From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH v2] kvm: nVMX: check vmcs12 for valid activity state Date: Mon, 15 Apr 2013 15:06:52 +0200 Message-ID: <516BFB6C.2000303@siemens.com> References: <1366030827-5662-1-git-send-email-pbonzini@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "linux-kernel@vger.kernel.org" , "gnatapov@redhat.com" , "kvm@vger.kernel.org" To: Paolo Bonzini Return-path: In-Reply-To: <1366030827-5662-1-git-send-email-pbonzini@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 2013-04-15 15:00, Paolo Bonzini wrote: > KVM does not use the activity state VMCS field, and does not support > it in nested VMX either (the corresponding bits in the misc VMX feature > MSR are zero). Fail entry if the activity state is set to anything but > "active". > > Since the value will always be the same for L1 and L2, we do not need > to read and write the corresponding VMCS field on L1/L2 transitions, > either. > > Signed-off-by: Paolo Bonzini > --- > v1->v2: remove read/write of vmcs12->guest_activity_state, > use GUEST_ACTIVITY_ACTIVE. > > arch/x86/kvm/vmx.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index c75c25d..c252adf 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -7004,7 +7004,6 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) > vmcs12->vm_entry_instruction_len); > vmcs_write32(GUEST_INTERRUPTIBILITY_INFO, > vmcs12->guest_interruptibility_info); > - vmcs_write32(GUEST_ACTIVITY_STATE, vmcs12->guest_activity_state); > vmcs_write32(GUEST_SYSENTER_CS, vmcs12->guest_sysenter_cs); > kvm_set_dr(vcpu, 7, vmcs12->guest_dr7); > vmcs_writel(GUEST_RFLAGS, vmcs12->guest_rflags); > @@ -7223,6 +7222,11 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) > return 1; > } > > + if (vmcs12->guest_activity_state != GUEST_ACTIVITY_ACTIVE) { > + nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD); > + return 1; > + } > + > if ((vmcs12->cpu_based_vm_exec_control & CPU_BASED_USE_MSR_BITMAPS) && > !IS_ALIGNED(vmcs12->msr_bitmap, PAGE_SIZE)) { > /*TODO: Also verify bits beyond physical address width are 0*/ > @@ -7411,7 +7415,6 @@ static void prepare_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) > vmcs12->guest_gdtr_base = vmcs_readl(GUEST_GDTR_BASE); > vmcs12->guest_idtr_base = vmcs_readl(GUEST_IDTR_BASE); > > - vmcs12->guest_activity_state = vmcs_read32(GUEST_ACTIVITY_STATE); > vmcs12->guest_interruptibility_info = > vmcs_read32(GUEST_INTERRUPTIBILITY_INFO); > vmcs12->guest_pending_dbg_exceptions = > Reviewed-by: Jan Kiszka -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux