[RFC PATCH v7 10/78] KVM: x86: add .bp_intercepted() to struct kvm_x86_ops

["Adalbert Lazăr" <alazar@bitdefender.com>]

From: Nicușor Cîțu <ncitu@bitdefender.com>

The introspection tool and the userspace could request #BP
interception. This function will be used to check if the interception
is already enabled.

Signed-off-by: Nicușor Cîțu <ncitu@bitdefender.com>
Signed-off-by: Adalbert Lazăr <alazar@bitdefender.com>
---
 arch/x86/include/asm/kvm_host.h |  1 +
 arch/x86/kvm/svm.c              | 15 +++++++++++++++
 arch/x86/kvm/vmx/vmx.c          |  6 ++++++
 3 files changed, 22 insertions(+)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b79cd6aa4075..d279195dac97 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1048,6 +1048,7 @@ struct kvm_x86_ops {
 	void (*vcpu_load)(struct kvm_vcpu *vcpu, int cpu);
 	void (*vcpu_put)(struct kvm_vcpu *vcpu);
 
+	bool (*bp_intercepted)(struct kvm_vcpu *vcpu);
 	void (*update_bp_intercept)(struct kvm_vcpu *vcpu);
 	int (*get_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr);
 	int (*set_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr);
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 122d4ce3b1ab..df34ab0da4ff 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -607,6 +607,13 @@ static inline void clr_exception_intercept(struct vcpu_svm *svm, int bit)
 	recalc_intercepts(svm);
 }
 
+static inline bool get_exception_intercept(struct vcpu_svm *svm, int bit)
+{
+	struct vmcb *vmcb = get_host_vmcb(svm);
+
+	return (vmcb->control.intercept_exceptions & (1U << bit));
+}
+
 static inline void set_intercept(struct vcpu_svm *svm, int bit)
 {
 	struct vmcb *vmcb = get_host_vmcb(svm);
@@ -7242,6 +7249,13 @@ static bool svm_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
 		   (svm->vmcb->control.intercept & (1ULL << INTERCEPT_INIT));
 }
 
+static inline bool svm_bp_intercepted(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_svm *svm = to_svm(vcpu);
+
+	return get_exception_intercept(svm, BP_VECTOR);
+}
+
 static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
 	.cpu_has_kvm_support = has_svm,
 	.disabled_by_bios = is_disabled,
@@ -7268,6 +7282,7 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
 	.vcpu_blocking = svm_vcpu_blocking,
 	.vcpu_unblocking = svm_vcpu_unblocking,
 
+	.bp_intercepted = svm_bp_intercepted,
 	.update_bp_intercept = update_bp_intercept,
 	.get_msr_feature = svm_get_msr_feature,
 	.get_msr = svm_get_msr,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index e3394c839dea..0d7ca70b310e 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7758,6 +7758,11 @@ static __exit void hardware_unsetup(void)
 	free_kvm_area();
 }
 
+static bool vmx_bp_intercepted(struct kvm_vcpu *vcpu)
+{
+	return (vmcs_read32(EXCEPTION_BITMAP) & (1u << BP_VECTOR));
+}
+
 static struct kvm_x86_ops vmx_x86_ops __ro_after_init = {
 	.cpu_has_kvm_support = cpu_has_kvm_support,
 	.disabled_by_bios = vmx_disabled_by_bios,
@@ -7781,6 +7786,7 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = {
 	.vcpu_load = vmx_vcpu_load,
 	.vcpu_put = vmx_vcpu_put,
 
+	.bp_intercepted = vmx_bp_intercepted,
 	.update_bp_intercept = update_exception_bitmap,
 	.get_msr_feature = vmx_get_msr_feature,
 	.get_msr = vmx_get_msr,