On Thu, 21 Sep 2017 18:43:02 +0200 Sebastian Andrzej Siewior <bige...@linutronix.de> wrote:
> On 2017-09-21 12:31:05 [-0400], Steven Rostedt wrote: > > > diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c > > > index f03876322d4a..79f49d73e4d0 100644 > > > --- a/kernel/locking/rtmutex.c > > > +++ b/kernel/locking/rtmutex.c > > > @@ -2281,7 +2281,6 @@ int __rt_mutex_start_proxy_lock(struct rt_mutex > > > *lock, > > > raw_spin_lock(&task->pi_lock); > > > if (task->pi_blocked_on) { > > > raw_spin_unlock(&task->pi_lock); > > > - raw_spin_unlock_irq(&lock->wait_lock); > > > > Hmm, before this patch, irqs are enabled when returning with -EAGAIN. > > But now they are not. Should that be: > > > > raw_spin_unlock_irq(&taks->pi_lock); > > > > or is there something that changes this? > > There is something else. Before that futex rework there was just > rt_mutex_start_proxy_lock() and it did lock & unlock of ->wait_lock. > This no longer the case after the rework. So now the caller does this. > So this actually fixes two bugs then? Anyway, probably want to add that in the change log to explain why it is ok to change the irq semantics here too. Thanks! -- Steve