From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NSrYb-0005fK-Ct for qemu-devel@nongnu.org; Thu, 07 Jan 2010 07:33:41 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NSrYW-0005Xv-BR for qemu-devel@nongnu.org; Thu, 07 Jan 2010 07:33:40 -0500 Received: from [199.232.76.173] (port=45456 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NSrYW-0005XT-0k for qemu-devel@nongnu.org; Thu, 07 Jan 2010 07:33:36 -0500 Received: from qw-out-1920.google.com ([74.125.92.146]:52903) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NSrYV-0007ly-OK for qemu-devel@nongnu.org; Thu, 07 Jan 2010 07:33:35 -0500 Received: by qw-out-1920.google.com with SMTP id 5so2996250qwc.4 for ; Thu, 07 Jan 2010 04:33:34 -0800 (PST) Message-ID: <4B45D497.40200@codemonkey.ws> Date: Thu, 07 Jan 2010 06:33:27 -0600 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] cpuid problem in upstream qemu with kvm References: <4B30EFDF.4060202@codemonkey.ws> <4B31F1BA.10005@redhat.com> <4B43D4E2.9050102@codemonkey.ws> <4B4402B1.1030605@redhat.com> <4B448F36.8030605@codemonkey.ws> <4B449467.4070606@redhat.com> <4B4494FC.1080907@codemonkey.ws> <4B449608.7040102@redhat.com> <4B4496E9.2030201@redhat.com> <20100106142231.GF2248@redhat.com> <4B449EE7.4050401@redhat.com> <4B44A2C6.4050504@redhat.com> <4B44A965.9040300@codemonkey.ws> <4B459550.6000202@redhat.com> <4B4598BC.4000206@redhat.com> <4B45A536.1070300@redhat.com> <4B45A851.5000401@redhat.com> <4B45AC18.8040003@redhat.com> <4B45C7EB.1010501@codemonkey.ws> <4B45C90C.1000507@redhat.com> <4B45CCCE.1010208@redhat.com> <4B45D170.7050000@redhat.com> In-Reply-To: <4B45D170.7050000@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: dlaor@redhat.com Cc: kvm-devel , Gleb Natapov , "Michael S. Tsirkin" , John Cooper , Alexander Graf , qemu-devel@nongnu.org, Avi Kivity On 01/07/2010 06:20 AM, Dor Laor wrote: > On 01/07/2010 02:00 PM, Avi Kivity wrote: >> On 01/07/2010 01:44 PM, Dor Laor wrote: >>>> So if you had a 2.6.18 kernel and a 2.6.33 kernel, it may be necessary >>>> to say: >>>> >>>> (2.6.33) qemu -cpu Nehalem,-syscall >>>> (2.6.18) qemu -cpu Nehalem >>> >>> >>> Or let qemu do it automatically for you. >> >> qemu on 2.6.33 doesn't know that you're running qemu on 2.6.18 on >> another node. >> > > We can live with it, either have qemu realize the kernel version out > of another existing feature or query uname. > > Alternatively, the matching libvirt package can be the one adding or > removing it in the right distribution. There's another option. Make cpuid information part of live migration protocol, and then support something like -cpu Xeon-3550. We would remember the exact cpuid mask we present to the guest and then we could validate that we can obtain the same mask on the destination. Regards, Anthony Liguori > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html