Patch "thp: fix MADV_DONTNEED vs clear soft dirty race" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

thp: fix MADV_DONTNEED vs clear soft dirty race

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
thp-fix-madv_dontneed-vs-clear-soft-dirty-race.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: "Kirill A. Shutemov" <[email protected]>
Date: Thu, 13 Apr 2017 14:56:28 -0700
Subject: thp: fix MADV_DONTNEED vs clear soft dirty race

From: Kirill A. Shutemov <[email protected]>

commit 5b7abeae3af8c08c577e599dd0578b9e3ee6687b upstream.

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.

---
 fs/proc/task_mmu.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

@@ -803,7 +803,14 @@ 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 stable-queue which might be from [email protected] are

queue-4.4/thp-fix-madv_dontneed-vs-clear-soft-dirty-race.patch