Btrfs: fix extent buffer reference for tree mod log roots
In get_old_root we grab a lock on the extent buffer before we obtain a
reference on that buffer. That order is changed now.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index ef68c33..f673990 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1279,6 +1279,7 @@
if (!eb)
return NULL;
+ extent_buffer_get(eb);
btrfs_tree_read_lock(eb);
if (old_root) {
btrfs_set_header_bytenr(eb, eb->start);
@@ -1291,7 +1292,6 @@
__tree_mod_log_rewind(eb, time_seq, tm);
else
WARN_ON(btrfs_header_level(eb) != 0);
- extent_buffer_get(eb);
WARN_ON(btrfs_header_nritems(eb) > BTRFS_NODEPTRS_PER_BLOCK(root));
return eb;
