From f9b000a7bb45c8cbd2d380f7716b8ef90f1ac68a Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Mon, 15 Jul 2013 12:41:42 -0400 Subject: [PATCH] Btrfs: fix lock leak when resuming snapshot deletion commit fec386ac1428f9c0e672df952cbca5cebd4e4e2f upstream. 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, Reported-by: Alex Lyakas Signed-off-by: Josef Bacik Signed-off-by: Ben Hutchings --- fs/btrfs/extent-tree.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 8d4d53dd3e16..78179a39c07d 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -6614,6 +6614,7 @@ void 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, @@ -6627,6 +6628,7 @@ void 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--; } -- 2.39.2