The patch titled
Subject: mm-thp-fix-smp-race-condition-between-thp-page-fault-and-madv_dontneed-fix
has been added to the -mm tree. Its filename is
mm-thp-fix-smp-race-condition-between-thp-page-fault-and-madv_dontneed-fix.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-thp-fix-smp-race-condition-between-thp-page-fault-and-madv_dontneed-fix.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-thp-fix-smp-race-condition-between-thp-page-fault-and-madv_dontneed-fix.patch
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------------------------------------------------------
From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Subject: mm-thp-fix-smp-race-condition-between-thp-page-fault-and-madv_dontneed-fix
tidy up comment grammar/layout
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory.c | 19 +++++++++----------
1 file changed, 9 insertions(+), 10 deletions(-)
diff -puN mm/memory.c~mm-thp-fix-smp-race-condition-between-thp-page-fault-and-madv_dontneed-fix mm/memory.c
--- a/mm/memory.c~mm-thp-fix-smp-race-condition-between-thp-page-fault-and-madv_dontneed-fix
+++ a/mm/memory.c
@@ -3405,16 +3405,15 @@ static int __handle_mm_fault(struct mm_s
unlikely(__pte_alloc(mm, vma, pmd, address)))
return VM_FAULT_OOM;
/*
- * If an huge pmd materialized from under us just retry later.
- * Use pmd_trans_unstable() instead of pmd_trans_huge() to
- * ensure the pmd didn't become pmd_trans_huge from under us
- * and then back to pmd_none, as result of MADV_DONTNEED
- * running immediately after a huge pmd fault of a different
- * thread of this mm, in turn leading to a misleading
- * pmd_trans_huge() retval. All we have to ensure is that it
- * is a regular pmd that we can walk with pte_offset_map() and
- * we can do that through an atomic read in C, which is what
- * pmd_trans_unstable() is provided for.
+ * If a huge pmd materialized under us just retry later. Use
+ * pmd_trans_unstable() instead of pmd_trans_huge() to ensure the pmd
+ * didn't become pmd_trans_huge under us and then back to pmd_none, as
+ * a result of MADV_DONTNEED running immediately after a huge pmd fault
+ * in a different thread of this mm, in turn leading to a misleading
+ * pmd_trans_huge() retval. All we have to ensure is that it is a
+ * regular pmd that we can walk with pte_offset_map() and we can do that
+ * through an atomic read in C, which is what pmd_trans_unstable()
+ * provides.
*/
if (unlikely(pmd_trans_unstable(pmd) || pmd_devmap(*pmd)))
return 0;
_
Patches currently in -mm which might be from akpm@xxxxxxxxxxxxxxxxxxxx are
i-need-old-gcc.patch
arch-alpha-kernel-systblss-remove-debug-check.patch
drivers-gpu-drm-i915-intel_spritec-fix-build.patch
drivers-gpu-drm-i915-intel_tvc-fix-build.patch
mm-thp-fix-smp-race-condition-between-thp-page-fault-and-madv_dontneed-fix.patch
arm-arch-arm-include-asm-pageh-needs-personalityh.patch
ocfs2-code-clean-up-for-direct-io-fix.patch
ocfs2-fix-ip_unaligned_aio-deadlock-with-dio-work-queue-fix.patch
ocfs2-dlm-move-lock-to-the-tail-of-grant-queue-while-doing-in-place-convert-fix.patch
mm.patch
mm-slab-clean-up-debug_pagealloc-processing-code-fix.patch
mm-slab-put-the-freelist-at-the-end-of-slab-page-fix.patch
slub-drop-lock-at-the-end-of-free_debug_processing-fix.patch
fs-mpagec-mpage_readpages-use-lru_to_page-helper.patch
mm-page_allocc-introduce-kernelcore=mirror-option-fix.patch
mm-page_allocc-rework-code-layout-in-memmap_init_zone.patch
mm-debug-pageallocc-split-out-page-poisoning-from-debug-page_alloc-checkpatch-fixes.patch
mm-page_poisonc-enable-page_poisoning-as-a-separate-option-fix.patch
mm-page_poisoningc-allow-for-zero-poisoning-checkpatch-fixes.patch
mm-madvise-update-comment-on-sys_madvise-fix.patch
mm-migrate-do-not-touch-page-mem_cgroup-of-live-pages-fix.patch
mm-simplify-lock_page_memcg-fix.patch
sched-add-schedule_timeout_idle.patch
mm-oom_reaper-report-success-failure-fix.patch
mm-compaction-speed-up-pageblock_pfn_to_page-when-zone-is-contiguous-fix.patch
proc-kpageflags-return-kpf_buddy-for-tail-buddy-pages-fix-fix.patch
mm-vmalloc-query-dynamic-debug_pagealloc-setting-fix.patch
mm-slub-query-dynamic-debug_pagealloc-setting-fix.patch
sound-query-dynamic-debug_pagealloc-setting-fix.patch
mm-config_nr_zones_extended-fix.patch
mm-add-a-new-vector-based-madvise-syscall-fix.patch
ksm-introduce-ksm_max_page_sharing-per-page-deduplication-limit-fix-2.patch
zram-export-the-number-of-available-comp-streams-fix.patch
mm-oom-rework-oom-detection-checkpatch-fixes.patch
mm-use-watermak-checks-for-__gfp_repeat-high-order-allocations-checkpatch-fixes.patch
btrfs-use-radix_tree_iter_retry-fix.patch
sparc-compat-provide-an-accurate-in_compat_syscall-implementation-fix.patch
sparc-compat-provide-an-accurate-in_compat_syscall-implementation-fix-fix.patch
rapidio-add-mport-char-device-driver-fix.patch
dma-rename-dma__writecombine-to-dma__wc-checkpatch-fixes.patch
kernel-add-kcov-code-coverage-fix.patch
kernel-add-kcov-code-coverage-fix-2.patch
linux-next-rejects.patch
drivers-net-wireless-intel-iwlwifi-dvm-calibc-fix-min-warning.patch
do_shared_fault-check-that-mmap_sem-is-held.patch
kernel-forkc-export-kernel_thread-to-modules.patch
slab-leaks3-default-y.patch
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