usb/121168: Kernel panic when try to unmount removed usbdrive

[M. Warner Losh]

In message: <20080228100132.GH83599 at server.vk2pj.dyndns.org>
            Peter Jeremy <peterjeremy at optushome.com.au> writes:
: On Thu, Feb 28, 2008 at 12:47:41PM +0300, Yuri Pankov wrote:
: >Though, problem was "fixed" (I hope) in this commit:
: >http://lists.freebsd.org/pipermail/cvs-src/2007-December/085533.html
: 
: That patch begins "partial solution" though it avoids at least one
: panic path.  It's not clear whether other panic paths still remain.
: (Though any unwritten data is still toast).

Big band aides, but they help a lot.  They at least let you shutdown cleanly.