The rwlock is spinning while acquiring a lock. Therefore it must become a sleeping lock on RT and preserve its task state while sleeping and waiting for the lock. Reported-by: Joe Korty <Joe.Korty@xxxxxxxxxxxxxxxxx> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> --- kernel/locking/rwlock-rt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/locking/rwlock-rt.c b/kernel/locking/rwlock-rt.c index f2e155b2c4a8b..c3b91205161cc 100644 --- a/kernel/locking/rwlock-rt.c +++ b/kernel/locking/rwlock-rt.c @@ -128,7 +128,7 @@ void __sched __read_rt_lock(struct rt_rw_lock *lock) * That would put Reader1 behind the writer waiting on * Reader2 to call read_unlock() which might be unbound. */ - rt_mutex_init_waiter(&waiter, false); + rt_mutex_init_waiter(&waiter, true); rt_spin_lock_slowlock_locked(m, &waiter, flags); /* * The slowlock() above is guaranteed to return with the rtmutex is -- 2.20.1