On 06/09/2018 12:12, Christian König wrote: > Am 06.09.2018 um 13:09 schrieb Jean-Philippe Brucker: >> Hi Eric, >> >> Thanks for reviewing >> >> On 05/09/2018 12:29, Auger Eric wrote: >>>> +int iommu_sva_device_init(struct device *dev, unsigned long features, >>>> + unsigned int max_pasid) >>> what about min_pasid? >> No one asked for it... The max_pasid parameter is here for drivers that >> have vendor-specific PASID size limits, such as AMD KFD (see >> kfd_iommu_device_init and >> https://patchwork.kernel.org/patch/9989307/#21389571). But in most cases >> the PASID size will only depend on the PCI PASID capability and the >> IOMMU limits, both known by the IOMMU driver, so device drivers won't >> have to set max_pasid. >> >> IOMMU drivers need to set min_pasid in the sva_device_init callback >> because it may be either 1 (e.g. Arm where PASID #0 is reserved) or 0 >> (Intel Vt-d rev2), but at the moment I can't see a reason for device >> drivers to override min_pasid > > Sorry to ruin your day, but if I'm not completely mistaken PASID zero is > reserved in the AMD KFD as well. Heh, fair enough. I'll add the min_pasid parameter Thanks, Jean