RE: [PATCH v2 1/1] iommu/vt-d: Assign devtlb cache tag on ATS enablement

[Tian, Kevin]

> From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Sent: Wednesday, June 25, 2025 1:02 PM
> 
> Commit <4f1492efb495> ("iommu/vt-d: Revert ATS timing change to fix boot
> failure") placed the enabling of ATS in the probe_finalize callback. This
> occurs after the default domain attachment, which is when the ATS cache
> tag is assigned. Consequently, the device TLB cache tag is missed when the
> domain is attached, leading to the device TLB not being invalidated in the
> iommu_unmap paths.
> 
> Fix this by assigning the CACHE_TAG_DEVTLB cache tag when ATS is enabled.
> 
> Fixes: 4f1492efb495 ("iommu/vt-d: Revert ATS timing change to fix boot
> failure")
> Cc: stable@xxxxxxxxxxxxxxx
> Suggested-by: Kevin Tian <kevin.tian@xxxxxxxxx>
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Tested-by: Shuicheng Lin <shuicheng.lin@xxxxxxxxx>

Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>