3.18.48-rt54-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior Alex Goins reported that mutex_destroy() on RT will force a GPL only symbol which won't link and therefore fail on a non-GPL kernel module. This does not happen on !RT and is a regression on RT which we would like to avoid. I try here the easy thing and to not use rt_mutex_destroy() if CONFIG_DEBUG_MUTEXES is not enabled. This will still break for the DEBUG configs so instead of adding a wrapper around rt_mutex_destroy() (which we have for rt_mutex_lock() for instance) I am simply dropping the GPL part from the export. Reported-by: Alex Goins Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Steven Rostedt (VMware) --- include/linux/mutex_rt.h | 5 +++++ kernel/locking/rtmutex.c | 3 +-- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/include/linux/mutex_rt.h b/include/linux/mutex_rt.h index c38a44b14da5..e0284edec655 100644 --- a/include/linux/mutex_rt.h +++ b/include/linux/mutex_rt.h @@ -43,7 +43,12 @@ extern void __lockfunc _mutex_unlock(struct mutex *lock); #define mutex_lock_killable(l) _mutex_lock_killable(l) #define mutex_trylock(l) _mutex_trylock(l) #define mutex_unlock(l) _mutex_unlock(l) + +#ifdef CONFIG_DEBUG_MUTEXES #define mutex_destroy(l) rt_mutex_destroy(&(l)->lock) +#else +static inline void mutex_destroy(struct mutex *lock) {} +#endif #ifdef CONFIG_DEBUG_LOCK_ALLOC # define mutex_lock_nested(l, s) _mutex_lock_nested(l, s) diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 8d950b4521fc..89651b3e7700 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -2018,8 +2018,7 @@ void rt_mutex_destroy(struct rt_mutex *lock) lock->magic = NULL; #endif } - -EXPORT_SYMBOL_GPL(rt_mutex_destroy); +EXPORT_SYMBOL(rt_mutex_destroy); /** * __rt_mutex_init - initialize the rt lock -- 2.10.2