bin/43315: dkctl causes illegal request with umass

[scotte%warped.com@localhost]

>Number:         43315
>Category:       bin
>Synopsis:       dkctl causes illegal request with umass
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun May 16 16:40:00 +0000 2010
>Originator:     Scott Ellis
>Release:        amd64-current (5.99.29)
>Organization:
None
>Environment:
NetBSD intrepid 5.99.29 NetBSD 5.99.29 (INTREPID.P5W) #0: Sat May 15 08:31:10 
PDT 2010  
scotte@intrepid:/nbu/source/netbsd/src/obj.amd64/nbu/source/netbsd/src/sys/arch/amd64/compile/INTREPID.P5W
 amd64

>Description:
Mounting a USB disk, and running 'dkctl' on it:
intrepid# dkctl /dev/sd0d
strategy:
/dev/sd0d: priocscan

cache:
/dev/sd0d: read cache enabled
/dev/sd0d: read cache enable is not changeable
/dev/sd0d: write cache enable is not changeable
/dev/sd0d: cache parameters are not savable

wedges:
/dev/sd0d: no wedges configured

causes the following to be output in the kernel message buffer:
sd0(umass0:0:0:0): illegal request, data = 00 00 00 00 24 00 00 00 00 00


Actual umass device is:
umass0 at uhub4 port 2 configuration 1 interface 0
umass0: JMicron JM20336 SATA, USB Combo, rev 2.00/1.00, addr 4
scsibus0 at umass0: 2 targets, 1 lun per target
sd0 at scsibus0 target 0 lun 0: <WDC WD50, WD-WMANU113, 07.0> disk fixed
sd0: 465 GB, 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 976773168 sectors

>How-To-Repeat:
Run dkctl on a umass device, and monitor the kernel messages.
>Fix: