From: Josef Bacik Date: Mon, 15 Jul 2013 16:41:42 +0000 (-0400) Subject: Btrfs: fix lock leak when resuming snapshot deletion X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=fec386ac1428f9c0e672df952cbca5cebd4e4e2f;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git Btrfs: fix lock leak when resuming snapshot deletion We aren't setting path->locks[level] when we resume a snapshot deletion which means we won't unlock the buffer when we free the path. This causes deadlocks if we happen to re-allocate the block before we've evicted the extent buffer from cache. Thanks, Cc: stable@vger.kernel.org Reported-by: Alex Lyakas Signed-off-by: Josef Bacik --- diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index a429704dd95f..e814b1312511 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -7523,6 +7523,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root, while (1) { btrfs_tree_lock(path->nodes[level]); btrfs_set_lock_blocking(path->nodes[level]); + path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING; ret = btrfs_lookup_extent_info(trans, root, path->nodes[level]->start, @@ -7538,6 +7539,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root, break; btrfs_tree_unlock(path->nodes[level]); + path->locks[level] = 0; WARN_ON(wc->refs[level] != 1); level--; }