC, we rework it to use PP PTE bits, avoiding the copy
of _PAGE_EXEC bit into the L1 entry. Unfortunatly we are not
able to put it at the correct location as it conflicts with
NA/RO/RW bits for data entries.

Upper bits of APG in L1 entry overlap with PMD base address. In
order to avoid having to filter that out, we set up all groups so that
upper bits can have any value.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:47:14 +11:00
Christophe Leroy
351750331f powerpc/mm: Introduce _PAGE_NA
Today, PAGE_NONE is defined as a page not having _PAGE_USER.
In some circunstances, when the CPU supports it, it might be
better to be able to flag a page with NO ACCESS.

In a following patch, the 8xx will switch user access being flagged
in the PMD, therefore it will not be possible anymore to use
_PAGE_USER as a way to flag a page with no access.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:47:14 +11:00
Christophe Leroy
812fadcb94 powerpc/mm: extend _PAGE_PRIVILEGED to all CPUs
commit ac29c64089 ("powerpc/mm: Replace _PAGE_USER with
_PAGE_PRIVILEGED") introduced _PAGE_PRIVILEGED for BOOK3S/64

This patch generalises _PAGE_PRIVILEGED for all CPUs, allowing
to have either _PAGE_PRIVILEGED or _PAGE_USER or both.

PPC_8xx has a _PAGE_SHARED flag which is set for and only for
all non user pages. Lets rename it _PAGE_PRIVILEGED to remove
confusion as it has nothing to do with Linux shared pages.

On BookE, there's a _PAGE_BAP_SR which has to be set for kernel
pages: defining _PAGE_PRIVILEGED as _PAGE_BAP_SR will make
this generic

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:47:13 +11:00
Nathan Fontenot
2b31e3aec1 powerpc/drmem: Add support for ibm, dynamic-memory-v2 property
The Power Hypervisor has introduced a new device tree format for
the property describing the dynamic reconfiguration LMBs for a system,
ibm,dynamic-memory-v2. This new format condenses the size of the
property, especially on large memory systems, by reporting sets
of LMBs that have the same properties (flags and associativity array
index).

This patch updates the powerpc/mm/drmem.c code to provide routines
that can parse the new device tree format during the walk_drmem_lmb*
routines used during boot, the creation of the LMB array, and updating
the device tree to create a new property in the proper format for
ibm,dynamic-memory-v2.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:26:29 +11:00
Nathan Fontenot
2c77721552 powerpc: Move of_drconf_cell struct to asm/drmem.h
Now that the powerpc code parses dynamic reconfiguration memory
LMB information from the LMB array and not the device tree
directly we can move the of_drconf_cell struct to drmem.h where
it fits better.

In addition, the struct is renamed to of_drconf_cell_v1 in
anticipation of upcoming support for version 2 of the dynamic
reconfiguration property and the members are typed as __be*
values to reflect how they exist in the device tree.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:26:29 +11:00
Nathan Fontenot
6195a5001f powerpc/pseries: Update memory hotplug code to use drmem LMB array
Update the pseries memory hotplug code to use the newly added
dynamic reconfiguration LMB array. Doing this is required for the
upcoming support of version 2 of the dynamic reconfiguration
device tree property.

In addition, making this change cleans up the code that parses the
LMB information as we no longer need to worry about device tree
format. This allows us to discard one of the first steps on memory
hotplug where we make a working copy of the device tree property and
convert the entire property to cpu format. Instead we just use the
LMB array directly while holding the memory hotplug lock.

This patch also moves the updating of the device tree property to
powerpc/mm/drmem.c. This allows to the hotplug code to work without
needing to know the device tree format and provides a single
routine for updating the device tree property. This new routine
will handle determination of the proper device tree format and
generate a properly formatted device tree property.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:26:28 +11:00
Nathan Fontenot
514a9cb331 powerpc/numa: Update numa code use walk_drmem_lmbs
Update code in powerpc/numa.c to use the walk_drmem_lmbs()
routine instead of parsing the device tree directly. This is
in anticipation of introducing a new ibm,dynamic-memory-v2
property with a different format. This will allow the numa code
to use a single initialization routine per-LMB irregardless of
the device tree format.

Additionally, to support additional routines in numa.c that need
to look up LMB information, an late_init routine is added to drmem.c
to allocate the array of LMB information. This LMB array will provide
per-LMB information to separate the LMB data from the device tree
format.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:26:28 +11:00
Nathan Fontenot
6c6ea53725 powerpc/mm: Separate ibm, dynamic-memory data from DT format
We currently have code to parse the dynamic reconfiguration LMB
information from the ibm,dynamic-meory device tree property in
multiple locations; numa.c, prom.c, and pseries/hotplug-memory.c.
In anticipation of adding support for a version 2 of the
ibm,dynamic-memory property this patch aims to separate the device
tree information from the device tree format.

Doing this requires a two step process to avoid a possibly very large
bootmem allocation early in boot. During initial boot, new routines
are provided to walk the device tree property and make a call-back
for each LMB.

The second step (introduced in later patches) will allocate an
array of LMB information that can be used directly without needing
to know the DT format.

This approach provides the benefit of consolidating the device tree
property parsing to a single location and (eventually) providing
a common data structure for retrieving LMB information.

This patch introduces a routine to walk the ibm,dynamic-memory
property in the flattened device tree and updates the prom.c code
to use this to initialize memory.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:26:27 +11:00
Nathan Fontenot
b88fc309d6 powerpc/numa: Look up associativity array in of_drconf_to_nid_single
Look up the associativity arrays in of_drconf_to_nid_single when
deriving the nid for a LMB instead of having it passed in as a
parameter.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 18:23:48 +11:00
Nathan Fontenot
22508f3dc9 powerpc/numa: Look up device node in of_get_usable_memory()
Look up the device node for the usable memory property instead
of having it passed in as a parameter. This changes precedes an update
in which the calling routines for of_get_usable_memory() will not have
the device node pointer to pass in.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 18:23:48 +11:00
Nathan Fontenot
35f80debae powerpc/numa: Look up device node in of_get_assoc_arrays()
Look up the device node for the associativity array property instead
of having it passed in as a parameter. This changes precedes an update
in which the calling routines for of_get_assoc_arrays() will not have
the device node pointer to pass in.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 18:23:47 +11:00
Christoph Hellwig
a8fc357b28 mm: split altmap memory map allocation from normal case
No functional changes, just untangling the call chain and document
why the altmap is passed around the hotplug code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig
24b6d41643 mm: pass the vmem_altmap to vmemmap_free
We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig
da024512a1 mm: pass the vmem_altmap to arch_remove_memory and __remove_pages
We can just pass this on instead of having to do a radix tree lookup
without proper locking 2 levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig
7b73d978a5 mm: pass the vmem_altmap to vmemmap_populate
We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig
24e6d5a59a mm: pass the vmem_altmap to arch_add_memory and __add_pages
We can just pass this on instead of having to do a radix tree lookup
without proper locking 2 levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
John Sperbeck
ecb101aed8 powerpc/mm: Fix SEGV on mapped region to return SEGV_ACCERR
The recent refactoring of the powerpc page fault handler in commit
c3350602e8 ("powerpc/mm: Make bad_area* helper functions") caused
access to protected memory regions to indicate SEGV_MAPERR instead of
the traditional SEGV_ACCERR in the si_code field of a user-space
signal handler. This can confuse debug libraries that temporarily
change the protection of memory regions, and expect to use SEGV_ACCERR
as an indication to restore access to a region.

This commit restores the previous behavior. The following program
exhibits the issue:

    $ ./repro read  || echo "FAILED"
    $ ./repro write || echo "FAILED"
    $ ./repro exec  || echo "FAILED"

    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <unistd.h>
    #include <signal.h>
    #include <sys/mman.h>
    #include <assert.h>

    static void segv_handler(int n, siginfo_t *info, void *arg) {
            _exit(info->si_code == SEGV_ACCERR ? 0 : 1);
    }

    int main(int argc, char **argv)
    {
            void *p = NULL;
            struct sigaction act = {
                    .sa_sigaction = segv_handler,
                    .sa_flags = SA_SIGINFO,
            };

            assert(argc == 2);
            p = mmap(NULL, getpagesize(),
                    (strcmp(argv[1], "write") == 0) ? PROT_READ : 0,
                    MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
            assert(p != MAP_FAILED);

            assert(sigaction(SIGSEGV, &act, NULL) == 0);
            if (strcmp(argv[1], "read") == 0)
                    printf("%c", *(unsigned char *)p);
            else if (strcmp(argv[1], "write") == 0)
                    *(unsigned char *)p = 0;
            else if (strcmp(argv[1], "exec") == 0)
                    ((void (*)(void))p)();
            return 1;  /* failed to generate SEGV */
    }

Fixes: c3350602e8 ("powerpc/mm: Make bad_area* helper functions")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: John Sperbeck <jsperbeck@google.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Add commit references in change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-02 21:12:33 +11:00
Aneesh Kumar K.V
5fa5b16be5 powerpc/mm/hugetlb: Use pte_access_permitted for hugetlb access check
No functional change in this patch. This update gup_hugepte to use the
helper. This will help later when we add memory keys.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-22 22:28:31 +11:00
Ram Pai
7e4363550c powerpc: capture the PTE format changes in the dump pte report
The H_PAGE_F_SECOND,H_PAGE_F_GIX are not in the 64K main-PTE.
capture these changes in the dump pte report.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-20 18:57:26 +11:00
Ram Pai
a854868646 powerpc: use helper functions to get and set hash slots
replace redundant code in __hash_page_4K() and flush_hash_page()
with helper functions pte_get_hash_gslot() and pte_set_hidx()

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-20 18:57:25 +11:00
Ram Pai
bf9a95f9a6 powerpc: Free up four 64K PTE bits in 64K backed HPTE pages
Rearrange 64K PTE bits to free up bits 3, 4, 5 and 6
in the 64K backed HPTE pages. This along with the earlier
patch will entirely free up the four bits from 64K PTE.
The bit numbers are big-endian as defined in the ISA3.0

This patch does the following change to 64K PTE backed
by 64K HPTE.

H_PAGE_F_SECOND (S) which occupied bit 4 moves to the
	second part of the pte to bit 60.
H_PAGE_F_GIX (G,I,X) which occupied bit 5, 6 and 7 also
	moves to the second part of the pte to bit 61,
 	62, 63, 64 respectively

since bit 7 is now freed up, we move H_PAGE_BUSY (B) from
bit 9 to bit 7.

The second part of the PTE will hold
(H_PAGE_F_SECOND|H_PAGE_F_GIX) at bit 60,61,62,63.
NOTE: None of the bits in the secondary PTE were not used
by 64k-HPTE backed PTE.

Before the patch, the 64K HPTE backed 64k PTE format was
as follows

 0 1 2 3 4  5  6  7  8 9 10...........................63
 : : : : :  :  :  :  : : :                            :
 v v v v v  v  v  v  v v v                            v

,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-,
|x|x|x| |S |G |I |X |x|B| |x|x|................|x|x|x|x| <- primary pte
'_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_'
| | | | |  |  |  |  | | | | |..................| | | | | <- secondary pte
'_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_'

After the patch, the 64k HPTE backed 64k PTE format is
as follows

 0 1 2 3 4  5  6  7  8 9 10...........................63
 : : : : :  :  :  :  : : :                            :
 v v v v v  v  v  v  v v v                            v

,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-,
|x|x|x| |  |  |  |B |x| | |x|x|................|.|.|.|.| <- primary pte
'_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_'
| | | | |  |  |  |  | | | | |..................|S|G|I|X| <- secondary pte
'_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_'

The above PTE changes is applicable to hugetlbpages aswell.

