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From: Markus Wichmann <nullplan@gmx.net>
To: musl@lists.openwall.com
Subject: Re: aio_cancel segmentation fault for in progress write requests
Date: Fri, 7 Dec 2018 21:35:32 +0100	[thread overview]
Message-ID: <20181207203532.GA2554@voyager> (raw)
In-Reply-To: <03a5f237-87cd-5580-4148-a29fa22d3ef0@adelielinux.org>

On Fri, Dec 07, 2018 at 01:13:44PM -0600, A. Wilcox wrote:
> So, my best theory is that running inside a debugger (gdb, valgrind)
> makes it slow enough that it no longer races.

Two ideas to investigate further. 1: Produce a coredump ("ulimit -c
unlimited"). That won't interfere with timing, but I have no clue if
coredumps work with multithreading.

2: Might I suggest installing a SIGSEGV handler? If you have libunwind,
you can create a backtrace from inside the handler. And even if not, you
can at least print the exception PC, which would help a ton already.

Only, don't return from that handler. Either _exit(), or better yet,
restore the default handler, then kill yourself with SIGSEGV.

Ciao,
Markus


  parent reply	other threads:[~2018-12-07 20:35 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-07 12:52 Arkadiusz Sienkiewicz
2018-12-07 15:44 ` Rich Felker
2018-12-07 16:04   ` Arkadiusz Sienkiewicz
2018-12-07 16:52     ` Orivej Desh
2018-12-07 16:52     ` Rich Felker
2018-12-07 17:31       ` A. Wilcox
2018-12-07 18:26         ` Rich Felker
2018-12-07 19:05           ` A. Wilcox
2018-12-07 20:07             ` Rich Felker
2018-12-07 19:13           ` A. Wilcox
2018-12-07 20:21             ` Rich Felker
2018-12-07 20:35             ` Markus Wichmann [this message]
2018-12-07 21:12               ` Rich Felker
2018-12-07 22:51               ` A. Wilcox
2018-12-07 23:50                 ` Rich Felker
2018-12-07 20:06           ` Florian Weimer
2018-12-07 20:14             ` Rich Felker
2018-12-08 16:18               ` Florian Weimer
2018-12-10  9:05                 ` Arkadiusz Sienkiewicz
2018-12-12  0:36                   ` Rich Felker
2018-12-17 14:21                     ` Arkadiusz Sienkiewicz
2018-12-17 17:29                       ` Rich Felker

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