debugobjects: Make debug_object_activate() return status
In order to better respond to things like duplicate invocations
of call_rcu(), RCU needs to see the status of a call to
debug_object_activate(). This would allow RCU to leak the callback in
order to avoid adding freelist-reuse mischief to the duplicate invoations.
This commit therefore makes debug_object_activate() return status,
zero for success and -EINVAL for failure.
Signed-off-by: Paul E. McKenney <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Sedat Dilek <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Linus Torvalds <[email protected]>
Tested-by: Sedat Dilek <[email protected]>
Reviewed-by: Josh Triplett <[email protected]>
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 37061ed..bf2c8b1 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -381,19 +381,21 @@
* debug_object_activate - debug checks when an object is activated
* @addr: address of the object
* @descr: pointer to an object specific debug description structure
+ * Returns 0 for success, -EINVAL for check failed.
*/
-void debug_object_activate(void *addr, struct debug_obj_descr *descr)
+int debug_object_activate(void *addr, struct debug_obj_descr *descr)
{
enum debug_obj_state state;
struct debug_bucket *db;
struct debug_obj *obj;
unsigned long flags;
+ int ret;
struct debug_obj o = { .object = addr,
.state = ODEBUG_STATE_NOTAVAILABLE,
.descr = descr };
if (!debug_objects_enabled)
- return;
+ return 0;
db = get_bucket((unsigned long) addr);
@@ -405,23 +407,26 @@
case ODEBUG_STATE_INIT:
case ODEBUG_STATE_INACTIVE:
obj->state = ODEBUG_STATE_ACTIVE;
+ ret = 0;
break;
case ODEBUG_STATE_ACTIVE:
debug_print_object(obj, "activate");
state = obj->state;
raw_spin_unlock_irqrestore(&db->lock, flags);
- debug_object_fixup(descr->fixup_activate, addr, state);
- return;
+ ret = debug_object_fixup(descr->fixup_activate, addr, state);
+ return ret ? -EINVAL : 0;
case ODEBUG_STATE_DESTROYED:
debug_print_object(obj, "activate");
+ ret = -EINVAL;
break;
default:
+ ret = 0;
break;
}
raw_spin_unlock_irqrestore(&db->lock, flags);
- return;
+ return ret;
}
raw_spin_unlock_irqrestore(&db->lock, flags);
@@ -431,8 +436,11 @@
* true or not.
*/
if (debug_object_fixup(descr->fixup_activate, addr,
- ODEBUG_STATE_NOTAVAILABLE))
+ ODEBUG_STATE_NOTAVAILABLE)) {
debug_print_object(&o, "activate");
+ return -EINVAL;
+ }
+ return 0;
}
/**
