Commit Graph

350 Commits

Author SHA1 Message Date
Linus Torvalds
a9c55d58bc powerpc fixes for 5.1 #2
One fix to prevent runtime allocation of 16GB pages when running in a VM (as
 opposed to bare metal), because it doesn't work.
 
 A small fix to our recently added KCOV support to exempt some more code from
 being instrumented.
 
 Plus a few minor build fixes, a small dead code removal and a defconfig update.
 
 Thanks to:
   Alexey Kardashevskiy, Aneesh Kumar K.V, Christophe Leroy, Jason Yan, Joel
   Stanley, Mahesh Salgaonkar, Mathieu Malaterre.
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Merge tag 'powerpc-5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "One fix to prevent runtime allocation of 16GB pages when running in a
  VM (as opposed to bare metal), because it doesn't work.

  A small fix to our recently added KCOV support to exempt some more
  code from being instrumented.

  Plus a few minor build fixes, a small dead code removal and a
  defconfig update.

  Thanks to: Alexey Kardashevskiy, Aneesh Kumar K.V, Christophe Leroy,
  Jason Yan, Joel Stanley, Mahesh Salgaonkar, Mathieu Malaterre"

* tag 'powerpc-5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Include <asm/nmi.h> header file to fix a warning
  powerpc/powernv: Fix compile without CONFIG_TRACEPOINTS
  powerpc/mm: Disable kcov for SLB routines
  powerpc: remove dead code in head_fsl_booke.S
  powerpc/configs: Sync skiroot defconfig
  powerpc/hugetlb: Don't do runtime allocation of 16G pages in LPAR configuration
2019-03-16 10:45:17 -07:00
Linus Torvalds
6c3ac11343 powerpc updates for 5.1
Notable changes:
 
  - Enable THREAD_INFO_IN_TASK to move thread_info off the stack.
 
  - A big series from Christoph reworking our DMA code to use more of the generic
    infrastructure, as he said:
    "This series switches the powerpc port to use the generic swiotlb and
     noncoherent dma ops, and to use more generic code for the coherent direct
     mapping, as well as removing a lot of dead code."
 
  - Increase our vmalloc space to 512T with the Hash MMU on modern CPUs, allowing
    us to support machines with larger amounts of total RAM or distance between
    nodes.
 
  - Two series from Christophe, one to optimise TLB miss handlers on 6xx, and
    another to optimise the way STRICT_KERNEL_RWX is implemented on some 32-bit
    CPUs.
 
  - Support for KCOV coverage instrumentation which means we can run syzkaller
    and discover even more bugs in our code.
 
 And as always many clean-ups, reworks and minor fixes etc.
 
 Thanks to:
  Alan Modra, Alexey Kardashevskiy, Alistair Popple, Andrea Arcangeli, Andrew
  Donnellan, Aneesh Kumar K.V, Aravinda Prasad, Balbir Singh, Brajeswar Ghosh,
  Breno Leitao, Christian Lamparter, Christian Zigotzky, Christophe Leroy,
  Christoph Hellwig, Corentin Labbe, Daniel Axtens, David Gibson, Diana Craciun,
  Firoz Khan, Gustavo A. R. Silva, Igor Stoppa, Joe Lawrence, Joel Stanley,
  Jonathan Neuschäfer, Jordan Niethe, Laurent Dufour, Madhavan Srinivasan, Mahesh
  Salgaonkar, Mark Cave-Ayland, Masahiro Yamada, Mathieu Malaterre, Matteo Croce,
  Meelis Roos, Michael W. Bringmann, Nathan Chancellor, Nathan Fontenot, Nicholas
  Piggin, Nick Desaulniers, Nicolai Stange, Oliver O'Halloran, Paul Mackerras,
  Peter Xu, PrasannaKumar Muralidharan, Qian Cai, Rashmica Gupta, Reza Arbab,
  Robert P. J. Day, Russell Currey, Sabyasachi Gupta, Sam Bobroff, Sandipan Das,
  Sergey Senozhatsky, Souptick Joarder, Stewart Smith, Tyrel Datwyler, Vaibhav
  Jain, YueHaibing.
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Merge tag 'powerpc-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Enable THREAD_INFO_IN_TASK to move thread_info off the stack.

   - A big series from Christoph reworking our DMA code to use more of
     the generic infrastructure, as he said:
       "This series switches the powerpc port to use the generic swiotlb
        and noncoherent dma ops, and to use more generic code for the
        coherent direct mapping, as well as removing a lot of dead
        code."

   - Increase our vmalloc space to 512T with the Hash MMU on modern
     CPUs, allowing us to support machines with larger amounts of total
     RAM or distance between nodes.

   - Two series from Christophe, one to optimise TLB miss handlers on
     6xx, and another to optimise the way STRICT_KERNEL_RWX is
     implemented on some 32-bit CPUs.

   - Support for KCOV coverage instrumentation which means we can run
     syzkaller and discover even more bugs in our code.

  And as always many clean-ups, reworks and minor fixes etc.

  Thanks to: Alan Modra, Alexey Kardashevskiy, Alistair Popple, Andrea
  Arcangeli, Andrew Donnellan, Aneesh Kumar K.V, Aravinda Prasad, Balbir
  Singh, Brajeswar Ghosh, Breno Leitao, Christian Lamparter, Christian
  Zigotzky, Christophe Leroy, Christoph Hellwig, Corentin Labbe, Daniel
  Axtens, David Gibson, Diana Craciun, Firoz Khan, Gustavo A. R. Silva,
  Igor Stoppa, Joe Lawrence, Joel Stanley, Jonathan Neuschäfer, Jordan
  Niethe, Laurent Dufour, Madhavan Srinivasan, Mahesh Salgaonkar, Mark
  Cave-Ayland, Masahiro Yamada, Mathieu Malaterre, Matteo Croce, Meelis
  Roos, Michael W. Bringmann, Nathan Chancellor, Nathan Fontenot,
  Nicholas Piggin, Nick Desaulniers, Nicolai Stange, Oliver O'Halloran,
  Paul Mackerras, Peter Xu, PrasannaKumar Muralidharan, Qian Cai,
  Rashmica Gupta, Reza Arbab, Robert P. J. Day, Russell Currey,
  Sabyasachi Gupta, Sam Bobroff, Sandipan Das, Sergey Senozhatsky,
  Souptick Joarder, Stewart Smith, Tyrel Datwyler, Vaibhav Jain,
  YueHaibing"

