linux-kernel - Re: [PATCH] arm64: kernel: need extern variable 'screen

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: <519B278B.6030708@asianux.com>
Date:	Tue, 21 May 2013 15:51:39 +0800
From:	Chen Gang <gang.chen@...anux.com>
To:	Geert Uytterhoeven <geert@...ux-m68k.org>
CC:	Will Deacon <will.deacon@....com>,
	Catalin Marinas <Catalin.Marinas@....com>,
	Arnd Bergmann <arnd@...db.de>,
	Tony Lindgren <tony@...mide.com>,
	Santosh Shilimkar <santosh.shilimkar@...com>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] arm64: kernel: need extern variable 'screen_info' for
 related driver using.

On 05/21/2013 02:57 PM, Geert Uytterhoeven wrote:
> On Tue, May 21, 2013 at 5:15 AM, Chen Gang <gang.chen@...anux.com> wrote:
>>> >> I think it would be better if we added a something like
>>> >> CONFIG_HAVE_VGA_CONSOLE, which VGA_CONSOLE can then depend on. Architectures
>>> >> like x86 can then select the former, and we can remove the long list of
>>> >> architectures from the current option.
>> >
>> > I guess your meaning is:
>> >
>> >   under arm64, actually, need not support 'VGA_CONSOLE', and 'screen_info' is useless.
>> >   So better to define 'CONFIG_HAVE_VGA_CONSOLE' which 'VGA_CONSOLE' can depend on it, and in arm64, we do not define CONFIG_HAVE_VGA_CONSOLE.
>> >
>> > Is it correct ?
> No, you missed "and we can remove the long list of architectures from the
> current option".
> 

OK, thanks.

Is it correct: "it is unnecessary to add 'screen_info' to the code, for
arm64 will never support 'VGA_CONSOLE'" ?

>> > If so, I recommend to add depend item for VGA_CONSOLE directly:
> I strongly support CONFIG_HAVE_VGA_CONSOLE.

For me, I still recommend add 'ARM64' in the long list of architectures
for 'VGA_CONSOLE', I have 3 reasons, please check:

a. current implementation only changes one area which only related with
arm64 and 'VGA_CONSOLE', but if use 'CONFIG_HAVE_VGA_CONSOLE', that will
touch many multiple platforms dependency, at least we need discuss about
it with multiple platforms guys for it, firstly.

b. We can find some cases to use CONFIG_HAVE_* as dpend on, but I can
not find any cases which let CONFIG_'samename' depend on
CONFIG_HAVE_'samename'.

c. The original way still has effect, although it seems not quit
beautiful, but it is correct and still clear for readers, it is still
sustainable.

Thanks.
-- 
Chen Gang

Asianux Corporation
--
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/