KVM: VMX: Cache vmcs.EXIT_INTR_INFO using arch avail_reg flags

Introduce a new "extended register" type, EXIT_INFO_2 (to pair with the
nomenclature in .get_exit_info()), and use it to cache VMX's
vmcs.EXIT_INTR_INFO.  Drop a comment in vmx_recover_nmi_blocking() that
is obsoleted by the generic caching mechanism.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200415203454.8296-6-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 9673ec700cd0fbe565b610720771e24c596f4a27..ceba205d32a2bb9136311c4a3594fb534018412d 100644 (file)
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -171,6 +171,7 @@ enum kvm_reg {
        VCPU_EXREG_RFLAGS,
        VCPU_EXREG_SEGMENTS,
        VCPU_EXREG_EXIT_INFO_1,
+       VCPU_EXREG_EXIT_INFO_2,
 };
 
 enum {

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index dc16b2f8ce975736bba2e0eb8d3f733a0c200051..78744c6e4a04c2a39f8da4e0cf90ffa5af74bbcb 100644 (file)
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -5419,7 +5419,7 @@ static int handle_vmfunc(struct kvm_vcpu *vcpu)
 
 fail:
        nested_vmx_vmexit(vcpu, vmx->exit_reason,
-                         vmcs_read32(VM_EXIT_INTR_INFO),
+                         vmx_get_intr_info(vcpu),
                          vmx_get_exit_qual(vcpu));
        return 1;
 }
@@ -5652,7 +5652,7 @@ static bool nested_vmx_l0_wants_exit(struct kvm_vcpu *vcpu, u32 exit_reason)
 
        switch (exit_reason) {
        case EXIT_REASON_EXCEPTION_NMI:
-               intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
+               intr_info = vmx_get_intr_info(vcpu);
                if (is_nmi(intr_info))
                        return true;
                else if (is_page_fault(intr_info))
@@ -5708,12 +5708,12 @@ static bool nested_vmx_l0_wants_exit(struct kvm_vcpu *vcpu, u32 exit_reason)
  */
 static bool nested_vmx_l1_wants_exit(struct kvm_vcpu *vcpu, u32 exit_reason)
 {
+       u32 intr_info = vmx_get_intr_info(vcpu);
        struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
-       u32 intr_info;
 
        switch (exit_reason) {
        case EXIT_REASON_EXCEPTION_NMI:
-               intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
+               intr_info = vmx_get_intr_info(vcpu);
                if (is_nmi(intr_info))
                        return true;
                else if (is_page_fault(intr_info))
@@ -5848,7 +5848,7 @@ bool nested_vmx_reflect_vmexit(struct kvm_vcpu *vcpu)
                goto reflect_vmexit;
        }
 
-       exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
+       exit_intr_info = vmx_get_intr_info(vcpu);
        exit_qual = vmx_get_exit_qual(vcpu);
 
        trace_kvm_nested_vmexit(kvm_rip_read(vcpu), exit_reason, exit_qual,

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index b7aab2284a9c46126702018f8a869252f42b41c6..50951cdbe76f7359bf9f08926e87662956206cf7 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5635,7 +5635,7 @@ static const int kvm_vmx_max_exit_handlers =
 static void vmx_get_exit_info(struct kvm_vcpu *vcpu, u64 *info1, u64 *info2)
 {
        *info1 = vmx_get_exit_qual(vcpu);
-       *info2 = vmcs_read32(VM_EXIT_INTR_INFO);
+       *info2 = vmx_get_intr_info(vcpu);
 }
 
 static void vmx_destroy_pml_buffer(struct vcpu_vmx *vmx)
@@ -6298,16 +6298,16 @@ static void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu)
 
 static void handle_exception_nmi_irqoff(struct vcpu_vmx *vmx)
 {
-       vmx->exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
+       u32 intr_info = vmx_get_intr_info(&vmx->vcpu);
 
        /* if exit due to PF check for async PF */
-       if (is_page_fault(vmx->exit_intr_info)) {
+       if (is_page_fault(intr_info)) {
                vmx->vcpu.arch.apf.host_apf_reason = kvm_read_and_reset_pf_reason();
        /* Handle machine checks before interrupts are enabled */
-       } else if (is_machine_check(vmx->exit_intr_info)) {
+       } else if (is_machine_check(intr_info)) {
                kvm_machine_check();
        /* We need to handle NMIs before interrupts are enabled */
-       } else if (is_nmi(vmx->exit_intr_info)) {
+       } else if (is_nmi(intr_info)) {
                kvm_before_interrupt(&vmx->vcpu);
                asm("int $2");
                kvm_after_interrupt(&vmx->vcpu);
@@ -6322,9 +6322,8 @@ static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu)
        unsigned long tmp;
 #endif
        gate_desc *desc;
-       u32 intr_info;
+       u32 intr_info = vmx_get_intr_info(vcpu);
 
-       intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
        if (WARN_ONCE(!is_external_intr(intr_info),
            "KVM: unexpected VM-Exit interrupt info: 0x%x", intr_info))
                return;
@@ -6405,11 +6404,8 @@ static void vmx_recover_nmi_blocking(struct vcpu_vmx *vmx)
        if (enable_vnmi) {
                if (vmx->loaded_vmcs->nmi_known_unmasked)
                        return;
-               /*
-                * Can't use vmx->exit_intr_info since we're not sure what
-                * the exit reason is.
-                */
-               exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
+
+               exit_intr_info = vmx_get_intr_info(&vmx->vcpu);
                unblock_nmi = (exit_intr_info & INTR_INFO_UNBLOCK_NMI) != 0;
                vector = exit_intr_info & INTR_INFO_VECTOR_MASK;
                /*

diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index a13eafec67fc271d8974fbdc3633a62b8d691184..edfb739e590747f4fb9b292318bf1f88d2c50bc4 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -451,7 +451,8 @@ static inline void vmx_register_cache_reset(struct kvm_vcpu *vcpu)
                                  | (1 << VCPU_EXREG_PDPTR)
                                  | (1 << VCPU_EXREG_SEGMENTS)
                                  | (1 << VCPU_EXREG_CR3)
-                                 | (1 << VCPU_EXREG_EXIT_INFO_1));
+                                 | (1 << VCPU_EXREG_EXIT_INFO_1)
+                                 | (1 << VCPU_EXREG_EXIT_INFO_2));
        vcpu->arch.regs_dirty = 0;
 }
 
@@ -506,6 +507,17 @@ static inline unsigned long vmx_get_exit_qual(struct kvm_vcpu *vcpu)
        return vmx->exit_qualification;
 }
 
+static inline u32 vmx_get_intr_info(struct kvm_vcpu *vcpu)
+{
+       struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+       if (!kvm_register_is_available(vcpu, VCPU_EXREG_EXIT_INFO_2)) {
+               kvm_register_mark_available(vcpu, VCPU_EXREG_EXIT_INFO_2);
+               vmx->exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
+       }
+       return vmx->exit_intr_info;
+}
+
 struct vmcs *alloc_vmcs_cpu(bool shadow, int cpu, gfp_t flags);
 void free_vmcs(struct vmcs *vmcs);
 int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs);