On 1/7/25 12:36, Nicolin Chen wrote:
On Mon, Jan 06, 2025 at 10:46:21AM -0800, Nicolin Chen wrote:
On Mon, Jan 06, 2025 at 11:01:32AM +0800, Baolu Lu wrote:
Nit: I think it would be more readable to add a check in the vevent reporting helper.
diff --git a/drivers/iommu/iommufd/driver.c b/drivers/iommu/iommufd/driver.c index 77c34f8791ef..ccada0ada5ff 100644 --- a/drivers/iommu/iommufd/driver.c +++ b/drivers/iommu/iommufd/driver.c @@ -86,6 +86,9 @@ int iommufd_viommu_report_event(struct iommufd_viommu *viommu, if (WARN_ON_ONCE(!data_len || !event_data)) return -EINVAL;
if (WARN_ON_ONCE(type != IOMMU_VEVENTQ_TYPE_ARM_SMMUV3))return -EINVAL;Hmm, that's a good point I think.
down_read(&viommu->veventqs_rwsem); veventq = iommufd_viommu_find_veventq(viommu, type);^ |We actually have been missing a type validation entirely, so the type could have been rejected by this function. Perhaps we should add a static list of supported types to struct iommufd_viommu_ops for drivers to report so that then the core could reject from the first place during a vEVENTQ allocation.
I added something like this. Will send a v5.
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c index 0c7a5894ba07..348179f3cf2a 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c @@ -399,9 +399,15 @@ static int arm_vsmmu_cache_invalidate(struct iommufd_viommu *viommu, return ret; } +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;
return true; }
+}
- static const struct iommufd_viommu_ops arm_vsmmu_ops = { .alloc_domain_nested = arm_vsmmu_alloc_domain_nested, .cache_invalidate = arm_vsmmu_cache_invalidate,
- .supports_veventq = arm_vsmmu_supports_veventq, };
Others look good to me.
Thanks, baolu