From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Me4Xu-0000bf-5n for qemu-devel@nongnu.org; Thu, 20 Aug 2009 06:07:02 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Me4Xo-0000WD-2q for qemu-devel@nongnu.org; Thu, 20 Aug 2009 06:07:00 -0400 Received: from [199.232.76.173] (port=52134 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Me4Xn-0000W6-RE for qemu-devel@nongnu.org; Thu, 20 Aug 2009 06:06:55 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47594) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1Me4Xn-0006UU-2z for qemu-devel@nongnu.org; Thu, 20 Aug 2009 06:06:55 -0400 Message-ID: <4A8D2037.4000002@redhat.com> Date: Thu, 20 Aug 2009 13:06:47 +0300 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 2/3] push CPUID level to 4 to allow Intel multicore decoding References: <1250689362-11067-1-git-send-email-andre.przywara@amd.com> <1250689362-11067-3-git-send-email-andre.przywara@amd.com> In-Reply-To: <1250689362-11067-3-git-send-email-andre.przywara@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 On 08/19/2009 04:42 PM, Andre Przywara wrote: > Intel CPUs store the number of cores in CPUID leaf 4. So push > the maxleaf value to 4 to allow the guests access to this leaf. > There's a slight compatibility risk here. If a guest has broken handling for cpuid level 4, then upgrading qemu would cause it to behave differently. I don't think that's an issue for this patch, just highlighting the need for a systematic treatment of backward compatibility. -- error compiling committee.c: too many arguments to function