Re: [PATCH rc] iommu: Allow ops->default_domain to work when !CONFIG_IOMMU_DMA

[Joerg Roedel <jroedel@suse.de>]

On Tue, Jan 30, 2024 at 12:12:53PM -0400, Jason Gunthorpe wrote:
> The ops->default_domain flow used a 0 req_type to select the default
> domain and this was enforced by iommu_group_alloc_default_domain().
> 
> When !CONFIG_IOMMU_DMA started forcing the old ARM32 drivers into IDENTITY
> it also overroad the 0 req_type of the ops->default_domain drivers to
> IDENTITY which ends up causing failures during device probe.
> 
> Make iommu_group_alloc_default_domain() accept a req_type that matches the
> ops->default_domain and have iommu_group_alloc_default_domain() generate a
> req_type that matches the default_domain.
> 
> This way the req_type always describes what kind of domain should be
> attached and ops->default_domain overrides all other mechanisms to choose
> the default domain.
> 
> Fixes: 2ad56efa80db ("powerpc/iommu: Setup a default domain and remove set_platform_dma_ops")
> Fixes: 0f6a90436a57 ("iommu: Do not use IOMMU_DOMAIN_DMA if CONFIG_IOMMU_DMA is not enabled")
> Reported-by: Ovidiu Panait <ovidiu.panait@windriver.com>
> Closes: https://lore.kernel.org/linux-iommu/20240123165829.630276-1-ovidiu.panait@windriver.com/
> Reported-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
> Closes: https://lore.kernel.org/linux-iommu/170618452753.3805.4425669653666211728.stgit@ltcd48-lp2.aus.stglab.ibm.com/
> Tested-by: Ovidiu Panait <ovidiu.panait@windriver.com>
> Tested-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> ---
>  drivers/iommu/iommu.c | 18 +++++++++++++-----
>  1 file changed, 13 insertions(+), 5 deletions(-)

Applied, thanks.

-- 
Jörg Rödel
jroedel@suse.de

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