From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A3848C0219B for ; Mon, 10 Feb 2025 17:33:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: Content-Transfer-Encoding:Content-Type:MIME-Version:References:In-Reply-To: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=8BWpaX+en9bzlPyCXNv/OsmRVq8aUFdsmvGYZd5/M1M=; b=Tm7nArt2TAEcgy Yu6NJZfs7pe3XZkm8DEmwuxLIdB9eLVIzzZmGcJ0Jep0yGMMMRGwoizzFLAV+Ce859h9WOl/cdIu4 D2oSeU9JjLIQH+N4Z+XZSJIXzCJpACzRbcQiNHc2LoB4au0AN+aA/HRlnvkpmjLNYOcvvZ0nt6MXo 5YPpIAYDsFQa7K5M48qPY5rYg+LRU0AB+Pq2u7hwQ1onH9pCB1p0AU907vXtZf8VjLoa9/iu4M2nQ RccrAhby0XzfLTQhpvi84hjewyPauTeevRtBWFLticAgZFxNeSI+GAHow0TbKqhqz30bpYtmD+n1N kZE/Z+o2eLCUQqTl02oQ==; 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x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgdefkeeigecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfitefpfffkpdcuggftfghnshhusghstghrihgsvgenuceurghilhhouhhtmecufedtudenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhepfffhvfevuffkjghfohfogggtgfesthejredtredtvdenucfhrhhomhepnfhutggrucevvghrvghsohhlihcuoehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeeglefffefghefhtddvfeeufeeiveekgffgleekieduteekkeetvdehudekgfdvvdenucffohhmrghinhepsghoohhtlhhinhdrtghomhenucfkphepvdgrtddvmeeijedtmedvtddvtdemvggrtddumegsvgegudemleehvgejmeefgeefmeeludefvgenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpedvrgdtvdemieejtdemvddtvddtmegvrgdtudemsggvgedumeelhegvjeemfeegfeemledufegvpdhhvghlohepsghoohhthidpmhgrihhlfhhrohhmpehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopeefjedprhgtphhtthhopegumhhithhrhidrsggrrhihshhhkhhovheslhhinhgrrhhordhorhhgpdhrtghpthhtohepmhhrihhprghrugeskhgvrhhnvghlrdhorhhgpdhrtghpthhtohepshhimhhonhgrsehffhiflhhlrdgthhdpr hgtphhtthhopehinhhkihdruggrvgesshgrmhhsuhhnghdrtghomhdprhgtphhtthhopehjrghgrghnsegrmhgrrhhulhgrshholhhuthhiohhnshdrtghomhdprhgtphhtthhopehmrdhsiiihphhrohifshhkihesshgrmhhsuhhnghdrtghomhdprhgtphhtthhopegtrghtrghlihhnrdhmrghrihhnrghssegrrhhmrdgtohhmpdhrtghpthhtohepfihilhhlsehkvghrnhgvlhdrohhrgh X-GND-Sasl: luca.ceresoli@bootlin.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250210_091253_858219_1F464E94 X-CRM114-Status: GOOD ( 14.96 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexandre Belloni , =?UTF-8?B?SGVy?= =?UTF-8?B?dsOp?= Codina , Thomas Petazzoni , linux-doc@vger.kernel.org, Catalin Marinas , Paul Kocialkowski , dri-devel@lists.freedesktop.org, Claudiu Beznea , Laurent Pinchart , Andrzej Hajda , David Airlie , Fabio Estevam , Marek Szyprowski , Simona Vetter , Robert Foss , Jonathan Corbet , Sam Ravnborg , Jernej Skrabec , Daniel Thompson , Jagan Teki , Jessica Zhang , Thomas Zimmermann , Will Deacon , Jonas Karlman , Sascha Hauer , Maarten Lankhorst , Inki Dae , linux-arm-kernel@lists.infradead.org, Neil Armstrong , Boris Brezillon , linux-kernel@vger.kernel.org, Paul Kocialkowski , Pengutronix Kernel Team , Shawn Guo Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Maxime, Dmitry On Fri, 7 Feb 2025 21:54:06 +0200 Dmitry Baryshkov wrote: > > > +/* Internal function (for refcounted bridges) */ > > > +void __drm_bridge_free(struct kref *kref) > > > +{ > > > + struct drm_bridge *bridge = container_of(kref, struct drm_bridge, refcount); > > > + void *container = ((void *)bridge) - bridge->container_offset; > > > + > > > + DRM_DEBUG("bridge=%p, container=%p FREE\n", bridge, container); > > > > Pointers are not really useful to track here, since they are obfuscated > > most of the time. Using the bridge device name would probably be better > > (or removing the SHOUTING DEBUG entirely :)) > > bridge device name or bridge funcs (I opted for the latter for the > debugfs file) These DRM_DEBUG()s proved extremely useful exactly because of the pointer. This is because when using hotplug one normally has the same device added and removed multiple times, and so the device name or bridge funcs is always the same, preventing from understanding which instance is leaking, or being freed, get, put, etc. Do you think this is a sufficient motivation to keep it? Luca -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com