Avi Kivity <avi@xxxxxxxxxx> writes: >> With some debug, the cause seems to be in pit_do_work(). With the >> following patch, NMI watchdog seems to be working correctly (if irq >> disabled for long time, NMI watchdog can detect it). >> >> Is the following patch right? > > This would cause IRQs to be delivered even if the PIT is masked, no? In here, mask means pit_mask_notifer()? If masked, ->pending doesn't prevent to fire it? I'm not sure. > Are you in fact using the PIT? Linux prefers the HPET, and in my > experience the -no-hpet option makes NMIs work. Yes, this is old kernel (2.6.9), and is not using HPET (CONFIG_HPET_TIMER=n), using IO-APIC as NMI source (PMU seems to be unsupported on kvm for now). Unfortunately, -no-hpet didn't change situation. irq_stat.apic_timer_irqs and nmi_count() are same while irq is disabled. -- OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
