| Subject | Re: [PATCH v5 17/23] KVM: arm64: GICv4.1: Let doorbells be auto-enabled | From | Auger Eric <> | Date | Tue, 17 Mar 2020 12:04:22 +0100 |
| |
Hi Marc,
On 3/4/20 9:33 PM, Marc Zyngier wrote: > As GICv4.1 understands the life cycle of doorbells (instead of > just randomly firing them at the most inconvenient time), just > enable them at irq_request time, and be done with it. > > Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
Eric
> --- > virt/kvm/arm/vgic/vgic-v4.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c > index 1eb0f8c76219..c2fcde104ea2 100644 > --- a/virt/kvm/arm/vgic/vgic-v4.c > +++ b/virt/kvm/arm/vgic/vgic-v4.c > @@ -141,6 +141,7 @@ int vgic_v4_init(struct kvm *kvm) > > kvm_for_each_vcpu(i, vcpu, kvm) { > int irq = dist->its_vm.vpes[i]->irq; > + unsigned long irq_flags = DB_IRQ_FLAGS; > > /* > * Don't automatically enable the doorbell, as we're > @@ -148,8 +149,14 @@ int vgic_v4_init(struct kvm *kvm) > * blocked. Also disable the lazy disabling, as the > * doorbell could kick us out of the guest too > * early... > + * > + * On GICv4.1, the doorbell is managed in HW and must > + * be left enabled. > */ > - irq_set_status_flags(irq, DB_IRQ_FLAGS); > + if (kvm_vgic_global_state.has_gicv4_1) > + irq_flags &= ~IRQ_NOAUTOEN; > + irq_set_status_flags(irq, irq_flags); > + > ret = request_irq(irq, vgic_v4_doorbell_handler, > 0, "vcpu", vcpu); > if (ret) { >
|