Re: [BUG 3.12.rc4] Oops: unable to handle kernel paging request during shutdown

[Ingo Molnar <mingo@kernel.org>]

* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Fri, Oct 25, 2013 at 11:23 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
> >
> > Enable DEBUG_OBJECTS, DEBUG_OBJECTS_FREE, DEBUG_OBJECTS_TIMERS
> 
> Yes, but nobody has actually been able to trigger it with those. 
> It's pretty rare, and the debug options are so expensive that they 
> aren't reasonable to enable generally...
> 
> So we need to try to figure out how to trigger it, or narrow 
> things down some way..

If it's timing then maybe the 1 seconds delay isn't enough 
(especially if it's boot related, where we have a couple of delays 
already) - the patch below triples it.

(If the bug goes away due to some other side effect then this patch 
won't make a difference to reproducability.)

Thanks,

	Ingo

diff --git a/lib/kobject.c b/lib/kobject.c
index 084f7b1..124188f 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -595,7 +595,7 @@ static void kobject_release(struct kref *kref)
 	pr_info("kobject: '%s' (%p): %s, parent %p (delayed)\n",
 		 kobject_name(kobj), kobj, __func__, kobj->parent);
 	INIT_DELAYED_WORK(&kobj->release, kobject_delayed_cleanup);
-	schedule_delayed_work(&kobj->release, HZ);
+	schedule_delayed_work(&kobj->release, 3*HZ);
 #else
 	kobject_cleanup(kobj);
 #endif