* tag 'powerpc-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (200 commits)
  powerpc/32: Clear on-stack exception marker upon exception return
  powerpc: Remove export of save_stack_trace_tsk_reliable()
  powerpc/mm: fix "section_base" set but not used
  powerpc/mm: Fix "sz" set but not used warning
  powerpc/mm: Check secondary hash page table
  powerpc: remove nargs from __SYSCALL
  powerpc/64s: Fix unrelocated interrupt trampoline address test
  powerpc/powernv/ioda: Fix locked_vm counting for memory used by IOMMU tables
  powerpc/fsl: Fix the flush of branch predictor.
  powerpc/powernv: Make opal log only readable by root
  powerpc/xmon: Fix opcode being uninitialized in print_insn_powerpc
  powerpc/powernv: move OPAL call wrapper tracing and interrupt handling to C
  powerpc/64s: Fix data interrupts vs d-side MCE reentrancy
  powerpc/64s: Prepare to handle data interrupts vs d-side MCE reentrancy
  powerpc/64s: system reset interrupt preserve HSRRs
  powerpc/64s: Fix HV NMI vs HV interrupt recoverability test
  powerpc/mm/hash: Handle mmap_min_addr correctly in get_unmapped_area topdown search
  powerpc/hugetlb: Handle mmap_min_addr correctly in get_unmapped_area callback
  selftests/powerpc: Remove duplicate header
  powerpc sstep: Add support for modsd, modud instructions
  ...
2019-03-07 12:56:26 -08:00
Aneesh Kumar K.V
8ef5cbde6d arch/powerpc/mm/hugetlb: NestMMU workaround for hugetlb mprotect RW upgrade
NestMMU requires us to mark the pte invalid and flush the tlb when we do
a RW upgrade of pte.  We fixed a variant of this in the fault path in
bd5050e38a ("powerpc/mm/radix: Change pte relax sequence to handle
nest MMU hang").

Link: http://lkml.kernel.org/r/20190116085035.29729-6-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:18 -08:00
Aneesh Kumar K.V
5b323367ef arch/powerpc/mm: Nest MMU workaround for mprotect RW upgrade
NestMMU requires us to mark the pte invalid and flush the tlb when we do
a RW upgrade of pte.  We fixed a variant of this in the fault path in
bd5050e38a ("powerpc/mm/radix: Change pte relax sequence to handle
nest MMU hang").

Do the same for mprotect upgrades.

Hugetlb is handled in the next patch.

Link: http://lkml.kernel.org/r/20190116085035.29729-4-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:18 -08:00
Aneesh Kumar K.V
35f2806b48 powerpc/hugetlb: Don't do runtime allocation of 16G pages in LPAR configuration
We added runtime allocation of 16G pages in commit 4ae279c2c9
("powerpc/mm/hugetlb: Allow runtime allocation of 16G.") That was done
to enable 16G allocation on PowerNV and KVM config. In case of KVM
config, we mostly would have the entire guest RAM backed by 16G
hugetlb pages for this to work. PAPR do support partial backing of
guest RAM with hugepages via ibm,expected#pages node of memory node in
the device tree. This means rest of the guest RAM won't be backed by
16G contiguous pages in the host and hence a hash page table insertion
can fail in such case.

An example error message will look like

  hash-mmu: mm: Hashing failure ! EA=0x7efc00000000 access=0x8000000000000006 current=readback
  hash-mmu:     trap=0x300 vsid=0x67af789 ssize=1 base psize=14 psize 14 pte=0xc000000400000386
  readback[12260]: unhandled signal 7 at 00007efc00000000 nip 00000000100012d0 lr 000000001000127c code 2

This patch address that by preventing runtime allocation of 16G
hugepages in LPAR config. To allocate 16G hugetlb one need to kernel
command line hugepagesz=16G hugepages=<number of 16G pages>

With radix translation mode we don't run into this issue.

This change will prevent runtime allocation of 16G hugetlb pages on
kvm with hash translation mode. However, with the current upstream it
was observed that 16G hugetlbfs backed guest doesn't boot at all.

We observe boot failure with the below message:
  [131354.647546] KVM: map_vrma at 0 failed, ret=-4

That means this patch is not resulting in an observable regression.
Once we fix the boot issue with 16G hugetlb backed memory, we need to
use ibm,expected#pages memory node attribute to indicate 16G page
reservation to the guest. This will also enable partial backing of
guest RAM with 16G pages.

Fixes: 4ae279c2c9 ("powerpc/mm/hugetlb: Allow runtime allocation of 16G.")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-03-05 15:52:42 +11:00
Christophe Leroy
92ab45c5f2 powerpc: Avoid circular header inclusion in mmu-hash.h
When activating CONFIG_THREAD_INFO_IN_TASK, linux/sched.h includes
asm/current.h. This generates a circular dependency. To avoid that,
asm/processor.h shall not be included in mmu-hash.h.

In order to do that, this patch moves into a new header called
asm/task_size_64/32.h all the TASK_SIZE related constants, which can
then be included in mmu-hash.h directly.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out all the TASK_SIZE constants not just 64-bit ones]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:39 +11:00
Christophe Leroy
63b2bc6195 powerpc/mm/32s: Use BATs for STRICT_KERNEL_RWX
Today, STRICT_KERNEL_RWX is based on the use of regular pages
to map kernel pages.

On Book3s 32, it has three consequences:
- Using pages instead of BAT for mapping kernel linear memory severely
impacts performance.
- Exec protection is not effective because no-execute cannot be set at
page level (except on 603 which doesn't have hash tables)
- Write protection is not effective because PP bits do not provide RO
mode for kernel-only pages (except on 603 which handles it in software
via PAGE_DIRTY)

On the 603+, we have:
- Independent IBAT and DBAT allowing limitation of exec parts.
- NX bit can be set in segment registers to forbit execution on memory
mapped by pages.
- RO mode on DBATs even for kernel-only blocks.

On the 601, there is nothing much we can do other than warn the user
about it, because:
- BATs are common to instructions and data.
- BAT do not provide RO mode for kernel-only blocks.
- segment registers don't have the NX bit.

In order to use IBAT for exec protection, this patch:
- Aligns _etext to BAT block sizes (128kb)
- Set NX bit in kernel segment register (Except on vmalloc area when
CONFIG_MODULES is selected)
- Maps kernel text with IBATs.

