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Date:   Thu, 27 May 2021 08:22:24 +0200
Message-ID: <s5hmtsg8zmn.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Dmitry Osipenko <digetx@gmail.com>
Cc:     Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
Subject: Re: [PATCH] Input: elants_i2c - Fix NULL dereference at probing
In-Reply-To: <b7fc167b-23c6-fd64-cfbf-dd16a90fbf63@gmail.com>
References: <20210526194301.28780-1-tiwai@suse.de>
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        <b7fc167b-23c6-fd64-cfbf-dd16a90fbf63@gmail.com>
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On Wed, 26 May 2021 22:44:59 +0200,
Dmitry Osipenko wrote:
> 
> Hello all,
> 
> 26.05.2021 23:19, Dmitry Torokhov пишет:
> > Hi Takashi,
> > 
> > On Wed, May 26, 2021 at 09:43:01PM +0200, Takashi Iwai wrote:
> >> The recent change in elants_i2c driver to support more chips
> >> introduced a regression leading to Oops at probing.  The driver reads
> >> id->driver_data, but the id may be NULL depending on the device type
> >> the driver gets bound.
> >>
> >> Add a NULL check and falls back to the default EKTH3500.
> > 
> > Thank you for the patch. I think my preference would be to switch to
> > device_get_match_data() and annotate the rest of the match tables with
> > proper controller types.
> 
> Doesn't a NULL mean that elants_i2c_id[] table fails to match the ACPI
> device name? What is the name then?

I don't own the device, so we need to ask on (open)SUSE Bugzilla.

> This could be two patches:
>   1 - trivial fix that can be backported easily
>   2 - switch to device_get_match_data()

I guess 2 is easy enough to backport to 5.12.x.  Let's see.


thanks,

Takashi