From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751894AbaKXC0V (ORCPT ); Sun, 23 Nov 2014 21:26:21 -0500 Received: from mga14.intel.com ([192.55.52.115]:36964 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751204AbaKXC0S (ORCPT ); Sun, 23 Nov 2014 21:26:18 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,862,1389772800"; d="scan'208";a="420597268" Date: Mon, 24 Nov 2014 10:05:53 +0800 From: Wanpeng Li To: Paolo Bonzini Cc: Nadav Amit , fenghua.yu@intel.com, kvm list , Eduardo Habkost , linux-kernel@vger.kernel.org Subject: Re: KVM causes #GP on XRSTORS Message-ID: <20141124020553.GA27849@kernel> Reply-To: Wanpeng Li References: <546F505F.9080309@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <546F505F.9080309@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Paolo, On Fri, Nov 21, 2014 at 03:46:55PM +0100, Paolo Bonzini wrote: > > >On 20/11/2014 17:34, Nadav Amit wrote: >> Fenghua, >> >> I got KVM (v3.17) crashing on a machine that supports XRSTORS - It appears to get a #GP when it is trying to load the guest FPU. >> One reason for the #GP is that XCOMP_BV[63] is zeroed on the guest_fpu, but I am not sure it is the only problem. >> Was KVM ever tested with XRSTORS? > >What is the content of the CPUID[EAX=13,ECX=0] and CPUID[EAX=13,ECX=1] >leaves on the host? > >Fenghua, which processors have XSAVEC, which have XGETBV with ECX=1, and >which have XSAVES? We need to expose this in QEMU, for which I can send Skylake-client supports XSAVES. >a patch later today or next week (CCing Eduardo for this). Actually I do the xsaves work in kvm/qemu recently and the patches are complete, I will start to test it before send out. Regards, Wanpeng Li > >We will also have to uncompact the XSAVE area either in KVM_GET_XSAVE or >in QEMU. It's probably not hard to do it in the kernel. > >Paolo >-- >To unsubscribe from this list: send the line "unsubscribe kvm" in >the body of a message to majordomo@vger.kernel.org >More majordomo info at http://vger.kernel.org/majordomo-info.html