Date: Tue, 29 Nov 2016 20:52:04 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Petr Mladek <pmladek@suse.com>, Josh Poimboeuf <jpoimboe@redhat.com>,
        Vince Weaver <vincent.weaver@maine.edu>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        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 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.