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

Paolo Bonzini
2014-11-25T17:38:04Z

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

Paolo

> + i++;
> + } while (ret == -ETIME && i < 10);
> +
> + if (ret == -ETIME) {
> + printk(KERN_ERR "%s: failed to reprogram timer\n",
> + __func__);
> + WARN_ON(1);
> + }
> + }