Crash with ZFS between r296491 and r296548

[Alexander Motin]

On 09.03.16 06:10, Ed Maste wrote:
> On 9 March 2016 at 01:39, Ed Maste <emaste at freebsd.org> wrote:
>> On 8 March 2016 at 18:52, Jean-Sébastien Pédron
>> <jean-sebastien.pedron at dumbbell.fr> wrote:
>>> Hi!
>>>
>>> I use Root on ZFS and my laptop doesn't boot with a kernel from r296548
>>> and world from r296491 (so older than kernel). Ed hits a similar crash.
>>>
>>> Here are the dmesg and backtrace of zfs(8):
>>> https://gist.github.com/dumbbell/c9978ad4ac70214f0f47
>>>
>>> With a kernel and world from r296491, everything is ok.
>>>
>>> I didn't have the time to bisect the bad commit yet, so this is mostly a
>>> warning for other. Maybe someone will know what's wrong :)
>>
>> The error's coming from namespace_reload() in libzfs_util.c,
>> ioctl(hdl->libzfs_fd, ZFS_IOC_POOL_CONFIGS, &zc)
>>
>> I haven't had a chance to bisect yet either. There are 9 or so commits
>> between r296491 and r296548 -- I hope mav@ has some insight.
> 
> I still haven't been able to bisect, but in a local tree I've reverted
> recent ZFS changes and the issue is gone.
> 
> Reverted commits: r296510, r296512, r296514, r296516, r296519,
> r296521, r296523, r296528, r296530

Should be fixed by r296563.

Illumos assumes full sync between kernel and world, so they are quietly
breaking ABI as often as they want for any new feature.  One more set of
compat shim added helps for now.

-- 
Alexander Motin