SOLVED - Re: KERNEL - knowing what programs use/need modules

Damien Fleuriot ml at
Mon Jan 2 11:58:39 UTC 2012

On 1/1/12 9:10 AM, Matt Mullins wrote:
> 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
> up.
>> 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?

They use mfi, like a few others which do not have CAM loaded.

The best part is, after rebooting these firewalls on their new
8.2-RELEASE-p5 kernel, they haven't loaded neither of UMS, UMASS, or
CAM, although I've clearly built them:

MODULES_OVERRIDE=cam geom/geom_label if_lagg linprocfs linsysfs linux
mfi/mfi_linux usb/umass usb/ums

I doubt another admin would have loaded them manually, they don't touch
the "freebsd stuff" very often ;)

Ah well, I guess I'll just leave it at that.

For anyone reading this thread, Matt's suggestion of using lsof to find
what files/binaries could be using the devices seems to be the best one.

Ty for the input Matt.

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