KVM: x86: Skip KVM_GUESTDBG_BLOCKIRQ APICv update if APICv is disabled

Skip the APICv inhibit update for KVM_GUESTDBG_BLOCKIRQ if APICv is
disabled at the module level to avoid having to acquire the mutex and
potentially process all vCPUs. The DISABLE inhibit will (barring bugs)
never be lifted, so piling on more inhibits is unnecessary.

Fixes: cae72dcc3b ("KVM: x86: inhibit APICv when KVM_GUESTDBG_BLOCKIRQ active")
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220420013732.3308816-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2022-04-20 01:37:32 +00:00 committed by Paolo Bonzini
parent 423ecfea77
commit 0047fb33f8

View file

@ -10978,6 +10978,9 @@ static void kvm_arch_vcpu_guestdbg_update_apicv_inhibit(struct kvm *kvm)
struct kvm_vcpu *vcpu;
unsigned long i;
if (!enable_apicv)
return;
down_write(&kvm->arch.apicv_update_lock);
kvm_for_each_vcpu(i, vcpu, kvm) {