Re: 2.6.35 causes deadlock when snapshotting root lv

[Eric Sandeen <sandeen@sandeen.net>]

Eric Sandeen wrote:
> Phillip Susi wrote:
>> On 06/17/2010 12:27 PM, Mike Snitzer wrote:
>>>>> http://git.kernel.org/linus/18e9e5104fcd9a9
>>>>> http://git.kernel.org/linus/6b0310fbf087ad6
>>>> Yes, these do look suspicious.  I'll test reverting them tonight.
>>> OK, I'd suggest reverting the VFS change (18e9e5104fcd9a9) first.
>> Turns out it was 6b0310fbf087ad6 that did it.  CCing Eric Sandeen since
>> he wrote it.  Eric, this patch seems to cause a deadlock when taking an
>> lvm snapshot of the root lv.  Any idea why?
> 
> I'll look.  A sysrq-w when it hangs up would probably be enlightening...
> 
> -Eric

FWIW simple freeze/unfreeze works for me, and lvm snap on a non-root ext4
partition seems to as well.  I'm out for a few days and probably won't
get a root lv set up to test anytime soon.  If you can provide sysrq-w
output that probably will be a big help if it doesn't end up being obvious
by inspection.  :)

Thanks
-Eric