path: root/lib
diff options
authorMarcin Slusarz <>2011-05-28 13:23:42 +0200
committerThomas Gleixner <>2011-06-20 14:38:43 +0200
commit161b6ae0e067e421b20bb35caf66bdb405c929ac (patch)
treeef8d7eb7d8b9acdfb6c6df40df771c6978d03132 /lib
parentf8b7fc6b514f34a51875dd48dff70d4d17a54f38 (diff)
debugobjects: Fix boot crash when kmemleak and debugobjects enabled
Order of initialization look like this: ... debugobjects kmemleak ...(lots of other subsystems)... workqueues (through early initcall) ... debugobjects use schedule_work for batch freeing of its data and kmemleak heavily use debugobjects, so when it comes to freeing and workqueues were not initialized yet, kernel crashes: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff810854d1>] __queue_work+0x29/0x41a [<ffffffff81085910>] queue_work_on+0x16/0x1d [<ffffffff81085abc>] queue_work+0x29/0x55 [<ffffffff81085afb>] schedule_work+0x13/0x15 [<ffffffff81242de1>] free_object+0x90/0x95 [<ffffffff81242f6d>] debug_check_no_obj_freed+0x187/0x1d3 [<ffffffff814b6504>] ? _raw_spin_unlock_irqrestore+0x30/0x4d [<ffffffff8110bd14>] ? free_object_rcu+0x68/0x6d [<ffffffff8110890c>] kmem_cache_free+0x64/0x12c [<ffffffff8110bd14>] free_object_rcu+0x68/0x6d [<ffffffff810b58bc>] __rcu_process_callbacks+0x1b6/0x2d9 ... because system_wq is NULL. Fix it by checking if workqueues susbystem was initialized before using. Signed-off-by: Marcin Slusarz <> Cc: Catalin Marinas <> Cc: Tejun Heo <> Cc: Dipankar Sarma <> Cc: Paul E. McKenney <> Cc: Link: Signed-off-by: Thomas Gleixner <>
Diffstat (limited to 'lib')
1 files changed, 1 insertions, 1 deletions
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 9d86e45086f5..a78b7c6e042c 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -198,7 +198,7 @@ static void free_object(struct debug_obj *obj)
* initialized:
if (obj_pool_free > ODEBUG_POOL_SIZE && obj_cache)
- sched = !work_pending(&debug_obj_work);
+ sched = keventd_up() && !work_pending(&debug_obj_work);
hlist_add_head(&obj->node, &obj_pool);