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Add this to catch the problem in the future. Signed-off-by: Ahmed Ehab --- lib/locking-selftest.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c index 6f6a5fc85b42..0783ee97c971 100644 --- a/lib/locking-selftest.c +++ b/lib/locking-selftest.c @@ -2710,6 +2710,44 @@ static void local_lock_3B(void) } +#if CONFIG_DEBUG_LOCK_ALLOC +static inline const char *rw_semaphore_lockdep_name(struct rw_semaphore *rwsem) +{ + return rwsem->dep_map.name; +} +#else +static inline const char *rw_semaphore_lockdep_name(struct rw_semaphore *rwsem) +{ + return NULL; +} +#endif + +static void lock_class_subclass_X1(void) +{ + const char *name_before_setting_subclass = rw_semaphore_lockdep_name(&rwsem_X1); + const char *name_after_setting_subclass; + + lockdep_set_subclass(&rwsem_X1, 1); + name_after_setting_subclass = rw_semaphore_lockdep_name(&rwsem_X1); + DEBUG_LOCKS_WARN_ON(name_before_setting_subclass != name_after_setting_subclass); +} + +/* + * after setting the subclass the lockdep_map.name changes + * if we initialize a new string literal for the subclass + * we will have a new name pointer + */ +static void class_subclass_X1_name_test(void) +{ + printk(" --------------------------------------------------------------------------\n"); + printk(" | class and subclass name test|\n"); + printk(" ---------------------\n"); + + print_testname("lock class and subclass same name"); + dotest(lock_class_subclass_X1, SUCCESS, LOCKTYPE_RWSEM); + pr_cont("\n"); +} + static void local_lock_tests(void) { printk(" --------------------------------------------------------------------------\n"); @@ -2920,6 +2958,8 @@ void locking_selftest(void) dotest(hardirq_deadlock_softirq_not_deadlock, FAILURE, LOCKTYPE_SPECIAL); pr_cont("\n"); + class_subclass_X1_name_test(); + if (unexpected_testcase_failures) { printk("-----------------------------------------------------------------\n"); debug_locks = 0; -- 2.46.0