Commit Graph

1240 Commits

Author SHA1 Message Date
Aneesh Kumar K.V
72176dd0ad powerpc/mm: Use a helper for finding pte bits mapping I/O area
Use a helper instead of open coding with constants. A later patch will
drop the WIMG bits and use PowerISA 3.0 defines.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:32 +10:00
Aneesh Kumar K.V
e58e87adc8 powerpc/mm: Update _PAGE_KERNEL_RO
PS3 had used a PPP bit hack to implement a read only mapping in the
kernel area. Since we are bolting the ioremap area, it used the pte
flags _PAGE_PRESENT | _PAGE_USER to get a PPP value of 0x3 there by
resulting in a read only mapping. This means the area can be accessed by
user space, but kernel will never return such an address to user space.

But we can do better by implementing a read only kernel mapping using
PPP bits 0b110.

This also allows us to do read only kernel mapping for radix in later
patches.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:30 +10:00
Aneesh Kumar K.V
96270b1fc2 powerpc/mm: Remove RPN_SHIFT and RPN_SIZE
PTE_RPN_SHIFT is actually page size dependent. Even though PowerISA 3.0
expects only the lower 12 bits to be zero, we will always find the pages
to be PAGE_SHIFT aligned. In case of hash config, this also allows us to
use the additional 3 bits to track pte specific information. We need
to make sure we use these bits only for hash specific pte flags.

For both 4K and 64K config, pte now can hold 57 bits address.

Inorder to keep things simpler, drop PTE_RPN_SHIFT and PTE_RPN_SIZE and
specify the 57 bit detail explicitly.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:29 +10:00
Aneesh Kumar K.V
ac29c64089 powerpc/mm: Replace _PAGE_USER with _PAGE_PRIVILEGED
_PAGE_PRIVILEGED means the page can be accessed only by the kernel. This
is done to keep pte bits similar to PowerISA 3.0 Radix PTE format. User
pages are now marked by clearing _PAGE_PRIVILEGED bit.

Previously we allowed the kernel to have a privileged page in the lower
address range (USER_REGION). With this patch such access is denied.

We also prevent a kernel access to a non-privileged page in higher
address range (ie, REGION_ID != 0).

Both the above access scenarios should never happen.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:26 +10:00
Michael Ellerman
7e1e63c5e9 powerpc/mm: Convert pte_user() to static inline
In a subsequent patch we want to add a second definition of pte_user().
Before we do that, make the signature clear, ie. it takes a pte_t and
returns bool.

We move it up inside the existing #ifndef __ASSEMBLY__ block, but
otherwise it's a straight conversion.

Convert the call in settlbcam(), which passes an unsigned long, to pass
a pte_t.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:24 +10:00
Aneesh Kumar K.V
73a1441a9b powerpc/mm/subpage: Clear RWX bit to indicate no access
Subpage protection used to depend on the _PAGE_USER bit to implement no
access mode. This patch switches that to use _PAGE_RWX. We clear Read,
Write and Execute access from the pte instead of clearing _PAGE_USER
now. This was done so that we can switch to _PAGE_PRIVILEGED in a later
patch.

subpage_protection() returns pte bits that need to be cleared. Instead
of updating the interface to handle no-access in a separate way, it
appears simpler to clear RWX acecss to indicate no access.

We still don't insert hash ptes for no access implied by !_PAGE_RWX.
Hence we should not get PROT_FAULT with change.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:23 +10:00
Aneesh Kumar K.V
c7d54842de powerpc/mm: Use _PAGE_READ to indicate Read access
This splits the _PAGE_RW bit into _PAGE_READ and _PAGE_WRITE. It also
removes the dependency on _PAGE_USER for implying read only. Few things
to note here is that, we have read implied with write and execute
permission. Hence we should always find _PAGE_READ set on hash pte
fault.

We still can't switch PROT_NONE to !(_PAGE_RWX). Auto numa depends on
marking a prot none pte _PAGE_WRITE. (For more details look at
b191f9b106 "mm: numa: preserve PTE write permissions across a NUMA
hinting fault")

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:21 +10:00
Aneesh Kumar K.V
5dc1ef858c powerpc/mm: Use big endian Linux page tables for book3s 64
Traditionally Power server machines have used the Hashed Page Table MMU
mode. In this mode Linux manages its own tree of nested page tables,
aka. "the Linux page tables", which are not used by the hardware
directly, and software loads translations into the hash page table for
use by the hardware.

Power ISA 3.0 defines a new MMU mode, known as Radix Tree Translation,
where the hardware can directly operate on the Linux page tables.
However the hardware requires that the page tables be in big endian
format.

To accommodate this, switch the pgtable types to __be64 and add
appropriate endian conversions.

Because we will be supporting a single kernel binary that boots using
either radix or hash mode, we always store the Linux page tables big
endian, even in hash mode where they are not actually used by the
hardware.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Fix sparse errors, flesh out change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:18 +10:00
Michael Ellerman
3910a7f485 powerpc/mm: Add pte_xchg() helper
We have five locations in 64-bit hash MMU code that do a cmpxchg() of a
PTE. Currently doing it inline OK, but in a future patch we will be
converting the PTEs to __be64 in some configs. In that case we will need
casts at every cmpxchg() site in order to keep sparse happy.

So move the logic into a helper, this is a reasonably nice cleanup on
its own.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:16 +10:00
Aneesh Kumar K.V
4bece39b50 powerpc/mm: Drop PTE_ATOMIC_UPDATES from pmd_hugepage_update()
pmd_hugepage_update() is inside #ifdef CONFIG_TRANSPARENT_HUGEPAGE. THP
can only be enabled if PPC_BOOK3S_64=y && PPC_64K_PAGES=y, aka. hash64.

On hash64 we always define PTE_ATOMIC_UPDATES to 1, meaning the #ifdef
in pmd_hugepage_update() is unnecessary, so drop it.