In order to use DBAT for exec protection, this patch:
- Aligns RW DATA to BAT block sizes (4M)
- Maps kernel RO area with write prohibited DBATs
- Maps remaining memory with remaining DBATs

Here is what we get with this patch on a 832x when activating
STRICT_KERNEL_RWX:

Symbols:
c0000000 T _stext
c0680000 R __start_rodata
c0680000 R _etext
c0800000 T __init_begin
c0800000 T _sinittext

~# cat /sys/kernel/debug/block_address_translation
---[ Instruction Block Address Translation ]---
0: 0xc0000000-0xc03fffff 0x00000000 Kernel EXEC coherent
1: 0xc0400000-0xc05fffff 0x00400000 Kernel EXEC coherent
2: 0xc0600000-0xc067ffff 0x00600000 Kernel EXEC coherent
3:         -
4:         -
5:         -
6:         -
7:         -

---[ Data Block Address Translation ]---
0: 0xc0000000-0xc07fffff 0x00000000 Kernel RO coherent
1: 0xc0800000-0xc0ffffff 0x00800000 Kernel RW coherent
2: 0xc1000000-0xc1ffffff 0x01000000 Kernel RW coherent
3: 0xc2000000-0xc3ffffff 0x02000000 Kernel RW coherent
4: 0xc4000000-0xc7ffffff 0x04000000 Kernel RW coherent
5: 0xc8000000-0xcfffffff 0x08000000 Kernel RW coherent
6: 0xd0000000-0xdfffffff 0x10000000 Kernel RW coherent
7:         -

~# cat /sys/kernel/debug/segment_registers
---[ User Segments ]---
0x00000000-0x0fffffff Kern key 1 User key 1 VSID 0xa085d0
0x10000000-0x1fffffff Kern key 1 User key 1 VSID 0xa086e1
0x20000000-0x2fffffff Kern key 1 User key 1 VSID 0xa087f2
0x30000000-0x3fffffff Kern key 1 User key 1 VSID 0xa08903
0x40000000-0x4fffffff Kern key 1 User key 1 VSID 0xa08a14
0x50000000-0x5fffffff Kern key 1 User key 1 VSID 0xa08b25
0x60000000-0x6fffffff Kern key 1 User key 1 VSID 0xa08c36
0x70000000-0x7fffffff Kern key 1 User key 1 VSID 0xa08d47
0x80000000-0x8fffffff Kern key 1 User key 1 VSID 0xa08e58
0x90000000-0x9fffffff Kern key 1 User key 1 VSID 0xa08f69
0xa0000000-0xafffffff Kern key 1 User key 1 VSID 0xa0907a
0xb0000000-0xbfffffff Kern key 1 User key 1 VSID 0xa0918b

---[ Kernel Segments ]---
0xc0000000-0xcfffffff Kern key 0 User key 1 No Exec VSID 0x000ccc
0xd0000000-0xdfffffff Kern key 0 User key 1 No Exec VSID 0x000ddd
0xe0000000-0xefffffff Kern key 0 User key 1 No Exec VSID 0x000eee
0xf0000000-0xffffffff Kern key 0 User key 1 No Exec VSID 0x000fff

Aligning _etext to 128kb allows to map up to 32Mb text with 8 IBATs:
16Mb + 8Mb + 4Mb + 2Mb + 1Mb + 512kb + 256kb + 128kb (+ 128kb) = 32Mb
(A 9th IBAT is unneeded as 32Mb would need only a single 32Mb block)

Aligning data to 4M allows to map up to 512Mb data with 8 DBATs:
16Mb + 8Mb + 4Mb + 4Mb + 32Mb + 64Mb + 128Mb + 256Mb = 512Mb

Because some processors only have 4 BATs and because some targets need
DBATs for mapping other areas, the following patch will allow to
modify _etext and data alignment.

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>
2019-02-23 21:04:32 +11:00
Christophe Leroy
5e04ae85fb powerpc/mm/32s: add setibat() clearibat() and update_bats()
setibat() and clearibat() allows to manipulate IBATs independently
of DBATs.

update_bats() allows to update bats after init. This is done
with MMU off.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Michael Ellerman
f68e792721 Revert "powerpc/book3s32: Reorder _PAGE_XXX flags to simplify TLB handling"
This reverts commit 78ca1108b1.

It is causing boot failures with qemu mac99 in at least some
configurations.
2019-02-23 20:30:50 +11:00
Christophe Leroy
78ca1108b1 powerpc/book3s32: Reorder _PAGE_XXX flags to simplify TLB handling
For pages without _PAGE_USER, PP field is 00
For pages with _PAGE_USER, PP field is 10 for RW and 11 for RO.

This patch sets _PAGE_USER to 0x002 and _PAGE_RW to 0x001
is order to simplify TLB handling by reducing amount of shifts.

The location of _PAGE_PRESENT and _PAGE_HASHPTE doesn't matter
as they are only SW related flags.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00
Aneesh Kumar K.V
c746ca00f5 powerpc/book3s: Remove pgd/pud/pmd_set() interfaces
When updating page tables, we need to make sure we fill the page table
entry valid bits. We do this by or'ing in one of PGD/PUD/PMD_VAL_BITS.

The page table 'set' interfaces allow updating the raw value of page
table entries without setting the valid bits, so remove those
interfaces to avoid incorrect usage in future.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Reword commit message based on mailing list discussion]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:15 +11:00
Michael Ellerman
3d8810e02b powerpc/mm/hash: Increase vmalloc space to 512T with hash MMU
This patch updates the kernel non-linear virtual map to 512TB when
we're built with 64K page size and are using the hash MMU. We allocate
one context for the vmalloc region and hence the max virtual area size
is limited by the context map size (512TB for 64K and 64TB for 4K page
size).

This patch fixes boot failures with large amounts of system RAM where
we need large vmalloc space to handle per cpu allocations.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
2019-02-22 00:10:14 +11:00
Michael Ellerman
637cfeb9f9 Merge branch 'fixes' into next
There's a few important fixes in our fixes branch, in particular the
pgd/pud_present() one, so merge it now.
2019-02-19 19:56:26 +11:00
Michael Ellerman
a58007621b powerpc/64s: Fix possible corruption on big endian due to pgd/pud_present()
In v4.20 we changed our pgd/pud_present() to check for _PAGE_PRESENT
rather than just checking that the value is non-zero, e.g.:

  static inline int pgd_present(pgd_t pgd)
  {
 -       return !pgd_none(pgd);
 +       return (pgd_raw(pgd) & cpu_to_be64(_PAGE_PRESENT));
  }

Unfortunately this is broken on big endian, as the result of the
bitwise & is truncated to int, which is always zero because
_PAGE_PRESENT is 0x8000000000000000ul. This means pgd_present() and
pud_present() are always false at compile time, and the compiler
elides the subsequent code.

Remarkably with that bug present we are still able to boot and run
with few noticeable effects. However under some work loads we are able
to trigger a warning in the ext4 code:

  WARNING: CPU: 11 PID: 29593 at fs/ext4/inode.c:3927 .ext4_set_page_dirty+0x70/0xb0
  CPU: 11 PID: 29593 Comm: debugedit Not tainted 4.20.0-rc1 #1
  ...
  NIP .ext4_set_page_dirty+0x70/0xb0
  LR  .set_page_dirty+0xa0/0x150
  Call Trace:
   .set_page_dirty+0xa0/0x150
   .unmap_page_range+0xbf0/0xe10
   .unmap_vmas+0x84/0x130
   .unmap_region+0xe8/0x190
   .__do_munmap+0x2f0/0x510
   .__vm_munmap+0x80/0x110
   .__se_sys_munmap+0x14/0x30
   system_call+0x5c/0x70

The fix is simple, we need to convert the result of the bitwise & to
an int before returning it.

