On Thu, May 26, 2022 at 02:21:32PM -0300, Jason Gunthorpe wrote:
> 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.
So are we fine with this patch and it can go as is after merge window?
Thanks
>
> Jason
