From: Robin Murphy robin.murphy@arm.com
mainline inclusion from mainline-v4.20-rc1 commit e8e683ae9a736407a20135df7809090a446db707 category:bugfix bugzilla:NA CVE:NA
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Whilst iommu_probe_device() does check for non-NULL ops as the previous code did, it does not do so in the same order relative to the other checks, and as a result means that -EPROBE_DEFER returned by of_xlate() (plus any real error condition too) gets overwritten with -EINVAL and leads to various misbehaviour.
Reinstate the original logic, but without implicitly relying on ops being set to infer !err as the initial condition (now that the validity of ops for its own sake is checked elsewhere).
Fixes: 641fb0efbff0 ("iommu/of: Don't call iommu_ops->add_device directly") Signed-off-by: Robin Murphy robin.murphy@arm.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Chen Jun chenjun102@huawei.com Reviewed-by: Hanjun Guo guohanjun@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/iommu/of_iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index 0d55a9594db1..dc0c69776863 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -218,7 +218,7 @@ const struct iommu_ops *of_iommu_configure(struct device *dev, * If we have reason to believe the IOMMU driver missed the initial * probe for dev, replay it to get things in order. */ - if (dev->bus && !device_iommu_mapped(dev)) + if (!err && dev->bus && !device_iommu_mapped(dev)) err = iommu_probe_device(dev);
/* Ignore all other errors apart from EPROBE_DEFER */