Re: [RFC PATCH 2/2] virtio/s390: fix race in ccw_io_helper()

Cornelia Huck
2018-09-20T10:15:23Z

On Wed, 19 Sep 2018 18:56:45 +0200
Halil Pasic <pasic@linux.ibm.com> wrote:

> On 09/19/2018 04:07 PM, Cornelia Huck wrote:

> > Do you spot any other places where we may need to care about concurrent
> > processing (like for the ->config area in the previous patch)?
> >
>
> It is hard to tell, because:
> * Synchronization external to the transport could make things work
> out just fine.
> * virtio_config_ops does not document these requirements if any.
> * So it's up to the devices to use the stuff without shooting
> themselves in the foot.
> * virtio-pci does not seem to do more to avoid such problems that
> we do.
>
> Back then when learning vritio-ccw I did ask myself such questions
> and based on vrito-pci and I was like looks similar, should be
> good enough.

Yep, I agree. If there's nothing obvious, I think we should just leave
it as it is now.