zfs: panic on import

[Johannes Totz]

On 17/11/2011 00:21, Andriy Gapon wrote:
> on 17/11/2011 01:53 Johannes Totz said the following:
>> On 16/11/2011 18:40, Johannes Totz wrote:
>>> On 16/11/2011 17:50, Freddie Cash wrote:
>>>> On Wed, Nov 16, 2011 at 9:47 AM, Johannes Totz<jtotz at imperial.ac.uk>
>>>> wrote:
>>>>
>>>>> Does anybody have a very recent FreeBSD live cd/dvd image that I
>>>>> could try?
>>>>>
>>>>
>>>> The FreeBSD 9.0 install CD is a LiveCD. The first screen gives you the
>>>> option of starting the installer or dropping to a shell.
>>>>
>>>> 9.0-RC2 CDs are available on ftp://ftp.freebsd.org and should be
>>>> available
>>>> on most mirrors by now.
>>>>
>>>
>>> Ah thanks for the pointer, I always get lost navigating the ftp sever...
>>>
>>> But, same panic unfortunately (transcribbled):
>>>
>>> current process: txg_thread_enter
>>> panic: page fault
>>> ...
>>> #5 ... calltrap
>>> #6 ... zio_vdev_io_start
>>> #7 ... zio_execute
>>> #8 ... zio_ioctl
>>> #9 ... zio_flush
>>> #10 ... vdev_config_sync
>>> #11 ... spa_sync
>>> #12 ... txg_sync_thread
>>> #13 ... fork_exit
>>> #14 ... fork_trampoline
>>
>> This PR http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/155587 seems related. I
>> also offlined the file-vdev before the machine crashed. Now it panics on import.
>> And I don't get any dump either...
>
>
> Perhaps the following commit might help you
> http://svnweb.freebsd.org/base?view=revision&revision=226617

Looks like that patch fixed it!
Using a 9-stable r227727 I was able to import the pool, detach the 
file-vdev and reboot the machine normally.
I will update the PR.