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Subject: Re: tty: deadlock between n_tracerouter_receivebuf and flush_to_ldisc
To: Dmitry Vyukov <dvyukov@google.com>
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From: Peter Hurley <peter@hurleysoftware.com>
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Date: Thu, 4 Feb 2016 10:46:18 -0800
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On 02/04/2016 05:17 AM, Dmitry Vyukov wrote:
> On Thu, Feb 4, 2016 at 1:39 PM, Dmitry Vyukov <dvyukov@google.com> wrote:
>> On Wed, Feb 3, 2016 at 8:09 PM, Peter Hurley <peter@hurleysoftware.com> wrote:

>>> Hopefully, once the problem with the bad stacktraces are fixed, the
>>> actual circular lock dependencies will be clear.

> Found a bug in lockdep. Yes, the first stack is correct, and the saved
> stack is just a random, unrelated stack. Will mail a fix.

Ok, so with the lockdep bug fixed, those reports should now have the
correct stack traces.

I'd appreciate if you could re-generate the original report, so I can examine
if my speculative fix was appropriate.

And then if you would re-generate the more recent report, I'll relook at
that.

Regards,
Peter Hurley