Re: [patch -rt 2/2] KVM: lapic: mark LAPIC timer handler as irqsafe

Marcelo Tosatti
2014-12-04T13:43:52Z

On Tue, Nov 25, 2014 at 06:38:04PM +0100, Paolo Bonzini wrote:
>
>
> On 25/11/2014 18:21, Marcelo Tosatti wrote:
> > +
> > + if (r == HRTIMER_RESTART) {
> > + do {
> > + ret = hrtimer_start_expires(data, HRTIMER_MODE_ABS);
> > + if (ret == -ETIME)
> > + hrtimer_add_expires_ns(&ktimer->timer,
> > + ktimer->period);
>
> Is it possible to just compute the time where the next interrupt
> happens?

Yes but there is no guarantee hrtimer_start_expires will not fail.

> I suspect the printk and WARN_ON below can be easily triggered
> by a guest.

I'll remove those, thanks.