Re: [PATCH v1] s390/virtio_ccw: Also suppress -EINVAL on device detach

[Halil Pasic <pasic@linux.ibm.com>]

On Fri, 12 Jun 2026 17:54:07 +0200
William Bezenah <wbezenah@linux.ibm.com> wrote:

> Since commit 8c58a229688c ("s390/cio: Do not unregister the
> subchannel based on DNV"), subchannel behavior following a device
> detach has been updated and results in -EINVAL being propagated
> rather than -ENODEV, originating from ccw_device_start_timeout_key()
> in cio/device_ops. In the end, the virtio driver has no ability to
> react to the difference between device and subchannel states here,
> and during detach, both -ENODEV and -EINVAL indicate the device
> cannot be used and should not be treated as errors requiring
> attention. Update error handling in virtio_ccw_del_vq() and
> virtio_ccw_drop_indicator() to suppress -EINVAL in addition to
> -ENODEV.

Hi William!

Are you saying that ccw_device_start() started returning -EINVAL
since 8c58a229688c ("s390/cio: Do not unregister the subchannel based on
DNV")? Or did I somehow read the paragraph wrong?

The funcition ccw_device_start is documented to return:
 * Returns:                                                                     
 *  %0, if the operation was successful;                                        
 *  -%EBUSY, if the device is busy, or status pending;                          
 *  -%EACCES, if no path specified in @lpm is operational;                      
 *  -%ENODEV, if the device is not operational. 
and the commit message does not say a thing about introducing -EINVAL to
the mix.

Regards,
Halil