This looks like an issue I've had related to the backdoor entry hack for
GART_IOMMU – Basically, amd64_agp doesn't utilise module_init or module_exit
when CONFIG_GART_IOMMU is enabled, instead stating:
drivers/char/agp/amd64-ag...@774-775:
/* On AMD64 the PCI driver needs to initialize this
When the agp driver is not compiled in but is build as module, the kernel oopes
on modprobing radeon with modeset=1.
Dec 7 22:08:53 datengrab kernel: BUG: unable to handle kernel NULL pointer
dereference at 0074
Dec 7 22:08:53 datengrab kernel: IP: [a01f693c]
