From: Tony Lindgren <tony@xxxxxxxxxxx> [ Upstream commit 71ff461c3f41f6465434b9e980c01782763e7ad8 ] Commit 3f6634d997db ("iommu: Use right way to retrieve iommu_ops") started triggering a NULL pointer dereference for some omap variants: __iommu_probe_device from probe_iommu_group+0x2c/0x38 probe_iommu_group from bus_for_each_dev+0x74/0xbc bus_for_each_dev from bus_iommu_probe+0x34/0x2e8 bus_iommu_probe from bus_set_iommu+0x80/0xc8 bus_set_iommu from omap_iommu_init+0x88/0xcc omap_iommu_init from do_one_initcall+0x44/0x24 This is caused by omap iommu probe returning 0 instead of ERR_PTR(-ENODEV) as noted by Jason Gunthorpe <jgg@xxxxxxxx>. Looks like the regression already happened with an earlier commit 6785eb9105e3 ("iommu/omap: Convert to probe/release_device() call-backs") that changed the function return type and missed converting one place. Cc: Drew Fustini <dfustini@xxxxxxxxxxxx> Cc: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Cc: Suman Anna <s-anna@xxxxxx> Suggested-by: Jason Gunthorpe <jgg@xxxxxxxx> Fixes: 6785eb9105e3 ("iommu/omap: Convert to probe/release_device() call-backs") Fixes: 3f6634d997db ("iommu: Use right way to retrieve iommu_ops") Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> Tested-by: Drew Fustini <dfustini@xxxxxxxxxxxx> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220331062301.24269-1-tony@xxxxxxxxxxx Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/iommu/omap-iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c index 91749654fd49..be60f6f3a265 100644 --- a/drivers/iommu/omap-iommu.c +++ b/drivers/iommu/omap-iommu.c @@ -1661,7 +1661,7 @@ static struct iommu_device *omap_iommu_probe_device(struct device *dev) num_iommus = of_property_count_elems_of_size(dev->of_node, "iommus", sizeof(phandle)); if (num_iommus < 0) - return 0; + return ERR_PTR(-ENODEV); arch_data = kcalloc(num_iommus + 1, sizeof(*arch_data), GFP_KERNEL); if (!arch_data) -- 2.35.1