[PATCH v2 8/9] KVM: x86: lapic does not have to process INIT if it is blocked

From: Paolo Bonzini
Date: Thu Aug 11 2022 - 17:06:45 EST


Do not return true from kvm_apic_has_events, and consequently from
kvm_vcpu_has_events, if the vCPU is not going to process an INIT.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/i8259.c | 2 +-
arch/x86/kvm/lapic.h | 2 +-
arch/x86/kvm/x86.c | 5 +++++
arch/x86/kvm/x86.h | 5 -----
5 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 293ff678fff5..1ce4ebc41118 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2042,6 +2042,7 @@ void __user *__x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa,
u32 size);
bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu);
bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu);
+bool kvm_vcpu_latch_init(struct kvm_vcpu *vcpu);

bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,
struct kvm_vcpu **dest_vcpu);
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index e1bb6218bb96..177555eea54e 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -29,9 +29,9 @@
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/bitops.h>
-#include "irq.h"
+#include <linux/kvm_host.h>

-#include <linux/kvm_host.h>
+#include "irq.h"
#include "trace.h"

#define pr_pic_unimpl(fmt, ...) \
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 117a46df5cc1..12577ddccdfc 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -225,7 +225,7 @@ static inline bool kvm_vcpu_apicv_active(struct kvm_vcpu *vcpu)

static inline bool kvm_apic_has_events(struct kvm_vcpu *vcpu)
{
- return lapic_in_kernel(vcpu) && vcpu->arch.apic->pending_events;
+ return lapic_in_kernel(vcpu) && vcpu->arch.apic->pending_events && !kvm_vcpu_latch_init(vcpu);
}

static inline bool kvm_lowest_prio_delivery(struct kvm_lapic_irq *irq)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0f9f24793b8a..5e9358ea112b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12529,6 +12529,11 @@ static inline bool kvm_guest_apic_has_interrupt(struct kvm_vcpu *vcpu)
static_call(kvm_x86_guest_apic_has_interrupt)(vcpu));
}

+bool kvm_vcpu_latch_init(struct kvm_vcpu *vcpu)
+{
+ return is_smm(vcpu) || static_call(kvm_x86_apic_init_signal_blocked)(vcpu);
+}
+
static inline bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu)
{
if (!list_empty_careful(&vcpu->async_pf.done))
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 1926d2cb8e79..c333e7cf933a 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -267,11 +267,6 @@ static inline bool kvm_check_has_quirk(struct kvm *kvm, u64 quirk)
return !(kvm->arch.disabled_quirks & quirk);
}

-static inline bool kvm_vcpu_latch_init(struct kvm_vcpu *vcpu)
-{
- return is_smm(vcpu) || static_call(kvm_x86_apic_init_signal_blocked)(vcpu);
-}
-
void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip);

u64 get_kvmclock_ns(struct kvm *kvm);
--
2.31.1