Il 13/06/2012 17:06, Daniel P. Berrange ha scritto: > On Wed, Jun 13, 2012 at 04:57:28PM +0200, Paolo Bonzini wrote: >> Il 13/06/2012 16:53, Daniel P. Berrange ha scritto: >>>>>>> I don't think SUSPEND can be used to DoS, since once the VM >>>>>>> is in the suspend state, a monitor command is required to wake >>>>>>> it up again before the guest OS can trigger a new suspend. >>>>> >>>>> Can't the guest OS awake itself? >>> I didn't think so. Even if it can, we can't rate limit SUSPEND >>> events in isolation, because they must be strictly ordered >>> wrt RESUME events. >> >> It can program the RTC to awake the OS, but only at 1 wakeup/second. > > Ah that hardware rate limit is good - we don't need todo separate > throttling with this event then.
Hmm, the ACPI PMTimer could be worse though. Perhaps we could write a kvm-unit-test and time how many wakeups we can do per second. Paolo
