Re: [PATCH v6 23/24] KVM: arm64: vgic-its: Fix pending table sync

Christoffer Dall
2017-05-05T14:54:07Z

On Thu, May 04, 2017 at 01:44:43PM +0200, Eric Auger wrote:
> In its_sync_lpi_pending_table() we currently ignore the
> target_vcpu of the LPIs. We sync the pending bit found in
> the vcpu pending table even if the LPI is not targeting it.
>
> Also in vgic_its_cmd_handle_invall() we are supposed to
> read the config table data for the LPIs associated to the
> collection ID. At the moment we refresh all LPI config
> information.
>
> This patch passes a vpcu to vgic_copy_lpi_list() so that
> this latter returns a snapshot of the LPIs targeting this
> CPU and only those.
>
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> ---
> virt/kvm/arm/vgic/vgic-its.c | 24 ++++++++++++------------
> 1 file changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
> index 376d963..3c114b1 100644
> --- a/virt/kvm/arm/vgic/vgic-its.c
> +++ b/virt/kvm/arm/vgic/vgic-its.c
> @@ -278,13 +278,13 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
> }
>
> /*
> - * Create a snapshot of the current LPI list, so that we can enumerate all
> - * LPIs without holding any lock.
> - * Returns the array length and puts the kmalloc'ed array into intid_ptr.
> + * Create a snapshot of the current LPIs targeting @vcpu, so that we can
> + * enumerate those LPIs without holding any lock.
> + * Returns their number and puts the kmalloc'ed array into intid_ptr.
> */
> -static int vgic_copy_lpi_list(struct kvm *kvm, u32 **intid_ptr)
> +static int vgic_copy_lpi_list(struct kvm_vcpu *vcpu, u32 **intid_ptr)
> {
> - struct vgic_dist *dist = &kvm->arch.vgic;
> + struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
> struct vgic_irq *irq;
> u32 *intids;
> int irq_count = dist->lpi_list_count, i = 0;
> @@ -303,14 +303,14 @@ static int vgic_copy_lpi_list(struct kvm *kvm, u32 **intid_ptr)
> spin_lock(&dist->lpi_list_lock);
> list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
> /* We don't need to "get" the IRQ, as we hold the list lock. */
> - intids[i] = irq->intid;
> - if (++i == irq_count)
> - break;
> + if (irq->target_vcpu != vcpu)
> + continue;
> + intids[i++] = irq->intid;
> }
> spin_unlock(&dist->lpi_list_lock);
>
> *intid_ptr = intids;
> - return irq_count;
> + return i;
> }
>
> /*
> @@ -359,7 +359,7 @@ static u32 max_lpis_propbaser(u64 propbaser)
> }
>
> /*
> - * Scan the whole LPI pending table and sync the pending bit in there
> + * Sync the pending table pending bit of LPIs targeting @vcpu
> * with our own data structures. This relies on the LPI being
> * mapped before.
> */
> @@ -372,7 +372,7 @@ static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu)
> u32 *intids;
> int nr_irqs, i;
>
> - nr_irqs = vgic_copy_lpi_list(vcpu->kvm, &intids);
> + nr_irqs = vgic_copy_lpi_list(vcpu, &intids);
> if (nr_irqs < 0)
> return nr_irqs;
>
> @@ -1055,7 +1055,7 @@ static int vgic_its_cmd_handle_invall(struct kvm *kvm, struct vgic_its *its,
>
> vcpu = kvm_get_vcpu(kvm, collection->target_addr);
>
> - irq_count = vgic_copy_lpi_list(kvm, &intids);
> + irq_count = vgic_copy_lpi_list(vcpu, &intids);
> if (irq_count < 0)
> return irq_count;
>
> --
> 2.5.5
>

Reviewed-by: Christoffer Dall <cdall@linaro.org>