Re: [PATCH 00/11] iommufd: Enable noiommu mode for cdev

[Jason Gunthorpe]

On Fri, Feb 27, 2026 at 09:52:36AM -0800, Jacob Pan wrote:
> VFIO's unsafe_noiommu_mode has long provided a way for userspace drivers
> to operate on platforms lacking a hardware IOMMU. Today, IOMMUFD also
> supports No-IOMMU mode for group-based devices under vfio_compat mode.
> However, IOMMUFD's native character device (cdev) does not yet support
> No-IOMMU mode, which is the purpose of this patch.

I browsed through this quickly and it looks OK to me, though I might
suggest correcting that FIXME so that the get pa scans the domain for
contiguous physical address. You can copy the loop from vfio probably.

Also the kbuild error needs fixing, I gave a suggestion for that in
the thread.

Thanks,
Jason