diff options
| author | Liu Bo <bo.li.liu@oracle.com> | 2016-11-30 16:11:04 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-08-06 18:59:47 -0700 |
| commit | 78418b86733462c913aea82e081594b1005751ba (patch) | |
| tree | 12e70340970331a0cc5ddef2f0f5359de3f7554f /fs | |
| parent | 92d6a813b03a576dd821667b6566a1ddf7617137 (diff) | |
Btrfs: use down_read_nested to make lockdep silent
[ Upstream commit e321f8a801d7b4c40da8005257b05b9c2b51b072 ]
If @block_group is not @used_bg, it'll try to get @used_bg's lock without
droping @block_group 's lock and lockdep has throwed a scary deadlock warning
about it.
Fix it by using down_read_nested.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/extent-tree.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index e46e7fbe1b34..14a37ff0b9e3 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -7401,7 +7401,8 @@ btrfs_lock_cluster(struct btrfs_block_group_cache *block_group, spin_unlock(&cluster->refill_lock); - down_read(&used_bg->data_rwsem); + /* We should only have one-level nested. */ + down_read_nested(&used_bg->data_rwsem, SINGLE_DEPTH_NESTING); spin_lock(&cluster->refill_lock); if (used_bg == cluster->block_group) |