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Subject: Re: 2.6.33: ftrace triggers soft lockup
From: Steven Rostedt <rostedt@goodmis.org>
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To: Li Zefan <lizf@cn.fujitsu.com>, Lai Jiangshan <laijs@cn.fujitsu.com>
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       =?ISO-8859-1?Q?Am=E9rico?= Wang <xiyou.wangcong@gmail.com>,
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On Tue, 2010-03-09 at 11:38 +0800, Li Zefan wrote:

> The segfault is from userspace. This is a segfault I just got:
> 
> ftrace_stack_ma[14989]: segfault at fe2e ip 00000000004474c0 sp 00007fffb97e38c0 error 4 in bash[400000+d1000]

Li and Lai,

Thanks a lot for reporting all this, and writing the ftrace_stress_test.
I've fixed all the bugs that it has reported (to my knowledge) and after
a little more testing I will soon be sending a patch series out.

Just wanted to say thanks again, your efforts have helped out
tremendously!

Americo,

I still do not know why the function graph tracer is making your system
unusable. I'll look more into that when I get a chance. So far, I have
not had any issues on any of my boxes.

-- Steve