Description:
Intel implementation of IOMMU (VT-D) doesn't work on newest kernels with IEEE1964 (Firewire) enabled in BIOS.
Probably this bug is kernel-specific, but i didn't find any strict info anywhere and i don't know if it is distribution specific or not.

Kernel keeps spamming following error message and doesn't boot (i am not sure with this messages exactly, it spams very fast):
DRHD: handling fault status reg 3
DMAR:[DMA Read] Request device [0b:00.1] fault addr fff00000
DMAR:[fault reason 02] Present bit in context entry is clear

Additional info:
System fully updated at 08-02-2012 releases
Kernel 3.4.7-1-ARCH
Fully VT-X & VT-D virtualization enabled CPU & Mainboard
Similar (but not the same) bug at https://bugzilla.redhat.com/show_bug.cgi?id=490477

Steps to reproduce:
Turn in BIOS VT-D on
Turn in BIOS I/O Firewire on
Add kernel boot parameter intel_iommu=on into /boot/grub/{menu.lst|grub.cfg}
Boot

Partial solution:
Turn of firewire