Re: [PATCH v5 4/4] iommu/s390: implement iommu passthrough via identity domain

[Jason Gunthorpe]

On Wed, Feb 12, 2025 at 04:34:18PM -0500, Matthew Rosato wrote:
> Enabled via the kernel command-line 'iommu.passthrough=1' option.
> 
> Introduce the concept of identity domains to s390-iommu, which relies on
> the bus_dma_region to offset identity mappings to the start of the DMA
> aperture advertized by CLP.
> 
> Tested-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
> Reviewed-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
> Signed-off-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
> ---
>  drivers/iommu/s390-iommu.c | 95 +++++++++++++++++++++++++++++---------
>  1 file changed, 72 insertions(+), 23 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>

This may want to be changed to use

https://lore.kernel.org/linux-iommu/2-v1-91eed9c8014a+53a37-iommu_virtio_domains_jgg@xxxxxxxxxx/

Later on

Jason