From c9a6820fc0da2603be3054ee7590eb9f350508a7 Mon Sep 17 00:00:00 2001
From: Wei Wang <wei.w.wang@intel.com>
Date: Tue, 19 Nov 2019 05:02:33 -0500
Subject: [PATCH] virtio_balloon: fix shrinker count
Git-commit: c9a6820fc0da2603be3054ee7590eb9f350508a7
References: git-fixes bnc#1151927 5.3.14
Patch-mainline: v5.4
Instead of multiplying by page order, virtio balloon divided by page
order. The result is that it can return 0 if there are a bit less
than MAX_ORDER - 1 pages in use, and then shrinker scan won't be called.
Cc: stable@vger.kernel.org
Fixes: 71994620bb25 ("virtio_balloon: replace oom notifier with shrinker")
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
drivers/virtio/virtio_balloon.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 51134f9a3ee7..e05679c478e2 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -826,7 +826,7 @@ static unsigned long virtio_balloon_shrinker_count(struct shrinker *shrinker,
unsigned long count;
count = vb->num_pages / VIRTIO_BALLOON_PAGES_PER_PAGE;
- count += vb->num_free_page_blocks >> VIRTIO_BALLOON_FREE_PAGE_ORDER;
+ count += vb->num_free_page_blocks << VIRTIO_BALLOON_FREE_PAGE_ORDER;
return count;
}
--
2.16.4