That is also the only use of PTE_ATOMIC_UPDATES in any of the hash code,
meaning we no longer need to #define it at all in the hash headers.

Note it's still #defined and used in the nohash code.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:15 +10:00
Daniel Axtens
7f92bc5694 powerpc: sparse: Include headers for __weak symbols
Sometimes when sparse warns about undefined symbols, it isn't
because they should have 'static' added, it's because they're
overriding __weak symbols defined elsewhere, and the header has
been missed.

Fix a few of them by adding appropriate headers.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-04-12 21:05:19 +10:00
Michael Ellerman
1f4c66e805 powerpc/mm: Remove long disabled SLB code
We have a bunch of SLB related code in the tree which is there to handle
dynamic VSIDs - but currently it's all disabled at compile time. The
comments say "Keep that around for when we re-implement dynamic VSIDs".

But that was over 10 years ago (commit 3c726f8dee ("[PATCH] ppc64:
support 64k pages")). The chance that it would still work unchanged is
minimal, and in the meantime it's confusing to folks browsing/grepping
the code. If we ever want to re-instate it, it's in the git history.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Balbir Singh <bsingharora@gmail.com>
2016-04-11 20:30:40 +10:00
Sebastian Siewior
08a5bb2921 powerpc/mm: Fixup preempt underflow with huge pages
hugepd_free() used __get_cpu_var() once. Nothing ensured that the code
accessing the variable did not migrate from one CPU to another and soon
this was noticed by Tiejun Chen in 94b09d7554 ("powerpc/hugetlb:
Replace __get_cpu_var with get_cpu_var"). So we had it fixed.

Christoph Lameter was doing his __get_cpu_var() replaces and forgot
PowerPC. Then he noticed this and sent his fixed up batch again which
got applied as 69111bac42 ("powerpc: Replace __get_cpu_var uses").

The careful reader will noticed one little detail: get_cpu_var() got
replaced with this_cpu_ptr(). So now we have a put_cpu_var() which does
a preempt_enable() and nothing that does preempt_disable() so we
underflow the preempt counter.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-29 12:08:07 +11:00
Linus Torvalds
d5e2d00898 powerpc updates for 4.6
Highlights:
  - Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras
  - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V
  - Add POWER9 cputable entry from Michael Neuling
  - FPU/Altivec/VSX save/restore optimisations from Cyril Bur
  - Add support for new ftrace ABI on ppc64le from Torsten Duwe
 
 Various cleanups & minor fixes from:
  - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril
    Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey,
    Sukadev Bhattiprolu, Suraj Jitindar Singh.
 
 General:
  - atomics: Allow architectures to define their own __atomic_op_* helpers from
    Boqun Feng
  - Implement atomic{, 64}_*_return_* variants and acquire/release/relaxed
    variants for (cmp)xchg from Boqun Feng
  - Add powernv_defconfig from Jeremy Kerr
  - Fix BUG_ON() reporting in real mode from Balbir Singh
  - Add xmon command to dump OPAL msglog from Andrew Donnellan
  - Add xmon command to dump process/task similar to ps(1) from Douglas Miller
  - Clean up memory hotplug failure paths from David Gibson
 
 pci/eeh:
  - Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei
    Yang.
  - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
  - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
  - PCI: Add pcibios_bus_add_device() weak function from Wei Yang
  - MAINTAINERS: Update EEH details and maintainership from Russell Currey
 
 cxl:
  - Support added to the CXL driver for running on both bare-metal and
    hypervisor systems, from Christophe Lombard and Frederic Barrat.
  - Ignore probes for virtual afu pci devices from Vaibhav Jain
 
 perf:
  - Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu
  - hv-24x7: Fix usage with chip events, display change in counter values,
    display domain indices in sysfs, eliminate domain suffix in event names,
    from Sukadev Bhattiprolu
 
 Freescale:
  - Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum
    optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and
    other dt bits, and minor fixes/cleanup."
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJW69OrAAoJEFHr6jzI4aWAe5EQAJw/hE6WBQc6a7Tj70AnXOqR
 qk/m5pZjuTwQxfBteIvHR1pE5eXdlvtAjcD254LVkFkAbIn19W/h2k0VX/nlee7P
 n/VRHRifjtGmukqHrPYJJ7ua9mNlY7pxh3leGSixBFASnSWqMxNNNziNQtSTcuCs
 TjHiw6NkZ/kzeunA4bAfE4yHVUZjmL74oiS9JbLyaVHqoW4fqWLlh26AKo2yYMZI
 qPicBBG4HBi3FGvoexnKxlJNdcV4HO7LzDjJmCSfUKYCJi+Pw19T5qmhso0q0qVz
 vHg/A8HNeG4Hn83pNVmLeQSAIQRZ3DvTtcLgbjPo+TVwm/hzrRRBWipTeOVbkLW8
 2bcOXT4t7LWUq15EAJ1LYgYZGzcLrfRfUeOcuQ1TWd3+PcfY9pE7FmizsxAAfaVe
 E9j9mpz4XnIqBtWkFHneTIHkQ5OWptyKuZJEaYH0nut4VsP0k8NarkseafGqBPu7
 5eG83gbiQbCVixfOgblV9eocJ29JcwpjPAY4CZSGJimShg909FV7WRgZgJkKWrbK
 dBRco8Jcp4VglGfo2qymv7Uj4KwQoypBREOhiKUvrAsVlDxPfx+bcskhjGu9xGDC
 xs/+nme0/lKa/wg5K4C3mQ1GAlkMWHI0ojhJjsyODbetup5UbkEu03wjAaTdO9dT
 Y6ptGm0rYAJluPNlziFj
 =qkAt
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "This was delayed a day or two by some build-breakage on old toolchains
  which we've now fixed.

  There's two PCI commits both acked by Bjorn.

