kmemleak: Add support for memory hotplug

Ensure that memory hotplug can co-exist with kmemleak
by taking the hotplug lock before scanning the memory
banks.

Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 15c50302ff93..c833addd94d7 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -100,6 +100,7 @@
 
 #include <linux/kmemcheck.h>
 #include <linux/kmemleak.h>
+#include <linux/memory_hotplug.h>
 
 /*
  * Kmemleak configuration and common defines.
@@ -1292,9 +1293,9 @@ static void kmemleak_scan(void)
 #endif
 
         /*
-         * Struct page scanning for each node. The code below is not yet safe
-         * with MEMORY_HOTPLUG.
+         * Struct page scanning for each node.
          */
+        lock_memory_hotplug();
         for_each_online_node(i) {
                 pg_data_t *pgdat = NODE_DATA(i);
                 unsigned long start_pfn = pgdat->node_start_pfn;
@@ -1313,6 +1314,7 @@ static void kmemleak_scan(void)
                         scan_block(page, page + 1, NULL, 1);
                 }
         }
+        unlock_memory_hotplug();
 
         /*
          * Scanning the task stacks (may introduce false negatives).