| Message ID | 112f5da071c0d3446fedf7c7828c78ae586e11fb.1438869404.git.zhaolei@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 54114b4..5f745ea 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1159,8 +1159,10 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) { ret = btrfs_reloc_cow_block(trans, root, buf, cow); - if (ret) + if (ret) { + btrfs_abort_transaction(trans, root, ret); return ret; + } } if (buf == root->node) {
When btrfs_reloc_cow_block() failed in __btrfs_cow_block(), current code just return a err-value to caller, but leave new_created extent buffer exist and locked. Then subsequent code (in relocate) try to lock above eb again, and caused deadlock without any dmesg. (eb lock use wait_event(), so no lockdep message) It is hard to do recover work in __btrfs_cow_block() at this error point, but we can abort transaction to avoid deadlock and operate on unstable state.a It also helps developer to find wrong place quickly. (better than a frozen fs without any dmesg before patch) Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> --- fs/btrfs/ctree.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)