The patch does the following code changes:

a) moves the H_PAGE_F_SECOND and H_PAGE_F_GIX to 4k PTE
	header since it is no more needed b the 64k PTEs.
b) abstracts out __real_pte() and __rpte_to_hidx() so the
	caller need not know the bit location of the slot.
c) moves the slot bits to the secondary pte.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-20 18:57:22 +11:00
Ram Pai
9d2edb1848 powerpc: Free up four 64K PTE bits in 4K backed HPTE pages
Rearrange 64K PTE bits to free up bits 3, 4, 5 and 6,
in the 4K backed HPTE pages.These bits continue to be used
for 64K backed HPTE pages in this patch, but will be freed
up in the next patch. The bit numbers are big-endian as
defined in the ISA3.0

The patch does the following change to the 4k HTPE backed
64K PTE's format.

H_PAGE_BUSY moves from bit 3 to bit 9 (B bit in the figure
		below)
V0 which occupied bit 4 is not used anymore.
V1 which occupied bit 5 is not used anymore.
V2 which occupied bit 6 is not used anymore.
V3 which occupied bit 7 is not used anymore.

Before the patch, the 4k backed 64k PTE format was as follows

 0 1 2 3 4  5  6  7  8 9 10...........................63
 : : : : :  :  :  :  : : :                            :
 v v v v v  v  v  v  v v v                            v

,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-,
|x|x|x|B|V0|V1|V2|V3|x| | |x|x|................|x|x|x|x| <- primary pte
'_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_'
|S|G|I|X|S |G |I |X |S|G|I|X|..................|S|G|I|X| <- secondary pte
'_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_'

After the patch, the 4k backed 64k PTE format is as follows

 0 1 2 3 4  5  6  7  8 9 10...........................63
 : : : : :  :  :  :  : : :                            :
 v v v v v  v  v  v  v v v                            v

,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-,
|x|x|x| |  |  |  |  |x|B| |x|x|................|.|.|.|.| <- primary pte
'_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_'
|S|G|I|X|S |G |I |X |S|G|I|X|..................|S|G|I|X| <- secondary pte
'_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_'

the four bits S,G,I,X (one quadruplet per 4k HPTE) that
cache the hash-bucket slot value, is initialized to
1,1,1,1 indicating -- an invalid slot. If a HPTE gets
cached in a 1111 slot(i.e 7th slot of secondary hash
bucket), it is released immediately. In other words,
even though 1111 is a valid slot value in the hash
bucket, we consider it invalid and release the slot and
the HPTE. This gives us the opportunity to determine
the validity of S,G,I,X bits based on its contents and
not on any of the bits V0,V1,V2 or V3 in the primary PTE

When we release a HPTE cached in the 1111 slot
we also release a legitimate slot in the primary
hash bucket and unmap its corresponding HPTE. This
is to ensure that we do get a HPTE cached in a slot
of the primary hash bucket, the next time we retry.

Though treating 1111 slot as invalid, reduces the
number of available slots in the hash bucket and may
have an effect on the performance, the probabilty of
hitting a 1111 slot is extermely low.

Compared to the current scheme, the above scheme
reduces the number of false hash table updates
significantly and has the added advantage of releasing
four valuable PTE bits for other purpose.

NOTE:even though bits 3, 4, 5, 6, 7 are not used when
the 64K PTE is backed by 4k HPTE, they continue to be
used if the PTE gets backed by 64k HPTE. The next
patch will decouple that aswell, and truely release the
bits.

This idea was jointly developed by Paul Mackerras,
Aneesh, Michael Ellermen and myself.

4K PTE format remains unchanged currently.

The patch does the following code changes
a) PTE flags are split between 64k and 4k header files.
b) __hash_page_4K() is reimplemented to reflect the
 above logic.

Acked-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-20 18:57:20 +11:00
Ram Pai
318995b4f5 powerpc: introduce pte_get_hash_gslot() helper
Introduce pte_get_hash_gslot()() which returns the global slot number of
the HPTE in the global hash table.

This function will come in handy as we work towards re-arranging the PTE
bits in the later patches.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-20 18:57:19 +11:00
Joe Perches
f2c2cbcc35 powerpc: Use pr_warn instead of pr_warning
At some point, pr_warning will be removed so all logging messages use
a consistent <prefix>_warn style.

Update arch/powerpc/

Miscellanea:

o Coalesce formats
o Realign arguments
o Use %s, __func__ instead of embedded function names
o Remove unnecessary line continuations

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Geoff Levand <geoff@infradead.org>
[mpe: Rebase due to some %pOF changes.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-04 11:54:34 +11:00
Linus Torvalds
a0651c7fa2 powerpc fixes for 4.15 #3
Two fixes for nasty kexec/kdump crashes in certain configurations.
 
 A couple of minor fixes for the new TIDR code.
 
 A fix for an oops in a CXL error handling path.
 
 Thanks to:
   Andrew Donnellan, Christophe Lombard, David Gibson, Mahesh Salgaonkar, Vaibhav Jain.
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Merge tag 'powerpc-4.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Two fixes for nasty kexec/kdump crashes in certain configurations.

  A couple of minor fixes for the new TIDR code.

  A fix for an oops in a CXL error handling path.

  Thanks to: Andrew Donnellan, Christophe Lombard, David Gibson, Mahesh
  Salgaonkar, Vaibhav Jain"

* tag 'powerpc-4.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc: Do not assign thread.tidr if already assigned
  powerpc: Avoid signed to unsigned conversion in set_thread_tidr()
  powerpc/kexec: Fix kexec/kdump in P9 guest kernels
  powerpc/powernv: Fix kexec crashes caused by tlbie tracing
  cxl: Check if vphb exists before iterating over AFU devices
2017-12-01 08:40:17 -05:00
Linus Torvalds
83ada03196 powerpc fixes for 4.15 #2
A small batch of fixes, about 50% tagged for stable and the rest for recently
 merged code.
 
 There's one more fix for the >128T handling on hash. Once a process had
 requested a single mmap above 128T we would then always search above 128T. The
 correct behaviour is to consider the hint address in isolation for each mmap
 request.
 
 Then a couple of fixes for the IMC PMU, a missing EXPORT_SYMBOL in VAS, a fix
 for STRICT_KERNEL_RWX on 32-bit, and a fix to correctly identify P9 DD2.1 but in
 code that is currently not used by default.
 
 Thanks to:
   Aneesh Kumar K.V, Christophe Leroy, Madhavan Srinivasan, Sukadev Bhattiprolu.
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Merge tag 'powerpc-4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "A small batch of fixes, about 50% tagged for stable and the rest for
  recently merged code.

  There's one more fix for the >128T handling on hash. Once a process
  had requested a single mmap above 128T we would then always search
  above 128T. The correct behaviour is to consider the hint address in
  isolation for each mmap request.

  Then a couple of fixes for the IMC PMU, a missing EXPORT_SYMBOL in
  VAS, a fix for STRICT_KERNEL_RWX on 32-bit, and a fix to correctly
  identify P9 DD2.1 but in code that is currently not used by default.

  Thanks to: Aneesh Kumar K.V, Christophe Leroy, Madhavan Srinivasan,
  Sukadev Bhattiprolu"

* tag 'powerpc-4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Fix Power9 DD2.1 logic in DT CPU features
  powerpc/perf: Fix IMC_MAX_PMU macro
  powerpc/perf: Fix pmu_count to count only nest imc pmus
  powerpc: Fix boot on BOOK3S_32 with CONFIG_STRICT_KERNEL_RWX
  powerpc/perf/imc: Use cpu_to_node() not topology_physical_package_id()
  powerpc/vas: Export chip_to_vas_id()
  powerpc/64s/slice: Use addr limit when computing slice mask
2017-11-24 19:40:12 -10:00
Mahesh Salgaonkar
a3961f824c powerpc/powernv: Fix kexec crashes caused by tlbie tracing
Rebooting into a new kernel with kexec fails in trace_tlbie() which is
called from native_hpte_clear(). This happens if the running kernel
has CONFIG_LOCKDEP enabled. With lockdep enabled, the tracepoints
always execute few RCU checks regardless of whether tracing is on or
off. We are already in the last phase of kexec sequence in real mode
with HILE_BE set. At this point the RCU check ends up in
RCU_LOCKDEP_WARN and causes kexec to fail.

Fix this by not calling trace_tlbie() from native_hpte_clear().

mpe: It's not safe to call trace points at this point in the kexec
path, even if we could avoid the RCU checks/warnings. The only
solution is to not call them.

Fixes: 0428491cba ("powerpc/mm: Trace tlbie(l) instructions")
Cc: stable@vger.kernel.org # v4.13+
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-23 23:10:14 +11:00
Aneesh Kumar K.V
7a06c66835 powerpc/64s/slice: Use addr limit when computing slice mask
While computing slice mask for the free area we need make sure we only
search in the addr limit applicable for this mmap. We update the
slb_addr_limit after we request for a mmap above 128TB. But the
following mmap request with hint addr below 128TB should still limit
its search to below 128TB. ie. we should not use slb_addr_limit to
compute slice mask in this case. Instead, we should derive high addr
limit based on the mmap hint addr value.

Fixes: f4ea6dcb08 ("powerpc/mm: Enable mappings above 128TB")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-20 19:28:25 +11:00
Linus Torvalds
5b0e2cb020 powerpc updates for 4.15
Non-highlights:
 
  - Five fixes for the >128T address space handling, both to fix bugs in our
    implementation and to bring the semantics exactly into line with x86.
 
 Highlights:
 
  - Support for a new OPAL call on bare metal machines which gives us a true NMI
    (ie. is not masked by MSR[EE]=0) for debugging etc.
 
  - Support for Power9 DD2 in the CXL driver.
 
  - Improvements to machine check handling so that uncorrectable errors can be
    reported into the generic memory_failure() machinery.
 
  - Some fixes and improvements for VPHN, which is used under PowerVM to notify
    the Linux partition of topology changes.
 
  - Plumbing to enable TM (transactional memory) without suspend on some Power9
    processors (PPC_FEATURE2_HTM_NO_SUSPEND).
 
  - Support for emulating vector loads form cache-inhibited memory, on some
    Power9 revisions.
 
  - Disable the fast-endian switch "syscall" by default (behind a CONFIG), we
    believe it has never had any users.
 
  - A major rework of the API drivers use when initiating and waiting for long
    running operations performed by OPAL firmware, and changes to the
    powernv_flash driver to use the new API.
 
  - Several fixes for the handling of FP/VMX/VSX while processes are using
    transactional memory.
 
  - Optimisations of TLB range flushes when using the radix MMU on Power9.
 
  - Improvements to the VAS facility used to access coprocessors on Power9, and
    related improvements to the way the NX crypto driver handles requests.
 
  - Implementation of PMEM_API and UACCESS_FLUSHCACHE for 64-bit.
 
 Thanks to:
   Alexey Kardashevskiy, Alistair Popple, Allen Pais, Andrew Donnellan, Aneesh
   Kumar K.V, Arnd Bergmann, Balbir Singh, Benjamin Herrenschmidt, Breno Leitao,
   Christophe Leroy, Christophe Lombard, Cyril Bur, Frederic Barrat, Gautham R.
   Shenoy, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo Romero, Haren
   Myneni, Joel Stanley, Kamalesh Babulal, Kautuk Consul, Markus Elfring, Masami
   Hiramatsu, Michael Bringmann, Michael Neuling, Michal Suchanek, Naveen N. Rao,
   Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pedro Miraglia Franco de
   Carvalho, Philippe Bergheaud, Sandipan Das, Seth Forshee, Shriya, Stephen
   Rothwell, Stewart Smith, Sukadev Bhattiprolu, Tyrel Datwyler, Vaibhav Jain,
   Vaidyanathan Srinivasan, William A. Kennington III.
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Merge tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "A bit of a small release, I suspect in part due to me travelling for
  KS. But my backlog of patches to review is smaller than usual, so I
  think in part folks just didn't send as much this cycle.

  Non-highlights:

   - Five fixes for the >128T address space handling, both to fix bugs
     in our implementation and to bring the semantics exactly into line
     with x86.

  Highlights:

   - Support for a new OPAL call on bare metal machines which gives us a
     true NMI (ie. is not masked by MSR[EE]=0) for debugging etc.

   - Support for Power9 DD2 in the CXL driver.

   - Improvements to machine check handling so that uncorrectable errors
     can be reported into the generic memory_failure() machinery.

   - Some fixes and improvements for VPHN, which is used under PowerVM
     to notify the Linux partition of topology changes.

   - Plumbing to enable TM (transactional memory) without suspend on
     some Power9 processors (PPC_FEATURE2_HTM_NO_SUSPEND).

   - Support for emulating vector loads form cache-inhibited memory, on
     some Power9 revisions.

   - Disable the fast-endian switch "syscall" by default (behind a
     CONFIG), we believe it has never had any users.

   - A major rework of the API drivers use when initiating and waiting
     for long running operations performed by OPAL firmware, and changes
     to the powernv_flash driver to use the new API.

   - Several fixes for the handling of FP/VMX/VSX while processes are
     using transactional memory.

   - Optimisations of TLB range flushes when using the radix MMU on
     Power9.

   - Improvements to the VAS facility used to access coprocessors on
     Power9, and related improvements to the way the NX crypto driver
     handles requests.

   - Implementation of PMEM_API and UACCESS_FLUSHCACHE for 64-bit.

  Thanks to: Alexey Kardashevskiy, Alistair Popple, Allen Pais, Andrew
  Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Balbir Singh, Benjamin
  Herrenschmidt, Breno Leitao, Christophe Leroy, Christophe Lombard,
  Cyril Bur, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven,
  Guilherme G. Piccoli, Gustavo Romero, Haren Myneni, Joel Stanley,
  Kamalesh Babulal, Kautuk Consul, Markus Elfring, Masami Hiramatsu,
  Michael Bringmann, Michael Neuling, Michal Suchanek, Naveen N. Rao,
  Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pedro Miraglia
  Franco de Carvalho, Philippe Bergheaud, Sandipan Das, Seth Forshee,
  Shriya, Stephen Rothwell, Stewart Smith, Sukadev Bhattiprolu, Tyrel
  Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, and William A.
  Kennington III"

* tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (151 commits)
  powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature
  powerpc/64s: Fix masking of SRR1 bits on instruction fault
  powerpc/64s: mm_context.addr_limit is only used on hash
  powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation
  powerpc/64s/hash: Allow MAP_FIXED allocations to cross 128TB boundary
  powerpc/64s/hash: Fix fork() with 512TB process address space
  powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case allocation
  powerpc/64s/hash: Fix 512T hint detection to use >= 128T
  powerpc: Fix DABR match on hash based systems
  powerpc/signal: Properly handle return value from uprobe_deny_signal()
  powerpc/fadump: use kstrtoint to handle sysfs store
  powerpc/lib: Implement UACCESS_FLUSHCACHE API
  powerpc/lib: Implement PMEM API
  powerpc/powernv/npu: Don't explicitly flush nmmu tlb
  powerpc/powernv/npu: Use flush_all_mm() instead of flush_tlb_mm()
  powerpc/powernv/idle: Round up latency and residency values
  powerpc/kprobes: refactor kprobe_lookup_name for safer string operations
  powerpc/kprobes: Blacklist emulate_update_regs() from kprobes
  powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftrace
  powerpc/kprobes: Disable preemption before invoking probe handler for optprobes
  ...
2017-11-16 12:47:46 -08:00
Mel Gorman
2d4894b5d2 mm: remove cold parameter from free_hot_cold_page*
Most callers users of free_hot_cold_page claim the pages being released
are cache hot.  The exception is the page reclaim paths where it is
likely that enough pages will be freed in the near future that the
per-cpu lists are going to be recycled and the cache hotness information
is lost.  As no one really cares about the hotness of pages being
released to the allocator, just ditch the parameter.

The APIs are renamed to indicate that it's no longer about hot/cold
pages.  It should also be less confusing as there are subtle differences
between them.  __free_pages drops a reference and frees a page when the
refcount reaches zero.  free_hot_cold_page handled pages whose refcount
was already zero which is non-obvious from the name.  free_unref_page
should be more obvious.

No performance impact is expected as the overhead is marginal.  The
parameter is removed simply because it is a bit stupid to have a useless
parameter copied everywhere.

[mgorman@techsingularity.net: add pages to head, not tail]
  Link: http://lkml.kernel.org/r/20171019154321.qtpzaeftoyyw4iey@techsingularity.net
Link: http://lkml.kernel.org/r/20171018075952.10627-8-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:06 -08:00
Kirill A. Shutemov
b4e98d9ac7 mm: account pud page tables
On a machine with 5-level paging support a process can allocate
significant amount of memory and stay unnoticed by oom-killer and memory
cgroup.  The trick is to allocate a lot of PUD page tables.  We don't
account PUD page tables, only PMD and PTE.

We already addressed the same issue for PMD page tables, see commit
dc6c9a35b6 ("mm: account pmd page tables to the process").
Introduction of 5-level paging brings the same issue for PUD page
tables.

The patch expands accounting to PUD level.

[kirill.shutemov@linux.intel.com: s/pmd_t/pud_t/]
  Link: http://lkml.kernel.org/r/20171004074305.x35eh5u7ybbt5kar@black.fi.intel.com
[heiko.carstens@de.ibm.com: s390/mm: fix pud table accounting]
  Link: http://lkml.kernel.org/r/20171103090551.18231-1-heiko.carstens@de.ibm.com
Link: http://lkml.kernel.org/r/20171002080427.3320-1-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Linus Torvalds
2bcc673101 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "Yet another big pile of changes:

   - More year 2038 work from Arnd slowly reaching the point where we
     need to think about the syscalls themself.

   - A new timer function which allows to conditionally (re)arm a timer
     only when it's either not running or the new expiry time is sooner
     than the armed expiry time. This allows to use a single timer for
     multiple timeout requirements w/o caring about the first expiry
     time at the call site.

   - A new NMI safe accessor to clock real time for the printk timestamp
     work. Can be used by tracing, perf as well if required.

   - A large number of timer setup conversions from Kees which got
     collected here because either maintainers requested so or they
     simply got ignored. As Kees pointed out already there are a few
     trivial merge conflicts and some redundant commits which was
     unavoidable due to the size of this conversion effort.

   - Avoid a redundant iteration in the timer wheel softirq processing.

   - Provide a mechanism to treat RTC implementations depending on their
     hardware properties, i.e. don't inflict the write at the 0.5
     seconds boundary which originates from the PC CMOS RTC to all RTCs.
     No functional change as drivers need to be updated separately.

   - The usual small updates to core code clocksource drivers. Nothing
     really exciting"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (111 commits)
  timers: Add a function to start/reduce a timer
  pstore: Use ktime_get_real_fast_ns() instead of __getnstimeofday()
  timer: Prepare to change all DEFINE_TIMER() callbacks
  netfilter: ipvs: Convert timers to use timer_setup()
  scsi: qla2xxx: Convert timers to use timer_setup()
  block/aoe: discover_timer: Convert timers to use timer_setup()
  ide: Convert timers to use timer_setup()
  drbd: Convert timers to use timer_setup()
  mailbox: Convert timers to use timer_setup()
  crypto: Convert timers to use timer_setup()
  drivers/pcmcia: omap1: Fix error in automated timer conversion
  ARM: footbridge: Fix typo in timer conversion
  drivers/sgi-xp: Convert timers to use timer_setup()
  drivers/pcmcia: Convert timers to use timer_setup()
  drivers/memstick: Convert timers to use timer_setup()
  drivers/macintosh: Convert timers to use timer_setup()
  hwrng/xgene-rng: Convert timers to use timer_setup()
  auxdisplay: Convert timers to use timer_setup()
  sparc/led: Convert timers to use timer_setup()
  mips: ip22/32: Convert timers to use timer_setup()
  ...
2017-11-13 17:56:58 -08:00
Nicholas Piggin
4722476bce powerpc/64s: mm_context.addr_limit is only used on hash
Radix keeps no meaningful state in addr_limit, so remove it from radix
code and rename to slb_addr_limit to make it clear it applies to hash
only.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13 23:35:43 +11:00
Nicholas Piggin
85e3f1adcb powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation
Radix VA space allocations test addresses against mm->task_size which
is 512TB, even in cases where the intention is to limit allocation to
below 128TB.

This results in mmap with a hint address below 128TB but address +
length above 128TB succeeding when it should fail (as hash does after
the previous patch).

Set the high address limit to be considered up front, and base
subsequent allocation checks on that consistently.

Fixes: f4ea6dcb08 ("powerpc/mm: Enable mappings above 128TB")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13 23:35:29 +11:00
Nicholas Piggin
35602f82d0 powerpc/64s/hash: Allow MAP_FIXED allocations to cross 128TB boundary
While mapping hints with a length that cross 128TB are disallowed,
MAP_FIXED allocations that cross 128TB are allowed. These are failing
on hash (on radix they succeed). Add an additional case for fixed
mappings to expand the addr_limit when crossing 128TB.

Fixes: f4ea6dcb08 ("powerpc/mm: Enable mappings above 128TB")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13 23:35:06 +11:00
Nicholas Piggin
effc1b2508 powerpc/64s/hash: Fix fork() with 512TB process address space
Hash unconditionally resets the addr_limit to default (128TB) when the
mm context is initialised. If a process has > 128TB mappings when it
forks, the child will not get the 512TB addr_limit, so accesses to
valid > 128TB mappings will fail in the child.

Fix this by only resetting the addr_limit to default if it was 0. Non
zero indicates it was duplicated from the parent (0 means exec()).

Fixes: f4ea6dcb08 ("powerpc/mm: Enable mappings above 128TB")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13 23:34:47 +11:00
Nicholas Piggin
6a72dc038b powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case allocation
When allocating VA space with a hint that crosses 128TB, the SLB
addr_limit variable is not expanded if addr is not > 128TB, but the
slice allocation looks at task_size, which is 512TB. This results in
slice_check_fit() incorrectly succeeding because the slice_count
truncates off bit 128 of the requested mask, so the comparison to the
available mask succeeds.