  There's one commit to mm/hugepage.c which is (co)authored by Kirill.

  Highlights:
   - Restructure Linux PTE on Book3S/64 to Radix format from Paul
     Mackerras
   - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh
     Kumar K.V
   - Add POWER9 cputable entry from Michael Neuling
   - FPU/Altivec/VSX save/restore optimisations from Cyril Bur
   - Add support for new ftrace ABI on ppc64le from Torsten Duwe

  Various cleanups & minor fixes from:
   - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy,
     Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell
     Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh.

  General:
   - atomics: Allow architectures to define their own __atomic_op_*
     helpers from Boqun Feng
   - Implement atomic{, 64}_*_return_* variants and acquire/release/
     relaxed variants for (cmp)xchg from Boqun Feng
   - Add powernv_defconfig from Jeremy Kerr
   - Fix BUG_ON() reporting in real mode from Balbir Singh
   - Add xmon command to dump OPAL msglog from Andrew Donnellan
   - Add xmon command to dump process/task similar to ps(1) from Douglas
     Miller
   - Clean up memory hotplug failure paths from David Gibson

  pci/eeh:
   - Redesign SR-IOV on PowerNV to give absolute isolation between VFs
     from Wei Yang.
   - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
   - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
   - PCI: Add pcibios_bus_add_device() weak function from Wei Yang
   - MAINTAINERS: Update EEH details and maintainership from Russell
     Currey

  cxl:
   - Support added to the CXL driver for running on both bare-metal and
     hypervisor systems, from Christophe Lombard and Frederic Barrat.
   - Ignore probes for virtual afu pci devices from Vaibhav Jain

  perf:
   - Export Power8 generic and cache events to sysfs from Sukadev
     Bhattiprolu
   - hv-24x7: Fix usage with chip events, display change in counter
     values, display domain indices in sysfs, eliminate domain suffix in
     event names, from Sukadev Bhattiprolu

  Freescale:
   - Updates from Scott: "Highlights include 8xx optimizations, 32-bit
     checksum optimizations, 86xx consolidation, e5500/e6500 cpu
     hotplug, more fman and other dt bits, and minor fixes/cleanup"

* tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits)
  powerpc: Fix unrecoverable SLB miss during restore_math()
  powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers
  powerpc/rcpm: Fix build break when SMP=n
  powerpc/book3e-64: Use hardcoded mttmr opcode
  powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible
  powerpc/T104xRDB: add tdm riser card node to device tree
  powerpc32: PAGE_EXEC required for inittext
  powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree
  powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s)
  powerpc/86xx: Introduce and use common dtsi
  powerpc/86xx: Update device tree
  powerpc/86xx: Move dts files to fsl directory
  powerpc/86xx: Switch to kconfig fragments approach
  powerpc/86xx: Update defconfigs
  powerpc/86xx: Consolidate common platform code
  powerpc32: Remove one insn in mulhdu
  powerpc32: small optimisation in flush_icache_range()
  powerpc: Simplify test in __dma_sync()
  powerpc32: move xxxxx_dcache_range() functions inline
  powerpc32: Remove clear_pages() and define clear_page() inline
  ...
2016-03-19 15:38:41 -07:00
Joonsoo Kim
fe896d1878 mm: introduce page reference manipulation functions
The success of CMA allocation largely depends on the success of
migration and key factor of it is page reference count.  Until now, page
reference is manipulated by direct calling atomic functions so we cannot
follow up who and where manipulate it.  Then, it is hard to find actual
reason of CMA allocation failure.  CMA allocation should be guaranteed
to succeed so finding offending place is really important.

In this patch, call sites where page reference is manipulated are
converted to introduced wrapper function.  This is preparation step to
add tracepoint to each page reference manipulation function.  With this
facility, we can easily find reason of CMA allocation failure.  There is
no functional change in this patch.

In addition, this patch also converts reference read sites.  It will
help a second step that renames page._count to something else and
prevents later attempt to direct access to it (Suggested by Andrew).

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Joonsoo Kim
e7df0d88c4 powerpc: query dynamic DEBUG_PAGEALLOC setting
We can disable debug_pagealloc processing even if the code is compiled
with CONFIG_DEBUG_PAGEALLOC.  This patch changes the code to query
whether it is enabled or not in runtime.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Linus Torvalds
10dc374766 One of the largest releases for KVM... Hardly any generic improvement,
but lots of architecture-specific changes.
 
 * ARM:
 - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
 - PMU support for guests
 - 32bit world switch rewritten in C
 - various optimizations to the vgic save/restore code.
 
 * PPC:
 - enabled KVM-VFIO integration ("VFIO device")
 - optimizations to speed up IPIs between vcpus
 - in-kernel handling of IOMMU hypercalls
 - support for dynamic DMA windows (DDW).
 
 * s390:
 - provide the floating point registers via sync regs;
 - separated instruction vs. data accesses
 - dirty log improvements for huge guests
 - bugfixes and documentation improvements.
 
 * x86:
 - Hyper-V VMBus hypercall userspace exit
 - alternative implementation of lowest-priority interrupts using vector
 hashing (for better VT-d posted interrupt support)
 - fixed guest debugging with nested virtualizations
 - improved interrupt tracking in the in-kernel IOAPIC
 - generic infrastructure for tracking writes to guest memory---currently
 its only use is to speedup the legacy shadow paging (pre-EPT) case, but
 in the future it will be used for virtual GPUs as well
 - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQEcBAABAgAGBQJW5r3BAAoJEL/70l94x66D2pMH/jTSWWwdTUJMctrDjPVzKzG0
 yOzHW5vSLFoFlwEOY2VpslnXzn5TUVmCAfrdmFNmQcSw6hGb3K/xA/ZX/KLwWhyb
 oZpr123ycahga+3q/ht/dFUBCCyWeIVMdsLSFwpobEBzPL0pMgc9joLgdUC6UpWX
 tmN0LoCAeS7spC4TTiTTpw3gZ/L+aB0B6CXhOMjldb9q/2CsgaGyoVvKA199nk9o
 Ngu7ImDt7l/x1VJX4/6E/17VHuwqAdUrrnbqerB/2oJ5ixsZsHMGzxQ3sHCmvyJx
 WG5L00ubB1oAJAs9fBg58Y/MdiWX99XqFhdEfxq4foZEiQuCyxygVvq3JwZTxII=
 =OUZZ
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "One of the largest releases for KVM...  Hardly any generic
  changes, but lots of architecture-specific updates.

