From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MJ2qR-0000Mk-J3 for qemu-devel@nongnu.org; Tue, 23 Jun 2009 06:03:15 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MJ2qM-0000KE-RF for qemu-devel@nongnu.org; Tue, 23 Jun 2009 06:03:15 -0400 Received: from [199.232.76.173] (port=51610 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MJ2qM-0000K9-LY for qemu-devel@nongnu.org; Tue, 23 Jun 2009 06:03:10 -0400 Received: from mx2.redhat.com ([66.187.237.31]:41788) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MJ2qM-0008Uy-1n for qemu-devel@nongnu.org; Tue, 23 Jun 2009 06:03:10 -0400 Message-ID: <4A40A891.4010606@redhat.com> Date: Tue, 23 Jun 2009 13:04:01 +0300 From: Avi Kivity MIME-Version: 1.0 References: <1245707277-769-1-git-send-email-andre.przywara@amd.com> In-Reply-To: <1245707277-769-1-git-send-email-andre.przywara@amd.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: [PATCH 2/2] introduce -cpu host target List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Andre Przywara Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org, kvm@vger.kernel.org On 06/23/2009 12:47 AM, Andre Przywara wrote: > Although the guest's CPUID bits can be controlled in a fine grained way > in QEMU, a simple way to inject the host CPU is missing. This is handy > for KVM desktop virtualization, where one wants the guest to support the > full host feature set. > Introduce another CPU type called 'host', which will propagate the host's > CPUID bits to the guest. Problematic bits can still be turned off by using > the existing syntax (-cpu host,-skinit) > kvm already knows how to filter unknown bits to prevent runtime failures. This is even more important for qemu/tcg, since even simple bits which only define new instructions need explicit support in qemu. I think -cpu host should default to filtering unsupported bits instead of hoping the guest will ignore them or expecting the user to know which bits to remove. -- error compiling committee.c: too many arguments to function