Re: [PATCH] protect migration/%d etc from sched_setaffinity

[Robert Love <rml@tech9.net>]

On Thu, 2003-07-31 at 15:46, Joe Korty wrote:

> Lock out users from changing the cpu affinity of those per-cpu system
> daemons which cannot survive such a change, such as migration/%d.
> 
> Passes basic handtest of sched_setaffinity(2) on various locked and
> unlocked processes on a i386, otherwise untested except by eyeball.
> 
> Except for one line in i386, no arch needed any changes to support
> this patch.

I have been wondering what to do about processor affinity and kernel
threads. I just concluded "only root can change it, and we can let root
stab herself if she really wants to."

But if this is really an issue, why not just do:

	ret = -EINVAL;
	if (!p->mm)
		goto out_unlock;

in sys_sched_setaffinity ?

	Robert Love