Re: parent transid verify failed + level verify failed

[Martin Steigerwald <martin@lichtvoll.de>]

Martin Steigerwald - 19.11.23, 17:41:17 CET:
> / was not mountable anymore after booting into GRML. Made image with dd
> and restored from backup onto a newly created BTRFS.

I at least have a possible explanation.

Yesterday I experienced 6.7-almost-rc2 not hibernating correctly, but 
instead hanging with black screen. I rebooted into 6.6.1. Last thing I did 
was remove 6.7-almost-rc2 and hibernate.

In the morning I was greeted by GRUB command line prompt for a reason I do 
not understand yet either. I recovered from this with two GRML sessions. 
For that at least I unlocked LUKS and mounted / and /boot in GRML. If my 
memory is correct after I fixed booting up in these two GRML sessions, 
kernel 6.6.1 resumed from hibernation. That does make some session as in 
the GRML session I did not touch the swap volume. So I bet the hibernation 
image was not invalidated. However that would explain the corruption on / 
filesystem. Cause it was mounted in between and then the kernel resumed 
from a hibernation image with outdated in-memory data structures for 
BTRFS.

If my memory and analysis is correct this would easily explain the 
corruption on /. Still not sure what happened to /home. I think I did not 
touch it on attempting to repair GRUB. However I am not 100% sure about 
that.

Would be interesting to know whether diagnostic data would fit that 
explanation.

In case that is correct, then I think it would be good that in case I ever 
need to fix up GRUB again I also activate swap volume within GRML in the 
hope to invalidate the hibernation image. But I am not completely sure 
whether activating swap would be enough for that.

> /home also had errors. Did not take a chance. Scrubbed it, updated a
> backup with good old rsync, recreated filesystem and restored from
> updated backup.

Best,
-- 
Martin