Re: [Qemu-devel] [PATCH v2 3/3] Add rate limiting of RTC_CHANGE, BALLOON_CHANGE & WATCHDOG events

[Daniel P. Berrange]

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.

Daniel
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