Thanks to Erhard, Jan Kara and Aneesh for help with debugging.

Fixes: da7ad366b4 ("powerpc/mm/book3s: Update pmd_present to look at _PAGE_PRESENT bit")
Cc: stable@vger.kernel.org # v4.20+
Reported-by: Erhard F. <erhard_f@mailbox.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-17 15:24:45 +11:00
Aneesh Kumar K.V
579b9239c1 powerpc/radix: Fix kernel crash with mremap()
With support for split pmd lock, we use pmd page pmd_huge_pte pointer
to store the deposited page table. In those config when we move page
tables we need to make sure we move the deposited page table to the
correct pmd page. Otherwise this can result in crash when we withdraw
of deposited page table because we can find the pmd_huge_pte NULL.

eg:

  __split_huge_pmd+0x1070/0x1940
  __split_huge_pmd+0xe34/0x1940 (unreliable)
  vma_adjust_trans_huge+0x110/0x1c0
  __vma_adjust+0x2b4/0x9b0
  __split_vma+0x1b8/0x280
  __do_munmap+0x13c/0x550
  sys_mremap+0x220/0x7e0
  system_call+0x5c/0x70

Fixes: 675d995297 ("powerpc/book3s64: Enable split pmd ptlock.")
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-31 20:10:15 +11:00
Reza Arbab
865a9432d1 powerpc/mm: Add _PAGE_SAO to _PAGE_CACHE_CTL mask
In htab_convert_pte_flags(), _PAGE_CACHE_CTL is used to check for the
_PAGE_SAO flag:

  else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_SAO)
          rflags |= (HPTE_R_W | HPTE_R_I | HPTE_R_M);

But, it isn't defined to include that flag:

  #define _PAGE_CACHE_CTL (_PAGE_NON_IDEMPOTENT | _PAGE_TOLERANT)

This happens to work, but only because of the flag values:

  #define _PAGE_SAO               0x00010 /* Strong access order */
  #define _PAGE_NON_IDEMPOTENT    0x00020 /* non idempotent memory */
  #define _PAGE_TOLERANT          0x00030 /* tolerant memory, cache inhibited */

To prevent any issues if these particulars ever change, add _PAGE_SAO to
the mask.

Suggested-by: Charles Johns <crjohns@us.ibm.com>
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-31 00:36:06 +11:00
Alexey Kardashevskiy
cd6b8a631c powerpc/mm: Fix compile when CONFIG_PPC_RADIX_MMU is not defined
This adds some stubs for hash only configs.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-15 11:17:09 +11:00
Joel Fernandes (Google)
4cf5892495 mm: treewide: remove unused address argument from pte_alloc functions
Patch series "Add support for fast mremap".

This series speeds up the mremap(2) syscall by copying page tables at
the PMD level even for non-THP systems.  There is concern that the extra
'address' argument that mremap passes to pte_alloc may do something
subtle architecture related in the future that may make the scheme not
work.  Also we find that there is no point in passing the 'address' to
pte_alloc since its unused.  This patch therefore removes this argument
tree-wide resulting in a nice negative diff as well.  Also ensuring
along the way that the enabled architectures do not do anything funky
with the 'address' argument that goes unnoticed by the optimization.

Build and boot tested on x86-64.  Build tested on arm64.  The config
enablement patch for arm64 will be posted in the future after more
testing.

The changes were obtained by applying the following Coccinelle script.
(thanks Julia for answering all Coccinelle questions!).
Following fix ups were done manually:
* Removal of address argument from  pte_fragment_alloc
* Removal of pte_alloc_one_fast definitions from m68k and microblaze.

// Options: --include-headers --no-includes
// Note: I split the 'identifier fn' line, so if you are manually
// running it, please unsplit it so it runs for you.

virtual patch

@pte_alloc_func_def depends on patch exists@
identifier E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
type T2;
@@

 fn(...
- , T2 E2
 )
 { ... }

@pte_alloc_func_proto_noarg depends on patch exists@
type T1, T2, T3, T4;
identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1, T2);
+ T3 fn(T1);
|
- T3 fn(T1, T2, T4);
+ T3 fn(T1, T2);
)

@pte_alloc_func_proto depends on patch exists@
identifier E1, E2, E4;
type T1, T2, T3, T4;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1 E1, T2 E2);
+ T3 fn(T1 E1);
|
- T3 fn(T1 E1, T2 E2, T4 E4);
+ T3 fn(T1 E1, T2 E2);
)

@pte_alloc_func_call depends on patch exists@
expression E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

 fn(...
-,  E2
 )

@pte_alloc_macro depends on patch exists@
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
identifier a, b, c;
expression e;
position p;
@@

(
- #define fn(a, b, c) e
+ #define fn(a, b) e
|
- #define fn(a, b) e
+ #define fn(a) e
)

Link: http://lkml.kernel.org/r/20181108181201.88826-2-joelaf@google.com
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Suggested-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-04 13:13:47 -08:00
Michael Ellerman
423e2f9445 powerpc/mm: Remove very old comment in hash-4k.h
This comment talks about PTEs being 64-bits and PMD/PGD being 32-bits,
but that hasn't been true since 2005 when David Gibson implemented
4-level page tables in the commit titled "Four level pagetables for
ppc64".

Remove it.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-22 21:04:27 +11:00
Christophe Leroy
385e89d5b2 powerpc/mm: add exec protection on powerpc 603
The 603 doesn't have a HASH table, TLB misses are handled by
software. It is then possible to generate page fault when
_PAGE_EXEC is not set like in nohash/32.

There is one "reserved" PTE bit available, this patch uses
it for _PAGE_EXEC.

In order to support it, set_pte_filter() and
set_access_flags_filter() are made common, and the handling
is made dependent on MMU_FTR_HPTE_TABLE

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy
9efc74ff52 powerpc/book3s/32: Use patch_site to patch hash functions
Use patch_sites and the new modify_instruction_site() function
instead of hardcoding hash functions patching.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy
7c91efce16 powerpc/mm: dump block address translation on book3s/32
This patch adds a debugfs file to dump block address translation:

~# cat /sys/kernel/debug/powerpc/block_address_translation
---[ Instruction Block Address Translations ]---
0:         -
1:         -
2: 0xc0000000-0xcfffffff 0x00000000 Kernel EXEC coherent
3: 0xd0000000-0xdfffffff 0x10000000 Kernel EXEC coherent
4:         -
5:         -
6:         -
7:         -

---[ Data Block Address Translations ]---
0:         -
1:         -
2: 0xc0000000-0xcfffffff 0x00000000 Kernel RW coherent
3: 0xd0000000-0xdfffffff 0x10000000 Kernel RW coherent
4:         -
5:         -
6:         -
7:         -

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

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:46:49 +11:00
Christophe Leroy
129dd323dd powerpc/mm: enable the use of page table cache of order 0
hugepages uses a cache of order 0. Lets allow page tables
of order 0 in the common part in order to avoid open coding
in hugetlb

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy
32ea4c1499 powerpc/mm: Extend pte_fragment functionality to PPC32
In order to allow the 8xx to handle pte_fragments, this patch
extends the use of pte_fragments to PPC32 platforms.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy
d09780f3a8 powerpc/mm: Move pgtable_t into platform headers
This patch move pgtable_t into platform headers.

