Re: module: sysfs - add 'uevent' file to allow coldplug

[Rusty Russell <rusty@rustcorp.com.au>]

On Mon, 20 Jun 2011 13:20:00 +0200, Kay Sievers <kay.sievers@vrfy.org> wrote:
> On Mon, Jun 20, 2011 at 01:23, Rusty Russell <rusty@rustcorp.com.au> wrote:
> > On Sun, 19 Jun 2011 00:00:29 +0200, Kay Sievers <kay.sievers@vrfy.org> wrote:
> >> From: Kay Sievers <kay.sievers@vrfy.org>
> >> Subject: module: sysfs - add 'uevent' file to allow built-in coldplug
> >>
> >> Userspace wants to manage module parameters with udev rules.
> >> This currently only works for loaded modules, but not for
> >> built-in ones.
> >
> > I'm confused.  What does "manage" mean here?
> 
> Hook system management into module-load events, which might include
> changing module parameters in /sys/module/*/parameters/*, or at
> bootup/coldplug run it for built-in modules.
> 
> We do the same to set properties for buses, drivers or devices when they appear.

Sorry, that's another vague answer :(

udev already knows about module load, and the parameters are created at
that point; they are not *changed*.

What, *exactly* will this enable?  Don't use the word "hook" or
"management": both vague terms which assume I know what you're talking
about.  I don't.

Show me exactly what udev will now be able to do that it can't do now,
and how it will be used.  Preferably with examples.  Assume (correctly)
that I have only a vague idea what udev does.

Thanks,
Rusty.