Re: [PATCH v3] iommu/vt-d: Disable IOMMU by default on Lenovo ThinkPad P50s

[Oliver Lin]

On 27/7/2026 09:31, Tian, Kevin wrote:
> This needs an official erratum disclosure from the vendor...
Thanks for the clarification.

Could you please advise whether this issue should be treated as an Intel 
VT-d erratum or a Lenovo firmware issue?

The symptom is:
- ThinkPad P50s with VT-d enabled cannot fully power off.
- Adding intel_iommu=off resolves the issue.
- The issue is reproducible on this platform.

If Intel erratum is not applicable, would a Lenovo firmware confirmation 
be sufficient for adding a platform quirk?