Hi Beth I still found the emulated HPET would result in some boot failure. For example, on my 2.6.30, with HPET enabled, the kernel would fail check_timer(), especially in timer_irq_works(). The testing of timer_irq_works() is let 10 ticks pass(using mdelay()), and want to confirm the clock source with at least 5 ticks advanced in jiffies. I've checked that, on my machine, it would mostly get only 4 ticks when HPET enabled, then fail the test. On the other hand, if I using PIT, it would get more than 10 ticks(maybe understandable if some complementary ticks there). Of course, extend the ticks count/mdelay() time can work. I think it's a major issue of HPET. And it maybe just due to a too long userspace path for interrupt injection... If it's true, I think it's not easy to deal with it. -- regards Yang, Sheng -- 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