Re: [PATCH v1 0/4] iommu/arm-smmu-v3: Allocate vmid per vsmmu instead of s2_parent

[Nicolin Chen]

On Wed, Mar 05, 2025 at 03:29:50PM -0400, Jason Gunthorpe wrote:
> On Wed, Mar 05, 2025 at 10:51:38AM -0800, Nicolin Chen wrote:
> 
> > > I mean a normal S2 domain attaching to multiple devices on multiple
> > > instances.
> > 
> > Oh, I haven't thought about a !nest_parent S2 case.
> > 
> > A nest_parent case will not allow devices to attach the S2 but
> > always to a proxy nested S1 as we discussed previously. So, I
> > think the implementation could be very different?
> 
> It could, and that is what you show here
> 
> But also, it could be the same implementation.

OK.

Obviously I underestimated this part of work.

Implementation aside, this at lease needs some assessment of any
invalidation impact. I should do some extra tracing.

Thanks
Nicolin