linux-kernel - Re: perf/ftrace lockup on 3.12-rc6 with trigger code

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 24 Oct 2013 14:25:06 -0400 (EDT)
From:	Vince Weaver <vincent.weaver@...ne.edu>
To:	linux-kernel@...r.kernel.org
cc:	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	Arnaldo Carvalho de Melo <acme@...stprotocols.net>,
	Dave Jones <davej@...hat.com>,
	Steven Rostedt <rostedt@...dmis.org>,
	Frederic Weisbecker <fweisbec@...il.com>
Subject: Re: perf/ftrace lockup on 3.12-rc6 with trigger code

On Thu, 24 Oct 2013, Vince Weaver wrote:
> after a month of trying I finally got a small test-case out of my 
> perf_fuzzer suite that triggers a system lockup with just one syscall.
> 
> Attached is the code that triggers it.

And it turns out you can only trigger this specific problem if advanced 
ftrace options are enabled.

CONFIG_KPROBES_ON_FTRACE=y
CONFIG_FUNCTION_TRACER=y
CONFIG_FUNCTION_GRAPH_TRACER=y
CONFIG_STACK_TRACER=y
CONFIG_DYNAMIC_FTRACE=y
CONFIG_DYNAMIC_FTRACE_WITH_REGS=y
CONFIG_FUNCTION_PROFILER=y
CONFIG_FTRACE_MCOUNT_RECORD=y

Urgh, I had turned those on to try to debug something and forgot to 
disable.  I feel like I saw this problem before I had those enabled so I 
guess I have to start from scratch fuzzing to see if I can get a more
generally reproducible trace.

Vince
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/