Hi Theodore, On Tue, Sep 15, 2020 at 12:45:19AM -0400, Theodore Y. Ts'o wrote: > On Thu, Sep 03, 2020 at 11:55:28PM -0400, Theodore Y. Ts'o wrote: > > Worse, right now, -rc1 and -rc2 is causing random crashes in my > > gce-xfstests framework. Sometimes it happens before we've run even a > > single xfstests; sometimes it happens after we have successfully > > completed all of the tests, and we're doing a shutdown of the VM under > > test. Other times it happens in the middle of a test run. Given that > > I'm seeing this at -rc1, which is before my late ext4 pull request to > > Linus, it's probably not an ext4 related bug. But it also means that > > I'm partially blind in terms of my kernel testing at the moment. So I > > can't even tell Linus that I've run lots of tests and I'm 100% > > confident your one-line change is 100% safe. > > I was finally able to bisect it down to the commit: > > 37f4a24c2469: blk-mq: centralise related handling into blk_mq_get_driver_tag 37f4a24c2469 has been reverted in: 4e2f62e566b5 Revert "blk-mq: put driver tag when this request is completed" And later the patch is committed as the following after being fixed: 568f27006577 blk-mq: centralise related handling into blk_mq_get_driver_tag So can you reproduce the issue by running kernel of commit 568f27006577? If yes, can the issue be fixed by reverting 568f27006577? > > (See below for [1] Bisect log.) > > The previous commit allows the tests to run to completion. With > commit 37f4a24c2469 and later all 11 test scenarios (4k blocks, 1k > blocks, ext3 compat, ext4 w/ fscrypt, nojournal mode, data=journal, > bigalloc, etc.) the VM will get stuck. Can you share the exact mount command line for setup the environment? and the exact xfstest item? Thanks, Ming