Re: ynl newbie question

Re: ynl newbie question

[Jakub Kicinski]

On Fri, 24 Oct 2025 13:39:57 +0000 Ratheesh Kannoth wrote:
> HI List,
> 
> Followed.
> https://docs.kernel.org/userspace-api/netlink/intro-specs.html
> 
> But I get following error.
> 
> root@rkannoth-OptiPlex-7090:~/linux# ./tools/net/ynl/pyynl/cli.py --spec Documentation/netlink/specs/ethtool.yaml       --do rings-get       --json '{"header":{"dev-index": 18}}'
>   File "./tools/net/ynl/pyynl/cli.py", line 19
>     schema_dir = os.path.abspath(f"{script_dir}/{relative_schema_dir}")
>                                                                      ^
> 
> Should I install anything ? there is no "/usr/share/ynl" directory
> (code cloned  from  https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git)

I think you trimmed the stack trace a little too much?

But my guess if you're having issues with the schema is Python support
for jsonschema.

BTW if you're using Fedora ynl is part of kernel-tools.
Not sure if it propagated to RHEL/CentOS yet.

Re: Re: ynl newbie question

[Ratheesh Kannoth]

From: Jakub Kicinski <kuba@kernel.org> 
Subject: [EXTERNAL] Re: ynl newbie question

>I think you trimmed the stack trace a little too much?

Below is the full output.

#########################################
root@localhost:~/linux# ./tools/net/ynl/pyynl/cli.py --spec Documentation/netlink/specs/ethtool.yaml       --do rings-get       --json '{"header":{"dev-index": 18}}'
  File "./tools/net/ynl/pyynl/cli.py", line 23
    raise Exception(f"Schema directory {schema_dir} does not exist")
                                                                  ^
SyntaxError: invalid syntax
#################################


>But my guess if you're having issues with the schema is Python support
>for jsonschema.
I agree. But not getting any clue from the output error.

I see this issue in a  rootfs which is created out of  ubunutu xenial.  I have installed jsonschema here.
I don’t think it is an issue with ubuntu as I could execute command on my workstation (Which is running ubuntu noble, see output).

#################
rkannoth@rkannoth-OptiPlex-7090:/mnt$ sudo ./ubuntu-rootfs/root/linux/./tools/net/ynl/pyynl/cli.py --spec ./ubuntu-rootfs/root/linux/Documentation/netlink/specs/ethtool.yaml       --do rings-get       --json '{"header":{"dev-index":
 18}}'
Netlink error: No such device
nl_len = 76 (60) nl_flags = 0x300 nl_type = 2
        error: -19
        extack: {'msg': 'no device matches ifindex', 'bad-attr': '.header.dev-index'}

#################

-Ratheesh

Re: ynl newbie question

[Donald Hunter]

Ratheesh Kannoth <rkannoth@marvell.com> writes:

> From: Jakub Kicinski <kuba@kernel.org> 
> Subject: [EXTERNAL] Re: ynl newbie question
>
>>I think you trimmed the stack trace a little too much?
>
> Below is the full output.
>
> #########################################
> root@localhost:~/linux# ./tools/net/ynl/pyynl/cli.py --spec Documentation/netlink/specs/ethtool.yaml       --do rings-get       --json '{"header":{"dev-index": 18}}'
>   File "./tools/net/ynl/pyynl/cli.py", line 23
>     raise Exception(f"Schema directory {schema_dir} does not exist")
>                                                                   ^
> SyntaxError: invalid syntax
> #################################

Is that an old python that doesn't have f-string support, or something?
Can you tell us the python version you are using?

RE: [EXTERNAL] Re: ynl newbie question

[Ratheesh Kannoth]

From: Donald Hunter <donald.hunter@gmail.com> 
Subject: [EXTERNAL] Re: ynl newbie question

>
>> Below is the full output.
>>
> >#########################################
> >root@localhost:~/linux# ./tools/net/ynl/pyynl/cli.py --spec Documentation/netlink/specs/ethtool.yaml       --do rings-get       --json '{"header":{"dev-index": 18}}'
> >  File "./tools/net/ynl/pyynl/cli.py", line 23
> >    raise Exception(f"Schema directory {schema_dir} does not exist")
> >                                                                 ^
> > SyntaxError: invalid syntax
> > #################################

>Is that an old python that doesn't have f-string support, or something?
>Can you tell us the python version you are using?
Bingo !.  upgraded python and it works. Thanks a ton.