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> 1595 > 1596 list_for_each_entry(dev_data, &domain->dev_list, list) { > 1597 struct amd_iommu *iommu = rlookup_amd_iommu(dev_data->dev); <- > 1598 > 1599 set_dte_entry(iommu, dev_data); <- > 1600 clone_aliases(iommu, dev_data->dev); > 1601 } > 1602 > 1603 list_for_each_entry(dev_data, &domain->dev_list, list) > 1604 device_flush_dte(dev_data); > 1605 > 1606 domain_flush_complete(domain); > 1607 } > > The "rlookup_amd_iommu" function may return NULL, and the "set_dte_entry" function > will call "get_dev_table" which will dereference the NULL pointer. > > Is this an issue that may cause panic? Or will "rlookup_amd_iommu" function never > return NULL? During init driver will initialize rlookup_table. rlookup_amd_iommu will not return NULL. So its fine. -Vasant