2024-01-30 06:25:03

by Tian, Kevin

[permalink] [raw]
Subject: RE: [PATCH v2 1/1] iommu/vt-d: Remove INTEL_IOMMU_BROKEN_GFX_WA

> From: Lu Baolu <[email protected]>
> Sent: Tuesday, January 30, 2024 2:08 PM
>
> Commit 62edf5dc4a524 ("intel-iommu: Restore DMAR_BROKEN_GFX_WA
> option for
> broken graphics drivers") was introduced 24 years ago as a temporary
> workaround for graphics drivers that used physical addresses for DMA and
> avoided DMA APIs. This workaround was disabled by default.
>
> As 24 years have passed, it is expected that graphics driver developers
> have migrated their drivers to use kernel DMA APIs. Therefore, this
> workaround is no longer required and could been removed.
>
> The Intel iommu driver also provides a "igfx_off" option to turn off
> the DAM translation for the graphic dedicated IOMMU. Hence, there is
> really no good reason to keep this config option.
>

s/DAM/DMA/


2024-01-30 06:39:19

by Baolu Lu

[permalink] [raw]
Subject: Re: [PATCH v2 1/1] iommu/vt-d: Remove INTEL_IOMMU_BROKEN_GFX_WA

On 2024/1/30 14:24, Tian, Kevin wrote:
>> From: Lu Baolu <[email protected]>
>> Sent: Tuesday, January 30, 2024 2:08 PM
>>
>> Commit 62edf5dc4a524 ("intel-iommu: Restore DMAR_BROKEN_GFX_WA
>> option for
>> broken graphics drivers") was introduced 24 years ago as a temporary
>> workaround for graphics drivers that used physical addresses for DMA and
>> avoided DMA APIs. This workaround was disabled by default.
>>
>> As 24 years have passed, it is expected that graphics driver developers
>> have migrated their drivers to use kernel DMA APIs. Therefore, this
>> workaround is no longer required and could been removed.
>>
>> The Intel iommu driver also provides a "igfx_off" option to turn off
>> the DAM translation for the graphic dedicated IOMMU. Hence, there is
>> really no good reason to keep this config option.
>>
>
> s/DAM/DMA/

Fixed. :-)

Best regards,
baolu