The patch titled
Subject: thp: fix MADV_DONTNEED vs clear soft dirty race
has been added to the -mm tree. Its filename is
thp-fix-madv_dontneed-vs-clear-soft-dirty-race.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/thp-fix-madv_dontneed-vs-clear-soft-dirty-race.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/thp-fix-madv_dontneed-vs-clear-soft-dirty-race.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Subject: thp: fix MADV_DONTNEED vs clear soft dirty race
Yet another instance of the same race.
Fix is identical to change_huge_pmd().
See "thp: fix MADV_DONTNEED vs. numa balancing race" for more details.
Link: http://lkml.kernel.org/r/20170302151034.27829-5-kirill.shutemov@xxxxxxxxxxxxxxx
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/proc/task_mmu.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff -puN fs/proc/task_mmu.c~thp-fix-madv_dontneed-vs-clear-soft-dirty-race fs/proc/task_mmu.c
--- a/fs/proc/task_mmu.c~thp-fix-madv_dontneed-vs-clear-soft-dirty-race
+++ a/fs/proc/task_mmu.c
@@ -906,7 +906,14 @@ static inline void clear_soft_dirty(stru
static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
unsigned long addr, pmd_t *pmdp)
{
- pmd_t pmd = pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp);
+ pmd_t pmd = *pmdp;
+
+ /* See comment in change_huge_pmd() */
+ pmdp_invalidate(vma, addr, pmdp);
+ if (pmd_dirty(*pmdp))
+ pmd = pmd_mkdirty(pmd);
+ if (pmd_young(*pmdp))
+ pmd = pmd_mkyoung(pmd);
pmd = pmd_wrprotect(pmd);
pmd = pmd_clear_soft_dirty(pmd);
_
Patches currently in -mm which might be from kirill.shutemov@xxxxxxxxxxxxxxx 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
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
