Re: regression 4.4: deadlock in with cgroup percpu_rwsem

[Tejun Heo]

Hello,

On Tue, Jan 19, 2016 at 08:36:18PM +0100, Christian Borntraeger wrote:
> No, its not a task_struct. Activating some more debug information did indeed 
> revealed several other issues (overwritten redzones etc). Unfortunately I 
> only saw the broken things after the facts, so I do not know which code did that.
> When I disabled the cgroup controllers in libvirt I was no longer able to trigger
> the bugs. Still trying to narrow things down.

Hmmm... that's worrying.  CONFIG_DEBUG_PAGEALLOC sometimes can catch
these sort of bugs red-handed.  Might worth trying.

Thanks.

-- 
tejun