Re: Q: acpi-cpufreq module auto-loading after processor driver change

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Thu, May 30, 2013 at 11:38:37PM +0200, Rafael J. Wysocki wrote:
> Hi Greg,
> 
> I've noticed during recent testing that with this commit applied:
> 
> http://git.kernel.org/cgit/linux/kernel/git/rafael/linux-pm.git/commit/?h=acpi-hotplug&id=ac212b6980d8d5eda705864fc5a8ecddc6d6eacc
> 
> on my openSUSE (and Tubmbleweed) installations I need to modify
> /etc/sysconfig/kernel to make mkinitrd put the acpi-cpufreq module into the
> initramfs or otherwise it won't be loaded automatically.
> 
> I think I understand why it needs to be present in the initramfs along the
> processor module for the automatic loading to work (acpi_processor_load_module()
> seems to need that), but before the above commit it wasn't necessary to make
> any changes to /etc/sysconfig/kernel and acpi-cpufreq was loaded automatically
> anyway.
> 
> Unfortunately, my experience with udev and related things is kind of limited
> and I have no idea what exactly makes the difference.  Can you please have a
> look and help me understand that?

Don't you need a MODULE_DEVICE_TABLE() macro in that module somewhere so
that udev and the like know to load it when it sees the hardware?

thanks,

greg k-h