From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: Undocumented KVM_SET_LAPIC ioctl()
Date: Wed, 27 Apr 2011 11:26:52 +0300
Message-ID: <20110427082652.GK2265@redhat.com>
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Cc: Pekka Enberg <penberg@kernel.org>,
	KVM General <kvm@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
	Cyrill Gorcunov <gorcunov@gmail.com>
To: Avi Kivity <avi@redhat.com>
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On Wed, Apr 27, 2011 at 11:20:29AM +0300, Avi Kivity wrote:
> On 04/27/2011 10:53 AM, Pekka Enberg wrote:
> >On Wed, Apr 27, 2011 at 10:37 AM, Avi Kivity<avi@redhat.com>  wrote:
> >>  KVM_SET_GSI_ROUTING - manipulate the routes between irq lines and the IOAPIC
> >>  and PIC; also maintain virtual routes for message signalled interrupts (MSI)
> >
> >Is this mandatory to set up manually for lapic to work or does KVM set
> >these up automatically (like it does for most ioctls) to something
> >sane?
> 
> The defaults are all sane (including the APIC ID).
> 
But IIRC the only way to reset BSP lapic to its initial state is to call
KVM_SET_LAPIC with buffer filled with initial values. The same is true
for non-BSP lapics too if they are reset by machine reset (as opposite
to by INIT message).

--
			Gleb.