[linux-audio-user] Installing realtime kernel - gentoo ERRORs loading realtime module

[Marc-Olivier Barre]

On 3/25/07, Brad Fuller <brad at sonaural.com> wrote:
> I'm following the directions on the wiki for the RT kernel at:
> http://proaudio.tuxfamily.org/wiki/index.php?title=Realtime_%28RT%29_Kernel
>
> and I'm at the point of modprobe'ing the realtime module in the
> instructions which say:
>
> -----------------
> load realtime-lsm
>
>   # modprobe commoncap
>   # modprobe realtime gid=18
> -----------------
>
> But, I receive this error:
>
> FATAL: Error inserting realtime
> (/lib/modules/2.6.16-rt29-tglx4/extra/realtime.ko): Invalid module format--
>
> when modprobe'ing the "realtime" module.
>
> Why is this?  The kernel and the module were compiled with the same tools.

Hi Brad,

You may have not seen it but on the wiki you pointed to, in the part
called "Activate and test RT" the realtime-lsm module is marked as
deprecated. if you go a little further in the document you will find a
section called "RLIMITS" (right after the realtime-lsm one).

The currently recommended method to get realtime to work is to use the
rlimits method with PAM, which you should normally have on your
system. It will make things a lot easier for you.

The tutorial might be taking some shortcuts (depending on your
configuration). If after following the tutorial's info it still
doesn't work, try the following :

- check that your user is part of the audio group
- from a terminal, type in the following command :
grep "pam_limits.so" /etc/pam.d/{gdm,kdm,xdm,login} 2> /dev/null

you should see lines like this :
/etc/pam.d/login:session     required       pam_limits.so

In this example, the file named /etc/pam.d/login contains the modules
used by pam when you authenticate with the login program. The line
that appeared (normally) on your screen states that the pam_limits.so
module will be used. That's the one you want.

Please give us some feedback on how it went and ask again if it didn't work.

Cheers,
__________________
Marc-Olivier Barre,
Markinoko.