Re: [PATCH v3 08/12] KVM: arm/arm64: Check vcpu redist base before registering an iodev

Christoffer Dall
2018-04-24T21:07:59Z

On Fri, Apr 13, 2018 at 10:20:54AM +0200, Eric Auger wrote:
> As we are going to register several redist regions,
> vgic_register_all_redist_iodevs() may be called several times. We need
> to register a redist_iodev for a given vcpu only once.

Wouldn't it be more natural to change that caller to only register the
iodevs for that region?

Thanks,
-Christoffer

> So let's
> check if the base address has already been set. Initialize this latter
> in kvm_vgic_vcpu_early_init().
>
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> ---
> virt/kvm/arm/vgic/vgic-init.c | 3 +++
> virt/kvm/arm/vgic/vgic-mmio-v3.c | 3 +++
> 2 files changed, 6 insertions(+)
>
> diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
> index 6456371..7e040e7 100644
> --- a/virt/kvm/arm/vgic/vgic-init.c
> +++ b/virt/kvm/arm/vgic/vgic-init.c
> @@ -82,6 +82,9 @@ void kvm_vgic_vcpu_early_init(struct kvm_vcpu *vcpu)
> INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
> spin_lock_init(&vgic_cpu->ap_list_lock);
>
> + vgic_cpu->rd_iodev.base_addr = VGIC_ADDR_UNDEF;
> + vgic_cpu->sgi_iodev.base_addr = VGIC_ADDR_UNDEF;
> +
> /*
> * Enable and configure all SGIs to be edge-triggered and
> * configure all PPIs as level-triggered.
> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
> index 5273fb8..df23e66 100644
> --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
> +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
> @@ -592,6 +592,9 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
> gpa_t rd_base, sgi_base;
> int ret;
>
> + if (!IS_VGIC_ADDR_UNDEF(vgic_cpu->rd_iodev.base_addr))
> + return 0;
> +
> /*
> * We may be creating VCPUs before having set the base address for the
> * redistributor region, in which case we will come back to this
> --
> 2.5.5
>