[PATCH] ext4: init pagevec in ext4_da_block_invalidatepages

[Eric Sandeen <sandeen@redhat.com>]

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()

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
---

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index b3c243b..f89c0e5 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1503,6 +1503,8 @@ 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)