Date: Fri, 25 Mar 2011 14:41:58 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Ming Lei <tom.leiming@gmail.com>, torvalds@osdl.org,
        Ingo Molnar <mingo@elte.hu>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: deadlock caused by printk
Message-ID: <20110325184158.GE9313@home.goodmis.org>
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On Fri, Mar 25, 2011 at 03:50:27PM +0100, Peter Zijlstra wrote:
> On Fri, 2011-03-25 at 22:30 +0800, Ming Lei wrote:
> > 
> > But seems ftrace can't dump out the messages if system hangs,
> 
> True.

Well, matters how the system hangs. Add in a nmi watchdog or other
watchdogs which can also trigger the ftrace_dump_on_oops.

> 
> >  so could
> > we introduce a smart and simple "printk" which can be used in any
> > contexts? 
> 
> I think you could use early_printk() for that, it doesn't bother with
> all the syslog muck.
>

Heh, I should have read the thread before replying to the first post ;)

-- Steve

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