memory hotplug: fix page_zone() calculation in test_pages_isolated()
authorGerald Schaefer <gerald.schaefer@de.ibm.com>
Thu, 6 Nov 2008 20:53:36 +0000 (12:53 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 6 Nov 2008 23:41:19 +0000 (15:41 -0800)
commita70dcb969f64e2fa98c24f47854f20bf02ff0092
tree2224e321ba5d5455fd36ec2cf14f11ff97aa8931
parentc87591b719737b4e91eb1a9fa8fd55a4ff1886d6
memory hotplug: fix page_zone() calculation in test_pages_isolated()

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>
mm/page_isolation.c