Public bug reported:

A future BIOS upgrade may occur for Strix, Krackan, Strix Halo, and
Gorgon Point systems that has the potential to break s0i3 on Ubuntu.
OEMs may choose to roll this out.

This BIOS upgrade modifies the ACPI IVRS UID entry for a device from a
numeric value "1" to a string value "_SB.MHSP". The upgrade however DOES
NOT modify the matching SSDT entry, that one remains "1".

In the current AMD Linux IOMMU driver this causes the device not to be
configured by the IOMMU. Suspending the system when this device is not
configured by the IOMMU will cause an unrecoverable page fault.

This mismatch however is intentional from the BIOS team and stems from
how the IOMMU spec is interpreted by Microsoft vs from AMD Linux IOMMU
driver. For this reason; it's going to be important to allow this to
work from Linux as well.

https://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux.git/commit/?h=next&id=51c33f333bbf7bdb6aa2a327e3a3e4bbb2591511

** Affects: hwe-next
     Importance: Undecided
         Status: New

** Affects: linux (Ubuntu)
     Importance: Undecided
         Status: New

** Affects: linux-oem-6.11 (Ubuntu)
     Importance: Undecided
         Status: New

** Affects: linux-oem-6.14 (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: amd oem-priority originate-from-2110051

** Tags added: amd oem-priority originate-from-2110051

** Also affects: linux-oem-6.11 (Ubuntu)
   Importance: Undecided
       Status: New

** Also affects: linux (Ubuntu)
   Importance: Undecided
       Status: New

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https://bugs.launchpad.net/bugs/2115174

Title:
  Handle IOMMU IVRS entries with mismatched UID on AMD Strix or newer
  platforms

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