+ thp-fix-madv_dontneed-vs-madv_free-race.patch added to -mm tree

+ thp-fix-madv_dontneed-vs-madv_free-race.patch added to -mm tree

[akpm]

The patch titled
     Subject: thp: fix MADV_DONTNEED vs. MADV_FREE race
has been added to the -mm tree.  Its filename is
     thp-fix-madv_dontneed-vs-madv_free-race.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/thp-fix-madv_dontneed-vs-madv_free-race.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/thp-fix-madv_dontneed-vs-madv_free-race.patch

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------------------------------------------------------
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Subject: thp: fix MADV_DONTNEED vs. MADV_FREE race

Basically the same race as with numa balancing in change_huge_pmd(), but
a bit simpler to mitigate: we don't need to preserve dirty/young flags
here due to MADV_FREE functionality.

See "thp: fix MADV_DONTNEED vs. numa balancing race" for more details.

Link: http://lkml.kernel.org/r/20170302151034.27829-4-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/huge_memory.c |    2 --
 1 file changed, 2 deletions(-)

diff -puN mm/huge_memory.c~thp-fix-madv_dontneed-vs-madv_free-race mm/huge_memory.c
--- a/mm/huge_memory.c~thp-fix-madv_dontneed-vs-madv_free-race
+++ a/mm/huge_memory.c
@@ -1565,8 +1565,6 @@ bool madvise_free_huge_pmd(struct mmu_ga
 	unlock_page(page);
 
 	if (pmd_young(orig_pmd) || pmd_dirty(orig_pmd)) {
-		orig_pmd = pmdp_huge_get_and_clear_full(tlb->mm, addr, pmd,
-			tlb->fullmm);
 		orig_pmd = pmd_mkold(orig_pmd);
 		orig_pmd = pmd_mkclean(orig_pmd);
 
_

Patches currently in -mm which might be from kirill.shutemov@linux.intel.com are

rmap-fix-null-pointer-dereference-on-thp-munlocking.patch
thp-reduce-indentation-level-in-change_huge_pmd.patch
thp-fix-madv_dontneed-vs-numa-balancing-race.patch
thp-fix-madv_dontneed-vs-madv_free-race.patch
thp-fix-madv_dontneed-vs-clear-soft-dirty-race.patch