  ARM:
   - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
   - PMU support for guests
   - 32bit world switch rewritten in C
   - various optimizations to the vgic save/restore code.

  PPC:
   - enabled KVM-VFIO integration ("VFIO device")
   - optimizations to speed up IPIs between vcpus
   - in-kernel handling of IOMMU hypercalls
   - support for dynamic DMA windows (DDW).

  s390:
   - provide the floating point registers via sync regs;
   - separated instruction vs.  data accesses
   - dirty log improvements for huge guests
   - bugfixes and documentation improvements.

  x86:
   - Hyper-V VMBus hypercall userspace exit
   - alternative implementation of lowest-priority interrupts using
     vector hashing (for better VT-d posted interrupt support)
   - fixed guest debugging with nested virtualizations
   - improved interrupt tracking in the in-kernel IOAPIC
   - generic infrastructure for tracking writes to guest
     memory - currently its only use is to speedup the legacy shadow
     paging (pre-EPT) case, but in the future it will be used for
     virtual GPUs as well
   - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits)
  KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch
  KVM: x86: disable MPX if host did not enable MPX XSAVE features
  arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit
  arm64: KVM: vgic-v3: Reset LRs at boot time
  arm64: KVM: vgic-v3: Do not save an LR known to be empty
  arm64: KVM: vgic-v3: Save maintenance interrupt state only if required
  arm64: KVM: vgic-v3: Avoid accessing ICH registers
  KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit
  KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit
  KVM: arm/arm64: vgic-v2: Reset LRs at boot time
  KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty
  KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function
  KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required
  KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers
  KVM: s390: allocate only one DMA page per VM
  KVM: s390: enable STFLE interpretation only if enabled for the guest
  KVM: s390: wake up when the VCPU cpu timer expires
  KVM: s390: step the VCPU timer while in enabled wait
  KVM: s390: protect VCPU cpu timer with a seqcount
  KVM: s390: step VCPU cpu timer during kvm_run ioctl
  ...
2016-03-16 09:55:35 -07:00
Linus Torvalds
d37a14bb5f Merge branch 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull ram resource handling changes from Ingo Molnar:
 "Core kernel resource handling changes to support NVDIMM error
  injection.

  This tree introduces a new I/O resource type, IORESOURCE_SYSTEM_RAM,
  for System RAM while keeping the current IORESOURCE_MEM type bit set
  for all memory-mapped ranges (including System RAM) for backward
  compatibility.

  With this resource flag it no longer takes a strcmp() loop through the
  resource tree to find "System RAM" resources.

  The new resource type is then used to extend ACPI/APEI error injection
  facility to also support NVDIMM"

* 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ACPI/EINJ: Allow memory error injection to NVDIMM
  resource: Kill walk_iomem_res()
  x86/kexec: Remove walk_iomem_res() call with GART type
  x86, kexec, nvdimm: Use walk_iomem_res_desc() for iomem search
  resource: Add walk_iomem_res_desc()
  memremap: Change region_intersects() to take @flags and @desc
  arm/samsung: Change s3c_pm_run_res() to use System RAM type
  resource: Change walk_system_ram() to use System RAM type
  drivers: Initialize resource entry to zero
  xen, mm: Set IORESOURCE_SYSTEM_RAM to System RAM
  kexec: Set IORESOURCE_SYSTEM_RAM for System RAM
  arch: Set IORESOURCE_SYSTEM_RAM flag for System RAM
  ia64: Set System RAM type and descriptor
  x86/e820: Set System RAM type and descriptor
  resource: Add I/O resource descriptor
  resource: Handle resource flags properly
  resource: Add System RAM resource type
2016-03-14 15:15:51 -07:00
Christophe Leroy
060ef9d89d powerpc32: PAGE_EXEC required for inittext
PAGE_EXEC is required for inittext, otherwise CONFIG_DEBUG_PAGEALLOC
ends up with an Oops

[    0.000000] Inode-cache hash table entries: 8192 (order: 1, 32768 bytes)
[    0.000000] Sorting __ex_table...
[    0.000000] bootmem::free_all_bootmem_core nid=0 start=0 end=2000
[    0.000000] Unable to handle kernel paging request for instruction fetch
[    0.000000] Faulting instruction address: 0xc045b970
[    0.000000] Oops: Kernel access of bad area, sig: 11 [#1]
[    0.000000] PREEMPT DEBUG_PAGEALLOC CMPC885
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 3.18.25-local-dirty #1673
[    0.000000] task: c04d83d0 ti: c04f8000 task.ti: c04f8000
[    0.000000] NIP: c045b970 LR: c045b970 CTR: 0000000a
[    0.000000] REGS: c04f9ea0 TRAP: 0400   Not tainted  (3.18.25-local-dirty)
[    0.000000] MSR: 08001032 <ME,IR,DR,RI>  CR: 39955d35  XER: a000ff40
[    0.000000]
GPR00: c045b970 c04f9f50 c04d83d0 00000000 ffffffff c04dcdf4 00000048 c04f6b10
GPR08: c04f6ab0 00000001 c0563488 c04f6ab0 c04f8000 00000000 00000000 b6db6db7
GPR16: 00003474 00000180 00002000 c7fec000 00000000 000003ff 00000176 c0415014
GPR24: c0471018 c0414ee8 c05304e8 c03aeaac c0510000 c0471018 c0471010 00000000
[    0.000000] NIP [c045b970] free_all_bootmem+0x164/0x228
[    0.000000] LR [c045b970] free_all_bootmem+0x164/0x228
[    0.000000] Call Trace:
[    0.000000] [c04f9f50] [c045b970] free_all_bootmem+0x164/0x228 (unreliable)
[    0.000000] [c04f9fa0] [c0454044] mem_init+0x3c/0xd0
[    0.000000] [c04f9fb0] [c045080c] start_kernel+0x1f4/0x390
[    0.000000] [c04f9ff0] [c0002214] start_here+0x38/0x98
[    0.000000] Instruction dump:
[    0.000000] 2f150000 7f968840 72a90001 3ad60001 56b5f87e 419a0028 419e0024 41a20018
[    0.000000] 807cc20c 38800000 7c638214 4bffd2f5 <3a940001> 3a100024 4bffffc8 7e368b78
[    0.000000] ---[ end trace dc8fa200cb88537f ]---

