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Date: Wed, 17 Mar 2010 15:21:16 +0800
From: Li Zefan <lizf@cn.fujitsu.com>
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To: Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <peterz@infradead.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>,
       Arnaldo Carvalho de Melo <acme@redhat.com>,
       Paul Mackerras <paulus@samba.org>, LKML <linux-kernel@vger.kernel.org>
Subject: [BUG] perf: hard lockup when using perf-sched
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An idea came to me that running perf-sched with a fork "bomb" might
reveal some bug.

So I wrote a program (attached), and did the following test:

# gcc fork.c
# ./a.out &
# perf sched record

After a few seconds, the machine froze, without printing any message.

I've tried the test both on v2.6.34-rc1 and v2.6.34-rc1-tip+.

I'll send you any other information you need.

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