kern/41127: Creating a new filesystem on usbstick fails

[kaph%zhaw.ch@localhost]

>Number:         41127
>Category:       kern
>Synopsis:       Creating a new filesystem on usbstick fails
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Apr 03 13:10:00 +0000 2009
>Originator:     Christoph Kaegi
>Release:        5.0_RC2 20090315
>Organization:
>Environment:
NetBSD clt-mob-v-0289 5.0_RC2 NetBSD 5.0_RC2 (GENERIC) #0: Sun Mar 15 21:32:21 
UTC 2009  
builds%b6.netbsd.org@localhost:/home/builds/ab/netbsd-5/i386/200903150000Z-obj/home/builds/ab/netbsd-5/src/sys/arch/i386/compile/GENERIC
 i386
>Description:

Sticking a freshly cleaned (dd if=/dev/zero of=/dev/sd0d bs=512 count=1)
usb stick into the machine, labeling it (disklabel -re sd0) and trying to 
create an ufs filesystem on it (newfs /dev/sd0a) fails with:

newfs: /dev/sd0a: open for write: Device busy

Nothing obvious uses the usb stick. Rebooting changes nothing. Tested on Dell 
Latitude E6400 and a Dell Desktop GX280.

Accessing an usb stick which already contains an ffs filesystem works ok.
>How-To-Repeat:

- put an usb stick into your 5.0_RC2 machine
- dd if=/dev/zero of=/dev/sd?d bs=512 count=1
- disklabel -re sd?
- newfs /dev/sd??
>Fix: