Commit 3dfdb934 authored by Yan Zheng's avatar Yan Zheng Committed by Chris Mason
Browse files

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: default avatarYan Zheng <zheng.yan@oracle.com>
parent c6e30871

fs/btrfs/extent-tree.c

+3 −1
Original line number Diff line number Diff line
@@ -5952,9 +5952,11 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, 
	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);