[RFC PATCH v2 25/69] KVM: x86: Add per-VM flag to disable direct IRQ injection

[isaku . yamahata]

From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>

Add a flag to disable IRQ injection, which is not supported by TDX.

Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
 arch/x86/include/asm/kvm_host.h | 1 +
 arch/x86/kvm/x86.c              | 4 +++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 301b10172cbf..be329f0a7054 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1063,6 +1063,7 @@ struct kvm_arch {
 	bool exception_payload_enabled;
 
 	bool bus_lock_detection_enabled;
+	bool irq_injection_disallowed;
 
 	/* Deflect RDMSR and WRMSR to user space when they trigger a #GP */
 	u32 user_space_msr_mask;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b89845dfb679..4070786f17d1 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4264,7 +4264,8 @@ static int kvm_vcpu_ready_for_interrupt_injection(struct kvm_vcpu *vcpu)
 static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
 				    struct kvm_interrupt *irq)
 {
-	if (irq->irq >= KVM_NR_INTERRUPTS)
+	if (irq->irq >= KVM_NR_INTERRUPTS ||
+	    vcpu->kvm->arch.irq_injection_disallowed)
 		return -EINVAL;
 
 	if (!irqchip_in_kernel(vcpu->kvm)) {
@@ -8562,6 +8563,7 @@ static int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt)
 static int dm_request_for_irq_injection(struct kvm_vcpu *vcpu)
 {
 	return vcpu->run->request_interrupt_window &&
+	       !vcpu->kvm->arch.irq_injection_disallowed &&
 		likely(!pic_in_kernel(vcpu->kvm));
 }
 
-- 
2.25.1