Re: [bug report]: iommu WARNING is observed on powerpc system during pci enumeration at boot up

Nicolin Chen
2026-03-09T18:49:18Z

On Mon, Mar 09, 2026 at 11:27:42PM +0530, Nilay Shroff wrote:
> Looking at the warning it seems that this is a regression caused due to
> commit a75b2be249d6 ("iommu: Add iommu_driver_get_domain_for_dev() helper").
>
> Any help from the iommu expert would be appreciated. Though I am not expert,
> it seems the following patch help fix this warning (I encourage the iommu
> developers to confirm and/or take this forward) :
>
> diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
> index 0ce71310b7d9..d122e8447831 100644
> --- a/arch/powerpc/kernel/iommu.c
> +++ b/arch/powerpc/kernel/iommu.c
> @@ -1159,7 +1159,7 @@ spapr_tce_platform_iommu_attach_dev(struct iommu_domain *platform_domain,
> struct device *dev,
> struct iommu_domain *old)
> {
> - struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
> + struct iommu_domain *domain = iommu_driver_get_domain_for_dev(dev);
> struct iommu_table_group *table_group;
> struct iommu_group *grp;
>
>
> Please let me know if any further information is needed.

Yea, that should be the fix.

Please submit a "PATCH rc" with:

Fixes: a75b2be249d6 ("iommu: Add iommu_driver_get_domain_for_dev() helper")
Cc: stable@vger.kernel.org

Thanks!
Nicolin