[PATCH v4 14/14] iommu/arm-smmu-v3: Report events that belong to devices attached to vIOMMU

[Baolu Lu]

On 1/7/25 14:00, Nicolin Chen wrote:
> On Tue, Jan 07, 2025 at 01:54:00PM +0800, Baolu Lu wrote:
>> On 1/7/25 12:36, Nicolin Chen wrote:
>>> +static bool arm_vsmmu_supports_veventq(unsigned int type)
>>> +{
>>> +	return type == IOMMU_VIOMMU_TYPE_ARM_SMMUV3;
>> Do you need to check the hardware capabilities before reporting this? I
>> am not familiar with the ARM architecture, but typically it's better to
>> make it like this,
>>
>> static bool arm_vsmmu_supports_veventq(struct iommufd_viommu *viommu,
>>                                         enum iommu_veventq_type type)
>> {
>> 	if (type != IOMMU_VEVENTQ_TYPE_ARM_SMMUV3)
>> 		return false;
>>
>> 	if (hardware_not_capable(viommu))
>> 		return false;
> I think the ARM version of viommu_alloc op has already implemented
> enough capability checks and rejected any of hardware_not_capable.
> So, viommu shouldn't be a thing that the driver could actually use
> to call this helper 🙂

Okay, fair enough.