Fix this by using mm->context.addr_limit instead of mm->task_size for
testing allocation limits. This causes such allocations to fail.

Fixes: f4ea6dcb08 ("powerpc/mm: Enable mappings above 128TB")
Cc: stable@vger.kernel.org # v4.12+
Reported-by: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13 23:34:19 +11:00
Michael Ellerman
7ece370996 powerpc/64s/hash: Fix 512T hint detection to use >= 128T
Currently userspace is able to request mmap() search between 128T-512T
by specifying a hint address that is greater than 128T. But that means
a hint of 128T exactly will return an address below 128T, which is
confusing and wrong.

So fix the logic to check the hint is greater than *or equal* to 128T.

Fixes: f4ea6dcb08 ("powerpc/mm: Enable mappings above 128TB")
Cc: stable@vger.kernel.org # v4.12+
Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Suggested-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of Nick's bigger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13 23:34:06 +11:00
Balbir Singh
f79ad50ea3 powerpc/mm/radix: Fix crashes on Power9 DD1 with radix MMU and STRICT_RWX
When using the radix MMU on Power9 DD1, to work around a hardware
problem, radix__pte_update() is required to do a two stage update of
the PTE. First we write a zero value into the PTE, then we flush the
TLB, and then we write the new PTE value.

In the normal case that works OK, but it does not work if we're
updating the PTE that maps the code we're executing, because the
mapping is removed by the TLB flush and we can no longer execute from
it. Unfortunately the STRICT_RWX code needs to do exactly that.

The exact symptoms when we hit this case vary, sometimes we print an
oops and then get stuck after that, but I've also seen a machine just
get stuck continually page faulting with no oops printed. The variance
is presumably due to the exact layout of the text and the page size
used for the mappings. In all cases we are unable to boot to a shell.

There are possible solutions such as creating a second mapping of the
TLB flush code, executing from that, and then jumping back to the
original. However we don't want to add that level of complexity for a
DD1 work around.

So just detect that we're running on Power9 DD1 and refrain from
changing the permissions, effectively disabling STRICT_RWX on Power9
DD1.

Fixes: 7614ff3272 ("powerpc/mm/radix: Implement STRICT_RWX/mark_rodata_ro() for Radix")
Cc: stable@vger.kernel.org # v4.13+
Reported-by: Andrew Jeffery <andrew@aj.id.au>
[Changelog as suggested by Michael Ellerman <mpe@ellerman.id.au>]
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12 23:25:48 +11:00
Nicholas Piggin
0b2f5a8a79 powerpc/64s/radix: Improve TLB flushing for page table freeing
Unmaps that free page tables always flush the entire PID, which is
sub-optimal. Provide TLB range flushing with an additional PWC flush
that can be use for va range invalidations with PWC flush.

     Time to munmap N pages of memory including last level page table
     teardown (after mmap, touch), local invalidate:
     N           1       2      4      8     16     32     64
     vanilla  3.2us  3.3us  3.4us  3.6us  4.1us  5.2us  7.2us
     patched  1.4us  1.5us  1.7us  1.9us  2.6us  3.7us  6.2us

     Global invalidate:
     N           1       2      4      8     16      32     64
     vanilla  2.2us  2.3us  2.4us  2.6us  3.2us   4.1us  6.2us
     patched  2.1us  2.5us  3.4us  5.2us  8.7us  15.7us  6.2us

Local invalidates get much better across the board. Global ones have
the same issue where multiple tlbies for va flush do get slower than
the single tlbie to invalidate the PID. None of this test captures
the TLB benefits of avoiding killing everything.

Global gets worse, but it is brought in to line with global invalidate
for munmap()s that do not free page tables.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10 21:33:35 +11:00
Nicholas Piggin
f6f27951fd powerpc/64s/radix: Introduce local single page ceiling for TLB range flush
The single page flush ceiling is the cut-off point at which we switch
from invalidating individual pages, to invalidating the entire process
address space in response to a range flush.

Introduce a local variant of this heuristic because local and global
tlbie have significantly different properties:
- Local tlbiel requires 128 instructions to invalidate a PID, global
  tlbie only 1 instruction.
- Global tlbie instructions are expensive broadcast operations.

The local ceiling has been made much higher, 2x the number of
instructions required to invalidate the entire PID (i.e., 256 pages).

     Time to mprotect N pages of memory (after mmap, touch), local invalidate:
     N           32     34      64     128     256     512
     vanilla  7.4us  9.0us  14.6us  26.4us  50.2us  98.3us
     patched  7.4us  7.8us  13.8us  26.4us  51.9us  98.3us

The behaviour of both is identical at N=32 and N=512. Between there,
the vanilla kernel does a PID invalidate and the patched kernel does
a va range invalidate.

At N=128, these require the same number of tlbiel instructions, so
the patched version can be sen to be cheaper when < 128, and more
expensive when > 128. However this does not well capture the cost
of invalidated TLB.

The additional cost at 256 pages does not seem prohibitive. It may
be the case that increasing the limit further would continue to be
beneficial to avoid invalidating all of the process's TLB entries.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10 21:33:35 +11:00
Nicholas Piggin
cbf09c8377 powerpc/64s/radix: Optimize flush_tlb_range
Currently for radix, flush_tlb_range flushes the entire PID, because
the Linux mm code does not tell us about page size here for THP vs
regular pages. This is quite sub-optimal for small mremap / mprotect
/ change_protection.

So implement va range flushes with two flush passes, one for each
page size (regular and THP). The second flush has an order of matnitude
fewer tlbie instructions than the first, so it is a relatively small
additional cost.

There is still room for improvement here with some changes to generic
APIs, particularly if there are mostly THP pages to be invalidated,
the small page flushes could be reduced.

Time to mprotect 1 page of memory (after mmap, touch):
vanilla 2.9us   1.8us
patched 1.2us   1.6us

Time to mprotect 30 pages of memory (after mmap, touch):
vanilla 8.2us   7.2us
patched 6.9us   17.9us

Time to mprotect 34 pages of memory (after mmap, touch):
vanilla 9.1us   8.0us
patched 9.0us   8.0us

34 pages is the point at which the invalidation switches from va
to entire PID, which tlbie can do in a single instruction. This is
why in the case of 30 pages, the new code runs slower for this test.
This is a deliberate tradeoff already present in the unmap and THP
promotion code, the idea is that the benefit from avoiding flushing
entire TLB for this PID on all threads in the system.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10 21:33:33 +11:00
Nicholas Piggin
d665767e39 powerpc/64s/radix: Implement _tlbie(l)_va_range flush functions
Move the barriers and range iteration down into the _tlbie* level,
which improves readability.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10 21:32:09 +11:00
Nicholas Piggin
14001c6093 powerpc/64s/radix: Optimize TLB range flush barriers
Short range flushes issue a sequences of tlbie(l) instructions for
individual effective addresses. These do not all require individual
barrier sequences, only one covering all tlbie(l) instructions.

Commit f7327e0ba3 ("powerpc/mm/radix: Remove unnecessary ptesync")
made a similar optimization for tlbiel for PID flushing.

For tlbie, the ISA says:

    The tlbsync instruction provides an ordering function for the
    effects of all tlbie instructions executed by the thread executing
    the tlbsync instruction, with respect to the memory barrier
    created by a subsequent ptesync instruction executed by the same
    thread.

Time to munmap 30 pages of memory (after mmap, touch):
         local   global
vanilla  10.9us  22.3us
patched   3.4us  14.4us

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10 21:30:44 +11:00
Michael Ellerman
a54c61f46e Merge branch 'fixes' into next
We have some dependencies & conflicts between patches in fixes and
things to go in next, both in the radix TLB flush code and the IMC PMU
driver. So merge fixes into next.
2017-11-10 20:55:03 +11:00
Michal Suchanek
bf751e30b4 powerpc/mm/hash: Remove stale comment.
In commit e6f81a9201 ("powerpc/mm/hash: Support 68 bit VA") the
masking is folded into ASM_VSID_SCRAMBLE but the comment about masking
is removed only from the firt use of ASM_VSID_SCRAMBLE.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-07 23:28:26 +11:00
Michael Ellerman
1fd6c02207 powerpc/mm: Add a CONFIG option to choose if radix is used by default
Currently if the hardware supports the radix MMU we will use
it, *unless* "disable_radix" is passed on the kernel command line.

However some users would like the reverse semantics. ie. The kernel
uses the hash MMU by default, unless radix is explicitly requested on
the command line.

So add a CONFIG option to choose whether we use radix by default or
not, and expand the disable_radix command line option to allow
"disable_radix=no" which *enables* radix.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 16:48:15 +11:00
Michael Ellerman
4e00374704 powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64
CONFIG_PPC_STD_MMU_64 indicates support for the "standard" powerpc MMU
on 64-bit CPUs. The "standard" MMU refers to the hash page table MMU
found in "server" processors, from IBM mainly.

Currently CONFIG_PPC_STD_MMU_64 is == CONFIG_PPC_BOOK3S_64. While it's
annoying to have two symbols that always have the same value, it's not
quite annoying enough to bother removing one.

However with the arrival of Power9, we now have the situation where
CONFIG_PPC_STD_MMU_64 is enabled, but the kernel is running using the
Radix MMU - *not* the "standard" MMU. So it is now actively confusing
to use it, because it implies that code is disabled or inactive when
the Radix MMU is in use, however that is not necessarily true.

So s/CONFIG_PPC_STD_MMU_64/CONFIG_PPC_BOOK3S_64/, and do some minor
formatting updates of some of the affected lines.

This will be a pain for backports, but c'est la vie.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 16:48:14 +11:00
Aneesh Kumar K.V
7f142661d4 powerpc/mm/hash: Add pr_fmt() to hash_utils64.c
Make the printks look a bit nicer by adding a prefix.

Radix config now do
 radix-mmu: Page sizes from device-tree:
 radix-mmu: Page size shift = 12 AP=0x0
 radix-mmu: Page size shift = 16 AP=0x5
 radix-mmu: Page size shift = 21 AP=0x1
 radix-mmu: Page size shift = 30 AP=0x2

This patch update hash config to do similar dmesg output. With the patch we have

 hash-mmu: Page sizes from device-tree:
 hash-mmu: base_shift=12: shift=12, sllp=0x0000, avpnm=0x00000000, tlbiel=1, penc=0
 hash-mmu: base_shift=12: shift=16, sllp=0x0000, avpnm=0x00000000, tlbiel=1, penc=7
 hash-mmu: base_shift=12: shift=24, sllp=0x0000, avpnm=0x00000000, tlbiel=1, penc=56
 hash-mmu: base_shift=16: shift=16, sllp=0x0110, avpnm=0x00000000, tlbiel=1, penc=1
 hash-mmu: base_shift=16: shift=24, sllp=0x0110, avpnm=0x00000000, tlbiel=1, penc=8
 hash-mmu: base_shift=20: shift=20, sllp=0x0111, avpnm=0x00000000, tlbiel=0, penc=2
 hash-mmu: base_shift=24: shift=24, sllp=0x0100, avpnm=0x00000001, tlbiel=0, penc=0
 hash-mmu: base_shift=34: shift=34, sllp=0x0120, avpnm=0x000007ff, tlbiel=0, penc=3

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 16:48:13 +11:00
Nicholas Piggin
30b49ec798 powerpc/64s/radix: Fix process table entry cache invalidation
According to the architecture, the process table entry cache must be
flushed with tlbie RIC=2.

