PM / Hibernate / Memory hotplug: Always use for_each_populated_zone()
Use for_each_populated_zone() instead of for_each_zone() in hibernation
code. This fixes a bug on s390, where we allow both config options
HIBERNATION and MEMORY_HOTPLUG, so that we also have a ZONE_MOVABLE
here. We only allow hibernation if no memory hotplug operation was
performed, so in fact both features can only be used exclusively, but
this way we don't need 2 differently configured (distribution) kernels.
If we have an unpopulated ZONE_MOVABLE, we allow hibernation but run
into a BUG_ON() in memory_bm_test/set/clear_bit() because hibernation
code iterates through all zones, not only the populated zones, in
several places. For example, swsusp_free() does for_each_zone() and
then checks for pfn_valid(), which is true even if the zone is not
populated, resulting in a BUG_ON() later because the pfn cannot be
found in the memory bitmap.
Replacing all occurences of for_each_zone() in hibernation code with
for_each_populated_zone() would fix this issue.
[rjw: Rebased on top of linux-next hibernation patches.]
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 0a06b11..bf06658 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -853,7 +853,7 @@
struct zone *zone;
unsigned int n = 0;
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
unsigned long pfn, max_zone_pfn;
if (!is_highmem(zone))
@@ -916,7 +916,7 @@
unsigned long pfn, max_zone_pfn;
unsigned int n = 0;
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
if (is_highmem(zone))
continue;
@@ -1010,7 +1010,7 @@
struct zone *zone;
unsigned long pfn;
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
unsigned long max_zone_pfn;
mark_free_pages(zone);
@@ -1065,7 +1065,7 @@
struct zone *zone;
unsigned long pfn, max_zone_pfn;
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
if (pfn_valid(pfn)) {
@@ -1397,7 +1397,7 @@
struct zone *zone;
unsigned int free = alloc_normal;
- for_each_zone(zone)
+ for_each_populated_zone(zone)
if (!is_highmem(zone))
free += zone_page_state(zone, NR_FREE_PAGES);
@@ -1688,7 +1688,7 @@
unsigned long pfn, max_zone_pfn;
/* Clear page flags */
- for_each_zone(zone) {
+ for_each_populated_zone(zone) {
max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
if (pfn_valid(pfn))