Re: [PATCH v5 12/26] KVM: arm/arm64: GICv4: Unmap VLPI when freeing an LPI

Auger Eric
2017-11-08T14:14:03Z

Hi,

On 08/11/2017 12:52, Marc Zyngier wrote:
> On 07/11/17 20:28, Auger Eric wrote:
>> Hi Marc,
>>
>> On 27/10/2017 16:28, Marc Zyngier wrote:
>>> When freeing an LPI (on a DISCARD command, for example), we need
>>> to unmap the VLPI down to the physical ITS level.
>>>
>>> Acked-by: Christoffer Dall <cdall@linaro.org>
>>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
>>> ---
>>> virt/kvm/arm/vgic/vgic-its.c | 6 +++++-
>>> 1 file changed, 5 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
>>> index b2a678d131d0..c9b1c0967426 100644
>>> --- a/virt/kvm/arm/vgic/vgic-its.c
>>> +++ b/virt/kvm/arm/vgic/vgic-its.c
>>> @@ -628,8 +628,12 @@ static void its_free_ite(struct kvm *kvm, struct its_ite *ite)
>>> list_del(&ite->ite_list);
>>>
>>> /* This put matches the get in vgic_add_lpi. */
>>> - if (ite->irq)
>>> + if (ite->irq) {
>>> + if (ite->irq->hw)
>>> + WARN_ON(its_unmap_vlpi(ite->irq->host_irq));
>>> +
>>> vgic_put_irq(kvm, ite->irq);
>> You could have put the its_unmap_vlpi() directly in vgic_put_irq which
>> is meant to decr the ref/release the LPI irq.
>
> Do you see this as an issue?

not really. I just thought it would be nicer in vgic_put_irq but that's
a detail.

Thanks

Eric
>
> I'm trying hard to keep the GICv4 changes local to the ITS code, and not
> spread it everywhere in the vgic, but I'll happily change it if you spot
> something that seems wrong.
>
> Thanks,
>
> M.
>