Re: [PATCH v2 06/10] iommu/arm-smmu-v3: Allocate vmid in arm_vsmmu_init

Jason Gunthorpe
2026-01-27T17:58:18Z

On Tue, Jan 27, 2026 at 09:11:14AM -0800, Nicolin Chen wrote:
> > It is easy to understand that lifecycle by just allocating it for the
> > lifetime of the VSMMU..
>
> Yea, it makes sense for that matter.
>
> So, perhaps:
>
> VMID owned by a vSMMU should be allocated in the viommu_init callback for
> - a straightforward lifecycle for a VMID used by a vSMMU
> - HW like tegra241-cmdqv needs to setup VINTF with the VMID

Yeah, the cmdqv should take the VMID from the vSMMU and that is a good
reason to pre-allocate it since it won't go through the invalidation
list.

Jason