Re: [git pull] m68k SLUB fix for 2.6.39

David Rientjes
2011-05-04T19:03:14Z

On Wed, 4 May 2011, Christoph Lameter wrote:

> As i have explained multiple times before: This is a generic issue with a
> kernel configuration that has DISCONTIGMEM on and NUMA configured off.
> Core code in various subsystems makes various assumptions in the !NUMA
> case. F.e. page_to_nid(page) == 0. Slub is one of them.
>

Agreed, but James is still reporting that there is a slub oops with at
least parisc even with the N_NORMAL_MEMORY fix applied. He's currently
retrying on a clean kernel with the latest git (and presumably
CONFIG_BROKEN to enable CONFIG_SLUB). If he reports that slub is no
longer an issue with such a configuration, then I agree that we can remove
the Kconfig change for slub so it no longer forces CONFIG_NUMA for
CONFIG_DISCONTIGMEM (or CONFIG_BROKEN).

If that's the case, and we'll have to wait for James' report back first,
then we can probably make adjustments in the per-arch Kconfigs that enable
discontigmem without NUMA and then make it a strict requirement (or
CONFIG_BROKEN) until the additional problems are solved in other places in
the kernel.