diff options
| author | Glauber Costa <glommer@parallels.com> | 2013-02-12 13:46:22 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-12 14:34:00 -0800 |
| commit | 4ba902b5741859a04fdb90d675b9a87721a3fd59 (patch) | |
| tree | 7999ced371d2372635567fba4028610cfd5ae7e5 /mm/memcontrol.c | |
| parent | 9977f0f164d46613288e0b5778eae500dfe06f31 (diff) | |
| download | linux-4ba902b5741859a04fdb90d675b9a87721a3fd59.tar.bz2 | |
memcg: fix kmemcg registration for late caches
The designed workflow for the caches in kmemcg is: register it with
memcg_register_cache() if kmemcg is already available or later on when a
new kmemcg appears at memcg_update_cache_sizes() which will handle all
caches in the system. The caches created at boot time will be handled
by the later, and the memcg-caches as well as any system caches that are
registered later on by the former.
There is a bug, however, in memcg_register_cache: we correctly set up
the array size, but do not mark the cache as a root cache.
This means that allocations for any cache appearing late in the game
will see memcg->memcg_params->is_root_cache == false, and in particular,
trigger VM_BUG_ON(!cachep->memcg_params->is_root_cache) in
__memcg_kmem_cache_get.
The obvious fix is to include the missing assignment.
Signed-off-by: Glauber Costa <glommer@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 09255ec8159c..fbb60b103e64 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3030,7 +3030,9 @@ int memcg_register_cache(struct mem_cgroup *memcg, struct kmem_cache *s, if (memcg) { s->memcg_params->memcg = memcg; s->memcg_params->root_cache = root_cache; - } + } else + s->memcg_params->is_root_cache = true; + return 0; } |