Currently the process table entry is set to invalid right before the
PID is returned to the allocator, with no invalidation. This works on
existing implementations that are known to not cache the process table
entry for any except the current PIDR.

It is architecturally correct and cleaner to invalidate with RIC=2
after clearing the process table entry and before the PID is returned
to the allocator. This can be done in arch_exit_mmap that runs before
the final flush, and to ensure the final flush (fullmm) is always a
RIC=2 variant.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 16:48:10 +11:00
Nicholas Piggin
dffe8449c5 powerpc/64s/radix: Improve preempt handling in TLB code
Preempt should be consistently disabled for mm_is_thread_local tests,
so bring the rest of these under preempt_disable().

Preempt does not need to be disabled for the mm->context.id tests,
which allows simplification and removal of gotos.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 16:48:10 +11:00
Linus Torvalds
866ba84ea3 powerpc fixes for 4.14 #6
A fix to the handling of misaligned paste instructions (P9 only), where a change
 to a #define has caused the check for the instruction to always fail.
 
 The preempt handling was unbalanced in the radix THP flush (P9 only). Though we
 don't generally use preempt we want to keep it working as much as possible.
 
 Two fixes for IMC (P9 only), one when booting with restricted number of CPUs and
 one in the error handling when initialisation fails due to firmware etc.
 
 A revert to fix function_graph on big endian machines, and then a rework of the
 reverted patch to fix kprobes blacklist handling on big endian machines.
 
 Thanks to:
   Anju T Sudhakar, Guilherme G. Piccoli, Madhavan Srinivasan, Naveen N. Rao,
   Nicholas Piggin, Paul Mackerras.
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Merge tag 'powerpc-4.14-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Some more powerpc fixes for 4.14.

  This is bigger than I like to send at rc7, but that's at least partly
  because I didn't send any fixes last week. If it wasn't for the IMC
  driver, which is new and getting heavy testing, the diffstat would
  look a bit better. I've also added ftrace on big endian to my test
  suite, so we shouldn't break that again in future.

   - A fix to the handling of misaligned paste instructions (P9 only),
     where a change to a #define has caused the check for the
     instruction to always fail.

   - The preempt handling was unbalanced in the radix THP flush (P9
     only). Though we don't generally use preempt we want to keep it
     working as much as possible.

   - Two fixes for IMC (P9 only), one when booting with restricted
     number of CPUs and one in the error handling when initialisation
     fails due to firmware etc.

   - A revert to fix function_graph on big endian machines, and then a
     rework of the reverted patch to fix kprobes blacklist handling on
     big endian machines.

  Thanks to: Anju T Sudhakar, Guilherme G. Piccoli, Madhavan Srinivasan,
  Naveen N. Rao, Nicholas Piggin, Paul Mackerras"

* tag 'powerpc-4.14-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/perf: Fix core-imc hotplug callback failure during imc initialization
  powerpc/kprobes: Dereference function pointers only if the address does not belong to kernel text
  Revert "powerpc64/elfv1: Only dereference function descriptor for non-text symbols"
  powerpc/64s/radix: Fix preempt imbalance in TLB flush
  powerpc: Fix check for copy/paste instructions in alignment handler
  powerpc/perf: Fix IMC allocation routine
2017-11-03 09:25:53 -07:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Nicholas Piggin
26e53d5ebe powerpc/64s/radix: Fix preempt imbalance in TLB flush
Fixes: 424de9c6e3 ("powerpc/mm/radix: Avoid flushing the PWC on every flush_tlb_range")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-25 18:00:00 +02:00
Michael Ellerman
6773027205 powerpc/mm/radix: Drop unneeded NULL check
We call these functions with non-NULL mm or vma. Hence we can skip the
NULL check in these functions. We also remove now unused function
__local_flush_hugetlb_page().

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Drop the checks with is_vm_hugetlb_page() as noticed by Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-22 12:08:31 +02:00
Michael Bringmann
8bc931495d powerpc/vphn: Fix numa update end-loop bug
powerpc/vphn: On Power systems with shared configurations of CPUs
and memory, there are some issues with the association of additional
CPUs and memory to nodes when hot-adding resources.  This patch
fixes an end-of-updates processing problem observed occasionally
in numa_update_cpu_topology().

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-16 23:12:05 +11:00
Michael Bringmann
cee5405da4 powerpc/hotplug: Improve responsiveness of hotplug change
powerpc/hotplug: On Power systems with shared configurations of CPUs
and memory, there are some issues with the association of additional
CPUs and memory to nodes when hot-adding resources.  During hotplug
CPU operations, this patch resets the timer on topology update work
function to a small value to better ensure that the CPU topology is
detected and configured sooner.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-16 23:12:04 +11:00
Michael Bringmann
a3496e9137 powerpc/vphn: Improve recognition of PRRN/VPHN
powerpc/vphn: On Power systems with shared configurations of CPUs
and memory, there are some issues with the association of additional
CPUs and memory to nodes when hot-adding resources.  This patch
updates the initialization checks to independently recognize PRRN
or VPHN support.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-16 23:12:03 +11:00
Michael Bringmann
17f444c054 powerpc/vphn: Update CPU topology when VPHN enabled
powerpc/vphn: On Power systems with shared configurations of CPUs
and memory, there are some issues with the association of additional
CPUs and memory to nodes when hot-adding resources.  This patch
corrects the currently broken capability to set the topology for
shared CPUs in LPARs.  At boot time for shared CPU lpars, the
topology for each CPU was being set to node zero.  Now when
numa_update_cpu_topology() is called appropriately, the Virtual
Processor Home Node (VPHN) capabilities information provided by the
pHyp allows the appropriate node in the shared configuration to be
selected for the CPU.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-16 23:12:03 +11:00
Thiago Jung Bauermann
6b2c08f989 powerpc: Don't call lockdep_assert_cpus_held() from arch_update_cpu_topology()
It turns out that not all paths calling arch_update_cpu_topology() hold
cpu_hotplug_lock, but that's OK because those paths can't race with
any concurrent hotplug events.

Warnings were reported with the following trace:

  lockdep_assert_cpus_held
  arch_update_cpu_topology
  sched_init_domains
  sched_init_smp
  kernel_init_freeable
  kernel_init
  ret_from_kernel_thread

Which is safe because it's called early in boot when hotplug is not
live yet.

And also this trace:

  lockdep_assert_cpus_held
  arch_update_cpu_topology
  partition_sched_domains
  cpuset_update_active_cpus
  sched_cpu_deactivate
  cpuhp_invoke_callback
  cpuhp_down_callbacks
  cpuhp_thread_fun
  smpboot_thread_fn
  kthread
  ret_from_kernel_thread

Which is safe because it's called as part of CPU hotplug, so although
we don't hold the CPU hotplug lock, there is another thread driving
the CPU hotplug operation which does hold the lock, and there is no
race.

Thanks to tglx for deciphering it for us.

Fixes: 3e401f7a2e ("powerpc: Only obtain cpu_hotplug_lock if called by rtasd")
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-10 21:02:04 +11:00
Kees Cook
df7e828c1b timer: Remove init_timer_deferrable() in favor of timer_setup()
This refactors the only users of init_timer_deferrable() to use
the new timer_setup() and from_timer(). Removes definition of
init_timer_deferrable().

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David S. Miller <davem@davemloft.net> # for networking parts
Acked-by: Sebastian Reichel <sre@kernel.org> # for drivers/hsi parts
Cc: linux-mips@linux-mips.org
Cc: Petr Mladek <pmladek@suse.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kalle Valo <kvalo@qca.qualcomm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: linux1394-devel@lists.sourceforge.net
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: linux-s390@vger.kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ursula Braun <ubraun@linux.vnet.ibm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Harish Patil <harish.patil@cavium.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Manish Chopra <manish.chopra@cavium.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-pm@vger.kernel.org
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Mark Gross <mark.gross@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: linux-watchdog@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-wireless@vger.kernel.org
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Michael Reed <mdr@sgi.com>
Cc: netdev@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Link: https://lkml.kernel.org/r/1507159627-127660-6-git-send-email-keescook@chromium.org
2017-10-05 15:01:18 +02:00
Guenter Roeck
7c6a4f3b16 powerpc/mm: Call flush_tlb_kernel_range with interrupts enabled
flush_tlb_kernel_range() may call smp_call_function_many() which expects
interrupts to be enabled. This results in a traceback.

WARNING: CPU: 0 PID: 1 at kernel/smp.c:416 smp_call_function_many+0xcc/0x2fc
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.14.0-rc1-00009-g0666f56 #1
task: cf830000 task.stack: cf82e000
NIP:  c00a93c8 LR: c00a9634 CTR: 00000001
REGS: cf82fde0 TRAP: 0700   Not tainted  (4.14.0-rc1-00009-g0666f56)
MSR:  00021000 <CE,ME>  CR: 24000082  XER: 00000000

GPR00: c00a9634 cf82fe90 cf830000 c050ad3c c0015a54 00000000 00000001 00000001
GPR08: 00000001 00000000 00000000 cf82e000 24000084 00000000 c0003150 00000000
GPR16: 00000000 00000000 00000000 00000000 00000000 00000001 00000000 c0510000
GPR24: 00000000 c0015a54 00000000 c050ad3c c051823c c050ad3c 00000025 00000000
NIP [c00a93c8] smp_call_function_many+0xcc/0x2fc
LR [c00a9634] smp_call_function+0x3c/0x50
Call Trace:
[cf82fe90] [00000010] 0x10 (unreliable)
[cf82fed0] [c00a9634] smp_call_function+0x3c/0x50
[cf82fee0] [c0015d2c] flush_tlb_kernel_range+0x20/0x38
[cf82fef0] [c001524c] mark_initmem_nx+0x154/0x16c
[cf82ff20] [c001484c] free_initmem+0x20/0x4c
[cf82ff30] [c000316c] kernel_init+0x1c/0x108
[cf82ff40] [c000f3a8] ret_from_kernel_thread+0x5c/0x64
Instruction dump:
7c0803a6 7d808120 38210040 4e800020 3d20c052 812981a0 2f890000 40beffac
3d20c051 8929ac64 2f890000 40beff9c <0fe00000> 4bffff94 7fc3f378 7f64db78

Fixes: 3184cc4b6f ("powerpc/mm: Fix kernel RAM protection after freeing ...")
Fixes: e611939fc8 ("powerpc/mm: Ensure change_page_attr() doesn't ...")
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-04 22:15:30 +11:00
Frederic Barrat
03b8abedf4 cxl: Enable global TLBIs for cxl contexts
The PSL and nMMU need to see all TLB invalidations for the memory
contexts used on the adapter. For the hash memory model, it is done by
making all TLBIs global as soon as the cxl driver is in use. For
radix, we need something similar, but we can refine and only convert
to global the invalidations for contexts actually used by the device.