It gets rid of the CONFIG_PPC_64K_PAGES case for PPC64
as nohash/64 doesn't support CONFIG_PPC_64K_PAGES.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy
a95d133c86 powerpc/mm: Move pte_fragment_alloc() to a common location
In preparation of next patch which generalises the use of
pte_fragment_alloc() for all, this patch moves the related functions
in a place that is common to all subarches.

The 8xx will need that for supporting 16k pages, as in that mode
page tables still have a size of 4k.

Since pte_fragment with only once fragment is not different
from what is done in the general case, we can easily migrate all
subarchs to pte fragments.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy
a43ccc4bc4 powerpc/book3s32: Remove CONFIG_BOOKE dependent code
BOOK3S/32 cannot be BOOKE, so remove useless code

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy
a0cd0f8cab powerpc/32: Remove #ifdef CONFIG_PPC_STD_MMU_32 in asm/book3s/32/pgtable.h
asm/book3s/32/pgtable.h is only included when CONFIG_PPC_BOOK3S_32 is set.
Whenever CONFIG_PPC_BOOK3S_32 is set, CONFIG_PPC_STD_MMU_32 is set as well.

This patch removes useless CONFIG_PPC_STD_MMU_32 #ifdefs

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-26 22:33:37 +11:00
Mathieu Malaterre
c516886f84 powerpc/mm: remove const type qualifier from function ‘pud_pfn’
Type qualifier on return type is ignored. Remove warning in W=1:

  arch/powerpc/include/asm/book3s/64/pgtable.h:1268:25: error: type qualifiers ignored on function return type [-Werror=ignored-qualifiers]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-25 17:11:22 +11:00
Linus Torvalds
dad4f140ed Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax
Pull XArray conversion from Matthew Wilcox:
 "The XArray provides an improved interface to the radix tree data
  structure, providing locking as part of the API, specifying GFP flags
  at allocation time, eliminating preloading, less re-walking the tree,
  more efficient iterations and not exposing RCU-protected pointers to
  its users.

  This patch set

   1. Introduces the XArray implementation

   2. Converts the pagecache to use it

   3. Converts memremap to use it

  The page cache is the most complex and important user of the radix
  tree, so converting it was most important. Converting the memremap
  code removes the only other user of the multiorder code, which allows
  us to remove the radix tree code that supported it.

  I have 40+ followup patches to convert many other users of the radix
  tree over to the XArray, but I'd like to get this part in first. The
  other conversions haven't been in linux-next and aren't suitable for
  applying yet, but you can see them in the xarray-conv branch if you're
  interested"

* 'xarray' of git://git.infradead.org/users/willy/linux-dax: (90 commits)
  radix tree: Remove multiorder support
  radix tree test: Convert multiorder tests to XArray
  radix tree tests: Convert item_delete_rcu to XArray
  radix tree tests: Convert item_kill_tree to XArray
  radix tree tests: Move item_insert_order
  radix tree test suite: Remove multiorder benchmarking
  radix tree test suite: Remove __item_insert
  memremap: Convert to XArray
  xarray: Add range store functionality
  xarray: Move multiorder_check to in-kernel tests
  xarray: Move multiorder_shrink to kernel tests
  xarray: Move multiorder account test in-kernel
  radix tree test suite: Convert iteration test to XArray
  radix tree test suite: Convert tag_tagged_items to XArray
  radix tree: Remove radix_tree_clear_tags
  radix tree: Remove radix_tree_maybe_preload_order
  radix tree: Remove split/join code
  radix tree: Remove radix_tree_update_node_t
  page cache: Finish XArray conversion
  dax: Convert page fault handlers to XArray
  ...
2018-10-28 11:35:40 -07:00
Linus Torvalds
345671ea0f Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc things

 - ocfs2 updates

 - most of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (132 commits)
  hugetlbfs: dirty pages as they are added to pagecache
  mm: export add_swap_extent()
  mm: split SWP_FILE into SWP_ACTIVATED and SWP_FS
  tools/testing/selftests/vm/map_fixed_noreplace.c: add test for MAP_FIXED_NOREPLACE
  mm: thp: relocate flush_cache_range() in migrate_misplaced_transhuge_page()
  mm: thp: fix mmu_notifier in migrate_misplaced_transhuge_page()
  mm: thp: fix MADV_DONTNEED vs migrate_misplaced_transhuge_page race condition
  mm/kasan/quarantine.c: make quarantine_lock a raw_spinlock_t
  mm/gup: cache dev_pagemap while pinning pages
  Revert "x86/e820: put !E820_TYPE_RAM regions into memblock.reserved"
  mm: return zero_resv_unavail optimization
  mm: zero remaining unavailable struct pages
  tools/testing/selftests/vm/gup_benchmark.c: add MAP_HUGETLB option
  tools/testing/selftests/vm/gup_benchmark.c: add MAP_SHARED option
  tools/testing/selftests/vm/gup_benchmark.c: allow user specified file
  tools/testing/selftests/vm/gup_benchmark.c: fix 'write' flag usage
  mm/gup_benchmark.c: add additional pinning methods
  mm/gup_benchmark.c: time put_page()
  mm: don't raise MEMCG_OOM event due to failed high-order allocation
  mm/page-writeback.c: fix range_cyclic writeback vs writepages deadlock
  ...
2018-10-26 19:33:41 -07:00
Alexandre Ghiti
8e581d433b hugetlb: introduce generic version of huge_ptep_set_wrprotect()
arm, ia64, mips, powerpc, sh, x86 architectures use the same version of
huge_ptep_set_wrprotect, so move this generic implementation into
asm-generic/hugetlb.h.

Link: http://lkml.kernel.org/r/20180920060358.16606-10-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Tested-by: Helge Deller <deller@gmx.de>			[parisc]
Acked-by: Catalin Marinas <catalin.marinas@arm.com>	[arm64]
Acked-by: Paul Burton <paul.burton@mips.com>		[MIPS]
Acked-by: Ingo Molnar <mingo@kernel.org>		[x86]
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:26:34 -07:00
Linus Torvalds
685f7e4f16 powerpc updates for 4.20
Notable changes:
 
  - A large series to rewrite our SLB miss handling, replacing a lot of fairly
    complicated asm with much fewer lines of C.
 
