[PATCH v5] um: Enable preemption in UML

[Johannes Berg]

On Fri, 2023-09-22 at 11:55 +0100, Anton Ivanov wrote:
> On 22/09/2023 10:55, Johannes Berg wrote:
> > On Fri, 2023-09-22 at 11:51 +0200, Johannes Berg wrote:
> > > On Fri, 2023-09-22 at 10:19 +0100, Anton Ivanov wrote:
> > > > > So maybe that works - perhaps with a big comment?
> > > > Ack. Will add this to the patch and run it through its paces.
> > > > 
> > > We can also just get rid of it entirely:
> > > 
> > And then we can remove all the skas0 stuff, including init_thread_regs
> > and all.
> > 
> > Seems the cost would be basically that we now pagefault everything
> > that's used between fork() and exec()? But is that so much and so
> > important?
> 
> Needs testing :)

Yes. I sent a patch just now, works for me.

> Let's get the PREEMPT out of the door first.

Dunno. It has a conflict, but I think it's kind of a bugfix, the whole
mm creation copying from 'current' seems fishy when you consider
clone(CLONE_VM).

johannes