Re: [PATCH v10 04/12] iommu: Add attach/detach_dev_pasid iommu interface

From: Jason Gunthorpe
Date: Thu Jul 28 2022 - 12:59:34 EST


On Thu, Jul 28, 2022 at 03:06:47AM +0000, Tian, Kevin wrote:

> > Then we don't need this weirdo check in the core iommu code at all.
>
> and then we could also move group->pasid_array to device->pasid_array
> with this approach. Though the end result doesn't change i.e. still only
> the singleton group can enable pasid the iommu core can just stick to
> the device manner now.

I don't see why, the group is still logically the unit of attachment
in the iommu area, and if we have a multi-device group it just means
we iterate over all the devices in the group when doing pasid set, no
different than a RID.

Jason