From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sheng Yang Subject: Re: [PATCH 4/4] KVM: VMX: Add instruction rdtscp support for guest Date: Thu, 17 Dec 2009 22:52:13 +0800 Message-ID: <200912172252.13307.sheng@linux.intel.com> References: <4B28ACC0.8050702@redhat.com> <1261042392-32426-1-git-send-email-sheng@linux.intel.com> <4B2A0A5A.60708@redhat.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm@vger.kernel.org To: Avi Kivity Return-path: Received: from mga07.intel.com ([143.182.124.22]:45792 "EHLO azsmga101.ch.intel.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750696AbZLQOwP (ORCPT ); Thu, 17 Dec 2009 09:52:15 -0500 In-Reply-To: <4B2A0A5A.60708@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Thursday 17 December 2009 18:39:22 Avi Kivity wrote: > On 12/17/2009 11:33 AM, Sheng Yang wrote: > > Before enabling, execution of "rdtscp" in guest would result in #UD. > > > > Signed-off-by: Sheng Yang > > --- > > > > Reflect guest CPUID on vmcs fields as well, but it involved some more > > code which would only executed once... Do we need a callback there for > > post-"cpuid setting"? > > I guess we do need a callback. > > > - /* Otherwise falls through to kvm_set_msr_common */ > > + ret = kvm_set_msr_common(vcpu, msr_index, data); > > + break; > > + case MSR_TSC_AUX: > > + if (!vcpu->arch.cpuid_rdtscp_enabled || !vmx_rdtscp_supported()) > > + return 1; > > + /* Check reserved bit */ > > + if ((data& 0xffff0000) != 0) > > + return 1; > > It's 0xffffffff00000000... ... /me blame himself... > > > @@ -913,6 +926,9 @@ static void setup_msrs(struct vcpu_vmx *vmx) > > index = __find_msr_index(vmx, MSR_CSTAR); > > if (index>= 0) > > move_msr_up(vmx, index, save_nmsrs++); > > + index = __find_msr_index(vmx, MSR_TSC_AUX); > > + if (index>= 0) > > + move_msr_up(vmx, index, save_nmsrs++); > > Only do this if rdtscp is enabled! /me blame himself again... -- regards Yang, Sheng