Re: [PATCH] memory hotplug disable boot option

Dave Hansen
2010-06-29T00:04:32Z

On Mon, 2010-06-28 at 08:44 -0700, Greg KH wrote:
> > The directories being created are the standard directories, one for each of the memory
> > sections present at boot. I think the most used files in each of these directories
> > is the state and removable file used to do memory hotplug.
>
> And perhaps we shouldn't really be creating so many directories? Why
> not work with the memory hotplug developers to change their interface to
> not abuse sysfs in such a manner?

Heh, it wasn't abuse until we got this much memory. But, I think this
one is pretty much 100% my fault.

Nathan, I think the right fix here is probably to untie sysfs from the
sections a bit. We should be able to have sysfs dirs that represent
more than one contiguous SECTION_SIZE area of memory.

It will mean re-teaching some of the tools how things work. They'll
have to know that you can split mem sections, and we'll have to come up
with a way to do the splitting.

Does ppc *really* remove 16MB sections of RAM these days? It's probably
worth checking with the firmware folks to see what the limits are in
practice.

-- Dave