From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: Xen as L1 support Date: Wed, 15 May 2013 20:45:47 +0300 Message-ID: <20130515174547.GF24814@redhat.com> References: <1B4B44D9196EFF41AE41FDA404FC0A100112FE48@SHSMSX101.ccr.corp.intel.com> <5193A2CC.9050304@redhat.com> <5193C93D.5020707@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Paolo Bonzini , "Ren, Yongjie" , Alex Palesandro , "kvm@vger.kernel.org" To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:48442 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759864Ab3EORqW (ORCPT ); Wed, 15 May 2013 13:46:22 -0400 Content-Disposition: inline In-Reply-To: <5193C93D.5020707@web.de> Sender: kvm-owner@vger.kernel.org List-ID: On Wed, May 15, 2013 at 07:43:25PM +0200, Jan Kiszka wrote: > On 2013-05-15 16:59, Paolo Bonzini wrote: > > Il 15/05/2013 03:24, Ren, Yongjie ha scritto: > >>> -----Original Message----- > >>> From: kvm-owner@vger.kernel.org [mailto:kvm-owner@vger.kernel.org] > >>> On Behalf Of Alex Palesandro > >>> Sent: Tuesday, May 14, 2013 10:51 PM > >>> To: kvm@vger.kernel.org > >>> Subject: Fwd: Xen as L1 support > >>> > >>> Hi, > >>> I'm new to KVM. I'm doing some test on nested Virtualization with Xen > >>> and KVM. I tried to test the Xen hypervisor as L1 over KVM ( Linux > >>> 3.9.0) and I found this in > >>> "xm dmesg" log ( for the complete log, see the attached file). > >>> -------------------------------------------- > >>> (XEN) VMX: CPU0 has insufficent VMExit Control (00036fff but requires > >>> min 00008200) > >>> (XEN) VMX: failed to initialise. > >>> -------------------------------------------- > > > > This is the "Acknowledge interrupt on exit" control. It shouldn't be > > hard to implement it. > > Isn't this a pretty recent feature Xen should be able to live without - > if it finds itself on a (virtually) older CPU? > IIRC the feature was always there. KVM started to use it only from 3.10 since posted interrupt requires it. -- Gleb.