Sebastian Andrzej Siewior 43e01fefac ARM: 8840/1: use a raw_spinlock_t in unwind
[ Upstream commit 74ffe79ae538283bbf7c155e62339f1e5c87b55a ]

Mostly unwind is done with irqs enabled however SLUB may call it with
irqs disabled while creating a new SLUB cache.

I had system freeze while loading a module which called
kmem_cache_create() on init. That means SLUB's __slab_alloc() disabled
interrupts and then

->new_slab_objects()
 ->new_slab()
  ->setup_object()
   ->setup_object_debug()
    ->init_tracking()
     ->set_track()
      ->save_stack_trace()
       ->save_stack_trace_tsk()
        ->walk_stackframe()
         ->unwind_frame()
          ->unwind_find_idx()
           =>spin_lock_irqsave(&unwind_lock);

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:29:08 +02:00
..
2019-02-20 10:18:32 +01:00
2019-03-23 13:19:47 +01:00
2016-10-19 08:39:47 -07:00
2018-11-13 11:16:47 -08:00