Re: [PATCH] SPARSEMEM + NUMA can't handle unaligned memory regions?

[Andy Whitcroft <apw@shadowen.org>]

Dave Hansen wrote:
> On Tue, 2006-05-09 at 15:28 +0100, Andy Whitcroft wrote:		
> 
>>+/*
>>+ * During early boot we need to record the nid from which we will
>>+ * later allocate the section mem_map.  Encode this into the section
>>+ * pointer.  Overload the section_mem_map with this information.
>>+ */ 
> 
> 
> Andy, this all looks pretty good.  Although, it might be nice to
> document this a bit more. 
> 
> First, can you update the mem_section definition comment?  It has a nice
> explanation of how we use section_mem_map, and it would be a shame to
> miss this use.
> 
> Also, your comment says when we _record_ the nid information, but not
> that it is only _used_ during early boot.  I think this is what Mike K.
> missed, and it might be good to clarify.
> 
> How about something like this:
> 
> /*
>  * During early boot, before section_mem_map is used for an actual
>  * mem_map, we use section_mem_map to store the section's NUMA
>  * node.  This keeps us from having to use another data structure.  The
>  * node information is cleared just before we store the real mem_map.
>  */

Yep sounds very sane.  Will update and resend -- best wait and see if it
fixes Michael find its works for him too :).

Thanks.

-apw