The new mm_context_add_copro() API increments the 'active_cpus' count
for the contexts attached to the cxl adapter. As soon as there's more
than 1 active cpu, the TLBIs for the context become global. Active cpu
count must be decremented when detaching to restore locality if
possible and to avoid overflowing the counter.

The hash memory model support is somewhat limited, as we can't
decrement the active cpus count when mm_context_remove_copro() is
called, because we can't flush the TLB for a mm on hash. So TLBIs
remain global on hash.

Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Fixes: f24be42aab ("cxl: Add psl9 specific code")
Tested-by: Alistair Popple <alistair@popple.id.au>
[mpe: Fold in updated comment on the barrier from Fred]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-28 17:09:16 +10:00
Frederic Barrat
6110236b9b powerpc/mm: Export flush_all_mm()
With the optimizations introduced by commit a46cc7a90f
("powerpc/mm/radix: Improve TLB/PWC flushes"), flush_tlb_mm() no
longer flushes the page walk cache (PWC) with radix. This patch
introduces flush_all_mm(), which flushes everything, TLB and PWC, for
a given mm.

Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-By: Alistair Popple <alistair@popple.id.au>
[mpe: Add a WARN_ON_ONCE() in the empty hash routines]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-28 16:28:22 +10:00
Markus Elfring
aae85e3c20 powerpc/mm: Use seq_putc() in two functions
Two single characters (line breaks) should be put into a sequence.
Thus use the corresponding function "seq_putc".

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-01 16:42:52 +10:00
Christophe Leroy
c0622167e3 powerpc: fix location of two EXPORT_SYMBOL
Commit 9445aa1a30 ("ppc: move exports to definitions")
added EXPORT_SYMBOL() for memset() and flush_hash_pages() in
the middle of the functions.

This patch moves them at the end of the two functions.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-01 16:42:45 +10:00
Michael Ellerman
6deb6b474b powerpc/mm/radix: Prettify mapped memory range print out
When we map memory at boot we print out the ranges of real addresses
that we mapped and the page size that was used.

Currently it's a bit ugly:

  Mapped range 0x0 - 0x2000000000 with 0x40000000
  Mapped range 0x200000000000 - 0x202000000000 with 0x40000000

Pad the addresses so they line up, and print the page size using
actual units, eg:

  Mapped 0x0000000000000000-0x0000000001200000 with 64.0 KiB pages
  Mapped 0x0000000001200000-0x0000000040000000 with 2.00 MiB pages
  Mapped 0x0000000040000000-0x0000000100000000 with 1.00 GiB pages

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:42 +10:00
Michael Ellerman
bd350f7121 powerpc/mm/radix: Add pr_fmt() to pgtable-radix.c
Make the printks look a bit nicer by adding a prefix.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:41 +10:00
Benjamin Herrenschmidt
3a2df3798d powerpc/mm: Make switch_mm_irqs_off() out of line
It's too big to be inline, there is no reason to keep it
that way.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Rework to incorporate the comment changes via fixes branch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-23 22:48:51 +10:00
Benjamin Herrenschmidt
a619e59c07 powerpc/mm: Optimize detection of thread local mm's
Instead of comparing the whole CPU mask every time, let's
keep a counter of how many bits are set in the mask. Thus
testing for a local mm only requires testing if that counter
is 1 and the current CPU bit is set in the mask.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-23 22:28:38 +10:00
Benjamin Herrenschmidt
b426e4bd77 powerpc/mm: Use mm_is_thread_local() instread of open-coding
We open-code testing for the mm being local to the current CPU
in a few places. Use our existing helper instead.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-23 22:27:45 +10:00
Michael Ellerman
15c659ff9d Merge branch 'fixes' into next
There's a non-trivial dependency between some commits we want to put in
next and the KVM prefetch work around that went into fixes. So merge
fixes into next.
2017-08-23 22:20:10 +10:00
Aneesh Kumar K.V
0f4bc0932e powerpc/mm/cxl: Add the fault handling cpu to mm cpumask
We use mm cpumask for serializing against lockless page table walk.
Anybody who is doing a lockless page table walk is expected to disable
irq and only cpus in mm cpumask is expected do the lockless walk. This
ensure that a THP split can send IPI to only cpus in the mm cpumask,
to make sure there are no parallel lockless page table walk.

Add the CAPI fault handling cpu to the mm cpumask so that we can do
the lockless page table walk while inserting hash page table entries.

Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-17 23:31:52 +10:00
Aneesh Kumar K.V
fa4531f753 powerpc/mm: Don't send IPI to all cpus on THP updates
Now that we made sure that lockless walk of linux page table is mostly
limitted to current task(current->mm->pgdir) we can update the THP
update sequence to only send IPI to CPUs on which this task has run.
This helps in reducing the IPI overload on systems with large number
of CPUs.

WRT kvm even though kvm is walking page table with vpc->arch.pgdir,
it is done only on secondary CPUs and in that case we have primary CPU
added to task's mm cpumask. Sending an IPI to primary will force the
secondary to do a vm exit and hence this mm cpumask usage is safe
here.

WRT CAPI, we still end up walking linux page table with capi context
MM. For now the pte lookup serialization sends an IPI to all CPUs in
CPI is in use. We can further improve this by adding the CAPI
interrupt handling CPU to task mm cpumask. That will be done in a
later patch.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-17 23:31:13 +10:00
Michael Ellerman
8434f0892e Merge branch 'topic/ppc-kvm' into next
Bring in the commit to rename find_linux_pte_or_hugepte() which touches
arch and KVM code, and might need to be merged with the kvmppc tree to
avoid conflicts.
2017-08-17 23:14:17 +10:00
Aneesh Kumar K.V
94171b19c3 powerpc/mm: Rename find_linux_pte_or_hugepte()
Add newer helpers to make the function usage simpler. It is always
recommended to use find_current_mm_pte() for walking the page table.
If we cannot use find_current_mm_pte(), it should be documented why
the said usage of __find_linux_pte() is safe against a parallel THP
split.

For now we have KVM code using __find_linux_pte(). This is because kvm
code ends up calling __find_linux_pte() in real mode with MSR_EE=0 but
with PACA soft_enabled = 1. We may want to fix that later and make
sure we keep the MSR_EE and PACA soft_enabled in sync. When we do that
we can switch kvm to use find_linux_pte().

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-17 23:13:46 +10:00
Aneesh Kumar K.V
79cc38ded1 powerpc/mm/hugetlb: Add support for reserving gigantic huge pages via kernel command line
With commit aa888a7497 ("hugetlb: support larger than MAX_ORDER") we added
support for allocating gigantic hugepages via kernel command line. Switch
ppc64 arch specific code to use that.

W.r.t FSL support, we now limit our allocation range using BOOTMEM_ALLOC_ACCESSIBLE.

We use the kernel command line to do reservation of hugetlb pages on powernv
platforms. On pseries hash mmu mode the supported gigantic huge page size is
16GB and that can only be allocated with hypervisor assist. For pseries the
command line option doesn't do the allocation. Instead pseries does gigantic
hugepage allocation based on hypervisor hint that is specified via
"ibm,expected#pages" property of the memory node.

Cc: Scott Wood <oss@buserror.net>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 14:56:12 +10:00
Christophe Leroy
ca8afd4046 powerpc/hugetlb: fix page rights verification in gup_hugepte()
gup_hugepte() checks if pages are present and readable, and
when  'write' is set, also checks if the pages are writable.

Initially this was done by checking if _PAGE_PRESENT and
_PAGE_READ were set. In addition, _PAGE_WRITE was verified for write
accesses.

The problem is that we have to handle the three following cases:
1/ The target defines __PAGE_READ and __PAGE_WRITE
2/ The target defines __PAGE_RW
3/ The target defines __PAGE_RO

In case 1/, this is obvious
In case 2/, __PAGE_READ is defined as 0 and __PAGE_WRITE as __PAGE_RW
so it works as well.
But in case 3, __PAGE_RW is defined as 0, which means __PAGE_WRITE is 0
and then the test returns true (page writable) in all cases.

A first correction was attempted in commit 6b8cb66a6a ("powerpc: Fix
usage of _PAGE_RO in hugepage"), but that fix is wrong:
instead of checking that the page is writable when write is requested,
it checks that the page is NOT writable when write is NOT requested.

This patch adds a new pte_read() helper to check whether a page is
readable or not. This avoids handling all possible cases in
gup_hugepte().

Then gup_hugepte() is modified to use pte_present(), pte_read()
and pte_write() instead of the raw flags.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:58 +10:00
Christophe Leroy
4cfac2f9c7 powerpc/mm: Simplify __set_fixmap()
__set_fixmap() uses __fix_to_virt() then does the boundary checks
by it self. Instead, we can use fix_to_virt() which does the
verification at build time. For this, we need to use it inline
so that GCC can see the real value of idx at buildtime.

In the meantime, we remove the 'fixmaps' variable.
This variable is set but has never been used from the beginning
(commit 2c419bdeca ("[POWERPC] Port fixmap from x86 and use
for kmap_atomic"))

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:58 +10:00
Christophe Leroy
86b19520e7 powerpc/mm: declare some local functions static
get_pteptr() and __mapin_ram_chunk() are only used locally,
so define them static

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:57 +10:00
Christophe Leroy
95902e6c88 powerpc/mm: Implement STRICT_KERNEL_RWX on PPC32
This patch implements STRICT_KERNEL_RWX on PPC32.

As for CONFIG_DEBUG_PAGEALLOC, it deactivates BAT and LTLB mappings
in order to allow page protection setup at the level of each page.

As BAT/LTLB mappings are deactivated, there might be a performance
impact.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:57 +10:00
Christophe Leroy
3184cc4b6f powerpc/mm: Fix kernel RAM protection after freeing unused memory on PPC32
As seen below, allthough the init sections have been freed, the
associated memory area is still marked as executable in the
page tables.

~ dmesg
[    5.860093] Freeing unused kernel memory: 592K (c0570000 - c0604000)

~ cat /sys/kernel/debug/kernel_page_tables
---[ Start of kernel VM ]---
0xc0000000-0xc0497fff        4704K  rw  X  present dirty accessed shared
0xc0498000-0xc056ffff         864K  rw     present dirty accessed shared
0xc0570000-0xc059ffff         192K  rw  X  present dirty accessed shared
0xc05a0000-0xc7ffffff      125312K  rw     present dirty accessed shared
---[ vmalloc() Area ]---

This patch fixes that.

The implementation is done by reusing the change_page_attr()
function implemented for CONFIG_DEBUG_PAGEALLOC

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:56 +10:00
Christophe Leroy
e611939fc8 powerpc/mm: Ensure change_page_attr() doesn't invalidate pinned TLBs
__change_page_attr() uses flush_tlb_page().
flush_tlb_page() uses tlbie instruction, which also invalidates
pinned TLBs, which is not what we expect.

This patch modifies the implementation to use flush_tlb_kernel_range()
instead. This will make use of tlbia which will preserve pinned TLBs.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:56 +10:00
Christophe Leroy
346bcc4d33 powerpc/8xx: mark init functions with __init
setup_initial_memory_limit() is only called during init.
mmu_patch_cmp_limit() is only called from 8xx_mmu.c

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:54 +10:00
Christophe Leroy
a3059b0ca0 powerpc/8xx: Make pinning of ITLBs optional
As stated in a comment in head_8xx.S, today we "Always pin the first
8 MB ITLB to prevent ITLB misses while mucking around with SRR0/SRR1
in asm".

