Changing kernel API / Breaking VirtualBox - update criteria violation?

[Michal Schmidt]

On 11/21/2011 09:32 PM, Till Maas wrote:
> a recent kernel update[0] broke Fedora's ability to be a VirtualBox
> host, because asm/amd_iommu.h was removed.

This is a part of the in-kernel API, not the kernel<->userspace 
interface. The internal API can change at any time.

External kernel modules can break whenever the kernel is updated for the 
smallest bugfix.

http://lxr.linux.no/#linux+v3.1.2/Documentation/stable_api_nonsense.txt

Michal