There is something in the "config" semantics which
looks like an inconsistency to me:

Attributes are used in the "files.*" files to set up the rules
how the device tree is built.
Imho, these attributes should not be used in the kernel
configuration files.
The only place where I found a use of this (in the i386 port)
is the "pckbd" attribute. "files.i386" contains:
	device	pc: tty, pckbd
and
	device	vt: tty, pckbd
GENERIC contains:
	pms0	at pckbd? irq 12

Do we really want this? "pckbd" doesn't appear in the
config file otherwise, so this is at least confusing.
2 lines:
	pms0	at pc? irq 12
and
	pms0	at vt? irq 12
would express the same in a clean way.

Look at the SCSI bus attachment:
	scsibus* at aha?
	scsibus* at ahb?
	scsibus* at ahc?
	[...]
Here it is done right. (One could write "scsibus* at scsi?", using
the internal "scsi" attribute.)

Shouldn't the attachment to pure attributes be disallowed in
"config"?

best regards
Matthias