This issue has just been cleared by the preceding patch, therefore
we can make this pinning optional (on by default) and independent
of DATA pinning.

This patch also makes pinning of IMMR independent of pinning of DATA.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:53 +10:00
Christophe Leroy
eef784bbe7 powerpc/8xx: Ensures RAM mapped with LTLB is seen as block mapped on 8xx.
On the 8xx, the RAM mapped with LTLBs must be seen as block mapped,
just like areas mapped with BATs on standard PPC32.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:52 +10:00
Michael Ellerman
7559952e1f powerpc/mm: Fix section mismatch warning in early_check_vec5()
early_check_vec5() is called from and calls __init routines, so should
also be __init.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 23:40:51 +10:00
Christophe Leroy
4915349b10 powerpc/8xx: Use symbolic names for DSISR bits in DSI
Use symbolic names for DSISR bits in DSI

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 23:32:20 +10:00
Christophe Leroy
968159c003 powerpc/8xx: Getting rid of remaining use of CONFIG_8xx
Two config options exist to define powerpc MPC8xx:
* CONFIG_PPC_8xx
* CONFIG_8xx

arch/powerpc/platforms/Kconfig.cputype has contained the following
comment about CONFIG_8xx item for some years:
"# this is temp to handle compat with arch=ppc"

arch/powerpc is now the only place with remaining use of
CONFIG_8xx: get rid of them.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 23:32:12 +10:00
Suraj Jitindar Singh
7cd2a8695e powerpc/mm: Properly invalidate when setting process table base
The host process table base is stored in the partition table by calling
the function native_register_process_table(). Currently this just sets
the entry in memory and is missing a subsequent cache invalidation
instruction. Any update to the partition table should be followed by a
cache invalidation instruction specifying invalidation of the caching of
any partition table entries (RIC = 2, PRS = 0).

We already have a function to update the partition table with the
required cache invalidation instructions - mmu_partition_table_set_entry().
Update the native_register_process_table() function to call
mmu_partition_table_set_entry(), this ensures all appropriate
invalidation will be performed.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Use a local for patb0 to clean it up slightly]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 22:30:03 +10:00
Michael Ellerman
21a0e8c14b powerpc/mm/hash64: Make vmalloc 56T on hash
On 64-bit book3s, with the hash MMU, we currently define the kernel
virtual space (vmalloc, ioremap etc.), to be 16T in size. This is a
leftover from pre v3.7 when our user VM was also 16T.

Of that 16T we split it 50/50, with half used for PCI IO and ioremap
and the other 8T for vmalloc.

We never bothered to make it any bigger because 8T of vmalloc ought to
be enough for anybody. But it turns out that's not true, the per cpu
allocator wants large amounts of vmalloc space, not to make large
allocations, but to allow a large stride between allocations, because
we use pcpu_embed_first_chunk().

With a bit of juggling we can increase the entire kernel virtual space
to 64T. The only real complication is the check of the address in the
SLB miss handler, see the comment in the code.

Although we could continue to split virtual space 50/50 as we do now,
no one seems to be running out of PCI IO or ioremap space. So instead
keep that as 8T, and use the remaining 56T for vmalloc.

In future we should be able to increase the kernel virtual space to
512T, the code already supports that, it just needs testing on older
hardware.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2017-08-08 19:37:05 +10:00
Michael Ellerman
b5048de04b powerpc/mm/slb: Move comment next to the code it's referring to
There is a comment in slb_allocate() referring to the load of
paca->vmalloc_sllp, but it's several lines prior in the assembly.
We're about to change this code, and we want to add another comment,
so move the comment immediately prior to the instruction it's talking
about.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-08 19:37:04 +10:00
Michael Ellerman
63ee9b2ff9 powerpc/mm/book3s64: Make KERN_IO_START a variable
Currently KERN_IO_START is defined as:

 #define KERN_IO_START  (KERN_VIRT_START + (KERN_VIRT_SIZE >> 1))

Although it looks like a constant, both the components are actually
variables, to allow us to have a different value between Radix and
Hash with a single kernel.

However that still requires both Radix and Hash to place the kernel IO
region at the same location relative to the start and end of the
kernel virtual region (namely 1/2 way through it), and we'd like to
change that.

So split KERN_IO_START out into its own variable, and initialise it
for Radix and Hash. In the medium term we should be able to
reconsolidate this, by doing a more involved rearrangement of the
location of the regions.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-08 19:37:04 +10:00
Benjamin Herrenschmidt
6ff4d3e966 powerpc: Remove old unused icswx based coprocessor support
We have a whole pile of unused code to maintain the ACOP register,
allocate coprocessor PIDs and handle ACOP faults. This mechanism
was used for the HFI adapter on POWER7 which is dead and gone and
whose driver never went upstream. It was used on some A2 core based
stuff that also never saw the light of day.

Take out all that code.

There is still some POWER8 coprocessor code that uses icswx but it's
kernel only and thus doesn't use any of that infrastructure.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:52 +10:00
Benjamin Herrenschmidt
8f5ca0b319 powerpc/mm: Cleanup check for stack expansion
When hitting below a VM_GROWSDOWN vma (typically growing the stack),
we check whether it's a valid stack-growing instruction and we
check the distance to GPR1. This is largely open coded with lots
of comments, so move it out to a helper.

While at it, make store_update_sp a boolean.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:51 +10:00
Benjamin Herrenschmidt
f43bb27ebf powerpc/mm: Don't lose "major" fault indication on retry
If the first iteration returns VM_FAULT_MAJOR but the second
one doesn't, we fail to account the fault as a major fault.

This fixes it and brings the code in line with x86.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:51 +10:00
Benjamin Herrenschmidt
bd0d63f809 powerpc/mm: Move page fault VMA access checks to a helper
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:51 +10:00
Benjamin Herrenschmidt
d2e0d2c51a powerpc/mm: Set fault flags earlier
Move out the code that sets FAULT_FLAG_WRITE so the block that check
access permissions can be extracted. While at it also set
FAULT_FLAG_INSTRUCTION which will be used for protection keys.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:50 +10:00
Benjamin Herrenschmidt
b15021d994 powerpc/mm: Add a bunch of (un)likely annotations to do_page_fault
Mostly for the failure cases

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:50 +10:00
Benjamin Herrenschmidt
11ccdd33d6 powerpc/mm: Move/simplify faulthandler_disabled() and !mm check
Do the check before we re-enable interrupts and clean the code
up a bit.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:49 +10:00
Benjamin Herrenschmidt
2865d08dd9 powerpc/mm: Move the DSISR_PROTFAULT sanity check
This has a page of comment explaining what's going on right in
the middle of do_page_fault() which makes things a bit hard to
follow. Move it to a helper instead. Also do the test earlier
as there's no point waiting until after we found the VMA.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:49 +10:00
Benjamin Herrenschmidt
04aafdc601 powerpc/mm: Cosmetic fix to page fault accounting
No need to break those lines, they aren't that long

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:48 +10:00
Benjamin Herrenschmidt
3da026480a powerpc/mm: Move CMO accounting out of do_page_fault into a helper
It makes do_page_fault() more readable. No functional change.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:48 +10:00
Benjamin Herrenschmidt
b5c8f0fd59 powerpc/mm: Rework mm_fault_error()
First, handle the normal retry failure in do_page_fault itself,
since it's a simple return statement. That allows us to remove
the "continue" special return code from mm_fault_error().

Once that's done, we can have an implementation much closer to
x86 where we only call mm_fault_error() if VM_FAULT_ERROR is set
and directly return.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:47 +10:00
Benjamin Herrenschmidt
c3350602e8 powerpc/mm: Make bad_area* helper functions
Instead of goto labels, instead call those functions and return.

This gets us closer to x86 and allows us to shring do_page_fault()
even more.

The main difference with x86 is that those function return a value
which we then return from do_page_fault(). That value is our
return value from do_page_fault() which we use to generate
kernel faults.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:47 +10:00
Benjamin Herrenschmidt
d3ca587404 powerpc/mm: Fix reporting of kernel execute faults
We currently test for is_exec and DSISR_PROTFAULT but that doesn't
make sense as this is the wrong error bit to test for an execute
permission failure.

In fact, we had code that would return early if we had an exec
fault in kernel mode so I think that was just dead code anyway.

Finally the location of that test is awkward and prevents further
simplifications.

So instead move that test into a helper along with the existing
early test for kernel exec faults and out of range accesses,
and put it all in a "bad_kernel_fault()" helper. While at it
test the correct error bits.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:46 +10:00
Benjamin Herrenschmidt
65d47fd4a3 powerpc/mm: Simplify returns from __do_page_fault
Now that we moved the exception state handling to a wrapper, we can
just directly return rather than "goto bail"

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:46 +10:00
Benjamin Herrenschmidt
bb4be50e61 powerpc/mm: Move debugger check to notify_page_fault()
unclutters the main path

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:46 +10:00
Benjamin Herrenschmidt
f3d96e698e powerpc/mm: Overhaul handling of bad page faults
A bad page fault is when the HW signals an error such as a bad
copy/paste, an AMO error, or some other type of error that will
not be fixed by updating the PTE.

Use a helper page_fault_is_bad() to check for bad page faults thus
removing the per-processor family open-coding in __do_page_fault()
and trigger a SIGBUS rather than a SIGSEGV which is more appropriate.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:45 +10:00
Benjamin Herrenschmidt
e6c8290a89 powerpc/mm: Move error_code checks for bad faults earlier
There's no point looking for the VMA etc.. when we already know
we are going to fail.

This adds some code to set "code" for the si_code but that will
be gone in subsequent patches.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:44 +10:00
Benjamin Herrenschmidt
41b464e5e5 powerpc/mm: Move out definition of CPU specific is_write bits
Define a common page_fault_is_write() helper and use it

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:44 +10:00
Benjamin Herrenschmidt
d300627c6a powerpc/6xx: Handle DABR match before calling do_page_fault
On legacy 6xx 32-bit procesors, we checked for the DABR match bit
in DSISR from do_page_fault(), in the middle of a pile of ifdef's
because all other CPU types do it in assembly prior to calling
do_page_fault. Fix that.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Add #ifdef CONFIG_6xx]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:26 +10:00
Benjamin Herrenschmidt
c433ec0455 powerpc/mm: Pre-filter SRR1 bits before do_page_fault()
By filtering the relevant SRR1 bits in the assembly rather than
in do_page_fault() itself, we avoid a conditional branch (since we
already come from different path for data and instruction faults).

This will allow more simplifications later

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-02 13:11:07 +10:00
Benjamin Herrenschmidt
7afad422ac powerpc/mm: Move exception_enter/exit to a do_page_fault wrapper
This will allow simplifying the returns from do_page_fault

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-02 13:11:07 +10:00
Benjamin Herrenschmidt
424de9c6e3 powerpc/mm/radix: Avoid flushing the PWC on every flush_tlb_range
We do that because it's used by THP pmd collapsing, so use
instead a dedicated flush function.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-02 13:11:06 +10:00
Benjamin Herrenschmidt
a46cc7a90f powerpc/mm/radix: Improve TLB/PWC flushes
At the moment we have to rather sub-optimal flushing behaviours:

 - flush_tlb_mm() will flush the PWC which is unnecessary (for example
   when doing a fork)

 - A large unmap will call flush_tlb_pwc() multiple times causing us
   to perform that fairly expensive operation repeatedly. This happens
   often in batches of 3 on every new process.

