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Date: Tue, 29 Nov 2016 12:07:11 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>, Josh Poimboeuf <jpoimboe@redhat.com>,
        Vince Weaver <vincent.weaver@maine.edu>,
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        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        "dvyukov@google.com" <dvyukov@google.com>
Subject: Re: perf: fuzzer BUG: KASAN: stack-out-of-bounds in __unwind_start
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On Tue, Nov 29, 2016 at 08:52:04PM +0100, Peter Zijlstra wrote:
> On Tue, Nov 29, 2016 at 11:39:35AM -0800, Paul E. McKenney wrote:
> > On Tue, Nov 29, 2016 at 06:10:38PM +0100, Peter Zijlstra wrote:
> 
> > > It mostly works, most of the time, and that seems to be what Linus
> > > wants, since its really the best we can have given the constraints. But
> > > for debugging, when you have a UART, it totally blows.
> > 
> > UART???  They still make those things???  ;-)
> 
> Yes, most computer like devices actually have them, trouble is, most
> consumer devices don't have the pins exposed. Luckily most server class
> hardware still does.
> 
> And they're absolutely _awesome_ for debugging; getting data out is a
> matter of trivial MMIO poll loops. Rock solid stuff.

They very clearly need to bring the baud rate into the current millenium,
many tens of Mbaud at the -very- least.

							Thanx, Paul