Comment 2 for bug 1842787

Apologies, it looks like I ran into two separate bugs, one with XFS, and one with BTRFS, that had the same symptom, initially making me to think this must be a QEMU issue.

Using blktrace, I was able to see within the VM, that the virtio block device wasn't getting the writes that were going into uninterruptible sleep.

So, this should be able to be closed. For some reason, virtio-blk seemed to trigger the bugs more rapidly, but at this point, I can't say there is anything at fault with it or virtio-scsi.

BTRFS issue was discussed and linked to here https://lore.kernel.org<email address hidden>/ and has been released. I've been able to run it for several days without a lockup, so it seems to have fixed the issue for me.

I just emailed the XFS list about the separate problems with it. No idea if it's an issue in more recent kernels than 5.1.15-5.1.16, which is what I was running at the time of the XFS errors. (Like the original report said, I was on 5.2.11 at that point.) See https://www.spinics.net/lists/linux-xfs/msg31927.html