[PATCH 3/6] KVM: VMX: Split out the non-virtualization part of vmx_interrupt_blocked()

From: Sean Christopherson
Date: Fri Jun 07 2024 - 13:27:16 EST


Move the non-VMX chunk of the "interrupt blocked" checks to a separate
helper so that KVM can reuse the code to detect if interrupts are blocked
for L2, e.g. to determine if a virtual interrupt _for L2_ is a valid wake
event. If L1 disables HLT-exiting for L2, nested APICv is enabled, and L2
HLTs, then L2 virtual interrupts are valid wake events, but if and only if
interrupts are unblocked for L2.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/vmx/vmx.c | 13 +++++++++----
arch/x86/kvm/vmx/vmx.h | 1 +
2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 0e3aaf520db2..d8d9e1f6c340 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5050,16 +5050,21 @@ int vmx_nmi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
return !vmx_nmi_blocked(vcpu);
}

-bool vmx_interrupt_blocked(struct kvm_vcpu *vcpu)
+bool __vmx_interrupt_blocked(struct kvm_vcpu *vcpu)
{
- if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu))
- return false;
-
return !(vmx_get_rflags(vcpu) & X86_EFLAGS_IF) ||
(vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
(GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS));
}

+bool vmx_interrupt_blocked(struct kvm_vcpu *vcpu)
+{
+ if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu))
+ return false;
+
+ return __vmx_interrupt_blocked(vcpu);
+}
+
int vmx_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection)
{
if (to_vmx(vcpu)->nested.nested_run_pending)
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 08d7d67fe760..42498fa63abb 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -406,6 +406,7 @@ u64 construct_eptp(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level);
bool vmx_guest_inject_ac(struct kvm_vcpu *vcpu);
void vmx_update_exception_bitmap(struct kvm_vcpu *vcpu);
bool vmx_nmi_blocked(struct kvm_vcpu *vcpu);
+bool __vmx_interrupt_blocked(struct kvm_vcpu *vcpu);
bool vmx_interrupt_blocked(struct kvm_vcpu *vcpu);
bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu);
void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked);
--
2.45.2.505.gda0bf45e8d-goog