linux-kernel - Re: [PATCH 00/17] fbdev: Remove FBINFO_DEFAULT and FBINFO_FLAG

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: <ab92f8d9-36ab-06bc-b85b-d52b7a1bfe9a@suse.de>
Date:   Tue, 11 Jul 2023 08:24:40 +0200
From:   Thomas Zimmermann <tzimmermann@...e.de>
To:     Sam Ravnborg <sam@...nborg.org>
Cc:     deller@....de, javierm@...hat.com, linux-fbdev@...r.kernel.org,
        kvm@...r.kernel.org, linux-hyperv@...r.kernel.org,
        linux-sh@...r.kernel.org, linux-staging@...ts.linux.dev,
        linux-kernel@...r.kernel.org, amd-gfx@...ts.freedesktop.org,
        linux-geode@...ts.infradead.org, dri-devel@...ts.freedesktop.org,
        linux-input@...r.kernel.org, linux-nvidia@...ts.surfsouth.com,
        linux-omap@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
        linux-arm-kernel@...ts.infradead.org, linux-media@...r.kernel.org
Subject: Re: [PATCH 00/17] fbdev: Remove FBINFO_DEFAULT and
 FBINFO_FLAG_DEFAULT flags

Hi Sam

Am 10.07.23 um 19:19 schrieb Sam Ravnborg:
> Hi Thomas,
> 
> On Mon, Jul 10, 2023 at 02:50:04PM +0200, Thomas Zimmermann wrote:
>> Remove the unused flags FBINFO_DEFAULT and FBINFO_FLAG_DEFAULT from
>> fbdev and drivers, as briefly discussed at [1]. Both flags were maybe
>> useful when fbdev had special handling for driver modules. With
>> commit 376b3ff54c9a ("fbdev: Nuke FBINFO_MODULE"), they are both 0
>> and have no further effect.
>>
>> Patches 1 to 7 remove FBINFO_DEFAULT from drivers. Patches 2 to 5
>> split this by the way the fb_info struct is being allocated. All flags
>> are cleared to zero during the allocation.
>>
>> Patches 8 to 16 do the same for FBINFO_FLAG_DEFAULT. Patch 8 fixes
>> an actual bug in how arch/sh uses the tokne for struct fb_videomode,
>> which is unrelated.
>>
>> Patch 17 removes both flag constants from <linux/fb.h>
> 
> We have a few more flags that are unused - should they be nuked too?
> FBINFO_HWACCEL_FILLRECT
> FBINFO_HWACCEL_ROTATE
> FBINFO_HWACCEL_XPAN

It seems those are there for completeness. Nothing sets _ROTATE, the 
others are simply never checked. According to the comments, some are 
required, some are optional. I don't know what that means.

IIRC there were complains about performance when Daniel tried to remove 
fbcon acceleration, so not all _HWACCEL_ flags are unneeded.

Leaving them in for reference/completeness might be an option; or not. I 
have no strong feelings about those flags.

> 
> Unused as in no references from fbdev/core/*
> 
> I would rather see one series nuke all unused FBINFO flags in one go.
> Assuming my quick grep are right and the above can be dropped.

I would not want to extend this series. I'm removing _DEFAULT as it's 
absolutely pointless and confusing.

Best regards
Thomas

> 
> 	Sam

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

Download attachment "OpenPGP_signature" of type "application/pgp-signature" (841 bytes)