Messages in this thread | | | Subject | Re: [PATCH 2/2] iommu/sva: Remove mm parameter from SVA bind API | From | Lu Baolu <> | Date | Thu, 15 Apr 2021 13:33:24 +0800 |
| |
Hi Jason,
On 4/14/21 7:26 PM, Jason Gunthorpe wrote: > On Wed, Apr 14, 2021 at 02:22:09PM +0800, Lu Baolu wrote: > >> I still worry about supervisor pasid allocation. >> >> If we use iommu_sva_alloc_pasid() to allocate a supervisor pasid, which >> mm should the pasid be set? I've ever thought about passing &init_mm to >> iommu_sva_alloc_pasid(). But if you add "mm != current->mm", this seems >> not to work. Or do you prefer a separated interface for supervisor pasid >> allocation/free? > > Without a mm_struct it is not SVA, so don't use SVA APIs for whatever > a 'supervisor pasid' is
The supervisor PASID has its mm_struct. The only difference is that the device will set priv=1 in its DMA transactions with the PASID.
Best regards, baolu
| |