[PATCH] mm: memcontrol: Fix do not put the css reference

[Muchun Song]

We should put the css reference when memory allocation failed.

Fixes: f0a3a24b532d ("mm: memcg/slab: rework non-root kmem_cache lifecycle 
management")
Signed-off-by: Muchun Song <songmuc...@bytedance.com>
---
 mm/memcontrol.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 0b38b6ad547d..2323d811ee8e 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2772,8 +2772,10 @@ static void memcg_schedule_kmem_cache_create(struct 
mem_cgroup *memcg,
                return;
 
        cw = kmalloc(sizeof(*cw), GFP_NOWAIT | __GFP_NOWARN);
-       if (!cw)
+       if (!cw) {
+               css_put(&memcg->css);
                return;
+       }
 
        cw->memcg = memcg;
        cw->cachep = cachep;
-- 
2.11.0