Re: [PATCH v5 5/6] iommu/arm-smmu-v3: Free pasid domains on iommu release

From: Jason Gunthorpe
Date: Thu Aug 03 2023 - 11:20:58 EST


On Thu, Aug 03, 2023 at 06:17:15PM +0800, Michael Shavit wrote:
> On Thu, Aug 3, 2023 at 6:14 PM Michael Shavit <mshavit@xxxxxxxxxx> wrote:
> >
> > The iommu core doesn't guarantee that pasid domains will be detached
> > before the device is released.
>
> I'm not certain whether this is possible or not. Is this change really
> necessary?

I think we should rely on the core code to detach all PASIDs prior to
calling release, drivers should not do this. I suppose that means we
have a missing bit in the core code.

FWIW, I'd like to get to a point where the core code can also
automatically attach an identity domain so that the driver's release
functions don't have to open code that either...

Thus I wouldn't do this patch..

Jason