Re: [PATCH v9 08/12] iommu/arm-smmu-v3-kdump: Reserve crashed kernel's ASIDs and VMIDs

[Nicolin Chen]

On Fri, Aug 21, 2026 at 08:15:26PM -0300, Jason Gunthorpe wrote:
> > Nested STE's guest-owned CD table is in IPA space and left alone: its ASIDs
> > only pair with the nonzero S2VMID being reserved, so they cannot alias this
> > kernel's VMID-0 or EL2 stage-1 domains.
> 
> This explanation is a bit off.. Nested ASIDs have a unique ASID space under
> their VMID. SO long as the VMID is reserved there is no reason to inspect the
> (VMID,ASID) list.

Updated:

A nested STE's guest-owned CD table is left alone, since its ASIDs live in
a space of their own under that STE's VMID. Reserving that VMID covers all
of them, so there is no reason for the scan to walk the (VMID, ASID) pairs
behind it. The only ASIDs needing a reservation are those in the space that
this kernel uses for its own domains.

Thanks
Nicolin