Re: [PATCH] tty: synclink_gt: remove broken driver

[Jiri Slaby <jirislaby@kernel.org>]

On 29. 01. 26, 8:51, Ethan Nelson-Moore wrote:
> The synclink_gt driver was marked as broken in commit 426263d5fb40
> ("tty: synclink_gt: mark as BROKEN") in July 2023 because it had severe
> structural problems and there had been no evidence of users since 2016.
> Since then, no meaningful improvements have been made to the driver,
> and it is unlikely that will ever happen due to the lack of interest.
> Drop the driver and references to it in comments and documentation.

Overall, I am all for it, but a few remarks:

> Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
> ---
>   .../userspace-api/ioctl/ioctl-number.rst      |    2 +-
>   arch/powerpc/configs/ppc6xx_defconfig         |    1 -
>   drivers/net/ppp/Kconfig                       |    4 +-
>   drivers/tty/Kconfig                           |   11 +-
>   drivers/tty/Makefile                          |    1 -
>   drivers/tty/n_hdlc.c                          |    7 -
>   drivers/tty/synclink_gt.c                     | 5038 -----------------
>   include/linux/synclink.h                      |   37 -

     vvvvvvvvvvvvvvvvvvvvvvvvvvvvv

>   include/uapi/linux/synclink.h                 |  301 -

Have you checked this is not included in any relevant userspace? How? 
Hints: debian code search, github...

> diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
> index 7232b3544cec..8abedab9fea7 100644
> --- a/Documentation/userspace-api/ioctl/ioctl-number.rst
> +++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
> @@ -271,7 +271,7 @@ Code  Seq#    Include File                                             Comments
>   'm'   00-09  linux/mmtimer.h                                           conflict!
>   'm'   all    linux/mtio.h                                              conflict!
>   'm'   all    linux/soundcard.h                                         conflict!
> -'m'   all    linux/synclink.h                                          conflict!
> +'m'   all    linux/synclink.h                                          Dead since 2026

I would just drop the line, removing one conflicting entry. The letter 
is not going to be dead.

Or is this Dead note some ioctl-number's policy?

> --- a/drivers/tty/n_hdlc.c
> +++ b/drivers/tty/n_hdlc.c
> @@ -4,8 +4,6 @@
>    * Written by Paul Fulghum paulkf@microgate.com
>    * for Microgate Corporation
>    *
> - * Microgate and SyncLink are registered trademarks of Microgate Corporation
> - *
>    * Adapted from ppp.c, written by Michael Callahan <callahan@maths.ox.ac.uk>,
>    *	Al Longyear <longyear@netcom.com>,
>    *	Paul Mackerras <Paul.Mackerras@cs.anu.edu.au>
> @@ -54,11 +52,6 @@
>    * this line discipline (or another line discipline that is frame
>    * oriented such as N_PPP).
>    *
> - * The SyncLink driver (synclink.c) implements both asynchronous
> - * (using standard line discipline N_TTY) and synchronous HDLC
> - * (using N_HDLC) communications, with the latter using the above
> - * conventions.

This paragraph actually talks about long removed synclink.c, removed in:
   a1f714b44e34 tty: Remove redundant synclink driver
But OK, let's kick all the remaining traces of synclinks.
thanks,
-- 
js
suse labs