mm/page_alloc.c: skip ZONE_MOVABLE if required_kernelcore is larger than totalpages

If kernelcore was not specified, or the kernelcore size is zero
(required_movablecore >= totalpages), or the kernelcore size is larger
than totalpages, there is no ZONE_MOVABLE.  We should fill the zone with
both kernel memory and movable memory.

Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: <zhongjiang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 2 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 86f7d952e2cc..06e62300d627 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5675,8 +5675,11 @@ static void __init find_zone_movable_pfns_for_nodes(void)
                 required_kernelcore = max(required_kernelcore, corepages);
         }
 
-        /* If kernelcore was not specified, there is no ZONE_MOVABLE */
-        if (!required_kernelcore)
+        /*
+         * If kernelcore was not specified or kernelcore size is larger
+         * than totalpages, there is no ZONE_MOVABLE.
+         */
+        if (!required_kernelcore || required_kernelcore >= totalpages)
                 goto out;
 
         /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */