[lug] logging missing 2.6 kernel modules
stimits at comcast.net
Mon Jun 13 11:40:25 MDT 2005
Zan Lynx wrote:
> On Sun, 2005-06-12 at 23:25 -0600, D. Stimits wrote:
>>Lee Woodworth wrote:
>>>In reviewing the hotplug and udev stuff, I was reminded of
>>>some things I have seen on the web that apply:
>>> Kernel version 2.6 will not automaticlly load device drivers
>>> when a related device node is accessed. The major reason
>>> being that there is interest in having device major/minor
>>> become dynamially allocated. For example the device mapper
>>> (dm_mod) already uses a dynamic minor number for
>>>You may be interested in this excerpt from the udev FAQ:
>>> Q: But udev will not automatically load a driver if a /dev node is opened
>>> when it is not present like devfs will do.
>>> A: If you really require this functionality, then use devfs. It is still
>>> present in the kernel.
>>As far as I know I'm not using udev. For the old devfs it's easy to
>>check (not using it), I'm coming up blank trying to figure what kernel
>>config is for udev.
> There is no kernel configuration for udev. The "u" in udev is for
> user-space. The only bit that is done in the kernel is hotplug
> notification. udev picks up static devices through boot scripts, called
> hotplug or coldplug, depending on the distro. The boot scripts scan for
> hardware and simulate hotplug calls for the hardware.
> For Gentoo, they have a coldplug script but recommend loading the
> modules statically if you know what you've got plugged in, since it is
Sounds like I'm missing the coldplug scripts, as my hotplug obviously
isn't doing it. Or perhaps there's a config somewhere for hotplug on
fedora that does not depend on hotplug events. The part where it scans
for non-hotplug hardware during boot is either missing, or part of a
config I can't find for the joystick. I'd think by now the sblive would
be detected in distros (meaning the joystick port, not just sound).
>>> Q: But wait, I really want udev to automatically load drivers when they
>>> are not present but the device node is opened. It's the only reason I
>>> like using devfs. Please make udev do this.
>>> A: No. udev is for managing /dev, not loading kernel drivers.
>>I'm actually hoping for some *other* mechanism to do this, not udev.
> If you set the option in the kernel configuration, it will still call
> out to modprobe to load things like SCSI or network drivers. If that
> isn't working, it could be that modprobe is disabled by your distro
> writing an empty line into /proc/sys/kernel/modprobe. Make sure that's
> set to /sbin/modprobe.
Nope, I checked this a while back, it is there and runs fine. I even
reported it in an earlier email. Modprobe might have some further
config, but as it is it runs and fails (why did they have to remove
/etc/modules.conf? Such a tragedy of complications).
D. Stimits, stimits AT comcast DOT net
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