From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: expose host CPU features to guests Date: Wed, 05 Sep 2007 22:34:45 +0300 Message-ID: <46DF04D5.5000807@qumranet.com> References: <20070905174530.GA3945@karma.qumranet.com> <1189020371.7206.3.camel@squirrel> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel , qemu-devel-qX2TKyscuCcdnm+yROfE0A@public.gmane.org To: Anthony Liguori Return-path: In-Reply-To: <1189020371.7206.3.camel@squirrel> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Anthony Liguori wrote: > On Wed, 2007-09-05 at 20:45 +0300, danken-atKUWr5tajBWk0Htik3J/w@public.gmane.org wrote: > >> Hi, >> >> It's a pity not to use a host CPU feature if it is available. This patch >> exposes host CPU features to guests. It allows fine-tuning the presented >> features from the command-line. >> >> The code could use some serious clean ups, but I think it is interesting >> enough right now. I'd be happy to hear your opinion and suggestions. >> The diff are done against qemu cvs. I tried it with kvm, but I thinkg it >> should be useful also for kqemu. >> > > I like this idea but I have some suggestions about the general approach. > I think instead of defining another machine type, it would be better to > just have a command line option like -cpuid that took a comma separate > string of features with "all" meaning all features that the host has. > > I think qemu-cvs has a -cpu option for non-x86 which could be used for this. Agree machine types are the wrong approach. > I also think it would be nicer to use cpuid() directly instead of > attempting to parse /proc/cpuinfo. > Yes. -- Any sufficiently difficult bug is indistinguishable from a feature. ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/