block-attach/detach device oddness

[Jeff Rizzo <riz%tastylime.net@localhost>]

I was adding a block device to a NetBSD 6.0 domU (on a 6.0_BETA dom0), 
and I made a mistake by giving the raw dev instead of the block:

xenserver1:riz  ~> sudo xm block-attach blork 
phy:/dev/mapper/rmirror-currentsrc sdg w

...which showed up in the domU thus:

xbd2 at xenbus0 id 2144: Xen Virtual Block Device Interface
xbd2: using event channel 15


(Note no size info).

So, once I figured out what I'd done, I detached it:

xenserver1:riz  ~> sudo xm block-detach blork sdg

domu:
xbd2: detached


...I then tried attaching the block device:

xenserver1:riz  ~> sudo xm block-attach blork 
phy:/dev/mapper/mirror-currentsrc sdg w
Error: Device sdg (2144, vbd) is already connected.
Usage: xm block-attach <Domain> <BackDev> <FrontDev> <Mode> [BackDomain]

Create a new virtual block device.


It attached fine as sdh, though:

xenserver1:riz  ~> sudo xm block-attach blork 
phy:/dev/mapper/mirror-currentsrc  sdh w

domU:
xbd2 at xenbus0 id 2160: Xen Virtual Block Device Interface
xbd2: using event channel 16
xbd2: 5120 MB, 512 bytes/sect x 10485760 sectors


It's not really a problem, but shouldn't the xenbus id be reusable?

+j