Re: [PATCH RFC] iommu: Enable per-device SSID space for SVA
From: Jason Gunthorpe
Date: Sat May 09 2026 - 13:03:52 EST
On Thu, May 07, 2026 at 08:15:21AM +0000, Tian, Kevin wrote:
> if both arch and device support enqcmd-like insn...
>
> I recalled this was discussed years ago. For devices like this, just
> let driver manage its own pasid space then have a new interface
> e.g. iommu_sva_bind_device_pasid(dev, mm, pasid) to use the
> specified pasid.
Yeah, that makes sense. If the driver knows it doesn't use an ENQCMD
like programming model at all then it can use this API and it should
also avoid programming the MSRs/etc.
Jason