Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Wed, 31 Aug 2022 14:41:14 +0200
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Daniel Vetter <daniel.vetter@ffwll.ch>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        DRI Development <dri-devel@lists.freedesktop.org>,
        Daniel Vetter <daniel.vetter@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        Ilpo =?utf-8?B?SsOkcnZpbmVu?= <ilpo.jarvinen@linux.intel.com>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        Xuezhi Zhang <zhangxuezhi1@coolpad.com>,
        Yangxi Xiang <xyangxi5@gmail.com>,
        nick black <dankamongmen@gmail.com>,
        Petr Mladek <pmladek@suse.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Luis Chamberlain <mcgrof@kernel.org>,
        "Guilherme G. Piccoli" <gpiccoli@igalia.com>,
        Marco Elver <elver@google.com>,
        John Ogness <john.ogness@linutronix.de>,
        David Gow <davidgow@google.com>,
        tangmeng <tangmeng@uniontech.com>,
        Tiezhu Yang <yangtiezhu@loongson.cn>,
        Chris Wilson <chris@chris-wilson.co.uk>
Subject: Re: [PATCH] kernel/panic: Drop unblank_screen call
Message-ID: <Yw9W6qYo6Acg7rad@linutronix.de>
References: <20220830145004.430545-1-daniel.vetter@ffwll.ch>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <20220830145004.430545-1-daniel.vetter@ffwll.ch>
Precedence: bulk

On 2022-08-30 16:50:04 [+0200], Daniel Vetter wrote:
> Long story short, I have no idea why the direct call to unblank_screen
> survived for so long (the infrastructure to do it properly existed for
> years), nor why it wasn't removed when the console_unblank() call was
> finally added. But it makes a ton more sense to finally do that than
> not - it's just better encapsulation to go through the console
> functions instead of doing a direct call, so let's dare. Plus it
> really does not make much sense to call the only unblank
> implementation there is twice, once without, and once with appropriate
> locking.

Yup, calling it twice is redundant. 
The only difference I see is that the console implementation relies on
CONFIG_VT_CONSOLE while the former relied only on CONFIG_VT. There
should be no console output without CONFIG_VT_CONSOLE so no need to
unblank it.

Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Sebastian