From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756715AbbLBUL4 (ORCPT ); Wed, 2 Dec 2015 15:11:56 -0500 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:58044 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755901AbbLBULE (ORCPT ); Wed, 2 Dec 2015 15:11:04 -0500 From: Mark Brown To: Mark Brown , Arnd Bergmann , Thierry Reding , Mark Brown Cc: linux-kernel@vger.kernel.org In-Reply-To: Message-Id: Date: Wed, 02 Dec 2015 20:10:55 +0000 X-SA-Exim-Connect-IP: 94.175.94.161 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Applied "regulator: core: Fix nested locking of supplies" to the regulator tree X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The patch regulator: core: Fix nested locking of supplies has been applied to the regulator tree at git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >>From 70a7fb80e85ae7f78f8e90cec3fbd862ea6a4d4b Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Wed, 2 Dec 2015 16:54:50 +0100 Subject: [PATCH] regulator: core: Fix nested locking of supplies Commit fa731ac7ea04 ("regulator: core: avoid unused variable warning") introduced a subtle change in how supplies are locked. Where previously code was always locking the regulator of the current iteration, the new implementation only locks the regulator if it has a supply. For any given power tree that means that the root will never get locked. On the other hand the regulator_unlock_supply() will still release all the locks, which in turn causes the lock debugging code to warn about a mutex being unlocked which wasn't locked. Cc: Mark Brown Cc: Arnd Bergmann Fixes: Fixes: fa731ac7ea04 ("regulator: core: avoid unused variable warning") Signed-off-by: Thierry Reding Signed-off-by: Mark Brown --- drivers/regulator/core.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index f71db02fcb71..732ac71b82cd 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -132,6 +132,14 @@ static bool have_full_constraints(void) return has_full_constraints || of_have_populated_dt(); } +static inline struct regulator_dev *rdev_get_supply(struct regulator_dev *rdev) +{ + if (rdev && rdev->supply) + return rdev->supply->rdev; + + return NULL; +} + /** * regulator_lock_supply - lock a regulator and its supplies * @rdev: regulator source @@ -140,8 +148,7 @@ static void regulator_lock_supply(struct regulator_dev *rdev) { int i; - mutex_lock(&rdev->mutex); - for (i = 1; rdev; rdev = rdev->supply->rdev, i++) + for (i = 0; rdev; rdev = rdev_get_supply(rdev), i++) mutex_lock_nested(&rdev->mutex, i); } -- 2.6.2