linux-kernel - Re: [PATCH v3 4/4] fbdev: sh_mobile_lcdc: Make FB

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] [day] [month] [year] [list]

Message-ID: <af800a37-150b-4b7f-ad83-4db6e7e72df9@gmail.com>
Date: Mon, 5 Jan 2026 21:07:52 -0800
From: Chintan Patel <chintanlike@...il.com>
To: Andy Shevchenko <andriy.shevchenko@...el.com>,
 Helge Deller <deller@....de>
Cc: Helge Deller <deller@...nel.org>, andy <andy@...nel.org>,
 linux-fbdev@...r.kernel.org, linux-omap@...r.kernel.org,
 linux-kernel@...r.kernel.org, dri-devel@...ts.freedesktop.org
Subject: Re: [PATCH v3 4/4] fbdev: sh_mobile_lcdc: Make FB_DEVICE dependency
 optional



On 1/3/26 05:15, Andy Shevchenko wrote:
> On Sat, Jan 03, 2026 at 10:59:44AM +0100, Helge Deller wrote:
>> On 12/30/25 19:25, Chintan Patel wrote:
>>> On 12/30/25 00:13, Helge Deller wrote:
> 
> ...
> 
>>>>> -ATTRIBUTE_GROUPS(overlay_sysfs);
>>>>
>>>> Instead of replacing the ^ ATTRIBUTE_GROUPS() by the code below,
>>>> isn't it possible to just mark the overlay_sysfs_attrs[] array
>>>> _maybe_unused, and just do:
>>>> + #ifdef CONFIG_FB_DEVICE
>>>> + ATTRIBUTE_GROUPS(overlay_sysfs);
>>>> + #endif
>>>>
>>>> ?
>>>
>>> Yes, the __maybe_unused + #ifdef ATTRIBUTE_GROUPS() approach would work.
>>>
>>> I went with the PTR_IF(IS_ENABLED()) pattern because Andy suggested
>>> using PTR_IF() to conditionally include overlay_sysfs_group in
>>> overlay_sysfs_groups, and to keep .dev_groups always populated while
>>> letting the device core skip NULL groups. This avoids conditional
>>> wiring via #ifdef and keeps the code type-checked without
>>> CONFIG_FB_DEVICE.
>>> If you still prefer the simpler #ifdef ATTRIBUTE_GROUPS() approach
>>> for this driver, I can switch to that, but I wanted to follow Andy’s
>>> guidance here.
>>
>> I assume Andy will agree to my suggested approach, as it's cleaner
>> and avoids code bloat/duplication. Maybe you send out a v4 with my
>> suggested approach, then it's easier to judge... ?
> 
> I'm also fine with original code. But a suggested approach would work as well
> (at least like it sounds from the above description). Ideally would be nice to
> get rid of ifdeffery completely (that's why we have PTR_IF() for), although
> it might be not so readable. TL;DR: the most readable solution is the winner.
> 
Thank you both! I will send v4 with Helge's suggestion and take it from 
there.