1. 02 Nov, 2017 1 commit
  2. 25 Oct, 2017 1 commit
  3. 21 Oct, 2017 1 commit
  4. 19 Oct, 2017 2 commits
  5. 18 Oct, 2017 5 commits
  6. 17 Oct, 2017 6 commits
  7. 16 Oct, 2017 2 commits
  8. 15 Oct, 2017 5 commits
  9. 14 Oct, 2017 12 commits
    • Linus Torvalds's avatar
      Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · e7a36a6e
      Linus Torvalds authored
      Pull x86 fixes from Ingo Molnar:
       "A landry list of fixes:
      
         - fix reboot breakage on some PCID-enabled system
      
         - fix crashes/hangs on some PCID-enabled systems
      
         - fix microcode loading on certain older CPUs
      
         - various unwinder fixes
      
         - extend an APIC quirk to more hardware systems and disable APIC
           related warning on virtualized systems
      
         - various Hyper-V fixes
      
         - a macro definition robustness fix
      
         - remove jprobes IRQ disabling
      
         - various mem-encryption fixes"
      
      * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        x86/microcode: Do the family check first
        x86/mm: Flush more aggressively in lazy TLB mode
        x86/apic: Update TSC_DEADLINE quirk with additional SKX stepping
        x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on hypervisors
        x86/mm: Disable various instrumentations of mm/mem_encrypt.c and mm/tlb.c
        x86/hyperv: Fix hypercalls with extended CPU ranges for TLB flushing
        x86/hyperv: Don't use percpu areas for pcpu_flush/pcpu_flush_ex structures
        x86/hyperv: Clear vCPU banks between calls to avoid flushing unneeded vCPUs
        x86/unwind: Disable unwinder warnings on 32-bit
        x86/unwind: Align stack pointer in unwinder dump
        x86/unwind: Use MSB for frame pointer encoding on 32-bit
        x86/unwind: Fix dereference of untrusted pointer
        x86/alternatives: Fix alt_max_short macro to really be a max()
        x86/mm/64: Fix reboot interaction with CR4.PCIDE
        kprobes/x86: Remove IRQ disabling from jprobe handlers
        kprobes/x86: Set up frame pointer in kprobe trampoline
      e7a36a6e
    • Linus Torvalds's avatar
      Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · a339b351
      Linus Torvalds authored
      Pull scheduler fixes from Ingo Molnar:
       "Three fixes that address an SMP balancing performance regression"
      
      * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        sched/core: Ensure load_balance() respects the active_mask
        sched/core: Address more wake_affine() regressions
        sched/core: Fix wake_affine() performance regression
      a339b351
    • Linus Torvalds's avatar
      Merge branch 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 7b764ced
      Linus Torvalds authored
      Pull RAS fixes from Ingo Molnar:
       "A boot parameter fix, plus a header export fix"
      
      * 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        x86/mce: Hide mca_cfg
        RAS/CEC: Use the right length for "cec_disable"
      7b764ced
    • Linus Torvalds's avatar
      Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 26c923ab
      Linus Torvalds authored
      Pull perf fixes from Ingo Molnar:
       "Some tooling fixes plus three kernel fixes: a memory leak fix, a
        statistics fix and a crash fix"
      
      * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        perf/x86/intel/uncore: Fix memory leaks on allocation failures
        perf/core: Fix cgroup time when scheduling descendants
        perf/core: Avoid freeing static PMU contexts when PMU is unregistered
        tools include uapi bpf.h: Sync kernel ABI header with tooling header
        perf pmu: Unbreak perf record for arm/arm64 with events with explicit PMU
        perf script: Add missing separator for "-F ip,brstack" (and brstackoff)
        perf callchain: Compare dsos (as well) for CCKEY_FUNCTION
      26c923ab
    • Linus Torvalds's avatar
      Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 60a6ca6c
      Linus Torvalds authored
      Pull locking fixes from Ingo Molnar:
       "Two lockdep fixes for bugs introduced by the cross-release dependency
        tracking feature - plus a commit that disables it because performance
        regressed in an absymal fashion on some systems"
      
      * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        locking/lockdep: Disable cross-release features for now
        locking/selftest: Avoid false BUG report
        locking/lockdep: Fix stacktrace mess
      60a6ca6c
    • Linus Torvalds's avatar
      Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 2b34218e
      Linus Torvalds authored
      Pull irq fixes from Ingo Molnar:
       "A CPU hotplug related fix, plus two related sanity checks"
      
      * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        genirq/cpuhotplug: Enforce affinity setting on startup of managed irqs
        genirq/cpuhotplug: Add sanity check for effective affinity mask
        genirq: Warn when effective affinity is not updated
      2b34218e
    • Linus Torvalds's avatar
      Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · a515d05e
      Linus Torvalds authored
      Pull objtool fix from Ingo Molnar:
       "A single objtool fix: avoid silently broken ORC debuginfo builds and
        error out instead"
      
      * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        objtool: Upgrade libelf-devel warning to error for CONFIG_ORC_UNWINDER
      a515d05e
    • Borislav Petkov's avatar
      x86/microcode: Do the family check first · 1f161f67
      Borislav Petkov authored
      On CPUs like AMD's Geode, for example, we shouldn't even try to load
      microcode because they do not support the modern microcode loading
      interface.
      
      However, we do the family check *after* the other checks whether the
      loader has been disabled on the command line or whether we're running in
      a guest.
      
      So move the family checks first in order to exit early if we're being
      loaded on an unsupported family.
      Reported-and-tested-by: default avatarSven Glodowski <glodi1@arcor.de>
      Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: <stable@vger.kernel.org> # 4.11..
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://bugzilla.suse.com/show_bug.cgi?id=1061396
      Link: http://lkml.kernel.org/r/20171012112316.977-1-bp@alien8.deSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      1f161f67
    • Ingo Molnar's avatar
      locking/lockdep: Disable cross-release features for now · b483cf3b
      Ingo Molnar authored
      Johan Hovold reported a big lockdep slowdown on his system, caused by lockdep:
      
      > I had noticed that the BeagleBone Black boot time appeared to have
      > increased significantly with 4.14 and yesterday I finally had time to
      > investigate it.
      >
      > Boot time (from "Linux version" to login prompt) had in fact doubled
      > since 4.13 where it took 17 seconds (with my current config) compared to
      > the 35 seconds I now see with 4.14-rc4.
      >
      > I quick bisect pointed to lockdep and specifically the following commit:
      >
      >	28a903f6 ("locking/lockdep: Handle non(or multi)-acquisition of a crosslock")
      
      Because the final v4.14 release is close, disable the cross-release lockdep
      features for now.
      Bisected-by: default avatarJohan Hovold <johan@kernel.org>
      Debugged-by: default avatarJohan Hovold <johan@kernel.org>
      Reported-by: default avatarJohan Hovold <johan@kernel.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Lindgren <tony@atomide.com>
      Cc: kernel-team@lge.com
      Cc: linux-arm-kernel@lists.infradead.org
      Cc: linux-mm@kvack.org
      Cc: linux-omap@vger.kernel.org
      Link: http://lkml.kernel.org/r/20171014072659.f2yr6mhm5ha3eou7@gmail.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      b483cf3b
    • Linus Torvalds's avatar
      Merge branch '4.14-fixes' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus · be1f16ba
      Linus Torvalds authored
      Pull MIPS fixes from Ralf Baechle:
       "More MIPS fixes for 4.14:
      
         - Loongson 1: Set the default number of RX and TX queues to
           accomodate for recent changes of stmmac driver.
      
         - BPF: Fix uninitialised target compiler error.
      
         - Fix cmpxchg on 32 bit signed ints for 64 bit kernels with
           !kernel_uses_llsc
      
         - Fix generic-board-config.sh for builds using O=
      
         - Remove pr_err() calls from fpu_emu() for a case which is not a
           kernel error"
      
      * '4.14-fixes' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
        MIPS: math-emu: Remove pr_err() calls from fpu_emu()
        MIPS: Fix generic-board-config.sh for builds using O=
        MIPS: Fix cmpxchg on 32b signed ints for 64b kernel with !kernel_uses_llsc
        MIPS: loongson1: set default number of rx and tx queues for stmmac
        MIPS: bpf: Fix uninitialised target compiler error
      be1f16ba
    • Andy Lutomirski's avatar
      x86/mm: Flush more aggressively in lazy TLB mode · b956575b
      Andy Lutomirski authored
      Since commit:
      
        94b1b03b ("x86/mm: Rework lazy TLB mode and TLB freshness tracking")
      
      x86's lazy TLB mode has been all the way lazy: when running a kernel thread
      (including the idle thread), the kernel keeps using the last user mm's
      page tables without attempting to maintain user TLB coherence at all.
      
      From a pure semantic perspective, this is fine -- kernel threads won't
      attempt to access user pages, so having stale TLB entries doesn't matter.
      
