From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f54.google.com (mail-ot1-f54.google.com [209.85.210.54]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3679927707 for ; Tue, 14 Jul 2026 15:46:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.54 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784043976; cv=none; b=s0yVlXRttCgKPE1rngY0vTDQjfviMAcxtLs3hTETWyZu2yces7eN8JrPbiThv7vUHizpGR/4tj2ZtTSFL4rFE0th6J+v1ZchtmYzjdeJUuEmTyKEoCmKvwtzJ0QSORpWpsyWvkmPFIWKndxUD2JkkQAKRNlbLLgki5xNUj1UKlE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784043976; c=relaxed/simple; bh=Fp3HYrbb7PdOhzMKQ5EfcrzRnU05kLPwbocKk8hhCgg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QtxV4J8hZLoY5WHpdRoqgANoNSryo5Yf4eL5gEq3KsGddpItBCQgohka4JUyvo/PCHYri9GUj9AZ1WoTXSkHjB9nllorhAb7VUJ/86PAPgkUdzGwM6HG9+vgxy+IHXcinFaT9WlbdUO2AB1nFeahnNLmCTIBrCVIvlu0NVwQRHw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=ntUfFjiW; arc=none smtp.client-ip=209.85.210.54 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ntUfFjiW" Received: by mail-ot1-f54.google.com with SMTP id 46e09a7af769-7e9f829d75aso731840a34.0 for ; Tue, 14 Jul 2026 08:46:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1784043974; x=1784648774; darn=vger.kernel.org; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to:content-type; bh=nNt4aFBQBTeC6gh7XjshPB2bRqBQHmW7ChcRLsTBtjU=; b=ntUfFjiWVhAYvidHnS8lcRjsP87CDHFdpdKF950ToE8Y1ymr5Qq8zt3af/1UHkPC+3 vSVViRBmo5/ehzwRE+P5NiDqY9Wk7ZoeFGyucOj5o4fefCw7LDh3uvtXSWxy5eYyJ14L FZKX4I5WGQfEFeIOX7Ggtw4xIHZX09BsWoae+hecQbczKTzaY3QMU5BMpTwzyP4pYYxL 2CQFkPdsqNMOFRqJeQr4Ay2NqVfPmvylj+MQFQXjTgyCl6+0qdd7nAl4T9ENMABaNXga JPBF00Se1bY0bBf+jqpk9A/ZluX0JDtJCcmmj1v0ScyCXXdnTVE0QPc484mn19yuNnCs 8WoQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784043974; x=1784648774; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:from :date:x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=nNt4aFBQBTeC6gh7XjshPB2bRqBQHmW7ChcRLsTBtjU=; b=FCQm1E4uLfF31elSdePmAI5epNGOXHiknSEa2crs9AzzThOFcQP3B+Xuz9RVVSRbwq wNRjfIE48Lcjo1xRbooBWO5m5Yzjfzcw7DqD+PsrAiXqX0ayg3SDgqe9IIb/jMWndUlZ GMb/4XVbTXJkez1WyiFxazkagFNooUcRn+l2O1dNJoRmywyGOn/MxmxKNvd6Qr2nVBmS ltqlCf3IGuZYxkbf97C0DXRX7YbPc8YR96QI2A/i7N1N74ERmOgpI3zQ79cfQE8aGm8t LPHOg1RXh02paV0HxXKHXPH+mH7Ifxo81KCqeGPrZNZFcse3qtMSRQAa8WMM3+hejm8W DK6A== X-Forwarded-Encrypted: i=1; AFNElJ/r2AZRBM3QFCP7N2hUfM9NIBdZcTgb3HMbNnbb7oP99XIYL+ifwhFtw2yn1puXrU1v8uuxSKz8uXf5iIs=@vger.kernel.org X-Gm-Message-State: AOJu0Yw8SRYy9uMpOUqSM0HMVaIqO+O2oQTCEBpY+7OyoNLCkwIl/EfT uD7zf9/kazIOzUeYZ808EHLO61lc7ym1X+qc9h9ZqwG64U6beJvkMhca X-Gm-Gg: AfdE7cn4DWYVImb93wZFMcBtcrRgxKJfS5kDvbSC0BAbrMompdNitsUO2NJHaaE62ze uJ5nOPeAmpO2Kqv1jn02mDtvtFGSiZiqW/YPFiuHsu+vZmNy4KeR/45QS01SAIcCYcV+R/len5X WLx2kwssiHJG8qXywstxoj15NqdWJNkWVNsb5bvdTYo+ju5kWqaQX1lbHckCenNDpvpbwcli7tk mVr97/T3rfmSaReYPi3AAzmKAhlxekN0nkZq3NRwanXdUNpe4iS2jaJ7W/Bn95qFdwPccWilFbq lqjdGR2LaY6LIpXirA88HxFsOhEcIa5hiS1xnHoJwgphERnal7byLxW8H6mDJJvRZMIRXGmt7SL W9Qgye0WyJWSZOhDBinj0K9AxPMoBjDJYfez8bXE9P54cYdI+0TKJK7OiEltQClYqEQqQA6+KMJ f5wGhToap3VKAQta4= X-Received: by 2002:a05:6830:3108:b0:7e9:c76c:abe3 with SMTP id 46e09a7af769-7ec096027a7mr9375213a34.6.1784043974139; Tue, 14 Jul 2026 08:46:14 -0700 (PDT) Received: from localhost ([74.80.182.78]) by smtp.gmail.com with ESMTPSA id 46e09a7af769-7ebcb2bc241sm15641928a34.20.2026.07.14.08.46.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Jul 2026 08:46:12 -0700 (PDT) Date: Tue, 14 Jul 2026 18:46:06 +0300 From: Dan Carpenter To: Rodrigo Vivi Cc: Markus Elfring , intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org, David Airlie , Jani Nikula , Joonas Lahtinen , Simona Vetter , Tvrtko Ursulin , Ville =?iso-8859-1?Q?Syrj=E4l=E4?= , LKML , kernel-janitors@vger.kernel.org Subject: Re: [PATCH] drm/i915/bios: Move a variable assignment behind a null pointer check in intel_bios_encoder_supports_dp_dual_mode() Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Tue, Jul 14, 2026 at 11:28:23AM -0400, Rodrigo Vivi wrote: > On Mon, Jul 13, 2026 at 04:05:53PM +0200, Markus Elfring wrote: > > From: Markus Elfring > > Date: Mon, 13 Jul 2026 15:56:46 +0200 > > > > The address of a data structure member was determined before > > a corresponding null pointer check in the implementation of > > the function “intel_bios_encoder_supports_dp_dual_mode”. > > > > Thus avoid the risk for undefined behaviour by reducing the scope for > > the variable “child” behind condition checks. > > > > This issue was detected by using the Coccinelle software. > > > > Fixes: 044cbc7a74c136f12a80c855cadd1b085084aef1 ("drm/i915/bios: Nuke DEVICE_TYPE_DP_DUAL_MODE_BITS") > > Cc: stable@vger.kernel.org Please stop adding Fixes tags to these and talking about "undefined behavior" in the commit message. Pointer math is defined... It's just a style preference on your part. regards, dan carpenter