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-11 20:04:32 -06:00
Christophe Leroy
8478d7f091 powerpc: Simplify test in __dma_sync()
This simplification helps the compiler. We now have only one test
instead of two, so it reduces the number of branches.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-11 17:20:12 -06:00
Christophe Leroy
766d45cbee powerpc/8xx: rewrite flush_instruction_cache() in C
On PPC8xx, flushing instruction cache is performed by writing
in register SPRN_IC_CST. This registers suffers CPU6 ERRATA.
The patch rewrites the fonction in C so that CPU6 ERRATA will
be handled transparently

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-11 17:20:11 -06:00
Christophe Leroy
a7761fe489 powerpc/8xx: rewrite set_context() in C
There is no real need to have set_context() in assembly.
Now that we have mtspr() handling CPU6 ERRATA directly, we
can rewrite set_context() in C language for easier maintenance.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-11 17:20:11 -06:00
Christophe Leroy
e974cd4be0 powerpc32: remove ioremap_base
ioremap_base is not initialised and is nowhere used so remove it

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-11 17:18:02 -06:00
Christophe Leroy
c562eb06d5 powerpc32: Remove useless/wrong MMU:setio progress message
Commit 7711684947 ("[POWERPC] Remove unused machine call outs")
removed the call to setup_io_mappings(), so remove the associated
progress line message

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-11 17:18:02 -06:00
Christophe Leroy
3084cdb7cd powerpc32: refactor x_mapped_by_bats() and x_mapped_by_tlbcam() together
x_mapped_by_bats() and x_mapped_by_tlbcam() serve the same kind of
purpose, and are never defined at the same time.
So rename them x_block_mapped() and define them in the relevant
places

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-11 17:18:02 -06:00
Christophe Leroy
516d91893b powerpc/8xx: move setup_initial_memory_limit() into 8xx_mmu.c
Now we have a 8xx specific .c file for that so put it in there
as other powerpc variants do

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-11 17:18:01 -06:00
Christophe Leroy
a372acfac5 powerpc/8xx: Map linear kernel RAM with 8M pages
On a live running system (VoIP gateway for Air Trafic Control), over
a 10 minutes period (with 277s idle), we get 87 millions DTLB misses
and approximatly 35 secondes are spent in DTLB handler.
This represents 5.8% of the overall time and even 10.8% of the
non-idle time.
Among those 87 millions DTLB misses, 15% are on user addresses and
85% are on kernel addresses. And within the kernel addresses, 93%
are on addresses from the linear address space and only 7% are on
addresses from the virtual address space.

MPC8xx has no BATs but it has 8Mb page size. This patch implements
mapping of kernel RAM using 8Mb pages, on the same model as what is
done on the 40x.

In 4k pages mode, each PGD entry maps a 4Mb area: we map every two
entries to the same 8Mb physical page. In each second entry, we add
4Mb to the page physical address to ease life of the FixupDAR
routine. This is just ignored by HW.

In 16k pages mode, each PGD entry maps a 64Mb area: each PGD entry
will point to the first page of the area. The DTLB handler adds
the 3 bits from EPN to map the correct page.

With this patch applied, we now get only 13 millions TLB misses
during the 10 minutes period. The idle time has increased to 313s
and the overall time spent in DTLB miss handler is 6.3s, which
represents 1% of the overall time and 2.2% of non-idle time.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-11 17:18:01 -06:00
Paolo Bonzini
ab92f30875 KVM/ARM updates for 4.6
- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
 - PMU support for guests
 - 32bit world switch rewritten in C
 - Various optimizations to the vgic save/restore code
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJW36xjAAoJECPQ0LrRPXpDGQkQAMDppzcTOixT3e8VPdHAX09a
 Z5PO0gyTMVV7Jyz5Ul3pedPJA2GSK9mxOCwqvIFbdxLAR6ZB00juO5FrTHkSdI91
 1XLPj4bKoMWcVvhL/g5A4Glp/pVMW1k/9Yq8zZAtYlsLRlqG5rLOutSadcqHcYaJ
 cTD/pFf7b2oPtkTPyoFml75KgHBT/8uvAvFDOWA66Id2z6T11+PsBT/6XnGDiwKg
 tpGTNzx3kPIKIzOAOHqVW6UBxFOeabebXLT8wUz3VwNn/UbG6gkumMNApMAyF2q1
 zU0nAh8+7Ek6Dr4OFWE6BfW6sgg/l7i1lA8XoAmqG7ZTrSptCc59fvaZJxPruG+Q
 dMsU6QgR77JJjbZTinf9a1jReZ/liZrx2gZXedVKdILrjmDSq0UnGcxjUOEDZOGy
 2/dbrlJhv+LhpcJtuPpxPCfoqbW5L0ynzmuYuXRdRz3lTHiOWIRx5gugrhO+wH4D
 4gvZhbw3XCiYfpYHYhl8A1EH5kanKgdXDocz9yIm7mZm89gngufF/HkeXS3ZU25T
 yThyBGulGjqN4FCdgf1HolkTfFjnfSx4qJovJ58eHga+HNLXRkTecZZcbFy2OOHv
 8Bx0PIlwj4RgSaRLWQUudAhdhKS2g22DKDDljxFwhkMPNghvqkYMJCRDKLu6GBXQ
 4YsLKM+TaShHFjSpx+ao
 =rpvb
 -----END PGP SIGNATURE-----

