From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 2/2] introduce -cpu host target Date: Tue, 23 Jun 2009 13:04:01 +0300 Message-ID: <4A40A891.4010606@redhat.com> References: <1245707277-769-1-git-send-email-andre.przywara@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org, kvm@vger.kernel.org To: Andre Przywara Return-path: Received: from mx2.redhat.com ([66.187.237.31]:35015 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751973AbZFWKDK (ORCPT ); Tue, 23 Jun 2009 06:03:10 -0400 In-Reply-To: <1245707277-769-1-git-send-email-andre.przywara@amd.com> Sender: kvm-owner@vger.kernel.org List-ID: 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