From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexander Graf <agraf@suse.de>
Subject: Re: [RFC 0/2] GET_EMULATED_CPUID support with "allow-emulation" option
Date: Thu, 05 Jun 2014 18:45:16 +0200
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Cc: Borislav Petkov <bp@alien8.de>,
	"Gabriel L. Somlo" <gsomlo@gmail.com>, kvm@vger.kernel.org,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Michael Mueller <mimu@linux.vnet.ibm.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	"Jason J. Herne" <jjherne@linux.vnet.ibm.com>,
	=?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= <afaerber@suse.de>
To: Paolo Bonzini <pbonzini@redhat.com>,
	Eduardo Habkost <ehabkost@redhat.com>, qemu-devel@nongnu.org
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On 05.06.14 18:44, Paolo Bonzini wrote:
> Il 05/06/2014 18:40, Alexander Graf ha scritto:
>>
>>
>>   kvm_set_cpuid(cpuid);
>>
>> but enabling all experimental features inside KVM just because we want
>> one or two of them is very counter-intuitive. Imagine we'd introduce
>> emulation support for AVX. Suddenly allow-emulation (which I'd need for
>> Mac OS X 10.5) would enable AVX as well which I really don't want 
>> enabled.
>
> Only if you were using "-cpu somethingThatHasAVX", though, no?

Yes. The same argument goes the other way around. I want to use AVX 
emulation, do "allow-emulation" and suddenly I get MONITOR/MWAIT emulation.


Alex