Merge tag 'kvm-arm-for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM updates for 4.6

- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
- PMU support for guests
- 32bit world switch rewritten in C
- Various optimizations to the vgic save/restore code

Conflicts:
	include/uapi/linux/kvm.h
2016-03-09 11:50:42 +01:00
Linus Torvalds
b8155fe1b2 powerpc fixes for 4.5 #4
- cxl: Fix PSL timebase synchronization detection from Frederic Barrat
  - Fix oops when destroying hw_breakpoint event from Ravi Bangoria
  - Avoid lbarx on e5500 from Scott Wood
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIbBAABAgAGBQJW21wIAAoJEFHr6jzI4aWAiTQP+PWe24xwWmC/9FWBhT5rmHbs
 CO82Wy2X3gjMsQoXGqe48ohfToJAWEt5yXS+H/PKpoTYJ/yFcih2ufRw55Y6xzHs
 M98c4Rt4mAbGwkmwWTBjSc1zP+ReWeMNwRE69j6N6Xl+fDqGg6tMKrcysh6wdDLB
 ZhLeHZbVEGhIlXuxMjGyPrMxSrvcEZMMVrxp8eTycC6+wBHB4w4WzOpFx87WM0fn
 3g1Q5WWzRjW2iCeWa6tJLwIIzEACrFs8nfJU08mJU1n33YYVbpu+2klG+5ppfGAL
 JiuKt9/ZoWSAMwNU7yEwFdgjtnOzywTnt6kAUWFdMKLV7DktJ+sf0ucZF9oBg87e
 ermsXt+Jy591NXgoif5gFMELWouC+Ti9pnqxdOTawYC8TKFm0OGExJFZQMGmzBw1
 9ZpO/2pl0bsuNZyClspuFyVRrNb1sxddisSyKlxW+0Vnz1P432fRZZSz2gHLvClG
 RjQ+nsKZYj6vH0wfA+eG9+/a5iYjbfBKRNSjrO1g8pbc3ELeG5C2kXDePKnkt8+J
 jpvTLHxaRp44wNPcizPrEthrdlKxE8uvTUosRuSMSJu74SK7t8+9kCvgDnHYne51
 f/2Ko7CzAV2SfdKB+nWI2oJxfYpPlxqORZkYGkQZIOD5uQ8pvJ4yCNzy43XqFHFE
 DyJOYeTxVQmfMT6jkrg=
 =ZcDj
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 - cxl: Fix PSL timebase synchronization detection from Frederic Barrat
 - Fix oops when destroying hw_breakpoint event from Ravi Bangoria
 - Avoid lbarx on e5500 from Scott Wood

* tag 'powerpc-4.5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/fsl-book3e: Avoid lbarx on e5500
  powerpc/hw_breakpoint: Fix oops when destroying hw_breakpoint event
  cxl: Fix PSL timebase synchronization detection
2016-03-06 11:08:06 -08:00
chenhui zhao
ebb9d30a6a powerpc/mm: any thread in one core can be the first to setup TLB1
On e6500, in the case of cpu hotplug, either thread in one core
may be the first thread initilzing the TLB1. The subsequent threads
must not setup it again.

The code is derived from the comment of Scott Wood.

Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-04 23:44:02 -06:00
Ingo Molnar
bc94b99636 Linux 4.5-rc6
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJW0yM6AAoJEHm+PkMAQRiGeUwIAJRTHFPJTFpJcJjeZEV4/EL1
 7Pl0WSHs/CWBkXIevAg2HgkECSQ9NI9FAUFvoGxCldDpFAnL1U2QV8+Ur2qhiXMG
 5v0jILJuiw57qT/NfhEudZolerlRoHILmB3JRTb+DUV4GHZuWpTkJfUSI9j5aTEl
 w83XUgtK4bKeIyFbHdWQk6xqfzfFBSuEITuSXreOMwkFfMmeScE0WXOPLBZWyhPa
 v0rARJLYgM+vmRAnJjnG8unH+SgnqiNcn2oOFpevKwmpVcOjcEmeuxh/HdeZf7HM
 /R8F86OwdmXsO+z8dQxfcucLg+I9YmKfFr8b6hopu1sRztss2+Uk6H1j2J7IFIg=
 =tvkh
 -----END PGP SIGNATURE-----

Merge tag 'v4.5-rc6' into core/resources, to resolve conflict

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-04 12:12:08 +01:00
Scott Wood
37c5e942bb powerpc/fsl-book3e: Avoid lbarx on e5500
lbarx/stbcx. are implemented on e6500, but not on e5500.
Likewise, SMT is on e6500, but not on e5500.

So, avoid executing an unimplemented instruction by only locking
when needed (i.e. in the presence of SMT).

Signed-off-by: Scott Wood <oss@buserror.net>
2016-03-03 23:43:05 -06:00
Aneesh Kumar K.V
c367a44133 powerpc/mm: add _PAGE_HASHPTE similar to 4K hash
We don't need to update linux page table entry with _PAGE_HASHPTE early
in hash pte fault. A parallel pte update will loop via _PAGE_BUSY
and look at _PAGE_HASHPTE for a required hpte flush only if
_PAGE_BUSY is cleared. That ensures a pte update will wait for a
parallel hpte insert to finish before looking at _PAGE_HASHPTE bit.

