linux-kernel - [PATCH 7/7] regulator: remove superfluous lock in regulator_resolve

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Date:   Tue, 11 Aug 2020 03:07:41 +0200
From:   Michał Mirosław <mirq-linux@...e.qmqm.pl>
To:     Dmitry Osipenko <digetx@...il.com>,
        Liam Girdwood <lgirdwood@...il.com>,
        Mark Brown <broonie@...nel.org>
Cc:     linux-kernel@...r.kernel.org, Vladimir Zapolskiy <vz@...ia.com>
Subject: [PATCH 7/7] regulator: remove superfluous lock in
 regulator_resolve_coupling()

The code modifies rdev, but locks c_rdev instead. The bug remains:
stored c_rdev could be freed just after unlock anyway. This doesn't blow
up because regulator_list_mutex taken outside holds it together.

Signed-off-by: Michał Mirosław <mirq-linux@...e.qmqm.pl>
---
 drivers/regulator/core.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index b85ec974944e..f8834559a2fb 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -4942,13 +4942,9 @@ static void regulator_resolve_coupling(struct regulator_dev *rdev)
 			return;
 		}
 
-		regulator_lock(c_rdev);
-
 		c_desc->coupled_rdevs[i] = c_rdev;
 		c_desc->n_resolved++;
 
-		regulator_unlock(c_rdev);
-
 		regulator_resolve_coupling(c_rdev);
 	}
 }
-- 
2.20.1