Re: [PATCH v3 7/9] KVM: arm/arm64: Check if irq lines to the GIC are already used

[Marc Zyngier <marc.zyngier@arm.com>]

On Thu, Jun 08 2017 at  3:34:44 pm BST, Christoffer Dall <cdall@linaro.org> wrote:
> We check if other in-kernel devices have already been connected to the
> GIC for a particular interrupt line when possible.
>
> For the PMU, we can do this whenever setting the PMU interrupt number
> from userspace.
>
> For the timers, we have to wait until we try to enable the timer,
> because we have a concept of default IRQ numbers that userspace
> shouldn't have to work around in the initialization phase.
>
> Signed-off-by: Christoffer Dall <cdall@linaro.org>
> ---
>  virt/kvm/arm/arch_timer.c | 18 ++++++++++--------
>  virt/kvm/arm/pmu.c        |  7 +++++++
>  2 files changed, 17 insertions(+), 8 deletions(-)
>
> diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
> index e03da1a..07f6f9b 100644
> --- a/virt/kvm/arm/arch_timer.c
> +++ b/virt/kvm/arm/arch_timer.c
> @@ -618,20 +618,22 @@ void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu)
>  	kvm_vgic_unmap_phys_irq(vcpu, vtimer->irq.irq);
>  }
>  
> -static bool timer_irqs_are_valid(struct kvm *kvm)
> +static bool timer_irqs_are_valid(struct kvm_vcpu *vcpu)
>  {
> -	struct kvm_vcpu *vcpu;
>  	int vtimer_irq, ptimer_irq;
> -	int i;
> +	int i, ret;
>  
> -	vcpu = kvm_get_vcpu(kvm, 0);
>  	vtimer_irq = vcpu_vtimer(vcpu)->irq.irq;
> -	ptimer_irq = vcpu_ptimer(vcpu)->irq.irq;
> +	ret = kvm_vgic_set_owner(vcpu, vtimer_irq, vcpu_vtimer(vcpu));
> +	if (ret)
> +		return false;
>  
> -	if (vtimer_irq == ptimer_irq)
> +	ptimer_irq = vcpu_ptimer(vcpu)->irq.irq;
> +	ret = kvm_vgic_set_owner(vcpu, ptimer_irq, vcpu_ptimer(vcpu));
> +	if (ret)
>  		return false;
>  
> -	kvm_for_each_vcpu(i, vcpu, kvm) {
> +	kvm_for_each_vcpu(i, vcpu, vcpu->kvm) {
>  		if (vcpu_vtimer(vcpu)->irq.irq != vtimer_irq ||
>  		    vcpu_ptimer(vcpu)->irq.irq != ptimer_irq)
>  			return false;
> @@ -659,7 +661,7 @@ int kvm_timer_enable(struct kvm_vcpu *vcpu)
>  	if (!vgic_initialized(vcpu->kvm))
>  		return -ENODEV;
>  
> -	if (!timer_irqs_are_valid(vcpu->kvm)) {
> +	if (!timer_irqs_are_valid(vcpu)) {
>  		kvm_debug("incorrectly configured timer irqs\n");
>  		return -EINVAL;
>  	}
> diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
> index 574feff..3f08669 100644
> --- a/virt/kvm/arm/pmu.c
> +++ b/virt/kvm/arm/pmu.c
> @@ -480,6 +480,8 @@ static int kvm_arm_pmu_v3_init(struct kvm_vcpu *vcpu)
>  		return -EBUSY;
>  
>  	if (irqchip_in_kernel(vcpu->kvm)) {
> +		int ret;
> +
>  		/*
>  		 * If using the PMU with an in-kernel virtual GIC
>  		 * implementation, we require the GIC to be already
> @@ -490,6 +492,11 @@ static int kvm_arm_pmu_v3_init(struct kvm_vcpu *vcpu)
>  
>  		if (!kvm_arm_pmu_irq_initialized(vcpu))
>  			return -ENXIO;
> +
> +		ret = kvm_vgic_set_owner(vcpu, vcpu->arch.pmu.irq_num,
> +					 &vcpu->arch.pmu);
> +		if (ret)
> +			return ret;
>  	}
>  
>  	vcpu->arch.pmu.created = true;

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>

	M.
-- 
Jazz is not dead, it just smell funny.