[PATCH 028/222] ext4: init pagevec in ext4_da_block_invalidatepages

[Herton Ronaldo Krzesinski]

3.5.7.3 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Sandeen <sandeen at redhat.com>

commit 66bea92c69477a75a5d37b9bfed5773c92a3c4b4 upstream.

ext4_da_block_invalidatepages is missing a pagevec_init(),
which means that pvec->cold contains random garbage.

This affects whether the page goes to the front or
back of the LRU when ->cold makes it to
free_hot_cold_page()

Reviewed-by: Lukas Czerner <lczerner at redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino at redhat.com>
Signed-off-by: Eric Sandeen <sandeen at redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso at mit.edu>
[ herton: adjust context ]
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 fs/ext4/inode.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 9e9aed3..75f537f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1491,6 +1491,8 @@ static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd)
 
 	index = mpd->first_page;
 	end   = mpd->next_page - 1;
+
+	pagevec_init(&pvec, 0);
 	while (index <= end) {
 		nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
 		if (nr_pages == 0)
-- 
1.7.9.5