From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 4/4] KVM: VMX: Add instruction rdtscp support for guest Date: Thu, 17 Dec 2009 12:39:22 +0200 Message-ID: <4B2A0A5A.60708@redhat.com> References: <4B28ACC0.8050702@redhat.com> <1261042392-32426-1-git-send-email-sheng@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm@vger.kernel.org To: Sheng Yang Return-path: Received: from mx1.redhat.com ([209.132.183.28]:36554 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751842AbZLQKjY (ORCPT ); Thu, 17 Dec 2009 05:39:24 -0500 In-Reply-To: <1261042392-32426-1-git-send-email-sheng@linux.intel.com> Sender: kvm-owner@vger.kernel.org List-ID: 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... > @@ -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! -- error compiling committee.c: too many arguments to function