Fix potential endless loop in kswapd when compaction is not enabled
We should only test compaction_suitable if the kernel is built with
CONFIG_COMPACTION, otherwise the stub compaction_suitable function will
always return COMPACT_SKIPPED and send kswapd into an infinite loop.
Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 7658fd6..33c332b 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2946,7 +2946,8 @@
continue;
/* Would compaction fail due to lack of free memory? */
- if (compaction_suitable(zone, order) == COMPACT_SKIPPED)
+ if (COMPACTION_BUILD &&
+ compaction_suitable(zone, order) == COMPACT_SKIPPED)
goto loop_again;
/* Confirm the zone is balanced for order-0 */