From 3fd7e3ce7ec2dcf13a2fa592ee48dd528ba9c561 Mon Sep 17 00:00:00 2001
From: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Date: Thu, 6 Nov 2008 12:53:36 -0800
Subject: [PATCH] memory hotplug: fix page_zone() calculation in
 test_pages_isolated()

commit a70dcb969f64e2fa98c24f47854f20bf02ff0092 upstream.

My last bugfix here (adding zone->lock) introduced a new problem: Using
page_zone(pfn_to_page(pfn)) to get the zone after the for() loop is wrong.
 pfn will then be >= end_pfn, which may be in a different zone or not
present at all.  This may lead to an addressing exception in page_zone()
or spin_lock_irqsave().

Now I use __first_valid_page() again after the loop to find a valid page
for page_zone().

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Acked-by: Nathan Fontenot <nfont@austin.ibm.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
Reading git-format-patch failed