Linux supports overriding your computer ACPI tables by adding updated tables to the initrd. Checkout your local documentation at the linux tree at Documentation/admin-guide/acpi/initrd_table_override.rst.

I just uploaded to Debian a small initramfs-tools hook to add tables found at /var/lib/acpi-override/ to the initrd. For now, it's all that it does. The users have to modify the tables themselves and drop them at the referred directory.

It should be on the NEW queue and out to unstable after some time, and it's maintained at salsa.

My usecase for this is a small change to the DMAR table of my Libreboot-enabled X200, so I can experiment with IOMMU on it.

As future work, I may consider a tool to help at least update the OEM revision of the tables, to make it less error-prone to users to update them.

I hope this is useful to other people.