On Tue, 24 May 2022, Sven M. Hallberg wrote: ... > >Description: > I have a 64 GB USB stick which holds a single softraid partition which > holds a CRYPTO volume which holds a single FFS partition. I had this > mounted with softdep and was running chromium with HOME set to the > mountpoint of the USB stick. It had a number of modern (TM) web apps > open, including Slack and Google Docs. Other processes on the system > included Firefox with a remote conferencing app open, but the > environment untouched. > I left the system unattended for about 30 minutes to find a kernel > panic upon my return. The attached screenshot appears to show it in > chrome filesystem activity, in softdep_deallocate_dependencies(). > I have used this setup previously without issue for several hours at a > time. The only thing notably different this time around may have been > the concurrent workload in the otherwise unrelated Firefox.
As your first image showed, there was an unrecoverable I/O error. I.e., your USB stick has at least one bad block. Time to switch to your backup USB stick and throw out this one. The reason OpenBSD paniced in this case instead of just failing the specific involved operation is that you were using softdeps: there are cases where softdeps can delay an operation to a point where the write out for other operations depend on it such that if the I/O for that first operation fails, the dependent operations cannot be undone and the failure propagated up safely. Rather than continue and keep buffering unsavable data after claiming that the operations succeeded when they haven't, the softdeps code will panic. You can stop using softdeps and maybe you'll be able to get some more use out of that USB stick, but I wouldn't trust it for anything important. Philip Guenther
