Subject: [PATCH] [BZ 156627] chmem: try to online memory to zone movable
From: Gerald Schaefer <gerald.schaefer@de.ibm.com>

Description:  chmem: try to online memory to zone movable
Symptom:      Standby/reserved memory that is onlined with chmem will be set
              online to zone normal, instead of zone movable, and so it is much
              less likely to be able to be offlined again.
Problem:      With recent kernels, the default zone for hotplug memory was
              changed from zone movable to zone normal.
Solution:     Let chmem first try to online memory to the zone movable, before
              setting it online to the default zone.
Reproduction: Set standby/reserved memory online with chmem, and check
              /proc/zoneinfo for zone allocation.
Upstream-ID:  -
Problem-ID:   156627

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
---
 zconf/chmem |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/zconf/chmem
+++ b/zconf/chmem
@@ -86,7 +86,10 @@ sub chmem_online($)
 {
 	my $block = shift;
 
-	qx(echo online > $memdir/memory$block/state 2>/dev/null);
+	qx(echo online_movable > $memdir/memory$block/state 2>/dev/null);
+	if ($? >> 8 != 0) {
+		qx(echo online > $memdir/memory$block/state 2>/dev/null);
+	}
 	return $? >> 8;
 }