Comment 34 for bug 1776563

Hi Richard:

This issue should be related to the buggy BIOS ivrs table.
Kernel panic when found no southbridge device ID.

Could you try boot kernel with "amd_iommu_dump=1 amd_iommu=off" (remove other kernel parameters you tried to solve this issue).

If it works, please attach the dmesg here.
I will try to make a kernel patch to make kernel boot with irq map disabled instead of panic.