From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MR5d0-0005Uo-IB for qemu-devel@nongnu.org; Wed, 15 Jul 2009 10:38:38 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MR5cv-0005U9-PJ for qemu-devel@nongnu.org; Wed, 15 Jul 2009 10:38:37 -0400 Received: from [199.232.76.173] (port=58452 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MR5cv-0005U4-K5 for qemu-devel@nongnu.org; Wed, 15 Jul 2009 10:38:33 -0400 Received: from mail-qy0-f174.google.com ([209.85.221.174]:45774) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MR5cv-0006TJ-A4 for qemu-devel@nongnu.org; Wed, 15 Jul 2009 10:38:33 -0400 Received: by qyk4 with SMTP id 4so2933950qyk.4 for ; Wed, 15 Jul 2009 07:38:32 -0700 (PDT) Message-ID: <4A5DE9E5.2080809@codemonkey.ws> Date: Wed, 15 Jul 2009 09:38:29 -0500 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] CPUID feature bits not saved with migration References: <4A5DD0B0.7070700@amd.com> In-Reply-To: <4A5DD0B0.7070700@amd.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: Andre Przywara Cc: qemu-devel@nongnu.org Andre Przywara wrote: > Hi, > > while testing the guest multi-core code, I realized that all of the > cpuid_* values (like cpuid_ext_features,...) from CPUX86State are not > dumped in the migration stream. Is this intentional behavior (to let > the user specify other bits in the target?) or has this just been > forgotten? > Does KVM call the SET_CPUID2 ioctl after or before migration? The cpuid bits are specified by the user. They aren't changable by the guest which is why they haven't been migrated. It's unclear what to do about -cpu host. If we did migrate cpuid values, then -cpu would effectively be ignored after an incoming migration. Regards, Anthony Liguori > Regards, > Andre. >