Re: [PATCH v3 2/2] iommupt: Avoid rewalking during map

[Jason Gunthorpe <jgg@nvidia.com>]

On Sat, May 09, 2026 at 05:41:02PM +0000, Josua Mayer wrote:
> This patch has landed in v7.1-rc1 and introduced a regression on the
> arm64 SolidRun LX2160A Clearfog-CX board.
> 
> Since d6c65b0fd621 ("iommupt: Avoid rewalking during map"),
> boot now stalls - printing many smmu errors.
> 
> Please find attached full boot logs for reference:
> 
> - good.txt @ 99fb8afa16ad
> - bad.txt @ d6c65b0fd621
> - config.txt: .config from the build
> 
> Is there any advice how to deal with this?

Does this help?

--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -2669,7 +2669,7 @@ int iommu_map_nosync(struct iommu_domain *domain, unsigned long iova,
                return 0;
        }
        ret = __iommu_map_domain_pgtbl(domain, iova, paddr, size, prot, gfp);
-       if (!ret)
+       if (ret)
                return ret;
 
        trace_map(iova, paddr, size);

Although it would be surprising your system triggers a ret!=0 while
booting successfully, that could by why it wasn't noticed in any
testing so far..

Jason