From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [PATCH -v2] kvm: Emulate MOVBE Date: Sun, 14 Apr 2013 12:40:26 -0700 Message-ID: References: <20130410112942.07dfc167@slackpad> <20130410100845.GB17919@redhat.com> <20130410123901.46b65169@slackpad> <20130410121639.GE17919@redhat.com> <20130411001815.GA17544@pd.tnic> <20130411142818.GA17919@redhat.com> <20130411153733.GE27062@pd.tnic> <20130414074107.GD17919@redhat.com> <20130414173215.GD20547@pd.tnic> <4bbedfc0-67cb-48de-bfb5-2e0b0c42a9f6@email.android.com> <20130414190954.GE20547@pd.tnic> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Gleb Natapov , Andre Przywara , kvm@vger.kernel.org, =?ISO-8859-1?Q?J=F6rg_R=F6del?= , x86-ml To: Borislav Petkov Return-path: Received: from terminus.zytor.com ([198.137.202.10]:49812 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753474Ab3DNTlD (ORCPT ); Sun, 14 Apr 2013 15:41:03 -0400 In-Reply-To: <20130414190954.GE20547@pd.tnic> Sender: kvm-owner@vger.kernel.org List-ID: That is what I mean yes... Borislav Petkov wrote: >On Sun, Apr 14, 2013 at 11:36:29AM -0700, H. Peter Anvin wrote: >> Just to interject here... all this is about host kernel vs userspace, >> correct? I.e. nothing that affects the guest. I assume that the guest >> sees CPUID and that is what is supported. > >Actually, currently the guest sees MOVBE in CPUID set: > >max base function: 0x00000005 >CPUID.EAX=0x00000000 >EAX=0x00000005, EBX=0x68747541, ECX=0x444d4163, EDX=0x69746e65 >CPUID.EAX=0x00000001 >EAX=0x000106c2, EBX=0x01000800, ECX=0x80400201, EDX=0x0789fbff > ^ > |- bit 22 > >even though host (AMD) doesn't support it. > >And I'd say we want it that way because the guest should show it in >CPUID so that not only the guest kernel but also guest userspace >binaries built with MOVBE can be run. -- Sent from my mobile phone. Please excuse brevity and lack of formatting.