Re: [patch 2.6.21-rc5-git 1/2] fix hotplug for legacy platform drivers

[Cornelia Huck <cornelia.huck@de.ibm.com>]

On Mon, 2 Apr 2007 09:59:28 -0700,
David Brownell <david-b@pacbell.net> wrote:

> But long term, I wonder.  Isn't "no kevents issued" an extremely
> blunt tool, which could cause lots of damage?  It might be better
> to have selective filters, one per event family:  core (add/remove),
> online/offline, mount/unmount, etc.

It all depends on your use case :) But yes, we could introduce some
flags that selectively filter out some groups of uevents.

> But in general it's worth thinking about.  The comments on that
> "suppress all kevents" patch didn't include any motivation at all.
> Why do you want to prevent all kevents, rather than just a subset?

Currently, some drivers (like firmware_class) return an error code in
their uevent function in order to suppress uevents until they did some
setup. It seemed cleaner to use uevent_suppress and filter until they
were ready. For s390, we have the problem that we get a storm of
uevents for devices which aren't useable after all; we can use
uevent_suppress to make sure that userspace doesn't know anything about
those devices until we're really sure we want to keep them.