  - Following on from that, we now maintain a cache of SLB entries for each
    process and preload them on context switch. Leading to a 27% speedup for our
    context switch benchmark on Power9.
 
  - Improvements to our handling of SLB multi-hit errors. We now print more debug
    information when they occur, and try to continue running by flushing the SLB
    and reloading, rather than treating them as fatal.
 
  - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).
 
  - Add support for physical memory up to 2PB in the linear mapping on 64-bit
    Book3S. We only support up to 512TB as regular system memory, otherwise the
    percpu allocator runs out of vmalloc space.
 
  - Add stack protector support for 32 and 64-bit, with a per-task canary.
 
  - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.
 
  - Support recognising "big cores" on Power9, where two SMT4 cores are presented
    to us as a single SMT8 core.
 
  - A large series to cleanup some of our ioremap handling and PTE flags.
 
  - Add a driver for the PAPR SCM (storage class memory) interface, allowing
    guests to operate on SCM devices (acked by Dan).
 
  - Changes to our ftrace code to handle very large kernels, where we need to use
    a trampoline to get to ftrace_caller().
 
 Many other smaller enhancements and cleanups.
 
 Thanks to:
   Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton Blanchard, Aravinda
   Prasad, Bartlomiej Zolnierkiewicz, Benjamin Herrenschmidt, Breno Leitao,
   Cédric Le Goater, Christophe Leroy, Christophe Lombard, Dan Carpenter, Daniel
   Axtens, Finn Thain, Gautham R. Shenoy, Gustavo Romero, Haren Myneni, Hari
   Bathini, Jia Hongtao, Joel Stanley, John Allen, Laurent Dufour, Madhavan
   Srinivasan, Mahesh Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael
   Bringmann, Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
   Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran,
   Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab, Rob Herring, Sam
   Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan Johnson, Stephen Rothwell,
   Stewart Smith, Suraj Jitindar Singh, Tyrel Datwyler, Vaibhav Jain, Vasant
   Hegde, YueHaibing, zhong jiang,
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Merge tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - A large series to rewrite our SLB miss handling, replacing a lot of
     fairly complicated asm with much fewer lines of C.

   - Following on from that, we now maintain a cache of SLB entries for
     each process and preload them on context switch. Leading to a 27%
     speedup for our context switch benchmark on Power9.

   - Improvements to our handling of SLB multi-hit errors. We now print
     more debug information when they occur, and try to continue running
     by flushing the SLB and reloading, rather than treating them as
     fatal.

   - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).

   - Add support for physical memory up to 2PB in the linear mapping on
     64-bit Book3S. We only support up to 512TB as regular system
     memory, otherwise the percpu allocator runs out of vmalloc space.

   - Add stack protector support for 32 and 64-bit, with a per-task
     canary.

   - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.

   - Support recognising "big cores" on Power9, where two SMT4 cores are
     presented to us as a single SMT8 core.

   - A large series to cleanup some of our ioremap handling and PTE
     flags.

   - Add a driver for the PAPR SCM (storage class memory) interface,
     allowing guests to operate on SCM devices (acked by Dan).

   - Changes to our ftrace code to handle very large kernels, where we
     need to use a trampoline to get to ftrace_caller().

  And many other smaller enhancements and cleanups.

  Thanks to: Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton
  Blanchard, Aravinda Prasad, Bartlomiej Zolnierkiewicz, Benjamin
  Herrenschmidt, Breno Leitao, Cédric Le Goater, Christophe Leroy,
  Christophe Lombard, Dan Carpenter, Daniel Axtens, Finn Thain, Gautham
  R. Shenoy, Gustavo Romero, Haren Myneni, Hari Bathini, Jia Hongtao,
  Joel Stanley, John Allen, Laurent Dufour, Madhavan Srinivasan, Mahesh
  Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael Bringmann,
  Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
  Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver
  O'Halloran, Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab,
  Rob Herring, Sam Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan
  Johnson, Stephen Rothwell, Stewart Smith, Suraj Jitindar Singh, Tyrel
  Datwyler, Vaibhav Jain, Vasant Hegde, YueHaibing, zhong jiang"

* tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (221 commits)
  Revert "selftests/powerpc: Fix out-of-tree build errors"
  powerpc/msi: Fix compile error on mpc83xx
  powerpc: Fix stack protector crashes on CPU hotplug
  powerpc/traps: restore recoverability of machine_check interrupts
  powerpc/64/module: REL32 relocation range check
  powerpc/64s/radix: Fix radix__flush_tlb_collapsed_pmd double flushing pmd
  selftests/powerpc: Add a test of wild bctr
  powerpc/mm: Fix page table dump to work on Radix
  powerpc/mm/radix: Display if mappings are exec or not
  powerpc/mm/radix: Simplify split mapping logic
  powerpc/mm/radix: Remove the retry in the split mapping logic
  powerpc/mm/radix: Fix small page at boundary when splitting
  powerpc/mm/radix: Fix overuse of small pages in splitting logic
  powerpc/mm/radix: Fix off-by-one in split mapping logic
  powerpc/ftrace: Handle large kernel configs
  powerpc/mm: Fix WARN_ON with THP NUMA migration
  selftests/powerpc: Fix out-of-tree build errors
  powerpc/time: no steal_time when CONFIG_PPC_SPLPAR is not selected
  powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64
  powerpc/time: isolate scaled cputime accounting in dedicated functions.
  ...
2018-10-26 14:36:21 -07:00
Linus Torvalds
0d1e8b8d2b KVM updates for v4.20
ARM:
  - Improved guest IPA space support (32 to 52 bits)
 
  - RAS event delivery for 32bit
 
  - PMU fixes
 
  - Guest entry hardening
 
  - Various cleanups
 
  - Port of dirty_log_test selftest
 
 PPC:
  - Nested HV KVM support for radix guests on POWER9.  The performance is
    much better than with PR KVM.  Migration and arbitrary level of
    nesting is supported.
 
  - Disable nested HV-KVM on early POWER9 chips that need a particular hardware
    bug workaround
 
  - One VM per core mode to prevent potential data leaks
 
  - PCI pass-through optimization
 
  - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base
 
 s390:
  - Initial version of AP crypto virtualization via vfio-mdev
 
  - Improvement for vfio-ap
 
  - Set the host program identifier
 
  - Optimize page table locking
 
 x86:
  - Enable nested virtualization by default
 
  - Implement Hyper-V IPI hypercalls
 
  - Improve #PF and #DB handling
 
  - Allow guests to use Enlightened VMCS
 
  - Add migration selftests for VMCS and Enlightened VMCS
 
  - Allow coalesced PIO accesses
 
  - Add an option to perform nested VMCS host state consistency check
    through hardware
 
  - Automatic tuning of lapic_timer_advance_ns
 
  - Many fixes, minor improvements, and cleanups
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Merge tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "ARM:
   - Improved guest IPA space support (32 to 52 bits)

   - RAS event delivery for 32bit

   - PMU fixes

   - Guest entry hardening

   - Various cleanups

   - Port of dirty_log_test selftest

  PPC:
   - Nested HV KVM support for radix guests on POWER9. The performance
     is much better than with PR KVM. Migration and arbitrary level of
     nesting is supported.

