| From 3e6b11df245180949938734bc192eaf32f3a06b3 Mon Sep 17 00:00:00 2001 |
| From: Andrey Vagin <avagin@openvz.org> |
| Date: Tue, 13 Aug 2013 16:00:47 -0700 |
| Subject: memcg: don't initialize kmem-cache destroying work for root caches |
| |
| From: Andrey Vagin <avagin@openvz.org> |
| |
| commit 3e6b11df245180949938734bc192eaf32f3a06b3 upstream. |
| |
| struct memcg_cache_params has a union. Different parts of this union |
| are used for root and non-root caches. A part with destroying work is |
| used only for non-root caches. |
| |
| I fixed the same problem in another place v3.9-rc1-16204-gf101a94, but |
| didn't notice this one. |
| |
| This patch fixes the kernel panic: |
| |
| [ 46.848187] BUG: unable to handle kernel paging request at 000000fffffffeb8 |
| [ 46.849026] IP: [<ffffffff811a484c>] kmem_cache_destroy_memcg_children+0x6c/0xc0 |
| [ 46.849092] PGD 0 |
| [ 46.849092] Oops: 0000 [#1] SMP |
| ... |
| |
| Signed-off-by: Andrey Vagin <avagin@openvz.org> |
| Cc: Glauber Costa <glommer@openvz.org> |
| Cc: Johannes Weiner <hannes@cmpxchg.org> |
| Acked-by: Michal Hocko <mhocko@suse.cz> |
| Cc: Balbir Singh <bsingharora@gmail.com> |
| Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> |
| Cc: Konstantin Khlebnikov <khlebnikov@openvz.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> |
| |
| --- |
| mm/memcontrol.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/mm/memcontrol.c |
| +++ b/mm/memcontrol.c |
| @@ -3186,11 +3186,11 @@ int memcg_register_cache(struct mem_cgro |
| if (!s->memcg_params) |
| return -ENOMEM; |
| |
| - INIT_WORK(&s->memcg_params->destroy, |
| - kmem_cache_destroy_work_func); |
| if (memcg) { |
| s->memcg_params->memcg = memcg; |
| s->memcg_params->root_cache = root_cache; |
| + INIT_WORK(&s->memcg_params->destroy, |
| + kmem_cache_destroy_work_func); |
| } else |
| s->memcg_params->is_root_cache = true; |
| |