4.4-stable review patch. If anyone has any objections, please let me know.
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From: Liu Bo bo.li.liu@oracle.com
commit 02794222c4132ac003e7281fb71f4ec1645ffc87 upstream.
In a corrupted btrfs image, we can come across this BUG_ON and get an unreponsive system, but if we return errors instead, its caller can handle everything gracefully by aborting the current transaction.
Signed-off-by: Liu Bo bo.li.liu@oracle.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Ben Hutchings ben.hutchings@codethink.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/extent-tree.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -2342,7 +2342,13 @@ static int run_delayed_tree_ref(struct b ins.type = BTRFS_EXTENT_ITEM_KEY; }
- BUG_ON(node->ref_mod != 1); + if (node->ref_mod != 1) { + btrfs_err(root->fs_info, + "btree block(%llu) has %d references rather than 1: action %d ref_root %llu parent %llu", + node->bytenr, node->ref_mod, node->action, ref_root, + parent); + return -EIO; + } if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) { BUG_ON(!extent_op || !extent_op->update_flags); ret = alloc_reserved_tree_block(trans, root,