kasan: fix memory hotplug during boot

commit 3f1959721558a976aaf9c2024d5bc884e6411bf7 upstream.

Using module_init() is wrong.  E.g.  ACPI adds and onlines memory before
our memory notifier gets registered.

This makes sure that ACPI memory detected during boot up will not result
in a kernel crash.

Easily reproducible with QEMU, just specify a DIMM when starting up.

Link: http://lkml.kernel.org/r/20180522100756.18478-3-david@redhat.com
Fixes: 786a8959912e ("kasan: disable memory hotplug")
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c
index bb44af48587f0cb2a1b501b73fb968a06c7a6174..d90f29a166d89e8d6182ff84ea44451ff64a9fb3 100644 (file)
--- a/mm/kasan/kasan.c
+++ b/mm/kasan/kasan.c
@@ -843,5 +843,5 @@ static int __init kasan_memhotplug_init(void)
        return 0;
 }
 
-module_init(kasan_memhotplug_init);
+core_initcall(kasan_memhotplug_init);
 #endif