Re: [patch] cgroups: disallow attaching kthreadd

[Tejun Heo <tj@kernel.org>]

On Wed, Apr 04, 2012 at 02:17:36PM -0700, David Rientjes wrote:
> On Wed, 4 Apr 2012, Mike Galbraith wrote:
> 
> > > I've never seen a nack from Peter on this, I only remember discussing 
> > > whether this needs to be isolated to only cpusets or whether it needs to 
> > > be a generic cgroup thing and I've always argued in favor of localizing it 
> > > to cpusets because that cgroup happens to care about cpu affinity where 
> > > others don't and this is why cgroups have ->can_attach() functions.  If a 
> > > cgroup were created to have nothing to do with cpu affinity (only for 
> > > collecting statistics for threads within it, for example), there's 
> > > absolutely no reason why we need to exclude kthreadd.
> > 
> > Well, he didn't actually say "NAK", but was against it, which means
> > pretty much the same thing as NAK to me.. we can call it a nak.
> > 
> 
> People are able to change their minds and after our discussion about 
> cgroups vs cpusets, I was under the impression we were at a common 
> understanding of the problem.
> 
> Cpusets are a cgroup.  It wouldn't make much sense to NACK a patch that 
> does this to cpusets if you're arguing in favor of doing it for all 
> cgroups.
> 
> Your changelog mentions only cpusets issues, not cgroup issues.
> 
> So please propose your cpusets version so that the issue can be fixed.  If 
> Peter wants to extend that to cgroups later, that's a discussion we can 
> have at that time.  However, the bug being addressed here is for cpusets 
> and is deserving of a patch now rather than later.  I'm concerned we're 
> just going to drop this again and it will live on.

I don't see much problem with the proposed solution and am gonna take
it unless there are pretty good reasons not to.

Thanks.

-- 
tejun