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Date:   Thu, 3 Feb 2022 22:27:31 +0100
From:   Sam Ravnborg <sam@ravnborg.org>
To:     Daniel Vetter <daniel.vetter@ffwll.ch>
Cc:     DRI Development <dri-devel@lists.freedesktop.org>,
        linux-fbdev@vger.kernel.org,
        Intel Graphics Development <intel-gfx@lists.freedesktop.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Qing Wang <wangqing@vivo.com>,
        Daniel Vetter <daniel.vetter@intel.com>,
        Helge Deller <deller@gmx.de>
Subject: Re: [PATCH 07/21] fbdev/sysfs: Fix locking
Message-ID: <YfxIw83tbU4lrpKj@ravnborg.org>
References: <20220131210552.482606-1-daniel.vetter@ffwll.ch>
 <20220131210552.482606-8-daniel.vetter@ffwll.ch>
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On Mon, Jan 31, 2022 at 10:05:38PM +0100, Daniel Vetter wrote:
> fb_set_var requires we hold the fb_info lock. Or at least this now
> matches what the ioctl does ...
> 
> Note that ps3fb and sh_mobile_lcdcfb are busted in different ways here,
> but I will not fix them up.
> 
> Also in practice this isn't a big deal, because really variable fbdev
> state is actually protected by console_lock (because fbcon just
> doesn't bother with lock_fb_info() at all), and lock_fb_info
> protecting anything is really just a neat lie. But that's a much
> bigger fish to fry.
> 
> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> Cc: Helge Deller <deller@gmx.de>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Qing Wang <wangqing@vivo.com>
> Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>