ZFS panic on boot (head)

[Guido Falsi]

On 08/06/20 21:43, Guido Falsi via freebsd-fs wrote:
> On 08/06/20 20:20, Guido Falsi via freebsd-fs wrote:
>> Hi,
>>
>> On a laptop running head r361728, after a normal reboot I'm
>> experiencing an had panic every boot.
> 
> I meant ZFS panic here.
> 
> BTW I don't mean any accusation or demand here. I am aware this could be
> an hardware problem or whatever. I'm just curious, and would like to
> know if I can spare reinstalling the OS. I'd like to understand what is
> going on.
> 
> I also tried too import the pool using a live CD on a usb key. Recent
> snapshot downloaded from freebsd.org. Unluckily "zfs import" does not
> list the pool as expected, so it's not even identifying it as such.
> 

Interesting discover:

setting vfs.zfs.recover=1 in loader allows the machine to mount the FS
rw and boot successfully.

It still gives two errors:

Solaris: WARNING: zfs: allocating allocated segment(offset=433818959872
size=4096) of (offset=433818931200 size=32768)


Solaris: WARNING: zfs: allocating allocated segment(offset=433815740416
size=4096) of (offset=433815736320 size=8192)


Unluckily trying to reboot without vfs.zfs.recover=1 leads to the same
panic, so the underlying corruption is not fixed.

a zpool scrub shows no errors.

rebooting without the recover option still panics.

Is there a way to repair this now that I'm able to boot multiuser? Apart
from scrub is there some more diagnostic to force rebuilding the broken
metadata?

Since now this laptop is not reliable anymore IMHO, I'd reinstall it at
some pint, but if someone is interested in debug data that can be
extracted from it, and is willing to hep me extract it, I can avoid
reinstalling it for some days.

So, really, if anyone is interested let me know!

-- 
Guido Falsi <mad at madpilot.net>