[PATCH v4 08/38] KVM: x86/pmu: Register KVM_GUEST_PMI_VECTOR handler

[Mingwei Zhang]

From: Xiong Zhang <xiong.y.zhang@xxxxxxxxxxxxxxx>

Add function to register/unregister guest KVM PMI handler at KVM module
initialization and destroy. This allows the host PMU with passthough
capability enabled can switch PMI handler at PMU context switch.

Signed-off-by: Xiong Zhang <xiong.y.zhang@xxxxxxxxxxxxxxx>
Tested-by: Yongwei Ma <yongwei.ma@xxxxxxxxx>
Signed-off-by: Mingwei Zhang <mizhang@xxxxxxxxxx>
---
 arch/x86/kvm/x86.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 02159c967d29..72995952978a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -13984,6 +13984,16 @@ int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size,
 }
 EXPORT_SYMBOL_GPL(kvm_sev_es_string_io);
 
+static void kvm_handle_guest_pmi(void)
+{
+	struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
+
+	if (WARN_ON_ONCE(!vcpu))
+		return;
+
+	kvm_make_request(KVM_REQ_PMI, vcpu);
+}
+
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_entry);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio);
@@ -14021,12 +14031,14 @@ static int __init kvm_x86_init(void)
 
 	kvm_mmu_x86_module_init();
 	mitigate_smt_rsb &= boot_cpu_has_bug(X86_BUG_SMT_RSB) && cpu_smt_possible();
+	x86_set_kvm_irq_handler(KVM_GUEST_PMI_VECTOR, kvm_handle_guest_pmi);
 	return 0;
 }
 module_init(kvm_x86_init);
 
 static void __exit kvm_x86_exit(void)
 {
+	x86_set_kvm_irq_handler(KVM_GUEST_PMI_VECTOR, NULL);
 	WARN_ON_ONCE(static_branch_unlikely(&kvm_has_noapic_vcpu));
 }
 module_exit(kvm_x86_exit);
-- 
2.49.0.395.g12beb8f557-goog