Re: [RFC] simple_lmk: Introduce Simple Low Memory Killer for Android

[Oleg Nesterov]

On 05/13, Sultan Alsawaf wrote:
>
> On Fri, May 10, 2019 at 05:10:25PM +0200, Oleg Nesterov wrote:
> > I am starting to think I am ;)
> >
> > If you have task1 != task2 this code
> >
> > 	task_lock(task1);
> > 	task_lock(task2);
> >
> > should trigger print_deadlock_bug(), task1->alloc_lock and task2->alloc_lock are
> > the "same" lock from lockdep pov, held_lock's will have the same hlock_class().
>
> Okay, I've stubbed out debug_locks_off(), and lockdep is now complaining about a
> bunch of false positives so it is _really_ enabled this time.

Could you explain in detail what exactly did you do and what do you see in dmesg?

Just in case, lockdep complains only once, print_circular_bug() does debug_locks_off()
so it it has already reported another false positive __lock_acquire() will simply
return after that.

Oleg.