[merged] virtio_balloon-fix-race-by-fill-and-leak.patch removed from -mm tree

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The patch titled
     Subject: virtio_balloon: fix race by fill and leak
has been removed from the -mm tree.  Its filename was
     virtio_balloon-fix-race-by-fill-and-leak.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Minchan Kim <minchan@xxxxxxxxxx>
Subject: virtio_balloon: fix race by fill and leak

During my compaction-related stuff, I encountered a bug with ballooning.

With repeated inflating and deflating cycle, guest memory( ie, cat
/proc/meminfo | grep MemTotal) is decreased and couldn't be recovered.

The reason is balloon_lock doesn't cover release_pages_balloon so struct
virtio_balloon fields could be overwritten by race of fill_balloon(e,g,
vb->*pfns could be critical).

This patch fixes it in my test.

Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
Acked-by: Rafael Aquini <aquini@xxxxxxxxxx>
Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Cc: Konstantin Khlebnikov <koct9i@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 drivers/virtio/virtio_balloon.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN drivers/virtio/virtio_balloon.c~virtio_balloon-fix-race-by-fill-and-leak drivers/virtio/virtio_balloon.c
--- a/drivers/virtio/virtio_balloon.c~virtio_balloon-fix-race-by-fill-and-leak
+++ a/drivers/virtio/virtio_balloon.c
@@ -209,8 +209,8 @@ static unsigned leak_balloon(struct virt
 	 */
 	if (vb->num_pfns != 0)
 		tell_host(vb, vb->deflate_vq);
-	mutex_unlock(&vb->balloon_lock);
 	release_pages_balloon(vb);
+	mutex_unlock(&vb->balloon_lock);
 	return num_freed_pages;
 }
 
_

Patches currently in -mm which might be from minchan@xxxxxxxxxx are

zram-pass-gfp-from-zcomp-frontend-to-backend.patch
mm-support-madvisemadv_free.patch
mm-support-madvisemadv_free-fix.patch
mm-support-madvisemadv_free-fix-2.patch
mm-define-madv_free-for-some-arches.patch
mm-free-swp_entry-in-madvise_free.patch
mm-move-lazily-freed-pages-to-inactive-list.patch
mm-mark-stable-page-dirty-in-ksm.patch
x86-add-pmd_-for-thp.patch
sparc-add-pmd_-for-thp.patch
powerpc-add-pmd_-for-thp.patch
arm-add-pmd_mkclean-for-thp.patch
arm64-add-pmd_mkclean-for-thp.patch
mm-dont-split-thp-page-when-syscall-is-called.patch

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