Re: [PATCH 1/6] mm/page_alloc: fix same zone check in __pageblock_pfn_to_page()

From: Mel Gorman
Date: Mon Mar 21 2016 - 07:37:38 EST

On Mon, Mar 14, 2016 at 04:31:32PM +0900, js1304@xxxxxxxxx wrote:
> From: Joonsoo Kim <>
> There is a system that node's pfn are overlapped like as following.
> -----pfn-------->
> N0 N1 N2 N0 N1 N2
> Therefore, we need to care this overlapping when iterating pfn range.
> In __pageblock_pfn_to_page(), there is a check for this but it's
> not sufficient. This check cannot distinguish the case that zone id
> is the same but node id is different. This patch fixes it.

I think you may be mixing up page_zone_id with page_zonenum.

Mel Gorman