On Wed, 4 May 2016, Petr Mladek wrote:

quoted

+
+		if (unlikely(klp_patch_pending(current)))
+			klp_patch_task(current);
 	}

Some more ideas from the world of crazy races. I was shaking my head
if this was safe or not.

The problem might be if the task get rescheduled between the check
for the pending stuff 

The code in question is running with preemption disabled.

or inside the klp_patch_task() function. 

We must make sure that this function doesn't go to sleep. It's only used 
to clear the task_struct flag anyway.

-- 
Jiri Kosina
SUSE Labs