From 913d6c9b8fe48f0836c00e359fb1ea39089d25e9 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 14 Jun 2022 21:58:31 +0000 Subject: [PATCH] KVM: nVMX: Update vmcs12 on BNDCFGS write, not at vmcs02=>vmcs12 sync Update vmcs12->guest_bndcfgs on intercepted writes to BNDCFGS from L2 instead of waiting until vmcs02 is synchronized to vmcs12. KVM always intercepts BNDCFGS accesses, so the only way the value in vmcs02 can change is via KVM's explicit VMWRITE during emulation. Signed-off-by: Sean Christopherson Message-Id: <20220614215831.3762138-6-seanjc@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/nested.c | 3 --- arch/x86/kvm/vmx/vmx.c | 6 ++++++ 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 496981b..aad938e 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4104,9 +4104,6 @@ static void sync_vmcs02_to_vmcs12_rare(struct kvm_vcpu *vcpu, vmcs12->guest_idtr_base = vmcs_readl(GUEST_IDTR_BASE); vmcs12->guest_pending_dbg_exceptions = vmcs_readl(GUEST_PENDING_DBG_EXCEPTIONS); - if ((vmx->nested.msrs.entry_ctls_high & VM_ENTRY_LOAD_BNDCFGS) || - (vmx->nested.msrs.exit_ctls_high & VM_EXIT_CLEAR_BNDCFGS)) - vmcs12->guest_bndcfgs = vmcs_read64(GUEST_BNDCFGS); vmx->nested.need_sync_vmcs02_to_vmcs12_rare = false; } diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index b4d3820..e4c16ee 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2044,6 +2044,12 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) if (is_noncanonical_address(data & PAGE_MASK, vcpu) || (data & MSR_IA32_BNDCFGS_RSVD)) return 1; + + if (is_guest_mode(vcpu) && + ((vmx->nested.msrs.entry_ctls_high & VM_ENTRY_LOAD_BNDCFGS) || + (vmx->nested.msrs.exit_ctls_high & VM_EXIT_CLEAR_BNDCFGS))) + get_vmcs12(vcpu)->guest_bndcfgs = data; + vmcs_write64(GUEST_BNDCFGS, data); break; case MSR_IA32_UMWAIT_CONTROL: -- 2.7.4