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Date:   Thu, 18 Apr 2019 17:24:43 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Josh Poimboeuf <jpoimboe@redhat.com>,
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Subject: Re: [patch V2 01/29] tracing: Cleanup stack trace code
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On Thu, 18 Apr 2019 23:14:45 +0200 (CEST)
Thomas Gleixner <tglx@linutronix.de> wrote:

> On Thu, 18 Apr 2019, Josh Poimboeuf wrote:
> 
> > On Thu, Apr 18, 2019 at 10:41:20AM +0200, Thomas Gleixner wrote:  
> > > - Remove the extra array member of stack_dump_trace[]. It's not required as
> > >   the stack tracer stores at max array size - 1 entries so there is still
> > >   an empty slot.  
> > 
> > What is the empty slot used for?  
> 
> I was trying to find an answer but failed. Maybe it's just historical
> leftovers or Steven knows where the magic is in this maze.
>

I believe it was for historical leftovers (there was a time it was
required), and left there for "paranoid" sake. But let me apply the
patch and see if it is really needed.

-- Steve