So we change flush_tlb_mm() to only flush the TLB, and we use the
existing "need_flush_all" flag in struct mmu_gather to indicate
that the PWC needs flushing.

Unfortunately, flush_tlb_range() still needs to do a full flush
for now as it's used by the THP collapsing. We will fix that later.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-02 13:11:06 +10:00
Benjamin Herrenschmidt
5ce5fe14ed powerpc/mm/radix: Improve _tlbiel_pid to be usable for PWC flushes
The PWC flush only needs a single set call, just like the
full (RIC=2) flush.

This will allow us to get rid of the dedicated _tlbiel_pwc()

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-02 13:11:05 +10:00
Michael Ellerman
bb272221e9 Linux v4.13-rc1
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Merge tag 'v4.13-rc1' into fixes

The fixes branch is based off a random pre-rc1 commit, because we had
some fixes that needed to go in before rc1 was released.

However we now need to fix some code that went in after that point, but
before rc1, so merge rc1 to get that code into fixes so we can fix it!
2017-07-31 20:20:29 +10:00
Rui Teng
23493c1219 powerpc/mm: Fix check of multiple 16G pages from device tree
The offset of hugepage block will not be 16G, if the expected
page is more than one. Calculate the totol size instead of the
hardcode value.

Fixes: 4792adbac9 ("powerpc: Don't use a 16G page if beyond mem= limits")
Signed-off-by: Rui Teng <rui.teng@linux.vnet.ibm.com>
Tested-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-31 16:56:58 +10:00
Aneesh Kumar K.V
0da12a7a81 powerpc/mm/hash: Free the subpage_prot_table correctly
Fixes: dad6f37c26 ("powerpc: subpage_protect: Increase the array size to take care of 64TB")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-27 13:05:50 +10:00
Benjamin Herrenschmidt
a25bd72bad powerpc/mm/radix: Workaround prefetch issue with KVM
There's a somewhat architectural issue with Radix MMU and KVM.

When coming out of a guest with AIL (Alternate Interrupt Location, ie,
MMU enabled), we start executing hypervisor code with the PID register
still containing whatever the guest has been using.

The problem is that the CPU can (and will) then start prefetching or
speculatively load from whatever host context has that same PID (if
any), thus bringing translations for that context into the TLB, which
Linux doesn't know about.

This can cause stale translations and subsequent crashes.

Fixing this in a way that is neither racy nor a huge performance
impact is difficult. We could just make the host invalidations always
use broadcast forms but that would hurt single threaded programs for
example.

We chose to fix it instead by partitioning the PID space between guest
and host. This is possible because today Linux only use 19 out of the
20 bits of PID space, so existing guests will work if we make the host
use the top half of the 20 bits space.

We additionally add support for a property to indicate to Linux the
size of the PID register which will be useful if we eventually have
processors with a larger PID space available.

There is still an issue with malicious guests purposefully setting the
PID register to a value in the hosts PID range. Hopefully future HW
can prevent that, but in the meantime, we handle it with a pair of
kludges:

 - On the way out of a guest, before we clear the current VCPU in the
   PACA, we check the PID and if it's outside of the permitted range
   we flush the TLB for that PID.

 - When context switching, if the mm is "new" on that CPU (the
   corresponding bit was set for the first time in the mm cpumask), we
   check if any sibling thread is in KVM (has a non-NULL VCPU pointer
   in the PACA). If that is the case, we also flush the PID for that
   CPU (core).

This second part is needed to handle the case where a process is
migrated (or starts a new pthread) on a sibling thread of the CPU
coming out of KVM, as there's a window where stale translations can
exist before we detect it and flush them out.

A future optimization could be added by keeping track of whether the
PID has ever been used and avoid doing that for completely fresh PIDs.
We could similarily mark PIDs that have been the subject of a global
invalidation as "fresh". But for now this will do.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Rework the asm to build with CONFIG_PPC_RADIX_MMU=n, drop
      unneeded include of kvm_book3s_asm.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-26 16:41:52 +10:00
Aneesh Kumar K.V
7e7dc66adc powerpc/mm: Build fix for non SPARSEMEM_VMEMAP config
We can use pfn_to_page() in realmode for other configs. Hence remove the
CONFIG_FLATMEM ifdef.

Fixes: 8e0861fa3c ("powerpc: Prepare to support kernel handling of IOMMU map/unmap")
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Also fix up the #endif comment]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-24 22:39:08 +10:00
Linus Torvalds
10fc95547f powerpc fixes for 4.13 #3
A handful of fixes, mostly for new code.
 
 Some reworking of the new STRICT_KERNEL_RWX support to make sure we also remove
 executable permission from __init memory before it's freed.
 
 A fix to some recent optimisations to the hypercall entry where we were
 clobbering r12, this was breaking nested guests (PR KVM).
 
 A fix for the recent patch to opal_configure_cores(). This could break booting
 on bare metal Power8 boxes if the kernel was built without
 CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG.
 
 And finally a workaround for spurious PMU interrupts on Power9 DD2.
 
 Thanks to:
   Nicholas Piggin, Anton Blanchard, Balbir Singh.
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Merge tag 'powerpc-4.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "A handful of fixes, mostly for new code:

   - some reworking of the new STRICT_KERNEL_RWX support to make sure we
     also remove executable permission from __init memory before it's
     freed.

   - a fix to some recent optimisations to the hypercall entry where we
     were clobbering r12, this was breaking nested guests (PR KVM).

   - a fix for the recent patch to opal_configure_cores(). This could
     break booting on bare metal Power8 boxes if the kernel was built
     without CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG.

   - .. and finally a workaround for spurious PMU interrupts on Power9
     DD2.

  Thanks to: Nicholas Piggin, Anton Blanchard, Balbir Singh"

* tag 'powerpc-4.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/mm: Mark __init memory no-execute when STRICT_KERNEL_RWX=y
  powerpc/mm/hash: Refactor hash__mark_rodata_ro()
  powerpc/mm/radix: Refactor radix__mark_rodata_ro()
  powerpc/64s: Fix hypercall entry clobbering r12 input
  powerpc/perf: Avoid spurious PMU interrupts after idle
  powerpc/powernv: Fix boot on Power8 bare metal due to opal_configure_cores()
2017-07-21 13:54:37 -07:00
Michael Ellerman
029d9252b1 powerpc/mm: Mark __init memory no-execute when STRICT_KERNEL_RWX=y
Currently even with STRICT_KERNEL_RWX we leave the __init text marked
executable after init, which is bad.

Add a hook to mark it NX (no-execute) before we free it, and implement
it for radix and hash.

Note that we use __init_end as the end address, not _einittext,
because overlaps_kernel_text() uses __init_end, because there are
additional executable sections other than .init.text between
__init_begin and __init_end.

Tested on radix and hash with:

  0:mon> p $__init_begin
  *** 400 exception occurred

Fixes: 1e0fc9d1eb ("powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-18 19:54:24 +10:00
Michael Ellerman
fa7f9189e0 powerpc/mm/hash: Refactor hash__mark_rodata_ro()
Move the core logic into a helper, so we can use it for changing other
permissions.

We also change the logic to align start down, and end up. This means
calling the function with a range will expand that range to be at
least 1 mmu_linear_psize page in size. We need that so we can use it
on __init_begin ...  __init_end which is not a full page in size.

This should always work for _stext/__init_begin, because we align
__init_begin to _stext + 16M in the linker script.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-18 18:51:35 +10:00
Michael Ellerman
b134bd9028 powerpc/mm/radix: Refactor radix__mark_rodata_ro()
Move the core logic into a helper, so we can use it for changing permissions
other than _PAGE_WRITE.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-18 18:51:34 +10:00
Linus Torvalds
deed9deb62 powerpc fixes for 4.13 #2
Nothing that really stands out, just a bunch of fixes that have come in in the
 last couple of weeks.
 
 None of these are actually fixes for code that is new in 4.13. It's roughly half
 older bugs, with fixes going to stable, and half fixes/updates for Power9.
 
 Thanks to:
   Aneesh Kumar K.V, Anton Blanchard, Balbir Singh, Benjamin Herrenschmidt,
   Madhavan Srinivasan, Michael Neuling, Nicholas Piggin, Oliver O'Halloran.
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Merge tag 'powerpc-4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Nothing that really stands out, just a bunch of fixes that have come
  in in the last couple of weeks.

  None of these are actually fixes for code that is new in 4.13. It's
  roughly half older bugs, with fixes going to stable, and half
  fixes/updates for Power9.

  Thanks to: Aneesh Kumar K.V, Anton Blanchard, Balbir Singh, Benjamin
  Herrenschmidt, Madhavan Srinivasan, Michael Neuling, Nicholas Piggin,
  Oliver O'Halloran"

* tag 'powerpc-4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64: Fix atomic64_inc_not_zero() to return an int
  powerpc: Fix emulation of mfocrf in emulate_step()
  powerpc: Fix emulation of mcrf in emulate_step()
  powerpc/perf: Add POWER9 alternate PM_RUN_CYC and PM_RUN_INST_CMPL events
  powerpc/perf: Fix SDAR_MODE value for continous sampling on Power9
  powerpc/asm: Mark cr0 as clobbered in mftb()
  powerpc/powernv: Fix local TLB flush for boot and MCE on POWER9
  powerpc/mm/radix: Synchronize updates to the process table
  powerpc/mm/radix: Properly clear process table entry
  powerpc/powernv: Tell OPAL about our MMU mode on POWER9
  powerpc/kexec: Fix radix to hash kexec due to IAMR/AMOR
2017-07-14 15:33:15 -07:00
Rik van Riel
0a782dc31f powerpc,mmap: properly account for stack randomization in mmap_base
When RLIMIT_STACK is, for example, 256MB, the current code results in a
gap between the top of the task and mmap_base of 256MB, failing to take
into account the amount by which the stack address was randomized.  In
other words, the stack gets less than RLIMIT_STACK space.

Ensure that the gap between the stack and mmap_base always takes stack
randomization and the stack guard gap into account.

Inspired by Daniel Micay's linux-hardened tree.

Link: http://lkml.kernel.org/r/20170622200033.25714-4-riel@redhat.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Florian Weimer <fweimer@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:26:03 -07:00
Benjamin Herrenschmidt
3a6a04706f powerpc/mm/radix: Synchronize updates to the process table
When writing to the process table, we need to ensure the store is
visible to a subsequent access by the MMU. We assume we never have
the PID active while doing the update, so a ptesync/isync pair
should hopefully be a big enough hammer for our purpose.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-10 21:26:31 +10:00
Benjamin Herrenschmidt
c6bb0b8d42 powerpc/mm/radix: Properly clear process table entry
On radix, the process table entry we want to clear when destroying a
context is entry 0, not entry 1. This has no *immediate* consequence
on Power9, but it can cause other bugs to become worse.

Fixes: 7e381c0ff6 ("powerpc/mm/radix: Add mmu context handling callback for radix")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-10 21:24:34 +10:00