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Date:	Fri, 21 Jul 2006 06:05:13 -0700
From:	Andrew Morton <akpm@osdl.org>
To:	Rodolfo Giometti <giometti@linux.it>
Cc:	linux-kernel@vger.kernel.org, linux-mips@linux-mips.org
Subject: Re: [PATCH] no console disabling during suspend stage
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On Wed, 19 Jul 2006 11:16:00 +0200
Rodolfo Giometti <giometti@linux.it> wrote:

> here a little patch to avoid disabling console during suspend stage
> while we are debugging kernel.
> 
> ...
>
> --- kernel/power/main.c	2006-07-19 10:54:11.000000000 +0200
> +++ kernel/power/main.c.new	2006-07-18 19:38:41.000000000 +0200
> @@ -86,7 +86,9 @@
>  			goto Thaw;
>  	}
>  
> +#ifndef CONFIG_DEBUG_KERNEL
>  	suspend_console();
> +#endif

CONFIG_DEBUG_KERNEL is not really the appropriate thing to use here - it's
more a user-interface/Kconfig level thing.

Can you please describe the problems which suspend_console() are causing?

Some runtime knob might be more appropriate.  Perhaps /sys/power/debug?

If the suspend_console() call is to be disabled then you'll want to disable
the matching resume_console() call too.

printk.c needs sem2mutex conversion.

The console_suspended/secondary_console_sem handling is racy.  Bad Linus. 
But as we're running on a single CPU and all other tasks are frozen it
doesn't matter.