Hi Christoph, A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found that reverting the following commit resolved this bug: 909657615d9b ("scsi: libsas: allow async aborts") The regression was introduced as of v4.12-rc1, and it still exists in 4.14 mainline. I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue, or would it be best to submit a revert request? Thanks, Joe [0] http://pad.lv/1726519