ZFS fatal double fault upon reboot after upgrade to 10.2

[Freek Dijkstra]

On 7-10-2015 0:59, Ben Woods wrote:

>> After an upgrade from FreeBSD 10.0 to 10.2, my system no longer boots
>> with an error:
>>
>>     Trying to mount root from zfs:zroot []...
>>     Fatal double fault:
> 
> I think you are experiencing a known issue with FreeBSD >= 10.1 on i386
> with multi-disk zfs configurations. Refer to the 2nd bullet point here:
> https://www.freebsd.org/releases/10.2R/errata.html#open-issues

Thank you very much for this pointer! I only read the announcements in
the release notes, not the errata...

> As described in /usr/src/UPDATING entry 20121223, rebuilding the kernel
> with options KSTACK_PAGES=4 has been observed to resolve the boot-time
> crash."

I sincerly hope this solves my issue.
I'll report back when I've compiled the kernel.

That's going to take a while... my (slow!) Atom CPU has been compiling
the kernel-toolchain for the last six hours, and still going....
Hopefully I can start compiling the kernel tonight... Perhaps it time to
learn how to compile a i386 kernel for my slow Soekris on my (faster)
amd64 server. :)

Thanks again for the pointers!
Freek