linux-kernel - Re: [PATCH v2 9/9] drm/panel: truly-nt35597: Don't log an error when DSI host can't be found

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: <ceee318c-1d57-4b3d-9754-1a9ee53fc4e2@collabora.com>
Date: Fri, 1 Mar 2024 10:37:34 +0100
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>
To: Laurent Pinchart <laurent.pinchart@...asonboard.com>
Cc: Nícolas F. R. A. Prado <nfraprado@...labora.com>,
 Andrzej Hajda <andrzej.hajda@...el.com>,
 Neil Armstrong <neil.armstrong@...aro.org>, Robert Foss <rfoss@...nel.org>,
 Jonas Karlman <jonas@...boo.se>, Jernej Skrabec <jernej.skrabec@...il.com>,
 Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
 Maxime Ripard <mripard@...nel.org>, Thomas Zimmermann <tzimmermann@...e.de>,
 David Airlie <airlied@...il.com>, Daniel Vetter <daniel@...ll.ch>,
 owen <qwt9588@...il.com>, Jagan Teki <jagan@...rulasolutions.com>,
 Marek Vasut <marex@...x.de>, Adrien Grassein <adrien.grassein@...il.com>,
 Srinivas Kandagatla <srinivas.kandagatla@...aro.org>,
 Sam Ravnborg <sam@...nborg.org>, Bjorn Andersson <andersson@...nel.org>,
 Vinod Koul <vkoul@...nel.org>, Dmitry Baryshkov
 <dmitry.baryshkov@...aro.org>, Vinay Simha BN <simhavcs@...il.com>,
 Christopher Vollo <chris@...ewoutreach.org>,
 Jessica Zhang <quic_jesszhan@...cinc.com>,
 Marijn Suijten <marijn.suijten@...ainline.org>,
 AngeloGioacchino Del Regno <angelogioacchino.delregno@...ainline.org>,
 kernel@...labora.com, dri-devel@...ts.freedesktop.org,
 linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 9/9] drm/panel: truly-nt35597: Don't log an error when
 DSI host can't be found

Il 01/03/24 09:56, Laurent Pinchart ha scritto:
> On Fri, Mar 01, 2024 at 09:44:36AM +0100, AngeloGioacchino Del Regno wrote:
>> Il 01/03/24 07:30, Laurent Pinchart ha scritto:
>>> On Thu, Feb 29, 2024 at 07:12:15PM -0500, Nícolas F. R. A. Prado wrote:
>>>> Given that failing to find a DSI host causes the driver to defer probe,
>>>> make use of dev_err_probe() to log the reason. This makes the defer
>>>> probe reason available and avoids alerting userspace about something
>>>> that is not necessarily an error.
>>>>
>>>> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>
>>>> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@...labora.com>
>>>> ---
>>>>    drivers/gpu/drm/panel/panel-truly-nt35597.c | 6 ++----
>>>>    1 file changed, 2 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/panel/panel-truly-nt35597.c b/drivers/gpu/drm/panel/panel-truly-nt35597.c
>>>> index b73448cf349d..d447db912a61 100644
>>>> --- a/drivers/gpu/drm/panel/panel-truly-nt35597.c
>>>> +++ b/drivers/gpu/drm/panel/panel-truly-nt35597.c
>>>> @@ -550,10 +550,8 @@ static int truly_nt35597_probe(struct mipi_dsi_device *dsi)
>>>>    
>>>>    	dsi1_host = of_find_mipi_dsi_host_by_node(dsi1);
>>>>    	of_node_put(dsi1);
>>>> -	if (!dsi1_host) {
>>>> -		dev_err(dev, "failed to find dsi host\n");
>>>> -		return -EPROBE_DEFER;
>>>> -	}
>>>> +	if (!dsi1_host)
>>>> +		return dev_err_probe(dev, -EPROBE_DEFER, "failed to find dsi host\n");
>>>
>>> 		return dev_err_probe(dev, -EPROBE_DEFER,
>>> 				     "failed to find dsi host\n");
>>>
>>> With this addressed,
>>
>> I disagree. That's 87 columns, and the 80-col rule is long gone.
> 
> It's still a maintainer's preference. I soft-enforce it in drivers I
> maintain. In this case I'll let Neil decide, as he's listed as the
> maintainer for drivers/gpu/drm/panel/.
> 

Yes, that's right. Comes down to personal opinion.

Cheers

>> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>
>>
>>> Reviewed-by: Laurent Pinchart <laurent.pinchart@...asonboard.com>
>>>
>>>>    
>>>>    	/* register the second DSI device */
>>>>    	dsi1_device = mipi_dsi_device_register_full(dsi1_host, &info);
>