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> + if (!amd_iommu_disabled || amd_iommu_force_enable) { You should not need to check the amd_iommu_force_enable since it is used only to skip a workaround logic within the same function. You can simply just do if (!amd_iommu_disabled) /* Make sure ACS will be enabled during PCI probe */ pci_request_acs(); With that Reviewed-by: Suravee Suthikulpanit Thanks, Suravee > + /* Make sure ACS will be enabled during PCI probe */ > + pci_request_acs(); > + } > > return true; > }