KVM: x86: Rename and expose helper to detect if INIT/SIPI are allowed

Rename and invert kvm_vcpu_latch_init() to kvm_apic_init_sipi_allowed()
so as to match the behavior of {interrupt,nmi,smi}_allowed(), and expose
the helper so that it can be used by kvm_vcpu_has_events() to determine
whether or not an INIT or SIPI is pending _and_ can be taken immediately.

Opportunistically replaced usage of the "latch" terminology with "blocked"
and/or "allowed", again to align with KVM's terminology used for all other
event types.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220921003201.1441511-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 9dda989..2bd90ef 100644 (file)
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -3051,14 +3051,14 @@ int kvm_apic_accept_events(struct kvm_vcpu *vcpu)
        }
 
        /*
-        * INITs are latched while CPU is in specific states
+        * INITs are blocked while CPU is in specific states
         * (SMM, VMX root mode, SVM with GIF=0).
         * Because a CPU cannot be in these states immediately
         * after it has processed an INIT signal (and thus in
         * KVM_MP_STATE_INIT_RECEIVED state), just eat SIPIs
         * and leave the INIT pending.
         */
-       if (kvm_vcpu_latch_init(vcpu)) {
+       if (!kvm_apic_init_sipi_allowed(vcpu)) {
                WARN_ON_ONCE(vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED);
                if (test_bit(KVM_APIC_SIPI, &pe))
                        clear_bit(KVM_APIC_SIPI, &apic->pending_events);

diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 117a46d..c3ce6b0 100644 (file)
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -7,6 +7,7 @@
 #include <linux/kvm_host.h>
 
 #include "hyperv.h"
+#include "kvm_cache_regs.h"
 
 #define KVM_APIC_INIT          0
 #define KVM_APIC_SIPI          1
@@ -228,6 +229,12 @@ static inline bool kvm_apic_has_events(struct kvm_vcpu *vcpu)
        return lapic_in_kernel(vcpu) && vcpu->arch.apic->pending_events;
 }
 
+static inline bool kvm_apic_init_sipi_allowed(struct kvm_vcpu *vcpu)
+{
+       return !is_smm(vcpu) &&
+              !static_call(kvm_x86_apic_init_signal_blocked)(vcpu);
+}
+
 static inline bool kvm_lowest_prio_delivery(struct kvm_lapic_irq *irq)
 {
        return (irq->delivery_mode == APIC_DM_LOWEST ||

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 10f2895..bc8f8cd 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -11295,11 +11295,12 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
                goto out;
 
        /*
-        * KVM_MP_STATE_INIT_RECEIVED means the processor is in
-        * INIT state; latched init should be reported using
-        * KVM_SET_VCPU_EVENTS, so reject it here.
+        * Pending INITs are reported using KVM_SET_VCPU_EVENTS, disallow
+        * forcing the guest into INIT/SIPI if those events are supposed to be
+        * blocked.  KVM prioritizes SMI over INIT, so reject INIT/SIPI state
+        * if an SMI is pending as well.
         */
-       if ((kvm_vcpu_latch_init(vcpu) || vcpu->arch.smi_pending) &&
+       if ((!kvm_apic_init_sipi_allowed(vcpu) || vcpu->arch.smi_pending) &&
            (mp_state->mp_state == KVM_MP_STATE_SIPI_RECEIVED ||
             mp_state->mp_state == KVM_MP_STATE_INIT_RECEIVED))
                goto out;

diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index a784ff9..829d313 100644 (file)
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -275,11 +275,6 @@ 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);