Messages in this thread | | | Subject | Re: [PATCH v12 3/5] iommu/vt-d: Add support for IOMMU default DMA mode build options | From | Robin Murphy <> | Date | Tue, 15 Jun 2021 09:25:10 +0100 |
| |
On 2021-06-15 08:26, Lu Baolu wrote: > Hi John, > > On 6/14/21 4:03 PM, John Garry wrote: >> On 12/06/2021 03:14, Lu Baolu wrote: >>> On 2021/6/11 20:20, John Garry wrote: >>>> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig >>>> index 2a71347611d4..4467353f981b 100644 >>>> --- a/drivers/iommu/Kconfig >>>> +++ b/drivers/iommu/Kconfig >>>> @@ -94,6 +94,7 @@ choice >>>> prompt "IOMMU default DMA mode" >>>> depends on IOMMU_DMA >>>> + default IOMMU_DEFAULT_LAZY if INTEL_IOMMU >>>> default IOMMU_DEFAULT_STRICT >>> >>> If two default values are different. Which one will be overridden? >> >> If I understand your question correctly, I think you are asking if >> both are set: >> CONFIG_IOMMU_DEFAULT_LAZY=y >> CONFIG_IOMMU_DEFAULT_STRICT=y >> >> If this happens, then make defconfig complains about both being set, >> and selects the 2nd, whatever that is. > > On x86, Intel or AMD, this will be > > prompt "IOMMU default DMA mode" > depends on IOMMU_DMA > default IOMMU_DEFAULT_LAZY > default IOMMU_DEFAULT_STRICT > > which will be default, LAZY or STRICT? Will it cause complains?
See Documentation/kbuild/kconfig-language.rst:
A config option can have any number of default values. If multiple default values are visible, only the first defined one is active.
Robin.
| |