On Wed, Mar 24, 2021 at 10:02:46AM -0700, Jacob Pan wrote:

quoted

And a flag IOMMU_SVA_BIND_SUPERVISOR (not that I plan to implement it in
the SMMU, but I think we need to clean the current usage)

You mean move #define SVM_FLAG_SUPERVISOR_MODE out of Intel code to be a
generic flag in iommu-sva-lib.h called IOMMU_SVA_BIND_SUPERVISOR?

Yes, though it would need to be in iommu.h since it's used by device
drivers

quoted

Also wondering about device driver allocating auxiliary domains for their
private use, to do iommu_map/unmap on private PASIDs (a clean replacement
to super SVA, for example). Would that go through the same path as
/dev/ioasid and use the cgroup of current task?

For the in-kernel private use, I don't think we should restrict based on
cgroup, since there is no affinity to user processes. I also think the
PASID allocation should just use kernel API instead of /dev/ioasid. Why
would user space need to know the actual PASID # for device private domains?
Maybe I missed your idea?

No that's my bad, I didn't get the role of /dev/ioasid. Let me give the
series a proper read.

Thanks,
Jean