      Unfortunately, I forgot about a subtlety.  By skipping TLB flushes,
      we also allow any paging-structure caches that may exist on the CPU
      to become incoherent.  This means that we can have a
      paging-structure cache entry that references a freed page table, and
      the CPU is within its rights to do a speculative page walk starting
      at the freed page table.
      
      I can imagine this causing two different problems:
      
       - A speculative page walk starting from a bogus page table could read
         IO addresses.  I haven't seen any reports of this causing problems.
      
       - A speculative page walk that involves a bogus page table can install
         garbage in the TLB.  Such garbage would always be at a user VA, but
         some AMD CPUs have logic that triggers a machine check when it notices
         these bogus entries.  I've seen a couple reports of this.
      
      Boris further explains the failure mode:
      
      > It is actually more of an optimization which assumes that paging-structure
      > entries are in WB DRAM:
      >
      > "TlbCacheDis: cacheable memory disable. Read-write. 0=Enables
      > performance optimization that assumes PML4, PDP, PDE, and PTE entries
      > are in cacheable WB-DRAM; memory type checks may be bypassed, and
      > addresses outside of WB-DRAM may result in undefined behavior or NB
      > protocol errors. 1=Disables performance optimization and allows PML4,
      > PDP, PDE and PTE entries to be in any memory type. Operating systems
      > that maintain page tables in memory types other than WB- DRAM must set
      > TlbCacheDis to insure proper operation."
      >
      > The MCE generated is an NB protocol error to signal that
      >
      > "Link: A specific coherent-only packet from a CPU was issued to an
      > IO link. This may be caused by software which addresses page table
      > structures in a memory type other than cacheable WB-DRAM without
      > properly configuring MSRC001_0015[TlbCacheDis]. This may occur, for
      > example, when page table structure addresses are above top of memory. In
      > such cases, the NB will generate an MCE if it sees a mismatch between
      > the memory operation generated by the core and the link type."
      >
      > I'm assuming coherent-only packets don't go out on IO links, thus the
      > error.
      
      To fix this, reinstate TLB coherence in lazy mode.  With this patch
      applied, we do it in one of two ways:
      
       - If we have PCID, we simply switch back to init_mm's page tables
         when we enter a kernel thread -- this seems to be quite cheap
         except for the cost of serializing the CPU.
      
       - If we don't have PCID, then we set a flag and switch to init_mm
         the first time we would otherwise need to flush the TLB.
      
      The /sys/kernel/debug/x86/tlb_use_lazy_mode debug switch can be changed
      to override the default mode for benchmarking.
      
      In theory, we could optimize this better by only flushing the TLB in
      lazy CPUs when a page table is freed.  Doing that would require
      auditing the mm code to make sure that all page table freeing goes
      through tlb_remove_page() as well as reworking some data structures
      to implement the improved flush logic.
      Reported-by: default avatarMarkus Trippelsdorf <markus@trippelsdorf.de>
      Reported-by: default avatarAdam Borowski <kilobyte@angband.pl>
      Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
      Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Daniel Borkmann <daniel@iogearbox.net>
      Cc: Eric Biggers <ebiggers@google.com>
      Cc: Johannes Hirte <johannes.hirte@datenkhaos.de>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Nadav Amit <nadav.amit@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Roman Kagan <rkagan@virtuozzo.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Fixes: 94b1b03b ("x86/mm: Rework lazy TLB mode and TLB freshness tracking")
      Link: http://lkml.kernel.org/r/20171009170231.fkpraqokz6e4zeco@pd.tnicSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      b956575b
    • Linus Torvalds's avatar
      Merge tag 'drm-fixes-for-v4.14-rc5' of git://people.freedesktop.org/~airlied/linux · 9aa0d2dd
      Linus Torvalds authored
      Pull drm fixes from Dave Airlie:
       "Couple of the arm people seem to wake up so this has imx and msm
        fixes, along with a bunch of i915 stable bounds fixes and an amdgpu
        regression fix.
      
