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From: Paolo Bonzini <pbonzini@redhat.com>
To: Eduardo Habkost <ehabkost@redhat.com>,
	Jidong Xiao <jidong.xiao@gmail.com>
Cc: qemu-devel@nongnu.org, KVM <kvm@vger.kernel.org>
Subject: Re: [Qemu-devel] [PATCH] Qemu: Fix eax for cpuid leaf 0x40000000
Date: Tue, 12 Aug 2014 21:12:00 +0200	[thread overview]
Message-ID: <53EA6700.2060603@redhat.com> (raw)
In-Reply-To: <20140812185552.GJ3011@thinpad.lan.raisama.net>

Il 12/08/2014 20:55, Eduardo Habkost ha scritto:
> This makes the CPUID data change under the guest's feet during
> live-migration.
> 
> Adding compat code to ensure older machine-types keep the old behavior
> is necessary, but in this specific case it is mostly harmless because
> 0x0 is documented as being equivalent to 0x40000001.
> 
> (But I don't know how guests are supposed to behave when they see
> CPUID[KVM_CPUID_SIGNATURE_NEXT].EAX==0.)

The only obvious thing to do would be to treat it as 0x40000101.

Paolo

  reply	other threads:[~2014-08-12 19:12 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-06-04  1:10 [Qemu-devel] [PATCH] Qemu: Fix eax for cpuid leaf 0x40000000 Jidong Xiao
2014-06-04  7:09 ` Paolo Bonzini
2014-06-04  7:17   ` Jidong Xiao
2014-06-04 19:08     ` Bandan Das
2014-06-04 19:47       ` Jidong Xiao
2014-06-04 21:26         ` Bandan Das
2014-08-12 18:55     ` Eduardo Habkost
2014-08-12 19:12       ` Paolo Bonzini [this message]
2014-08-12 19:29         ` Eduardo Habkost
2014-08-13 12:18           ` Paolo Bonzini

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