Re: [PATCH v3 1/8] tty: n_gsm: add restart parameter to DLC specific ioctl config

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Apr 24, 2023 at 11:03:26AM +0000, Starke, Daniel wrote:
> > > --- a/include/uapi/linux/gsmmux.h
> > > +++ b/include/uapi/linux/gsmmux.h
> > > @@ -58,7 +58,8 @@ struct gsm_dlci_config {
> > >  	__u32 priority;		/* Priority (0 for default value) */
> > >  	__u32 i;		/* Frame type (1 = UIH, 2 = UI) */
> > >  	__u32 k;		/* Window size (0 for default value) */
> > > -	__u32 reserved[8];	/* For future use, must be initialized to zero */
> > > +	__u32 restart;		/* Force DLCI channel reset? */
> > 
> > Why are you using a full 32 bits for just 1 bit of data here?  Why not
> > use a bitfield?
> 
> The ioctrl guide states:
>   Bitfields and enums generally work as one would expect them to,
>   but some properties of them are implementation-defined, so it is better
>   to avoid them completely in ioctl interfaces.
> 
> Therefore, I tried to avoid them here.

Then use a u8?

> > And what happened to the request to turn the documentation for this
> > structure into proper kerneldoc format?
> 
> That applied to patch 2/8 and is unrelated to this patch. Another patch
> will need to fix this.
> 
> Link: https://lore.kernel.org/all/20230424075251.5216-2-daniel.starke@siemens.com/

It's kind of related in that the format is not right :)

As it's a few weeks before I am allowed to even apply this, please
rework the series a bit.

thanks,

greg k-h