From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 98F747478; Wed, 19 Aug 2026 04:26:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787113594; cv=none; b=PT3N3spi001ZSGY6YJ+u/DXON8yU+lepA0UDHA/FwkesoCTxR4PHcZMelcrBTWVqag8JWt4fJHmxMwhKLlO+UnGIgCgPoc70ARTbH51+5chDkV8et58WrU2JgelXvBhto0HedfG6bG+sWOhtO1tcm982qUGUCK9rlT6Dd8BAquk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787113594; c=relaxed/simple; bh=3dH4ROXMXeRGiQcvakgSxCQUsQkqrvfrA28UZGtGVVk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=X1YBy8hRH45xPImhn8U9v3/q8lE3PjA5czi5z5AsdRXA9yPHu1jZuxYHJYwAQUSIE+BfZNWnfo1PzadQo4QrCMPuxk7jC4jTAtxTr3zuEMS76BJI7hjJr1kE8ASm+tdTqdPOE0V2lPOFGUzVnlMGJkotPcNCG/uEQOC0FlxhDi0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HP/FhzWr; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="HP/FhzWr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A0051F000E9; Wed, 19 Aug 2026 04:26:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787113593; bh=ErXhuF7Ai0HjSZoqnrXxUkmbIHJi9H6R6PaXpZbpqo8=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=HP/FhzWrZM/gW/b1/4S+hPZV/UUhvHOVRU9y/oPMh6xm+RSso2zgpuDCOdv845s8H rXfygICJPI8sGR2CL4dH8vioHozWiQxCYfBYpaLqs3KG1PXEMV6v3kmf9ygq5jTku7 c3ylCiMuymfYijX0bgI/IN2ESNyB9WWOLUbJuHUjoBssfOMQpSLrIyOOXSzAZuy4gv 2H/IVWznWIF9S6/mRJw1r149c+jRhd8OwJW2aE7fQro71BjEpIVVDi0Ep4AiHIPluC 6tkGckiALH3WNje2xGiVdoEFX0wkfaC+T8uZxfd9aXTwBHUjS825qJQjXvEhq91ScI S6gg6txu8064Q== Message-ID: <46936686-3bdd-4d36-9124-e8d3376ad5ea@kernel.org> Date: Wed, 19 Aug 2026 06:26:28 +0200 Precedence: bulk X-Mailing-List: imx@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] serial: imx: cancel RS485 trigger hrtimers in shutdown and remove To: Fan Wu , Greg Kroah-Hartman Cc: Frank Li , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, stable@vger.kernel.org References: <20260819021916.442827-1-fanwu01@zju.edu.cn> Content-Language: en-US From: Jiri Slaby Autocrypt: addr=jirislaby@kernel.org; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 19. 08. 26, 4:19, Fan Wu wrote: > The rs485 delay hrtimers trigger_start_tx and trigger_stop_tx are > embedded in the devm allocated struct imx_port, and their callbacks > reach the port through container_of() and touch registers under the > port lock. Nothing cancels them synchronously: the tx paths only > call hrtimer_try_to_cancel(), which does not wait for a running > callback, and the bounded wait in imx_uart_shutdown() can give up, > force tx_state to OFF, and leave a timer armed. After > imx_uart_remove() returns, devm frees the port and a late callback > dereferences freed memory. > > Cancel both timers at the end of imx_uart_shutdown(), after the port > lock is dropped and before the clocks are disabled, and again in > imx_uart_remove() before the devm free: > serial core does not call the > driver shutdown on every path that reaches remove(). Could you be more specific on what path it does not? thanks, -- js suse labs