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

[Ingo Molnar]

* Vince Weaver <vincent.weaver@xxxxxxxxx> wrote:

> I don't know if there are any better ways to try to debug things 
> than the printk route.  Though that has its own problems as the 
> printk's themselves start showing up in the ftrace traces.

One additional brute-force method is earlyprintk=...,keep and 
marking the (handful of) earlyprintk functions (and snprintf) 
notrace, plus turning off printk itself completely.

That gives a completely instrumentation-free and locking-free 
console output function of last resort :-/

Thanks,

	Ingo
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