[PATCH v2 19/21] mm: memcontrol: fix cannot alloc the maximum memcg ID

[Muchun Song]

The idr_alloc() does not include @max ID. So in the current implementation,
the maximum memcg ID is 65534 instead of 65535. It seems a bug. So fix this.

Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
 mm/memcontrol.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ae3ad1001824..a1c8ec858593 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5044,7 +5044,7 @@ static struct mem_cgroup *mem_cgroup_alloc(void)
 		return ERR_PTR(error);
 
 	memcg->id.id = idr_alloc(&mem_cgroup_idr, NULL,
-				 1, MEM_CGROUP_ID_MAX,
+				 1, MEM_CGROUP_ID_MAX + 1,
 				 GFP_KERNEL);
 	if (memcg->id.id < 0) {
 		error = memcg->id.id;
-- 
2.11.0