Re: [PATCH 2/3] work_on_cpu: Use our own workqueue.

[Ingo Molnar <mingo@elte.hu>]

* Andrew Morton <akpm@linux-foundation.org> wrote:

> On Wed, 4 Feb 2009 22:35:19 +0100
> Ingo Molnar <mingo@elte.hu> wrote:
> 
> > 
> > * Andrew Morton <akpm@linux-foundation.org> wrote:
> > 
> > > mm/pdflush.c:
> > > 
> > >   wtf what the heck is all that stuff and who added it?  weird.
> > > 
> > >   Leave it alone I guess.  Can admins manually move kernel threads to
> > >   other CPUs?
> > 
> > they can - and there's even tools that do that (there's some -rt tools where 
> > you can put kernel thread priorities into a config file).
> > 
> 
> Oh well, DontDoThatThen.
> 
> I expect that the same argument applies to most of the set_cpus_allowed()
> callsites - they're run by root-only code.  Sure, root can (with
> careful timing) move root's own thread onto the wrong CPU in the middle
> of microcode loading.  In which case root gets to own both pieces.
> 
> We only really need to worry about the places where non-root code can
> run set_cpus_allowed().  And then we only need to worry a little bit.
> 
> Yes?

Given the alternatives i suspect the best answer is a yes :)

	Ingo