Re: [PATCH v2 03/26] iommu/amd: Detect and initialize AMD vIOMMU feature

[Jason Gunthorpe]

On Thu, May 28, 2026 at 05:17:15AM +0000, Suravee Suthikulpanit wrote:
> The feature is advertised w/ EFR[VIOMMUSup]. Please see the AMD IOMMU
> specification[1] for more detail.
> 
> Introduce a new global variable amd_iommu_viommu, which is used to
> control the feature enablement in the driver. Currently, the feature
> is default to disabled. Once the feature is fully supported, it will be
> changed to enabled by default along with a command-line option to disable
> if needed.

Still no to command line option. Just don't use iommufd if you don't
want to use it. It must have no cost until iommufd activates it.

Jason