   - Disable nested HV-KVM on early POWER9 chips that need a particular
     hardware bug workaround

   - One VM per core mode to prevent potential data leaks

   - PCI pass-through optimization

   - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base

  s390:
   - Initial version of AP crypto virtualization via vfio-mdev

   - Improvement for vfio-ap

   - Set the host program identifier

   - Optimize page table locking

  x86:
   - Enable nested virtualization by default

   - Implement Hyper-V IPI hypercalls

   - Improve #PF and #DB handling

   - Allow guests to use Enlightened VMCS

   - Add migration selftests for VMCS and Enlightened VMCS

   - Allow coalesced PIO accesses

   - Add an option to perform nested VMCS host state consistency check
     through hardware

   - Automatic tuning of lapic_timer_advance_ns

   - Many fixes, minor improvements, and cleanups"

* tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
  KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned
  Revert "kvm: x86: optimize dr6 restore"
  KVM: PPC: Optimize clearing TCEs for sparse tables
  x86/kvm/nVMX: tweak shadow fields
  selftests/kvm: add missing executables to .gitignore
  KVM: arm64: Safety check PSTATE when entering guest and handle IL
  KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chips
  arm/arm64: KVM: Enable 32 bits kvm vcpu events support
  arm/arm64: KVM: Rename function kvm_arch_dev_ioctl_check_extension()
  KVM: arm64: Fix caching of host MDCR_EL2 value
  KVM: VMX: enable nested virtualization by default
  KVM/x86: Use 32bit xor to clear registers in svm.c
  kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD
  kvm: vmx: Defer setting of DR6 until #DB delivery
  kvm: x86: Defer setting of CR2 until #PF delivery
  kvm: x86: Add payload operands to kvm_multiple_exception
  kvm: x86: Add exception payload fields to kvm_vcpu_events
  kvm: x86: Add has_payload and payload to kvm_queued_exception
  KVM: Documentation: Fix omission in struct kvm_vcpu_events
  KVM: selftests: add Enlightened VMCS test
  ...
2018-10-25 17:57:35 -07:00
Aneesh Kumar K.V
b9fb4480a3 powerpc/mm: Make pte_pgprot return all pte bits
Other archs do the same and instead of adding required pte bits (which
got masked out) in __ioremap_at(), make sure we filter only pfn bits
out.

Fixes: 26973fa5ac ("powerpc/mm: use pte helpers in generic code")
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-19 00:56:17 +11:00
Aneesh Kumar K.V
4ffe713b75 powerpc/mm: Increase the max addressable memory to 2PB
Currently we limit the max addressable memory to 128TB. This patch increase the
limit to 2PB. We can have devices like nvdimm which adds memory above 512TB
limit.

We still don't support regular system ram above 512TB. One of the challenge with
that is the percpu allocator, that allocates per node memory and use the max
distance between them as the percpu offsets. This means with large gap in
address space ( system ram above 1PB) we will run out of vmalloc space to map
the percpu allocation.

In order to support addressable memory above 512TB, kernel should be able to
linear map this range. To do that with hash translation we now add 4 context
to kernel linear map region. Our per context addressable range is 512TB. We
still keep VMALLOC and VMEMMAP region to old size. SLB miss handlers is updated
to validate these limit.

We also limit this update to SPARSEMEM_VMEMMAP and SPARSEMEM_EXTREME

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Aneesh Kumar K.V
c9f80734cd powerpc/mm/hash: Rename get_ea_context to get_user_context
We will be adding get_kernel_context later. Update function name to indicate
this handle context allocation user space address.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Nicholas Piggin
94ee42727c powerpc/64s/hash: Simplify slb_flush_and_rebolt()
slb_flush_and_rebolt() is misleading, it is called in virtual mode, so
it can not possibly change the stack, so it should not be touching the
shadow area. And since vmalloc is no longer bolted, it should not
change any bolted mappings at all.

Change the name to slb_flush_and_restore_bolted(), and have it just
load the kernel stack from what's currently in the shadow SLB area.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Nicholas Piggin
425d331462 powerpc/64s/hash: Provide arch_setup_exec() hooks for hash slice setup
This will be used by the SLB code in the next patch, but for now this
sets the slb_addr_limit to the correct size for 32-bit tasks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Christophe Leroy
1b2443a547 powerpc/book3s64: Avoid multiple endian conversion in pte helpers
In the same spirit as already done in pte query helpers,
this patch changes pte setting helpers to perform endian
conversions on the constants rather than on the pte value.

In the meantime, it changes pte_access_permitted() to use
pte helpers for the same reason.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Christophe Leroy
b2133bd7a5 powerpc/book3s/32: do not include pte-common.h
As done for book3s/64, add necessary flags/defines in
book3s/32/pgtable.h and do not include pte-common.h

It allows in the meantime to remove all related hash
definitions from pte-common.h and to also remove
_PAGE_EXEC default as _PAGE_EXEC is defined on all
platforms except book3s/32.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Christophe Leroy
f4805785f0 powerpc/mm: move __P and __S tables in the common pgtable.h
__P and __S flags are the same for all platform and should remain
as is in the future, so avoid duplication.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Christophe Leroy
093d7ca229 powerpc/mm: drop unused page flags
The following page flags in pte-common.h can be dropped:

_PAGE_ENDIAN is only used in mm/fsl_booke_mmu.c and is defined in
asm/nohash/32/pte-fsl-booke.h

_PAGE_4K_PFN is nowhere defined nor used

_PAGE_READ, _PAGE_WRITE and _PAGE_PTE are only defined and used
in book3s/64

The following page flags in book3s/64/pgtable.h can be dropped as
they are not used on this platform nor by common code.

_PAGE_NA, _PAGE_RO, _PAGE_USER and _PAGE_PSIZE

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Christophe Leroy
26973fa5ac powerpc/mm: use pte helpers in generic code
Get rid of platform specific _PAGE_XXXX in powerpc common code and
use helpers instead.

mm/dump_linuxpagetables.c will be handled separately

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Christophe Leroy
daba790242 powerpc/mm: add pte helpers to query and change pte flags
In order to avoid using generic _PAGE_XXX flags in powerpc
core functions, define helpers for all needed flags:
- pte_mkuser() and pte_mkprivileged() to set/unset and/or
unset/set _PAGE_USER and/or _PAGE_PRIVILEGED
- pte_hashpte() to check if _PAGE_HASHPTE is set.
- pte_ci() check if cache is inhibited (already existing on book3s/64)
- pte_exprotect() to protect against execution
- pte_exec() and pte_mkexec() to query and set page execution
- pte_mkpte() to set _PAGE_PTE flag.
- pte_hw_valid() to check _PAGE_PRESENT since pte_present does
something different on book3s/64.

