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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <4BBA3021.9090504@zytor.com>
Date:	Mon, 05 Apr 2010 11:46:57 -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 11:10 AM, Guenter Roeck wrote:
> On Wed, 2010-03-31 at 11:32 -0400, Pekka Enberg wrote:
>> On Wed, Mar 31, 2010 at 4:41 PM, Guenter Roeck
>> <guenter.roeck@...csson.com> wrote:
>>> Current early_printk code writes into VGA memory space even
>>> if CONFIG_VGA_CONSOLE is undefined. This can cause problems
>>> if there is no VGA device in the system, especially if the memory
>>> is used by another device.
>>>
>>> Fix problem by redirecting output to early_serial_console
>>> if CONFIG_VGA_CONSOLE is undefined.
>>>
>>> Signed-off-by: Guenter Roeck <guenter.roeck@...csson.com>
>>
>> Reviewed-by: Pekka Enberg <penberg@...helsinki.fi>
>>
> What will it take to get this patch into the tree ?
> 
> If there are coding style issues or some other unresolved concerns,
> please let me know.
> 

You didn't answer my question (c).

I want to know how you ended up with
boot_params.screen_info.orig_video_isVGA == 1 on a system with no VGA,
which seems like it would have resolved this.

I am *not* inclined to add a compile-time test for what should have been
handed with a runtime test already.

	-hpa

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/