From: Markus Elfring <Markus.Elfring@web.de>
To: Dan Carpenter <dan.carpenter@linaro.org>,
Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
freedreno@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
linux-arm-msm@vger.kernel.org
Cc: kernel-janitors@vger.kernel.org,
Abhinav Kumar <quic_abhinavk@quicinc.com>,
Archit Taneja <architt@codeaurora.org>,
Daniel Vetter <daniel@ffwll.ch>, David Airlie <airlied@gmail.com>,
Jeykumar Sankaran <jsanka@codeaurora.org>,
Jordan Crouse <jordan@cosmicpenguin.net>,
Marijn Suijten <marijn.suijten@somainline.org>,
Rob Clark <robdclark@gmail.com>, Sean Paul <sean@poorly.run>,
Simona Vetter <simona@ffwll.ch>, Vinod Koul <vkoul@kernel.org>,
cocci@inria.fr, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [RESEND] drm/msm/dpu: Delete a variable initialisation before a null pointer check in two functions
Date: Mon, 3 Mar 2025 09:15:14 +0100 [thread overview]
Message-ID: <12050afd-ab60-4bac-bd25-0c3cc925b38b@web.de> (raw)
In-Reply-To: <29b32b0d-312d-4848-9e26-9e5e76e527a7@stanley.mountain>
>>> The address of a data structure member was determined before
>>> a corresponding null pointer check in the implementation of
>>> the functions “dpu_hw_pp_enable_te” and “dpu_hw_pp_get_vsync_info”.
>>>
>>> Thus avoid the risk for undefined behaviour by removing extra
>>> initialisations for the variable “c” (also because it was already
>>> reassigned with the same value behind this pointer check).
>
> There is no undefined behavior here.
Will any software development concerns evolve further also according to
undesirable null pointer dereferences?
https://wiki.sei.cmu.edu/confluence/display/c/EXP34-C.+Do+not+dereference+null+pointers
Regards,
Markus
next prev parent reply other threads:[~2025-03-03 8:15 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <40c60719-4bfe-b1a4-ead7-724b84637f55@web.de>
[not found] ` <1a11455f-ab57-dce0-1677-6beb8492a257@web.de>
[not found] ` <13566308-9a80-e4aa-f64e-978c02b1406d@web.de>
2023-04-11 16:43 ` [PATCH] drm/msm/dpu: Delete a variable initialisation before a null pointer check in two functions Dmitry Baryshkov
2023-04-11 16:44 ` Abhinav Kumar
2025-03-02 20:56 ` [PATCH RESEND] " Markus Elfring
2025-03-02 23:01 ` Dmitry Baryshkov
2025-03-03 7:14 ` Dan Carpenter
2025-03-03 8:15 ` Markus Elfring [this message]
2025-03-03 8:24 ` [RESEND] " Dan Carpenter
2025-03-05 8:40 ` [RFC] Clarification for “undefined behaviour”? Markus Elfring
2025-03-05 8:51 ` Dan Carpenter
2025-03-05 9:20 ` Markus Elfring
2025-03-05 14:17 ` David Laight
2025-03-05 14:30 ` Dan Carpenter
2025-03-05 21:35 ` David Laight
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