From: Qu Wenruo <wqu@xxxxxxxx> commit fd2b007eaec898564e269d1f478a2da0380ecf51 upstream. [BUG] For btrfs:qgroup_meta_reserve event, the trace event can output garbage: qgroup_meta_reserve: 9c7f6acc-b342-4037-bc47-7f6e4d2232d7: refroot=5(FS_TREE) type=DATA diff=2 The diff should always be alinged to sector size (4k), so there is definitely something wrong. [CAUSE] For the wrong @diff, it's caused by wrong parameter order. The correct parameters are: struct btrfs_root, s64 diff, int type. However the parameters used are: struct btrfs_root, int type, s64 diff. Fixes: 4ee0d8832c2e ("btrfs: qgroup: Update trace events for metadata reservation") CC: stable@xxxxxxxxxxxxxxx # 4.19+ Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx> Signed-off-by: Qu Wenruo <wqu@xxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/btrfs/qgroup.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -3617,7 +3617,7 @@ int __btrfs_qgroup_reserve_meta(struct b return 0; BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize)); - trace_qgroup_meta_reserve(root, type, (s64)num_bytes); + trace_qgroup_meta_reserve(root, (s64)num_bytes, type); ret = qgroup_reserve(root, num_bytes, enforce, type); if (ret < 0) return ret; @@ -3664,7 +3664,7 @@ void __btrfs_qgroup_free_meta(struct btr */ num_bytes = sub_root_meta_rsv(root, num_bytes, type); BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize)); - trace_qgroup_meta_reserve(root, type, -(s64)num_bytes); + trace_qgroup_meta_reserve(root, -(s64)num_bytes, type); btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid, num_bytes, type); }