From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: KVM: VMX: fix incorrect cached cpl value with real/v8086 modes (v2) Date: Thu, 3 Jan 2013 11:49:57 -0200 Message-ID: <20130103134957.GA3266@amt.cnet> References: <20121219132926.GA3551@amt.cnet> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm To: Gleb Natapov , Avi Kivity Return-path: Received: from mx1.redhat.com ([209.132.183.28]:27540 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753236Ab3ACPN7 (ORCPT ); Thu, 3 Jan 2013 10:13:59 -0500 Content-Disposition: inline In-Reply-To: <20121219132926.GA3551@amt.cnet> Sender: kvm-owner@vger.kernel.org List-ID: CPL is always 0 when in real mode, and always 3 when virtual 8086 mode. Using values other than those can cause failures on operations that check CPL. Signed-off-by: Marcelo Tosatti diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 55dfc37..849f5f2 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -1696,7 +1696,6 @@ static unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu) static void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags) { __set_bit(VCPU_EXREG_RFLAGS, (ulong *)&vcpu->arch.regs_avail); - __clear_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail); to_vmx(vcpu)->rflags = rflags; if (to_vmx(vcpu)->rmode.vm86_active) { to_vmx(vcpu)->rmode.save_rflags = rflags; @@ -3220,8 +3219,10 @@ static u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg) return vmx_read_guest_seg_base(to_vmx(vcpu), seg); } -static int __vmx_get_cpl(struct kvm_vcpu *vcpu) +static int vmx_get_cpl(struct kvm_vcpu *vcpu) { + struct vcpu_vmx *vmx = to_vmx(vcpu); + if (!is_protmode(vcpu)) return 0; @@ -3229,13 +3230,6 @@ static int __vmx_get_cpl(struct kvm_vcpu *vcpu) && (kvm_get_rflags(vcpu) & X86_EFLAGS_VM)) /* if virtual 8086 */ return 3; - return vmx_read_guest_seg_selector(to_vmx(vcpu), VCPU_SREG_CS) & 3; -} - -static int vmx_get_cpl(struct kvm_vcpu *vcpu) -{ - struct vcpu_vmx *vmx = to_vmx(vcpu); - /* * If we enter real mode with cs.sel & 3 != 0, the normal CPL calculations * fail; use the cache instead. @@ -3246,7 +3240,7 @@ static int vmx_get_cpl(struct kvm_vcpu *vcpu) if (!test_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail)) { __set_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail); - vmx->cpl = __vmx_get_cpl(vcpu); + vmx->cpl = vmx_read_guest_seg_selector(vmx, VCPU_SREG_CS) & 3; } return vmx->cpl;