Re: Hardware Inventory [was: Re: ISA slot detection on PCI systems?]

[David Brownell <david-b@pacbell.net>]

> > /sbin/hotplug is called from the kernel only, right?
>
> Right.  But there's no reason it can't be called from any other place.
> It's just a userspace program with a well documented interface :)

Actually, it's already called from other places ... :)
/sbin/hotplug is called from the init.d/hotplug startup script.

There's a period during initial system boot when not all filesystems
or system services are available.  When the kernel calls out to
/sbin/hotplug in such a situation, hotplugging can't yet do it's job.

It's too early, the system isn't "hot" yet ... which is why I call this
problem the "coldplug" issue.   Even simple device setup
operations like modprobing may not be possible, much less
more complex ones like alerting/starting daemons.  So the
init.d/hotplug script, invoked later, fakes hotplug events to
make sure the same setup gets done, without requiring users
to unplug/replug devices.

- Dave