Qu Wenruo wrote: >On 2018/12/28 ??????9:40, Stephen R. van den Berg wrote: >>> It's caused by qgroup, and a dead lock on btrfs_drop_snapshot(). >>> This is one of the easiest way to trigger an ABBA deadlock. >>> Please either disable qgroup or apply this patch to solve it: >>> https://patchwork.kernel.org/patch/10725371/ Ok, booting the system in v4.20 with this patch. I'll report back if it does not resolve the problem. -- Stephen.
