From patchwork Mon Dec 4 18:05:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: George Stark X-Patchwork-Id: 750901 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=salutedevices.com header.i=@salutedevices.com header.b="uhrUXJip" Received: from mx1.sberdevices.ru (mx2.sberdevices.ru [45.89.224.132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4B08EFF; Mon, 4 Dec 2023 10:07:13 -0800 (PST) Received: from p-infra-ksmg-sc-msk02 (localhost [127.0.0.1]) by mx1.sberdevices.ru (Postfix) with ESMTP id C9100120015; Mon, 4 Dec 2023 21:07:10 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.sberdevices.ru C9100120015 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=salutedevices.com; s=mail; t=1701713230; bh=2odVOM9BnkWCbIAdrFB9FbwUfhyeUbvi+YVzHb6e/sU=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type:From; b=uhrUXJipaXGYfVT73+HL9DJgULCzGID9RZhkeIk3XZZj0FJvs/6+VXnYlmDqO9mlW kaR/oX8BvDrhQP9yG7l5JJWxJOWhL3v/GJc/JzSoaBv0Itciu2axBKy3GkZhacsvoT hzE5AzoQQrvHWOqwZmnCZhTM/hNGFvdPrMwLnSlkRDncWG3QTBiQ6Hlcl9iPxy4XTW EzLrLtpXEOGZ35KY5Mf5slq8GwF/3WP6QzQNpC6lu7PhVec0DaNXB+++Amv8qVLIkb x70MVxpA4jPrqs8LjGUq+DtVUBfl2/zize5/IXd7rKM69E4KPrZ/gZ4F8qzHKSDGTU EvPOjO6Lq95KQ== Received: from p-i-exch-sc-m01.sberdevices.ru (p-i-exch-sc-m01.sberdevices.ru [172.16.192.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.sberdevices.ru (Postfix) with ESMTPS; Mon, 4 Dec 2023 21:07:10 +0300 (MSK) Received: from localhost.localdomain (100.64.160.123) by p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Mon, 4 Dec 2023 21:07:10 +0300 From: George Stark To: , , , , , , , , , CC: , , , , George Stark Subject: [PATCH v2 00/10] devm_led_classdev_register() usage problem Date: Mon, 4 Dec 2023 21:05:53 +0300 Message-ID: <20231204180603.470421-1-gnstark@salutedevices.com> X-Mailer: git-send-email 2.42.0 Precedence: bulk X-Mailing-List: linux-leds@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) To p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) X-KSMG-Rule-ID: 10 X-KSMG-Message-Action: clean X-KSMG-AntiSpam-Lua-Profiles: 181831 [Dec 04 2023] X-KSMG-AntiSpam-Version: 6.0.0.2 X-KSMG-AntiSpam-Envelope-From: gnstark@salutedevices.com X-KSMG-AntiSpam-Rate: 0 X-KSMG-AntiSpam-Status: not_detected X-KSMG-AntiSpam-Method: none X-KSMG-AntiSpam-Auth: dkim=none X-KSMG-AntiSpam-Info: LuaCore: 5 0.3.5 98d108ddd984cca1d7e65e595eac546a62b0144b, {Tracking_uf_ne_domains}, {Tracking_urls_end_caps}, {Tracking_from_domain_doesnt_match_to}, d41d8cd98f00b204e9800998ecf8427e.com:7.1.1; 100.64.160.123:7.1.2; p-i-exch-sc-m01.sberdevices.ru:7.1.1,5.0.1; 127.0.0.199:7.1.2; salutedevices.com:7.1.1; lore.kernel.org:7.1.1, FromAlignment: s, ApMailHostAddress: 100.64.160.123 X-MS-Exchange-Organization-SCL: -1 X-KSMG-AntiSpam-Interceptor-Info: scan successful X-KSMG-AntiPhishing: Clean, bases: 2023/12/04 17:37:00 X-KSMG-LinksScanning: Clean, bases: 2023/12/04 17:37:00 X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 2.0.1.6960, bases: 2023/12/04 11:06:00 #22624476 X-KSMG-AntiVirus-Status: Clean, skipped This patch series fixes the problem of devm_led_classdev_register misusing. The basic problem is described in [1]. Shortly when devm_led_classdev_register() is used then led_classdev_unregister() called after driver's remove() callback. led_classdev_unregister() calls driver's brightness_set callback and that callback may use resources which were destroyed already in driver's remove(). After discussion with maintainers [2] [3] we decided: 1) don't touch led subsytem core code and don't remove led_set_brightness() from it but fix drivers 2) don't use devm_led_classdev_unregister So the solution is to use devm wrappers for all resources driver's brightness_set() depends on. And introduce dedicated devm wrapper for mutex as it's often used resource. [1] https://lore.kernel.org/lkml/8704539b-ed3b-44e6-aa82-586e2f895e2b@salutedevices.com/T/ [2] https://lore.kernel.org/lkml/8704539b-ed3b-44e6-aa82-586e2f895e2b@salutedevices.com/T/#mc132b9b350fa51931b4fcfe14705d9f06e91421f [3] https://lore.kernel.org/lkml/8704539b-ed3b-44e6-aa82-586e2f895e2b@salutedevices.com/T/#mdbf572a85c33f869a553caf986b6228bb65c8383 George Stark (10): devm-helpers: introduce devm_mutex_init leds: aw2013: unlock mutex before destroying it leds: aw2013: use devm API to cleanup module's resources leds: aw200xx: use devm API to cleanup module's resources leds: lp3952: use devm API to cleanup module's resources leds: lm3532: use devm API to cleanup module's resources leds: nic78bx: use devm API to cleanup module's resources leds: mlxreg: use devm_mutex_init for mutex initializtion leds: an30259a: use devm_mutext_init for mutext initialization leds: powernv: add LED_RETAIN_AT_SHUTDOWN flag for leds drivers/leds/leds-an30259a.c | 14 ++++---------- drivers/leds/leds-aw200xx.c | 36 +++++++++++++++++++++++++----------- drivers/leds/leds-aw2013.c | 28 ++++++++++++++++------------ drivers/leds/leds-lm3532.c | 29 +++++++++++++++++------------ drivers/leds/leds-lp3952.c | 21 +++++++++++---------- drivers/leds/leds-mlxreg.c | 15 ++++----------- drivers/leds/leds-nic78bx.c | 25 +++++++++++++------------ drivers/leds/leds-powernv.c | 23 ++++++++--------------- include/linux/devm-helpers.h | 18 ++++++++++++++++++ 9 files changed, 116 insertions(+), 93 deletions(-) --- 2.38.4