[RFC PATCH v3 16/59] KVM: x86: Add per-VM flag to disable direct IRQ injection

isaku.yamahata
2021-11-25T00:25:15Z

From: Sean Christopherson <sean.j.christopherson@intel.com>

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

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
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 cdb908ed7d5b..ebc4de32bf0e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1141,6 +1141,7 @@ struct kvm_arch {
bool exception_payload_enabled;

bool bus_lock_detection_enabled;
+ bool irq_injection_disallowed;
/*
* If exit_on_emulation_error is set, and the in-kernel instruction
* emulator fails to emulate an instruction, allow userspace
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b21fcf3c0cc8..b399e64e8863 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4506,7 +4506,8 @@ 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)) {
@@ -8997,6 +8998,7 @@ 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