        All seems pretty okay for now"
      
      * tag 'drm-fixes-for-v4.14-rc5' of git://people.freedesktop.org/~airlied/linux:
        drm/msm: fix _NO_IMPLICIT fencing case
        drm/msm: fix error path cleanup
        drm/msm/mdp5: Remove extra pm_runtime_put call in mdp5_crtc_cursor_set()
        drm/msm/dsi: Use correct pm_runtime_put variant during host_init
        drm/msm: fix return value check in _msm_gem_kernel_new()
        drm/msm: use proper memory barriers for updating tail/head
        drm/msm/mdp5: add missing max size for 8x74 v1
        drm/amdgpu: fix placement flags in amdgpu_ttm_bind
        drm/i915/bios: parse DDI ports also for CHV for HDMI DDC pin and DP AUX channel
        gpu: ipu-v3: pre: implement workaround for ERR009624
        gpu: ipu-v3: prg: wait for double buffers to be filled on channel startup
        gpu: ipu-v3: Allow channel burst locking on i.MX6 only
        drm/i915: Read timings from the correct transcoder in intel_crtc_mode_get()
        drm/i915: Order two completing nop_submit_request
        drm/i915: Silence compiler warning for hsw_power_well_enable()
        drm/i915: Use crtc_state_is_legacy_gamma in intel_color_check
        drm/i915/edp: Increase the T12 delay quirk to 1300ms
        drm/i915/edp: Get the Panel Power Off timestamp after panel is off
        sync_file: Return consistent status in SYNC_IOC_FILE_INFO
        drm/atomic: Unref duplicated drm_atomic_state in drm_atomic_helper_resume()
      9aa0d2dd
  10. 13 Oct, 2017 5 commits
    • Dave Airlie's avatar
      Merge tag 'drm-intel-fixes-2017-10-11' of... · a480f308
      Dave Airlie authored
      Merge tag 'drm-intel-fixes-2017-10-11' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes
      
      drm/i915 fixes for 4.14-rc5:
      
      Three fixes for stable:
      
      - Use crtc_state_is_legacy_gamma in intel_color_check (Maarten)
      - Read timings from the correct transcoder (Ville).
      - Fix HDMI on BSW (Jani).
      
      Other fixes:
      
      - eDP fixes (Manasi)
      - Silence compiler warnings (Chris)
      - Order two completing nop_submit_request (Chris)
      
      * tag 'drm-intel-fixes-2017-10-11' of git://anongit.freedesktop.org/drm/drm-intel:
        drm/i915/bios: parse DDI ports also for CHV for HDMI DDC pin and DP AUX channel
        drm/i915: Read timings from the correct transcoder in intel_crtc_mode_get()
        drm/i915: Order two completing nop_submit_request
        drm/i915: Silence compiler warning for hsw_power_well_enable()
        drm/i915: Use crtc_state_is_legacy_gamma in intel_color_check
        drm/i915/edp: Increase the T12 delay quirk to 1300ms
        drm/i915/edp: Get the Panel Power Off timestamp after panel is off
      a480f308
    • Dave Airlie's avatar
      Merge branch 'msm-fixes-4.14-rc4' of git://people.freedesktop.org/~robclark/linux into drm-fixes · 7a5bea77
      Dave Airlie authored
      bunch of msm fixes
      
      * 'msm-fixes-4.14-rc4' of git://people.freedesktop.org/~robclark/linux:
        drm/msm: fix _NO_IMPLICIT fencing case
        drm/msm: fix error path cleanup
        drm/msm/mdp5: Remove extra pm_runtime_put call in mdp5_crtc_cursor_set()
        drm/msm/dsi: Use correct pm_runtime_put variant during host_init
        drm/msm: fix return value check in _msm_gem_kernel_new()
        drm/msm: use proper memory barriers for updating tail/head
        drm/msm/mdp5: add missing max size for 8x74 v1
      7a5bea77
    • Linus Torvalds's avatar
      Merge branch 'akpm' (patches from Andrew) · 06d97c58
      Linus Torvalds authored
      Merge misc fixes from Andrew Morton:
       "18 fixes"
      
      * emailed patches from Andrew Morton <akpm@linux-foundation.org>:
        mm, swap: use page-cluster as max window of VMA based swap readahead
        mm: page_vma_mapped: ensure pmd is loaded with READ_ONCE outside of lock
        kmemleak: clear stale pointers from task stacks
        fs/binfmt_misc.c: node could be NULL when evicting inode
        fs/mpage.c: fix mpage_writepage() for pages with buffers
        linux/kernel.h: add/correct kernel-doc notation
        tty: fall back to N_NULL if switching to N_TTY fails during hangup
        Revert "vmalloc: back off when the current task is killed"
        mm/cma.c: take __GFP_NOWARN into account in cma_alloc()
        scripts/kallsyms.c: ignore symbol type 'n'
        userfaultfd: selftest: exercise -EEXIST only in background transfer
        mm: only display online cpus of the numa node
        mm: remove unnecessary WARN_ONCE in page_vma_mapped_walk().
        mm/mempolicy: fix NUMA_INTERLEAVE_HIT counter
        include/linux/of.h: provide of_n_{addr,size}_cells wrappers for !CONFIG_OF
        mm/madvise.c: add description for MADV_WIPEONFORK and MADV_KEEPONFORK
        lib/Kconfig.debug: kernel hacking menu: runtime testing: keep tests together
        mm/migrate: fix indexing bug (off by one) and avoid out of bound access
      06d97c58
    • Huang Ying's avatar
      mm, swap: use page-cluster as max window of VMA based swap readahead · 61b63972
      Huang Ying authored
      When the VMA based swap readahead was introduced, a new knob
      
