From fc9465be8aad2042978590d44c01350534c1ac11 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 13 Dec 2022 06:09:06 +0000 Subject: KVM: x86: Make vmx_get_exit_qual() and vmx_get_intr_info() noinstr-friendly Add an extra special noinstr-friendly helper to test+mark a "register" available and use it when caching vmcs.EXIT_QUALIFICATION and vmcs.VM_EXIT_INTR_INFO. Make the caching helpers __always_inline too so that they can be used in noinstr functions. A future fix will move VMX's handling of NMI exits into the noinstr vmx_vcpu_enter_exit() so that the NMI is processed before any kind of instrumentation can trigger a fault and thus IRET, i.e. so that KVM doesn't invoke the NMI handler with NMIs enabled. Cc: Peter Zijlstra Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20221213060912.654668-2-seanjc@google.com Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/vmx.h | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) (limited to 'arch/x86/kvm/vmx/vmx.h') diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index a3da84f4ea45..bb720a2f11ab 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -669,25 +669,23 @@ void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu); int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu); void vmx_passthrough_lbr_msrs(struct kvm_vcpu *vcpu); -static inline unsigned long vmx_get_exit_qual(struct kvm_vcpu *vcpu) +static __always_inline unsigned long vmx_get_exit_qual(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); - if (!kvm_register_is_available(vcpu, VCPU_EXREG_EXIT_INFO_1)) { - kvm_register_mark_available(vcpu, VCPU_EXREG_EXIT_INFO_1); + if (!kvm_register_test_and_mark_available(vcpu, VCPU_EXREG_EXIT_INFO_1)) vmx->exit_qualification = vmcs_readl(EXIT_QUALIFICATION); - } + return vmx->exit_qualification; } -static inline u32 vmx_get_intr_info(struct kvm_vcpu *vcpu) +static __always_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); + if (!kvm_register_test_and_mark_available(vcpu, VCPU_EXREG_EXIT_INFO_2)) vmx->exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO); - } + return vmx->exit_intr_info; } -- cgit v1.2.3