On Tue, Apr 17, 2018 at 11:23:49AM +0100, Andre Przywara wrote:
> When vgic_prune_ap_list() finds an interrupt that needs to be migrated
> to a new VCPU, we should notify this VCPU of the pending interrupt,
> since it requires immediate action.
> Kick this VCPU once we have added the new IRQ to the list, but only
> after dropping the locks.
>
> Reported-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
> Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx>
Reviewed-by: Christoffer Dall <christoffer.dall@xxxxxxx>
> ---
> virt/kvm/arm/vgic/vgic.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
> index e74baec76361..4b6d72939c42 100644
> --- a/virt/kvm/arm/vgic/vgic.c
> +++ b/virt/kvm/arm/vgic/vgic.c
> @@ -594,6 +594,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
>
> list_for_each_entry_safe(irq, tmp, &vgic_cpu->ap_list_head, ap_list) {
> struct kvm_vcpu *target_vcpu, *vcpuA, *vcpuB;
> + bool target_vcpu_needs_kick = false;
>
> spin_lock(&irq->irq_lock);
>
> @@ -664,11 +665,18 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
> list_del(&irq->ap_list);
> irq->vcpu = target_vcpu;
> list_add_tail(&irq->ap_list, &new_cpu->ap_list_head);
> + target_vcpu_needs_kick = true;
> }
>
> spin_unlock(&irq->irq_lock);
> spin_unlock(&vcpuB->arch.vgic_cpu.ap_list_lock);
> spin_unlock_irqrestore(&vcpuA->arch.vgic_cpu.ap_list_lock, flags);
> +
> + if (target_vcpu_needs_kick) {
> + kvm_make_request(KVM_REQ_IRQ_PENDING, target_vcpu);
> + kvm_vcpu_kick(target_vcpu);
> + }
> +
> goto retry;
> }
>
> --
> 2.14.1
>