To avoid further confusion drop setting _PAGE_HASHPTE in cmpxchg in __hash_page_4K.

commit 41743a4e34 ("powerpc: Free a PTE bit on ppc64 with 64K pages")
did similar change for 64K config

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-03 21:18:29 +11:00
Aneesh Kumar K.V
e9a681478c powerp/mm: Update code comments
We are updating pte in those functions.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-03 21:18:29 +11:00
Kirill A. Shutemov
ff20c2e0ac mm: Some arch may want to use HPAGE_PMD related values as variables
With next generation power processor, we are having a new mmu model
[1] that require us to maintain a different linux page table format.

Inorder to support both current and future ppc64 systems with a single
kernel we need to make sure kernel can select between different page
table format at runtime. With the new MMU (radix MMU) added, we will
have two different pmd hugepage size 16MB for hash model and 2MB for
Radix model. Hence make HPAGE_PMD related values as a variable.

Actual conversion of HPAGE_PMD to a variable for ppc64 happens in a
followup patch.

[1] http://ibm.biz/power-isa3 (Needs registration).

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-03 21:18:29 +11:00
Aneesh Kumar K.V
368ced78e6 powerpc/mm: Switch book3s 64 with 64K page size to 4 level page table
This is needed so that we can support both hash and radix page table
using single kernel. Radix kernel uses a 4 level table.

We now use physical address in upper page table tree levels. Even though
they are aligned to their size, for the masked bits we use the
bit positions as per PowerISA 3.0.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-03 21:18:28 +11:00
David Gibson
5c3c7ede2b powerpc/mm: Split hash page table sizing heuristic into a helper
htab_get_table_size() either retrieve the size of the hash page table (HPT)
from the device tree - if the HPT size is determined by firmware - or
uses a heuristic to determine a good size based on RAM size if the kernel
is responsible for allocating the HPT.

To support a PAPR extension allowing resizing of the HPT, we're going to
want the memory size -> HPT size logic elsewhere, so split it out into a
helper function.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-02 09:06:16 +11:00
David Gibson
1dace6c665 powerpc/mm: Clean up memory hotplug failure paths
This makes a number of cleanups to handling of mapping failures during
memory hotplug on Power:

For errors creating the linear mapping for the hot-added region:
  * This is now reported with EFAULT which is more appropriate than the
    previous EINVAL (the failure is unlikely to be related to the
    function's parameters)
  * An error in this path now prints a warning message, rather than just
    silently failing to add the extra memory.
  * Previously a failure here could result in the region being partially
    mapped.  We now clean up any partial mapping before failing.

For errors creating the vmemmap for the hot-added region:
   * This is now reported with EFAULT instead of causing a BUG() - this
     could happen for external reason (e.g. full hash table) so it's better
     to handle this non-fatally
   * An error message is also printed, so the failure won't be silent
   * As above a failure could cause a partially mapped region, we now
     clean this up. [mpe: move htab_remove_mapping() out of #ifdef
     CONFIG_MEMORY_HOTPLUG to enable this]

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-01 22:04:18 +11:00
David Gibson
27828f98a0 powerpc/mm: Handle removing maybe-present bolted HPTEs
At the moment the hpte_removebolted callback in ppc_md returns void and
will BUG_ON() if the hpte it's asked to remove doesn't exist in the first
place.  This is awkward for the case of cleaning up a mapping which was
partially made before failing.

So, we add a return value to hpte_removebolted, and have it return ENOENT
in the case that the HPTE to remove didn't exist in the first place.

In the (sole) caller, we propagate errors in hpte_removebolted to its
caller to handle.  However, we handle ENOENT specially, continuing to
complete the unmapping over the specified range before returning the error
to the caller.

This means that htab_remove_mapping() will work sanely on a partially
present mapping, removing any HPTEs which are present, while also returning
ENOENT to its caller in case it's important there.

There are two callers of htab_remove_mapping():
   - In remove_section_mapping() we already WARN_ON() any error return,
     which is reasonable - in this case the mapping should be fully
     present
   - In vmemmap_remove_mapping() we BUG_ON() any error.  We change that to
     just a WARN_ON() in the case of ENOENT, since failing to remove a
     mapping that wasn't there in the first place probably shouldn't be
     fatal.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-01 22:04:18 +11:00
David Gibson
abd0a0e791 powerpc/mm: Clean up error handling for htab_remove_mapping
Currently, the only error that htab_remove_mapping() can report is -EINVAL,
if removal of bolted HPTEs isn't implemeted for this platform.  We make
a few clean ups to the handling of this:

 * EINVAL isn't really the right code - there's nothing wrong with the
   function's arguments - use ENODEV instead
 * We were also printing a warning message, but that's a decision better
   left up to the callers, so remove it
 * One caller is vmemmap_remove_mapping(), which will just BUG_ON() on
   error, making the warning message redundant, so no change is needed
   there.
 * The other caller is remove_section_mapping().  This is called in the
   memory hot remove path at a point after vmemmap_remove_mapping() so
   if hpte_removebolted isn't implemented, we'd expect to have already
   BUG()ed anyway.  Put a WARN_ON() here, in lieu of a printk() since this
   really shouldn't be happening.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-01 22:04:17 +11:00
Adam Buchbinder
446957ba51 powerpc: Fix misspellings in comments.
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-01 19:27:20 +11:00
Paul Mackerras
a9d4996df1 powerpc/mm/book3s-64: Move HPTE-related bits in PTE to upper end
This moves the _PAGE_HASHPTE, _PAGE_F_GIX and _PAGE_F_SECOND fields in
the Linux PTE on 64-bit Book 3S systems to the most significant byte.
Of the 5 bits, one is a software-use bit and the other four are
reserved bit positions in the PowerISA v3.0 radix PTE format.
Using these bits is OK because these bits are all to do with tracking
the HPTE(s) associated with the Linux PTE, and therefore won't be
needed in radix mode.  This frees up bit positions in the lower two
bytes.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-29 20:34:39 +11:00
Paul Mackerras
849f86a630 powerpc/mm/book3s-64: Move _PAGE_PRESENT to the most significant bit
This changes _PAGE_PRESENT for 64-bit Book 3S processors from 0x2 to
0x8000_0000_0000_0000, because that is where PowerISA v3.0 CPUs in
radix mode will expect to find it.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-29 20:34:39 +11:00
Paul Mackerras
c61a884312 powerpc/mm/book3s-64: Use physical addresses in upper page table tree levels
This changes the Linux page tables to store physical addresses
rather than kernel virtual addresses in the upper levels of the
tree (pgd, pud and pmd) for 64-bit Book 3S machines.

