[v8,10/81] KVM: x86: add .bp_intercepted() to struct kvm_x86_ops

Commit Message

Adalbert Lazăr March 30, 2020, 10:11 a.m. UTC

From: Nicușor Cîțu <[e-mail]>

The introspection tool and the userspace can request #BP interception.
This function will be used to check if this interception is enabled
by either side.

Signed-off-by: Nicușor Cîțu <[e-mail]>
Signed-off-by: Adalbert Lazăr <[e-mail]>
---
 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(+)

Patch

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 98959e8cd448..afc5bf3fa730 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1077,6 +1077,7 @@  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 50d1ebafe0b3..73871f28ad7b 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -611,6 +611,13 @@  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);
@@ -7393,6 +7400,13 @@  static void svm_pre_update_apicv_exec_ctrl(struct kvm *kvm, bool activate)
 	avic_update_access_page(kvm, activate);
 }
 
+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,
@@ -7419,6 +7433,7 @@  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 079d9fbf278e..eee8d81f7083 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7849,6 +7849,11 @@  static bool vmx_check_apicv_inhibit_reasons(ulong bit)
 	return supported & BIT(bit);
 }
 
+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,
@@ -7872,6 +7877,7 @@  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,