On book3s/32 there is no exec protection, so pte_mkexec() and
pte_exprotect() are nops and pte_exec() returns always true.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Christophe Leroy
d81e6f8b7c powerpc/mm: don't use _PAGE_EXEC in book3s/32
book3s/32 doesn't define _PAGE_EXEC, so no need to use it.

All other platforms define _PAGE_EXEC so no need to check
it is not NUL when not book3s/32.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Christophe Leroy
c766ee7223 powerpc: handover page flags with a pgprot_t parameter
In order to avoid multiple conversions, handover directly a
pgprot_t to map_kernel_page() as already done for radix.

Do the same for __ioremap_caller() and __ioremap_at().

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Jan Kara
4628a64591 mm: Preserve _PAGE_DEVMAP across mprotect() calls
Currently _PAGE_DEVMAP bit is not preserved in mprotect(2) calls. As a
result we will see warnings such as:

BUG: Bad page map in process JobWrk0013  pte:800001803875ea25 pmd:7624381067
addr:00007f0930720000 vm_flags:280000f9 anon_vma:          (null) mapping:ffff97f2384056f0 index:0
file:457-000000fe00000030-00000009-000000ca-00000001_2001.fileblock fault:xfs_filemap_fault [xfs] mmap:xfs_file_mmap [xfs] readpage:          (null)
CPU: 3 PID: 15848 Comm: JobWrk0013 Tainted: G        W          4.12.14-2.g7573215-default #1 SLE12-SP4 (unreleased)
Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018
Call Trace:
 dump_stack+0x5a/0x75
 print_bad_pte+0x217/0x2c0
 ? enqueue_task_fair+0x76/0x9f0
 _vm_normal_page+0xe5/0x100
 zap_pte_range+0x148/0x740
 unmap_page_range+0x39a/0x4b0
 unmap_vmas+0x42/0x90
 unmap_region+0x99/0xf0
 ? vma_gap_callbacks_rotate+0x1a/0x20
 do_munmap+0x255/0x3a0
 vm_munmap+0x54/0x80
 SyS_munmap+0x1d/0x30
 do_syscall_64+0x74/0x150
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
...

when mprotect(2) gets used on DAX mappings. Also there is a wide variety
of other failures that can result from the missing _PAGE_DEVMAP flag
when the area gets used by get_user_pages() later.

Fix the problem by including _PAGE_DEVMAP in a set of flags that get
preserved by mprotect(2).

Fixes: 69660fd797 ("x86, mm: introduce _PAGE_DEVMAP")
Fixes: ebd3119793 ("powerpc/mm: Add devmap support for ppc64")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-10-09 11:44:58 -07:00
Suraj Jitindar Singh
e3b6b46615 KVM: PPC: Book3S HV: Implement H_TLB_INVALIDATE hcall
When running a nested (L2) guest the guest (L1) hypervisor will use
the H_TLB_INVALIDATE hcall when it needs to change the partition
scoped page tables or the partition table which it manages.  It will
use this hcall in the situations where it would use a partition-scoped
tlbie instruction if it were running in hypervisor mode.

The H_TLB_INVALIDATE hcall can invalidate different scopes:

Invalidate TLB for a given target address:
- This invalidates a single L2 -> L1 pte
- We need to invalidate any L2 -> L0 shadow_pgtable ptes which map the L2
  address space which is being invalidated. This is because a single
  L2 -> L1 pte may have been mapped with more than one pte in the
  L2 -> L0 page tables.

Invalidate the entire TLB for a given LPID or for all LPIDs:
- Invalidate the entire shadow_pgtable for a given nested guest, or
  for all nested guests.

Invalidate the PWC (page walk cache) for a given LPID or for all LPIDs:
- We don't cache the PWC, so nothing to do.

Invalidate the entire TLB, PWC and partition table for a given/all LPIDs:
- Here we re-read the partition table entry and remove the nested state
  for any nested guest for which the first doubleword of the partition
  table entry is now zero.

The H_TLB_INVALIDATE hcall takes as parameters the tlbie instruction
word (of which only the RIC, PRS and R fields are used), the rS value
(giving the lpid, where required) and the rB value (giving the IS, AP
and EPN values).

[paulus@ozlabs.org - adapted to having the partition table in guest
memory, added the H_TLB_INVALIDATE implementation, removed tlbie
instruction emulation, reworded the commit message.]

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 16:04:27 +11:00
Suraj Jitindar Singh
fd10be2573 KVM: PPC: Book3S HV: Handle page fault for a nested guest
Consider a normal (L1) guest running under the main hypervisor (L0),
and then a nested guest (L2) running under the L1 guest which is acting
as a nested hypervisor. L0 has page tables to map the address space for
L1 providing the translation from L1 real address -> L0 real address;

	L1
	|
	| (L1 -> L0)
	|
	----> L0

There are also page tables in L1 used to map the address space for L2
providing the translation from L2 real address -> L1 read address. Since
the hardware can only walk a single level of page table, we need to
maintain in L0 a "shadow_pgtable" for L2 which provides the translation
from L2 real address -> L0 real address. Which looks like;

	L2				L2
	|				|
	| (L2 -> L1)			|
	|				|
	----> L1			| (L2 -> L0)
	      |				|
	      | (L1 -> L0)		|
	      |				|
	      ----> L0			--------> L0

When a page fault occurs while running a nested (L2) guest we need to
insert a pte into this "shadow_pgtable" for the L2 -> L0 mapping. To
do this we need to:

1. Walk the pgtable in L1 memory to find the L2 -> L1 mapping, and
   provide a page fault to L1 if this mapping doesn't exist.
2. Use our L1 -> L0 pgtable to convert this L1 address to an L0 address,
   or try to insert a pte for that mapping if it doesn't exist.
3. Now we have a L2 -> L0 mapping, insert this into our shadow_pgtable

Once this mapping exists we can take rc faults when hardware is unable
to automatically set the reference and change bits in the pte. On these
we need to:

1. Check the rc bits on the L2 -> L1 pte match, and otherwise reflect
   the fault down to L1.
2. Set the rc bits in the L1 -> L0 pte which corresponds to the same
   host page.
3. Set the rc bits in the L2 -> L0 pte.

As we reuse a large number of functions in book3s_64_mmu_radix.c for
this we also needed to refactor a number of these functions to take
an lpid parameter so that the correct lpid is used for tlb invalidations.
The functionality however has remained the same.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 16:04:27 +11:00