Btrfs: fix locking issue in btrfs_remove_block_group
We should hold the block_group_cache_lock while modifying the
block groups red-black tree. Thank you,
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index a4e36c3..3bed6a7 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5952,9 +5952,11 @@
path = btrfs_alloc_path();
BUG_ON(!path);
- btrfs_remove_free_space_cache(block_group);
+ spin_lock(&root->fs_info->block_group_cache_lock);
rb_erase(&block_group->cache_node,
&root->fs_info->block_group_cache_tree);
+ spin_unlock(&root->fs_info->block_group_cache_lock);
+ btrfs_remove_free_space_cache(block_group);
down_write(&block_group->space_info->groups_sem);
list_del(&block_group->list);
up_write(&block_group->space_info->groups_sem);
