On Thu, Oct 17, 2024 at 01:29:07AM -0700, Carl E. Thompson wrote: > Unfortunately 6.10 and 6.11 aren't options for the normal use of my laptop. > But I was easily able to recover from backups so no harm done and I'm back on > 6.9. > > I do think problems with being able to switch between different kernel > versions are a pretty big deal, though. At least they are in my > workflows.
It absolutely is - that was a bug, and it was fixed, a year ago. But 6.9 hasn't been getting updates for some time, and 6.10 has been, so there's not really much I can do at this point. And you should be running a kernel that's still getting updates. > Would an approach similar to the one ZFS takes be better where the > filesystem's on-disk format is never upgraded automatically but > requires the admin to manually run an upgrade? At some point we'll likely be switching to that model. But for right now, while it's still marked experimental, it would be adding a lot of overhead to add conditionals to all the code for new features, so that's why I'm not doing it while we're still rapidly iterating - it wasn't realistically possible with the disk accounting rewrite. > Can tests be added to your test suite to make sure previous kernels > can still access and use filesystems after they've been upgraded by > newer kernels? I have those tests now. They're not run automatically yet, and they could use some improvement, but they're there. Again - bcachefs was only merged in 6.7, clearly marked experimental, and you're running 6.9; this kind of bug is exactly the sort of thing we try to shake out in the experimental phase. Also, a fsck would have sufficed, if you haven't ran that already.
