On 2021-03-03 17:36, Shameer Kolothum wrote:
The device iommu probe/attach might have failed leaving dev->iommu to NULL and device drivers may still invoke these functions resulting in a crash in iommu vendor driver code.
Hence make sure we check that.
Reviewed-by: Robin Murphy robin.murphy@arm.com
Fixes: a3a195929d40 ("iommu: Add APIs for multiple domains per device") Signed-off-by: Shameer Kolothum shameerali.kolothum.thodi@huawei.com
v2 --> v3 -Removed iommu_ops from struct dev_iommu. v1 --> v2: -Added iommu_ops to struct dev_iommu based on the discussion with Robin.
-Rebased against iommu-tree core branch.
drivers/iommu/iommu.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index d0b0a15dba84..e10cfa99057c 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2878,10 +2878,12 @@ EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids); */ int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features feat) {
- const struct iommu_ops *ops = dev->bus->iommu_ops;
- if (dev->iommu && dev->iommu->iommu_dev) {
const struct iommu_ops *ops = dev->iommu->iommu_dev->ops;
- if (ops && ops->dev_enable_feat)
return ops->dev_enable_feat(dev, feat);
if (ops->dev_enable_feat)return ops->dev_enable_feat(dev, feat);}
return -ENODEV; }
@@ -2894,10 +2896,12 @@ EXPORT_SYMBOL_GPL(iommu_dev_enable_feature); */ int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features feat) {
- const struct iommu_ops *ops = dev->bus->iommu_ops;
- if (dev->iommu && dev->iommu->iommu_dev) {
const struct iommu_ops *ops = dev->iommu->iommu_dev->ops;
- if (ops && ops->dev_disable_feat)
return ops->dev_disable_feat(dev, feat);
if (ops->dev_disable_feat)return ops->dev_disable_feat(dev, feat);}
return -EBUSY; }
@@ -2905,10 +2909,12 @@ EXPORT_SYMBOL_GPL(iommu_dev_disable_feature);
bool iommu_dev_feature_enabled(struct device *dev, enum iommu_dev_features feat) {
- const struct iommu_ops *ops = dev->bus->iommu_ops;
- if (dev->iommu && dev->iommu->iommu_dev) {
const struct iommu_ops *ops = dev->iommu->iommu_dev->ops;
- if (ops && ops->dev_feat_enabled)
return ops->dev_feat_enabled(dev, feat);
if (ops->dev_feat_enabled)return ops->dev_feat_enabled(dev, feat);}
return false; }