[lug] logging missing 2.6 kernel modules

[D. Stimits]

David Anselmi wrote:
> D. Stimits wrote:
> 
>> It used to be that on a 2.4 kernel an attempt to use a device that did 
>> not have a proper kernel driver would yield a message, e.g., something 
>> like "no module for net-pf-10"...I forget that particular one was 
>> something like an apple printer protocol. I'm trying to get the sblive 
>> game port to load automatically on a 2.6 kernel and FC2.
> 
> 
> Not sure I'm much help, but here's what I know.
> 
> Are you using udev?  That's a new way to manage /dev entries--instead of 
> listing everything possible it only lists things that exist (have 
> hardware and have a module).

An interesting thing when looking at the 2.6 Pseudo filesystems menu, it 
shows the option for the old devfs as /dev, and marks it obsolete, which 
I have NOT enabled (I've always avoided devfs like the plague, and do 
not want to use udev either until I know it really works)...I would 
expect udev to be in this same menu area but it is not. Kernel docs just 
call it hotplug as the replacement, which I know I have, because USB 
plugins generate a log message. My option for "Hotplug firmware loading 
support" (CONFIG_FW_LOADER) is set to module, but I have a feeling this 
is more to do with how it deals with hotplug device installs once it has 
detected the device, rather than the device detection.

On a side note, docs in 2.6.9 mention /proc/sys/kernel/hotplug, and 
indeed I have this file, the content properly points at /sbin/hotplug. 
With this file being generated by the kernel, it is yet more evidence 
that hotplug is supported. In any case I don't believe hotplug applies 
since the standard game port is not a hotplug device, and cannot 
generate hotplug events. Add to this that I have the files in /dev/, and 
they are static, never-changing, and much of this hotplug thing is to 
generate those files (not to load drivers...I suspect this would be a 
separate mechanism).

> So it used to be that you had a /dev node and "opening" it could clue 
> the kernel to load the driver.  Now there is no dev node and you need 
> something else to detect the hardware, load the module, and clue udev to 
> make a node for it.

I have the node, it's static, no udev or devfs. The cable and connecter 
are standard game port.

> I think that something is hotplug.  Are you using that?  When the kernel 
> notices new hardware it runs hotplug, which loads the driver and does 
> whatever other configuration is required to use the device.  That 
> includes making the udev node.

Have hotplug, but so far as I can tell hotplug is only related to 
hotplug type connections, e.g., USB, firewire, PCMCIA, such that older 
standard ports like serial and parallel ports, and game ports, would be 
unrelated.

> That's the way I understand it anyway.  So you might have to add some 
> stuff (udev, hotplug).
> 
> Otherwise, there may be some way your distro autoloads modules.  In 
> Debian there's a /etc/modules file that lists modules that get loaded 
> automatically by an init script (a distro approved bogus rc.local 
> command).  Each module listed gets modprobed when the script runs.

That's what I'm having a problem figuring out. The 2.6 kernel abandoned 
/etc/modules.conf, and added /etc/modprobe.conf. Hotplug takes care of 
pluggable devices on USB, firewire, and PCMCIA, but this is not one of 
those devices. On the other hand, hotplug detects device 
attachment/detachment, whereas I'm worried about a program doing the 
reverse: Attempting to use /dev/input/js0, to generate an event to load 
modules, rather than a connector based event.

Has anyone here at all ever succeeded on a 2.6 kernel with a sblive! 
game port to get it to auto load the right modules without a manual 
entry into rc.local? It seems like 2.6 has abandoned older devices.

D. Stimits, stimits AT comcast DOT net