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From: Rusty Russell <rusty@rustcorp.com.au>
To: Oleg Nesterov <oleg@redhat.com>, Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [may-be-patch?] introduce MODULE_USE_UNEXPORTED()
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Date: Thu, 21 Jul 2011 17:29:25 +0930
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On Tue, 19 Jul 2011 20:45:36 +0200, Oleg Nesterov <oleg@redhat.com> wrote:
> Hi.
> 
> >From time to time I need to write a module for debugging purposes,
> and it is a bit annoying I can't simply use, say, put_task_struct().
> 
> Can't we do something like the simple patch below? Of course, it
> is very unsafe to use kallsyms_lookup_name() by many reasons. But
> it looks handy for the testing/debugging.
> 
> Yes, I am not saying this feature is terribly useful, so I agree
> in advance with the "go away, we don't need this hack" nack.
> 
> Still, what do you think?
> 
> Oleg.

I hate it, but I've wanted it too...

Can we bury it under a CONFIG_DEBUG_KERNEL option?  I don't want
distributions turning this on.  And add a GPL license check.

Alternative is to have a "void *khacker_lookup_sym(const char *)" which
does this at runtime, but that's less convenient to use than this.

Thanks,
Rusty.