From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andre Przywara Subject: Re: Setting nx bit in virtual CPU Date: Sat, 10 Apr 2010 01:45:43 +0200 Message-ID: <4BBFBC27.8040007@amd.com> References: <4BB126AC.8040401@huskydog.org.uk> <4BB45CA2.5040304@redhat.com> <4BB65C9D.3070505@huskydog.org.uk> <4BB99F03.3020208@redhat.com> <4BBBB63B.60007@huskydog.org.uk> <4BBC1A86.6080506@redhat.com> <4BBC7645.2070904@huskydog.org.uk> <4BBC7958.9010903@redhat.com> <4BBCED32.30304@huskydog.org.uk> <4BBCEFA5.3050900@redhat.com> <4BBD995F.60705@amd.com> <4BBE4967.9020201@huskydog.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Cc: kvm To: Richard Simpson , Avi Kivity Return-path: Received: from tx2ehsobe004.messaging.microsoft.com ([65.55.88.14]:14940 "EHLO TX2EHSOBE007.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754278Ab0DIXoN (ORCPT ); Fri, 9 Apr 2010 19:44:13 -0400 In-Reply-To: <4BBE4967.9020201@huskydog.org.uk> Sender: kvm-owner@vger.kernel.org List-ID: Richard Simpson wrote: > On 08/04/10 09:52, Andre Przywara wrote: > >> Can you try to boot the attached multiboot "kernel", which just outputs >> a brief CPUID dump? >> $ qemu-kvm -kernel cpuid_mb -vnc :0 >> (Unfortunately I have no serial console support in there yet, so you >> either have to write the values down or screenshot it). >> In the 4th line from the button it should print NX (after SYSCALL). > > OK, that was fun! Resulting screen shots are attached. > > ...default.png With command line above. > ...cpu_host.png With -cpu host option added. > ...no_kvm.png With -no-kvm option added. > > I hope that helps! OK, AFAIK there are several flags missing. I dimly remember there was a bug with masking the CPUID bits in older kernels, so I guess you have to celebrate your uptime for the last time and then give it a reboot with a more up-to-date host kernel. (I also rebooted my desktop after I made the one year and now am gone green with turning it off over night ;-) Maybe you get around with rebuilding fixed versions of kvm.ko and kvm_amd.ko, I can provide a fix for you if you wish (please point me to a way to get the actual kernel source you use). The userspace was up-to-date? (qemu-kvm 0.12.3)? Regards, Andre. -- Andre Przywara AMD-Operating System Research Center (OSRC), Dresden, Germany Tel: +49 351 488-3567-12