From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: Make QEmu HPET disabled by default for KVM?
Date: Thu, 11 Mar 2010 16:08:07 -0300
Message-ID: <20100311190807.GD17264@amt.cnet>
References: <201003111552.54293.sheng@linux.intel.com>
 <4B98A294.7010104@redhat.com>
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Cc: Sheng Yang <sheng@linux.intel.com>, kvm@vger.kernel.org,
	Gleb Natapov <gleb@redhat.com>
To: Avi Kivity <avi@redhat.com>
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On Thu, Mar 11, 2010 at 09:58:12AM +0200, Avi Kivity wrote:
> On 03/11/2010 09:52 AM, Sheng Yang wrote:
> >I think we have already suffered enough timer issues due to this(e.g. I can't
> >boot up well on 2.6.18 kernel)...
> 
> 2.6.18 as guest or as host?
> 
> >I have kept --no-hpet in my setup for
> >months...
> 
> Any details about the problems?  HPET is important to some guests.

As Gleb mentioned in the other thread, reinjection will introduce
another set of problems.

Ideally all this timer related problems should be fixed by correlating
timer interrupts and time source reads.

Since one already has to use special timer parameters (-rtc-td-hack,
-no-kvm-pit-reinjection), using -no-hpet for problematic Linux 
guests seems fine?