On Thu, May 26, 2022 at 07:29:20PM +0300, Leon Romanovsky wrote:
> > > + err = mlx5r_umr_post_send(umrc->qp, mkey, &umr_context.cqe, wqe,
> > > + with_data);
> > > + mutex_unlock(&umrc->lock);
> > > + if (err) {
> > > + mlx5_ib_warn(dev, "UMR post send failed, err %d\n",
> > > + err);
> > > + break;
> > > }
> > > +
> > > + wait_for_completion(&umr_context.done);
> >
> > Nor is sleeping under a semaphore.
>
> Not according to the kernel/locking/semaphore.c. Semaphores can sleep
> and the code protected by semaphores can sleep too.
>
> 53 void down(struct semaphore *sem)
> 54 {
> 55 unsigned long flags;
> 56
> 57 might_sleep();
> ....
> 64 }
> 65 EXPORT_SYMBOL(down);
Hum, OK, I am confused
> > And, I'm pretty sure, this entire function is called under a spinlock
> > in some cases.
>
> Can you point to such flow?
It seems like not anymore, or at least I couldn't find a case.
Jason