        /sys/kernel/mm/swap/vma_ra_max_order
      
      was added as the max window of VMA swap readahead.  This is to make it
      possible to use different max window for VMA based readahead and
      original physical readahead.  But Minchan Kim pointed out that this will
      cause a regression because setting page-cluster sysctl to zero cannot
      disable swap readahead with the change.
      
      To fix the regression, the page-cluster sysctl is used as the max window
      of both the VMA based swap readahead and original physical swap
      readahead.  If more fine grained control is needed in the future, more
      knobs can be added as the subordinate knobs of the page-cluster sysctl.
      
      The vma_ra_max_order knob is deleted.  Because the knob was introduced
      in v4.14-rc1, and this patch is targeting being merged before v4.14
      releasing, there should be no existing users of this newly added ABI.
      
      Link: http://lkml.kernel.org/r/20171011070847.16003-1-ying.huang@intel.com
      Fixes: ec560175 ("mm, swap: VMA based swap readahead")
      Signed-off-by: default avatar"Huang, Ying" <ying.huang@intel.com>
      Reported-by: default avatarMinchan Kim <minchan@kernel.org>
      Acked-by: default avatarMinchan Kim <minchan@kernel.org>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Shaohua Li <shli@kernel.org>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Fengguang Wu <fengguang.wu@intel.com>
      Cc: Tim Chen <tim.c.chen@intel.com>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      61b63972
    • Will Deacon's avatar
      mm: page_vma_mapped: ensure pmd is loaded with READ_ONCE outside of lock · a7b10095
      Will Deacon authored
      Loading the pmd without holding the pmd_lock exposes us to races with
      concurrent updaters of the page tables but, worse still, it also allows
      the compiler to cache the pmd value in a register and reuse it later on,
      even if we've performed a READ_ONCE in between and seen a more recent
      value.
      
      In the case of page_vma_mapped_walk, this leads to the following crash
      when the pmd loaded for the initial pmd_trans_huge check is all zeroes
      and a subsequent valid table entry is loaded by check_pmd.  We then
      proceed into map_pte, but the compiler re-uses the zero entry inside
      pte_offset_map, resulting in a junk pointer being installed in
      pvmw->pte:
      
        PC is at check_pte+0x20/0x170
        LR is at page_vma_mapped_walk+0x2e0/0x540
        [...]
        Process doio (pid: 2463, stack limit = 0xffff00000f2e8000)
        Call trace:
          check_pte+0x20/0x170
          page_vma_mapped_walk+0x2e0/0x540
          page_mkclean_one+0xac/0x278
          rmap_walk_file+0xf0/0x238
          rmap_walk+0x64/0xa0
          page_mkclean+0x90/0xa8
          clear_page_dirty_for_io+0x84/0x2a8
          mpage_submit_page+0x34/0x98
          mpage_process_page_bufs+0x164/0x170
          mpage_prepare_extent_to_map+0x134/0x2b8
          ext4_writepages+0x484/0xe30
          do_writepages+0x44/0xe8
          __filemap_fdatawrite_range+0xbc/0x110
          file_write_and_wait_range+0x48/0xd8
          ext4_sync_file+0x80/0x4b8
          vfs_fsync_range+0x64/0xc0
          SyS_msync+0x194/0x1e8
      
      This patch fixes the problem by ensuring that READ_ONCE is used before
      the initial checks on the pmd, and this value is subsequently used when
      checking whether or not the pmd is present.  pmd_check is removed and
      the pmd_present check is inlined directly.
      
      Link: http://lkml.kernel.org/r/1507222630-5839-1-git-send-email-will.deacon@arm.com
      Fixes: f27176cf ("mm: convert page_mkclean_one() to use page_vma_mapped_walk()")
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      Tested-by: default avatarYury Norov <ynorov@caviumnetworks.com>
      Tested-by: default avatarRichard Ruigrok <rruigrok@codeaurora.org>
      Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      a7b10095