Some kernel module options not showing up in modinfo

Some kernel module options not showing up in modinfo

[Raphael Hertzog]

Hello,

I noticed that some options are not visible in the modinfo output. For
instance "modinfo lockd" reports this on my Debian sid system:

$ modinfo lockd
filename:       /lib/modules/3.11-1-amd64/kernel/fs/lockd/lockd.ko
license:        GPL
description:    NFS file locking service version 0.5.
author:         Olaf Kirch <okir@monad.swb.de>
depends:        sunrpc
intree:         Y
vermagic:       3.11-1-amd64 SMP mod_unload modversions 
parm:           nsm_use_hostnames:bool
parm:           nlm_max_connections:uint
$

Yet I know that there are more options and the kernel source code confirms
this:
http://lxr.free-electrons.com/source/fs/lockd/svc.c#L569

Multiple other options are defined by way of module_param_call(...) like
nlm_grace_period, nlm_timeout, nlm_updport, nlm_tcpport.

Ben Hutchings (one of the Debian kernel maintainers) confirmed me that
this was unexpected and suggested me to report it to you. If you have any
questions, just ask.

Cheers,
-- 
Raphaël Hertzog ◈ Debian Developer

Discover the Debian Administrator's Handbook:
→ http://debian-handbook.info/get/

Re: Some kernel module options not showing up in modinfo

[Rusty Russell]

Raphael Hertzog <hertzog@debian.org> writes:
> Hello,
>
> I noticed that some options are not visible in the modinfo output. For
> instance "modinfo lockd" reports this on my Debian sid system:
>
> $ modinfo lockd
> filename:       /lib/modules/3.11-1-amd64/kernel/fs/lockd/lockd.ko
> license:        GPL
> description:    NFS file locking service version 0.5.
> author:         Olaf Kirch <okir@monad.swb.de>
> depends:        sunrpc
> intree:         Y
> vermagic:       3.11-1-amd64 SMP mod_unload modversions 
> parm:           nsm_use_hostnames:bool
> parm:           nlm_max_connections:uint
> $
>
> Yet I know that there are more options and the kernel source code confirms
> this:
> http://lxr.free-electrons.com/source/fs/lockd/svc.c#L569
>
> Multiple other options are defined by way of module_param_call(...) like
> nlm_grace_period, nlm_timeout, nlm_updport, nlm_tcpport.
>
> Ben Hutchings (one of the Debian kernel maintainers) confirmed me that
> this was unexpected and suggested me to report it to you. If you have any
> questions, just ask.

Yes, the module_param() macro adds a type description.  The
module_param_call() does not.

Hope that helps,
Rusty.

Re: Some kernel module options not showing up in modinfo

[Raphael Hertzog]

Hi,

On Fri, 22 Nov 2013, Rusty Russell wrote:
> Raphael Hertzog <hertzog@debian.org> writes:
> > Hello,
> >
> > I noticed that some options are not visible in the modinfo output. For
> > instance "modinfo lockd" reports this on my Debian sid system:
[...]
> > Multiple other options are defined by way of module_param_call(...) like
> > nlm_grace_period, nlm_timeout, nlm_updport, nlm_tcpport.
> 
> Yes, the module_param() macro adds a type description.  The
> module_param_call() does not.

Couldn't they be displayed without any type or with a type "unknown" ?

parm: nlm_grace_period

or 

parm: nlm_grace_period:unknown

Cheers,
-- 
Raphaël Hertzog ◈ Debian Developer

Discover the Debian Administrator's Handbook:
→ http://debian-handbook.info/get/

Re: Some kernel module options not showing up in modinfo

[Rusty Russell]

Raphael Hertzog <hertzog@debian.org> writes:
> Hi,
>
> On Fri, 22 Nov 2013, Rusty Russell wrote:
>> Raphael Hertzog <hertzog@debian.org> writes:
>> > Hello,
>> >
>> > I noticed that some options are not visible in the modinfo output. For
>> > instance "modinfo lockd" reports this on my Debian sid system:
> [...]
>> > Multiple other options are defined by way of module_param_call(...) like
>> > nlm_grace_period, nlm_timeout, nlm_updport, nlm_tcpport.
>> 
>> Yes, the module_param() macro adds a type description.  The
>> module_param_call() does not.
>
> Couldn't they be displayed without any type or with a type "unknown" ?
>
> parm: nlm_grace_period
>
> or 
>
> parm: nlm_grace_period:unknown

The type thing is really a hack.  Ideally we should force documentation
on everyone who declares a module parameter with a new macro we can
transition to.

Of course, most descriptions would be incoherent, a-la Kbuild help
messages, so we'd need an enforcer...

Rusty.