Re: [PATCH] i386: single node SPARSEMEM fix

Magnus Damm
2005-09-08T01:54:08Z

On 9/8/05, Andrew Morton <akpm@osdl.org> wrote:
> "Martin J. Bligh" <mbligh@mbligh.org> wrote:
> >
> >
> >
> > --On Wednesday, September 07, 2005 11:27:54 -0700 Dave Hansen <haveblue@us.ibm.com> wrote:
> >
> > > On Wed, 2005-09-07 at 11:22 -0700, Martin J. Bligh wrote:
> > >> CONFIG_NUMA was meant to (and did at one point) support both NUMA and flat
> > >> machines. This is essential in order for the distros to support it - same
> > >> will go for sparsemem.
> > >
> > > That's a different issue. The current code works if you boot a NUMA=y
> > > SPARSEMEM=y machine with a single node. The current Kconfig options
> > > also enforce that SPARSEMEM depends on NUMA on i386.
> > >
> > > Magnus would like to enable SPARSEMEM=y while CONFIG_NUMA=n. That
> > > requires some Kconfig changes, as well as an extra memory present call.
> > > I'm questioning why we need to do that when we could never do
> > > DISCONTIG=y while NUMA=n on i386.
> >
> > Ah, OK - makes more sense. However, some machines do have large holes
> > in e820 map setups - is not really critical, more of an efficiency
> > thing.
>
> Confused. Does all this mean that we want the patch, or not?

What about if I remove the Kconfig stuff and just keep the "fix" for
the non-NUMA version of setup_memory()?

/ magnus