KERNEL - knowing what programs use/need modules

Matt Mullins mokomull at
Sun Jan 1 08:10:48 UTC 2012

On Tue, Dec 27, 2011 at 8:34 AM, Damien Fleuriot <ml at> wrote:
> Now, I'm wondering why in the world a server would need umass, ums and cam ?
> My understanding is that ums is the USB mouse, which we're never going
> to need.
> Umass would be USB mass storage, which again we're never going to need.

You appear to be correct with these two.  My gut tells me these types
of things would be loaded when the corresponding devices are plugged
into the system, but if that's wrong, surely someone here will speak

> Regarding CAM I have absolutely no idea why the module is loaded either.

That's the SCSI/ATA subsystem; if this is the only of your firewalls
to have this module, perhaps it has different disk adapter hardware
than the others or another sysadmin decided to load it manually?

> Are there any ways of finding what programs, if any, require or use said
> modules ?

I'd probably start with judicious use of sysutils/lsof to find any
programs that have the relevant device nodes open.  "grep -Rl" through
your binary directories might also find something, but I'd expect a
very high false-positive rate with that.

Hope any of this helps,
Matt Mullins

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