iommu/mediatek: Use correct fwspec in mtk_iommu_add_device()

joergroedel · joergroedel · commit da5d2748e4a4 · 2019-01-23T13:51:05.000+01:00
The mtk_iommu_add_device() function keeps the fwspec in an on-stack pointer and calls mtk_iommu_create_mapping(), which might change its source, dev->iommu_fwspec. This causes the on-stack pointer to be obsoleted and the device initialization to fail. Update the on-stack fwspec pointer after mtk_iommu_create_mapping() has been called. Reported-by: Frank Wunderlich <frank-w@public-files.de> Fixes: a9bf2ee ('iommu/mediatek: Use helper functions to access dev->iommu_fwspec') Tested-by: Frank Wunderlich <frank-w@public-files.de> Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c
@@ -442,6 +442,10 @@ static int mtk_iommu_add_device(struct device *dev)
 		iommu_spec.args_count = count;
 
 		mtk_iommu_create_mapping(dev, &iommu_spec);
+
+		/* dev->iommu_fwspec might have changed */
+		fwspec = dev_iommu_fwspec_get(dev);
+
 		of_node_put(iommu_spec.np);
 	}
 

Original file line number	Diff line number	Diff line change
`@@ -442,6 +442,10 @@ static int mtk_iommu_add_device(struct device *dev)`
`442`	`442`	`iommu_spec.args_count = count;`
`443`	`443`
`444`	`444`	`mtk_iommu_create_mapping(dev, &iommu_spec);`
	`445`	`+`
	`446`	`+ /* dev->iommu_fwspec might have changed */`
	`447`	`+ fwspec = dev_iommu_fwspec_get(dev);`
	`448`	`+`
`445`	`449`	`of_node_put(iommu_spec.np);`
`446`	`450`	`}`
`447`	`451`