From f6828e413faa37e2b1366415c97d2315bbbe31d0 Mon Sep 17 00:00:00 2001 From: George Stark Date: Thu, 11 Apr 2024 19:10:25 +0300 Subject: locking/mutex: Introduce devm_mutex_init() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 4cd47222e435dec8e3787614924174f53fcfb5ae ] Using of devm API leads to a certain order of releasing resources. So all dependent resources which are not devm-wrapped should be deleted with respect to devm-release order. Mutex is one of such objects that often is bound to other resources and has no own devm wrapping. Since mutex_destroy() actually does nothing in non-debug builds frequently calling mutex_destroy() is just ignored which is safe for now but wrong formally and can lead to a problem if mutex_destroy() will be extended so introduce devm_mutex_init(). Suggested-by: Christophe Leroy Signed-off-by: George Stark Reviewed-by: Christophe Leroy Reviewed-by: Andy Shevchenko Reviewed-by: Marek Behún Acked-by: Waiman Long Link: https://lore.kernel.org/r/20240411161032.609544-2-gnstark@salutedevices.com Signed-off-by: Lee Jones Stable-dep-of: efc347b9efee ("leds: mlxreg: Use devm_mutex_init() for mutex initialization") Signed-off-by: Sasha Levin --- kernel/locking/mutex-debug.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'kernel/locking/mutex-debug.c') diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c index bc8abb8549d2..6e6f6071cfa2 100644 --- a/kernel/locking/mutex-debug.c +++ b/kernel/locking/mutex-debug.c @@ -12,6 +12,7 @@ */ #include #include +#include #include #include #include @@ -89,6 +90,17 @@ void debug_mutex_init(struct mutex *lock, const char *name, lock->magic = lock; } +static void devm_mutex_release(void *res) +{ + mutex_destroy(res); +} + +int __devm_mutex_init(struct device *dev, struct mutex *lock) +{ + return devm_add_action_or_reset(dev, devm_mutex_release, lock); +} +EXPORT_SYMBOL_GPL(__devm_mutex_init); + /*** * mutex_destroy - mark a mutex unusable * @lock: the mutex to be destroyed -- cgit v1.2.3