This also changes the hugepd pointers used to implement hugepages
when the base page size is 4k to store physical addresses rather than
virtual addresses (again just for 64-bit Book3S machines).

This frees up some high order bits, and will be needed with
PowerISA v3.0 machines which read the page table tree in hardware
in radix mode.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-29 20:34:34 +11:00
Daniel Cashman
5ef11c35ce mm: ASLR: use get_random_long()
Replace calls to get_random_int() followed by a cast to (unsigned long)
with calls to get_random_long().  Also address shifting bug which, in
case of x86 removed entropy mask for mmap_rnd_bits values > 31 bits.

Signed-off-by: Daniel Cashman <dcashman@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: David S. Miller <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nick Kralevich <nnk@google.com>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: Mark Salyzyn <salyzyn@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-27 10:28:52 -08:00
Paul Mackerras
f1a9ae034a powerpc/mm/book3s-64: Free up 7 high-order bits in the Linux PTE
This frees up bits 57-63 in the Linux PTE on 64-bit Book 3S machines.
In the 4k page case, this is done just by reducing the size of the
RPN field to 39 bits, giving 51-bit real addresses.  In the 64k page
case, we had 10 unused bits in the middle of the PTE, so this moves
the RPN field down 10 bits to make use of those unused bits.  This
means the RPN field is now 3 bits larger at 37 bits, giving 53-bit
real addresses in the normal case, or 49-bit real addresses for the
special 4k PFN case.

We are doing this in order to be able to move some other PTE bits
into the positions where PowerISA V3.0 processors will expect to
find them in radix-tree mode.  Ultimately we will be able to move
the RPN field to lower bit positions and make it larger.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-27 21:06:57 +11:00
Paul Mackerras
1ec3f93710 powerpc/mm/book3s-64: Clean up some obsolete or misleading comments
No code changes.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-27 21:06:57 +11:00
Aneesh Kumar K.V
9ab3ac233a powerpc/mm/hash: Clear the invalid slot information correctly
We can get a hash pte fault with 4k base page size and find the pte
already inserted with 64K base page size. In that case we need to clear
the existing slot information from the old pte. Fix this correctly

With THP, we also clear the slot information with respect to all
the 64K hash pte mapping that 16MB page. They are all invalid
now. This make sure we don't find the slot valid when we fault with
4k base page size. Finding the slot valid should not result in any wrong
behavior because we do check again in hash page table for the validity.
But we can avoid that check completely.

Fixes: a43c0eb836 ("powerpc/mm: Convert 4k hash insert to C")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-22 19:27:39 +11:00
Alexey Kardashevskiy
e9ab1a1caf powerpc: Make vmalloc_to_phys() public
This makes vmalloc_to_phys() public as there will be another user
(KVM in-kernel VFIO acceleration) for it soon. As this new user
can be compiled as a module, this exports the symbol.

As a little optimization, this changes the helper to call
vmalloc_to_pfn() instead of vmalloc_to_page() as the size of the
struct page may not be power-of-two aligned which will make gcc use
multiply instructions instead of shifts.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2016-02-16 13:44:26 +11:00
Aneesh Kumar K.V
c777e2a8b6 powerpc/mm: Fix Multi hit ERAT cause by recent THP update
With ppc64 we use the deposited pgtable_t to store the hash pte slot
information. We should not withdraw the deposited pgtable_t without
marking the pmd none. This ensure that low level hash fault handling
will skip this huge pte and we will handle them at upper levels.

Recent change to pmd splitting changed the above in order to handle the
race between pmd split and exit_mmap. The race is explained below.

Consider following race:

		CPU0				CPU1
shrink_page_list()
  add_to_swap()
    split_huge_page_to_list()
      __split_huge_pmd_locked()
        pmdp_huge_clear_flush_notify()
	// pmd_none() == true
					exit_mmap()
					  unmap_vmas()
					    zap_pmd_range()
					      // no action on pmd since pmd_none() == true
	pmd_populate()

As result the THP will not be freed. The leak is detected by check_mm():

	BUG: Bad rss-counter state mm:ffff880058d2e580 idx:1 val:512

The above required us to not mark pmd none during a pmd split.

The fix for ppc is to clear the huge pte of _PAGE_USER, so that low
level fault handling code skip this pte. At higher level we do take ptl
lock. That should serialze us against the pmd split. Once the lock is
acquired we do check the pmd again using pmd_same. That should always
return false for us and hence we should retry the access. We do the
pmd_same check in all case after taking plt with
THP (do_huge_pmd_wp_page, do_huge_pmd_numa_page and
huge_pmd_set_accessed)

Also make sure we wait for irq disable section in other cpus to finish
before flipping a huge pte entry with a regular pmd entry. Code paths
like find_linux_pte_or_hugepte depend on irq disable to get
a stable pte_t pointer. A parallel thp split need to make sure we
don't convert a pmd pte to a regular pmd entry without waiting for the
irq disable section to finish.

Fixes: eef1b3ba05 ("thp: implement split_huge_pmd()")
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-15 21:10:04 +11:00