linux-kernel - Re: [PATCH][RESEND] x86: Do not write to VGA memory space if CONFIG_VGA

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Date:	Mon, 05 Apr 2010 14:11:15 -0700
From:	"H. Peter Anvin" <hpa@...or.com>
To:	guenter.roeck@...csson.com
CC:	linux-kernel@...r.kernel.org, penberg@...helsinki.fi,
	mingo@...hat.com, x86@...nel.org
Subject: Re: [PATCH][RESEND] x86: Do not write to VGA memory space if CONFIG_VGA_CONSOLE
 is undefined

On 04/05/2010 02:04 PM, Guenter Roeck wrote:
> 
> Would you accept a minimized patch like this ?
> 
>  /* Direct interface for emergencies */
> +#ifdef CONFIG_VGA_CONSOLE
>  static struct console *early_console = &early_vga_console;
> +#else
> +static struct console *early_console = &early_serial_console;
> +#endif
>  static int __initdata early_console_initialized;
> 
> This would prevent the problem while minimizing changes, and at the same
> time permit early messages to be written to the serial console.
> 

I'm unhappy about it, because *those early messages shouldn't exist in
the first place*.  It seems to be an indication that we're invoking
setup_early_printk() too late.  The whole playing around with max_xpos
and max_ypos instead of using boot_params.screen_info directly is
particularly bleacherous.

I would at least like to see if the improper invocation of
early_printk() can be avoided.

	-hpa
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