From 69c8d46f2d3f1e1ab63d5b2858f320cada5c76d8 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Tue, 21 Jan 2020 09:17:06 -0500 Subject: [PATCH] btrfs: free block groups after free'ing fs trees Sometimes when running generic/475 we would trip the WARN_ON(cache->reserved) check when free'ing the block groups on umount. This is because sometimes we don't commit the transaction because of IO errors and thus do not cleanup the tree logs until at umount time. These blocks are still reserved until they are cleaned up, but they aren't cleaned up until _after_ we do the free block groups work. Fix this by moving the free after free'ing the fs roots, that way all of the tree logs are cleaned up and we have a properly cleaned fs. A bunch of loops of generic/475 confirmed this fixes the problem. CC: stable@vger.kernel.org # 4.9+ Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/disk-io.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 5ce2801f83881..aea48d6ddc0cc 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -4030,11 +4030,18 @@ void __cold close_ctree(struct btrfs_fs_info *fs_info) invalidate_inode_pages2(fs_info->btree_inode->i_mapping); btrfs_stop_all_workers(fs_info); - btrfs_free_block_groups(fs_info); - clear_bit(BTRFS_FS_OPEN, &fs_info->flags); free_root_pointers(fs_info, true); + /* + * We must free the block groups after dropping the fs_roots as we could + * have had an IO error and have left over tree log blocks that aren't + * cleaned up until the fs roots are freed. This makes the block group + * accounting appear to be wrong because there's pending reserved bytes, + * so make sure we do the block group cleanup afterwards. + */ + btrfs_free_block_groups(fs_info); + iput(fs_info->btree_inode); #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY -- 2.39.5