From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.13]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7F58835CB87; Tue, 13 Jan 2026 19:25:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768332325; cv=none; b=i5v+a7yIauge0MXzmQ3AryI3QcCiEw/q3sGE9s5yyhCoPkDXre2HqZpfTlW0wvMZMo7If8tF/jv0ZRsOkTctJuSEqd62R9PzcpIQxItfAFcndUraliknFuw4Udq+N49Qbj7ldHg6OZwGx9mtpAioMdIT71SbNutaPn9kZzkhM0Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768332325; c=relaxed/simple; bh=yCZgrq2gYyA9zE0wb2KLgXsq/Rqlgw0FrOGx53fXziE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=smPjW+xzjn/wAAZSRGJr3TD179jJMgKouENzfDPFvQeS1HS9zrL3c9IEvp5/ZhIODfeRBQqKa4VGVXog9OR0MSlkIVldA3DyevokEwhaReup2mRSUrhGa9TcxNvtABpxgnBW/ZqJTUGsiLgueT1A+YE2FyuPwtktfCpML2s4QUI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=H9dsLTTL; arc=none smtp.client-ip=198.175.65.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="H9dsLTTL" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1768332323; x=1799868323; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=yCZgrq2gYyA9zE0wb2KLgXsq/Rqlgw0FrOGx53fXziE=; b=H9dsLTTLnj5Z7WAEJe2J6h5UBPtMh3scpZQ8Yc+lWPF7WYK28RcpTWCG spnpP5WpL+O+kjKY7Z6VU7PNGpkwPtEGGBIBQ/ALL33OyyHGcH9PMDIeg zHzva0ioW9YKM8pc8imgS0Cc6X1JZLpAifQDrFP61k6EEDL0K1+ViZH8s VpR8qzhie3wgXR3T2S2wOyCarGF6JGNYYy6Ux4EBtxMSV3fcbKKcnCKr6 FfSkCAvlE5ZhBshEG1V8f8nhnGk2wGeuuwK0Ngm4LYOU6ZL4vE7vebE8B KvyJrr5WK2J3BmwY3hxZWgWbvt5MsA1RoPuPu29m3VMNjEO63h2yRfJ4n w==; X-CSE-ConnectionGUID: mTchf4MSRvWVziljjX9nPA== X-CSE-MsgGUID: KYsj07I5R+O5aMzzScX4eA== X-IronPort-AV: E=McAfee;i="6800,10657,11670"; a="80736989" X-IronPort-AV: E=Sophos;i="6.21,222,1763452800"; d="scan'208";a="80736989" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by orvoesa105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jan 2026 11:25:23 -0800 X-CSE-ConnectionGUID: FVxHAmWTQN+R9F0Owfg4aw== X-CSE-MsgGUID: vWjhIWe8SMGKp9mUgCbK4g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,222,1763452800"; d="scan'208";a="209516040" Received: from klitkey1-mobl1.ger.corp.intel.com (HELO kekkonen.fi.intel.com) ([10.245.244.58]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jan 2026 11:25:21 -0800 Received: from kekkonen.localdomain (localhost [IPv6:::1]) by kekkonen.fi.intel.com (Postfix) with SMTP id BE5C6121DBB; Tue, 13 Jan 2026 21:25:18 +0200 (EET) Date: Tue, 13 Jan 2026 21:25:18 +0200 Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo From: Sakari Ailus To: Jacopo Mondi Cc: "jempty.liang" , Laurent Pinchart , dan.scally@ideasonboard.com, mchehab@kernel.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] media: mali-c55: Fix NULL dev stream alert for tpg sub-device Message-ID: References: <20260113075722.143238-1-imntjempty@163.com> 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=us-ascii Content-Disposition: inline In-Reply-To: Hi Jacopo, On Tue, Jan 13, 2026 at 01:43:12PM +0100, Jacopo Mondi wrote: > Hi Sakari > > On Tue, Jan 13, 2026 at 12:40:25PM +0200, Sakari Ailus wrote: > > Hi Jacopo, > > > > On Tue, Jan 13, 2026 at 09:55:10AM +0100, Jacopo Mondi wrote: > > > I wonder if v4l2_device_register_subdev() shouldn't WARN or if return > > > an error if sd->dev is not initialized. Laurent, Sakari: opinions ? > > > > I might even return an error but I wonder what would break. Perhaps indeed > > could start with a warning? > > I would start with: > > --- a/drivers/media/v4l2-core/v4l2-device.c > +++ b/drivers/media/v4l2-core/v4l2-device.c > @@ -117,6 +117,13 @@ int __v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, > if (!v4l2_dev || !sd || sd->v4l2_dev || !sd->name[0]) > return -EINVAL; > > + /* > + * Initializing sd->dev is mandatory. Warn for now to give faulty > + * drivers a bit of time to update before actually returning an error. > + */ > + WARN_ON(!sd->dev); > + > /* > * The reason to acquire the module here is to avoid unloading > * a module of sub-device which is registered to a media > > Would you like a patch ? Please. :-) -- Kind regards, Sakari Ailus