Re: [git pull] IOMMU Updates for Linux v6.4

From: Jacob Pan
Date: Sat May 06 2023 - 00:04:46 EST


Hi Jason,

On Sun, 30 Apr 2023 20:06:30 -0300, Jason Gunthorpe <jgg@xxxxxxxx> wrote:

> We've had this longstanding confusion in the iommu layer that SVA and
> PASID are one and the same thing, we are slowly reorganizing it.. For
> now it is fine for IOMMU_SVA to cover the PASID allocator as the only
> drivers that support PASID also support SVA.
>
> Arguably the design is backwards and IOMMU_SVA should be user
> selectable and it should turn off the SVA code entirely including the
> driver code.
>
> > Somebody should double-check my result, in other words.
>
> I didn't notice anything wrong, I'm sure Lu and Yi will test it!
FWIW, I did a quick test with SVA ENQCMD on an Intel Data Streaming
Accelerator (DSA) shared work queue, seems to work fine. Code looks good to
me too.

Thanks,

Jacob