From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: KVM: VMX: update cr0 read shadow when deactivating cr0.ts passthrough Date: Mon, 1 Feb 2010 14:48:27 -0200 Message-ID: <20100201164827.GA3225@amt.cnet> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity To: kvm Return-path: Received: from mx1.redhat.com ([209.132.183.28]:25898 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753764Ab0BAQtE (ORCPT ); Mon, 1 Feb 2010 11:49:04 -0500 Received: from int-mx03.intmail.prod.int.phx2.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.16]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o11Gn44T027541 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 1 Feb 2010 11:49:04 -0500 Content-Disposition: inline Sender: kvm-owner@vger.kernel.org List-ID: On fpu deactivation, the cr0 read shadow is not properly updated, since it assumes vcpu->arch.cr0 contains the guest visible cr0 value before guest had control of cr0.ts. This is not true, since cr0 has been decached (from vmx_fpu_deactivate itself or somewhere else). Fix by unconditionally updating cr0 read shadow (this is not a hot path, in comparison with entry/exit). Fixes FC8 64 install. Signed-off-by: Marcelo Tosatti diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index c1d864a..334b016 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -805,19 +805,16 @@ static void vmx_fpu_activate(struct kvm_vcpu *vcpu) vmcs_writel(CR0_GUEST_HOST_MASK, ~vcpu->arch.cr0_guest_owned_bits); } +static void vmx_decache_cr0_guest_bits(struct kvm_vcpu *vcpu); + static void vmx_fpu_deactivate(struct kvm_vcpu *vcpu) { - ulong old_ts, old_cr0; - - old_ts = kvm_read_cr0_bits(vcpu, X86_CR0_TS); + vmx_decache_cr0_guest_bits(vcpu); vmcs_set_bits(GUEST_CR0, X86_CR0_TS | X86_CR0_MP); update_exception_bitmap(vcpu); vcpu->arch.cr0_guest_owned_bits = 0; vmcs_writel(CR0_GUEST_HOST_MASK, ~vcpu->arch.cr0_guest_owned_bits); - old_cr0 = vcpu->arch.cr0; - vcpu->arch.cr0 = (vcpu->arch.cr0 & ~X86_CR0_TS) | old_ts; - if (vcpu->arch.cr0 != old_cr0) - vmcs_writel(CR0_READ_SHADOW, vcpu->arch.cr0); + vmcs_writel(CR0_READ_SHADOW, vcpu->arch.cr0); } static unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu)