Hi

After updating to 6.12.85 in Debian we got a regression report, where
frequently a user had "AMD-Vi: Completion-Wait loop timed out" logged.
The report is at: https://bugs.debian.org/1135313

While investigating it looks d2a0cac10597 ("iommu/amd: move
wait_on_sem() out of spinlock") got backported to 6.12.y but a
followup for it not.

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1135313#43 confirmed
that a backport of 9e249c484128 solved the problem. Now that one does
not apply cleanly. As an alternative the following two might work, the
first is a clean cherry-pick, the second on top needed a slight
adjustment since in 6.12.y f32fe7cb0198 is not present.

it would be though ideal if the maintainers can confirm this is the
way to go.

Regards,
Salvatore