From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=salutedevices.com header.i=@salutedevices.com header.b="GhGjBEAF" Received: from mx1.sberdevices.ru (mx2.sberdevices.ru [45.89.224.132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA5D0CF; Thu, 14 Dec 2023 09:36:25 -0800 (PST) Received: from p-infra-ksmg-sc-msk02 (localhost [127.0.0.1]) by mx1.sberdevices.ru (Postfix) with ESMTP id 5D93B12000A; Thu, 14 Dec 2023 20:36:24 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.sberdevices.ru 5D93B12000A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=salutedevices.com; s=mail; t=1702575384; bh=FF/GGxCAQiFT7arMrSkuCqDAuMbQap2zzePwvbnW2V0=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type:From; b=GhGjBEAFfoGiNP+ktkmQVcfzKTI392HOS4Qs7+mmOSFpj8bGuA79iWxZUwTv9nyMh sNpAHk27qFX0dwuTI5BORL94+mIyqTKROgXFJ2CPaHJ4bXTpFAZEjjoASM1JMNTXbh 3THcDPSVy8VFD4mnzC1C8eFC8Ii/3eeiuVWYGgcg1UHOcM2Ve2NJqg7I9ZwVcRbUtn kDc5pede4ba6ZMbbpgC7gRvfM9p1VSENJJXcHLtY/H9Dt+/SXGFeQucOt5ELXPwcXz xBe0Asub0gS+b/VIZxNMG3TXSonYWblQ0TQw7QRc2zf30qHv4zdBKwe61vSULf295N gd4UDmhnLRklg== Received: from smtp.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; Thu, 14 Dec 2023 20:36:24 +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; Thu, 14 Dec 2023 20:36:23 +0300 From: George Stark To: , , , , , , , , , , , , , , CC: , , , , George Stark Subject: [PATCH v4 00/10] devm_led_classdev_register() usage problem Date: Thu, 14 Dec 2023 20:36:04 +0300 Message-ID: <20231214173614.2820929-1-gnstark@salutedevices.com> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-leds@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: p-i-exch-sc-m02.sberdevices.ru (172.16.192.103) 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: 182125 [Dec 14 2023] X-KSMG-AntiSpam-Version: 6.1.0.3 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: 7 0.3.7 6d6bf5bd8eea7373134f756a2fd73e9456bb7d1a, {Tracking_uf_ne_domains}, {Tracking_urls_end_caps}, {Tracking_from_domain_doesnt_match_to}, salutedevices.com:7.1.1;smtp.sberdevices.ru:5.0.1,7.1.1;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;lore.kernel.org:7.1.1;100.64.160.123:7.1.2;127.0.0.199:7.1.2, 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: 2023/12/14 14:24:00 X-KSMG-LinksScanning: Clean, bases: 2023/12/14 14:25:00 X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 2.0.1.6960, bases: 2023/12/14 10:50:00 #22693095 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 Changelog: v1->v2: revise patch series completely v2->v3: locking: add define if mutex_destroy() is not an empty function new patch, discussed here [8] devm-helpers: introduce devm_mutex_init previous version [4] - revise code based on mutex_destroy define - update commit message - update devm_mutex_init()'s description leds: aw2013: unlock mutex before destroying it previous version [5] - make this patch first in the series - add tags Fixes and RvB by Andy leds: aw2013: use devm API to cleanup module's resources previous version [6] - make aw2013_chip_disable_action()'s body oneline - don't shadow devm_mutex_init() return code leds: aw200xx: use devm API to cleanup module's resources previous version [7] - make aw200xx_*_action()'s bodies oneline - don't shadow devm_mutex_init() return code 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 - those pathes were planned but not sent in the series #2 due to mail server problem on my side. I revised them according to the comments. v3->v4: locking: introduce devm_mutex_init new patch - move devm_mutex_init implementation completely from devm-helpers.h to mutex.h locking: add define if mutex_destroy() is not an empty function drop the patch [9] devm-helpers: introduce devm_mutex_init drop the patch [10] leds: aw2013: use devm API to cleanup module's resources - add tag Tested-by: Nikita Travkin [4] https://lore.kernel.org/lkml/20231204180603.470421-1-gnstark@salutedevices.com/T/#mf500af0eda2a9ffc95594607dbe4cb64f2e3c9a8 [5] https://lore.kernel.org/lkml/20231204180603.470421-1-gnstark@salutedevices.com/T/#mc92df4fb4f7d4187fb01cc1144acfa5fb5230dd2 [6] https://lore.kernel.org/lkml/20231204180603.470421-1-gnstark@salutedevices.com/T/#m300df89710c43cc2ab598baa16c68dd0a0d7d681 [7] https://lore.kernel.org/lkml/20231204180603.470421-1-gnstark@salutedevices.com/T/#m8e5c65e0c6b137c91fa00bb9320ad581164d1d0b [8] https://lore.kernel.org/lkml/377e4437-7051-4d88-ae68-1460bcd692e1@redhat.com/T/#m5f84a4a2f387d49678783e652b9e658e02c27450 [9] https://lore.kernel.org/lkml/20231213223020.2713164-1-gnstark@salutedevices.com/T/#m19ad1fc04c560012c1e27418e3156d0c9306dd84 [10] https://lore.kernel.org/lkml/20231213223020.2713164-1-gnstark@salutedevices.com/T/#m63126025f5d1bdcef69bcad50f2e58274d42e2d7 George Stark (10): leds: aw2013: unlock mutex before destroying it locking: introduce devm_mutex_init 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: use LED_RETAIN_AT_SHUTDOWN flag for leds drivers/leds/leds-an30259a.c | 15 +++++---------- drivers/leds/leds-aw200xx.c | 33 ++++++++++++++++++++++----------- drivers/leds/leds-aw2013.c | 27 +++++++++++++++------------ drivers/leds/leds-lm3532.c | 30 ++++++++++++++++++------------ drivers/leds/leds-lp3952.c | 21 +++++++++++---------- drivers/leds/leds-mlxreg.c | 17 ++++++----------- drivers/leds/leds-nic78bx.c | 25 +++++++++++++------------ drivers/leds/leds-powernv.c | 23 ++++++++--------------- include/linux/mutex.h | 23 +++++++++++++++++++++++ kernel/locking/mutex-debug.c | 22 ++++++++++++++++++++++ 10 files changed, 143 insertions(+), 93 deletions(-) -- 2.25.1