No uevent when loop devices get removed

Binary package hint: udisks

I'm seeing some partitions persist even after I've removed them.

In this case today I used a loopback filesystem (setup with a mount -o loop) from a file that happened to be on a mounted
thumb drive (it was the -rw backing store of a bootable usb); but even though I've unmounted it and losetup -a doesn't show it,
udisks --enumerate still shows:

/org/freedesktop/UDisks/devices/loop0

and my disk mounter applet still shows an icon that I think corresponds to it.

The following is a section of a udisks --dump; note I can see that /dev/disk/by-uuid still has the entry linking to ../../loop0.

I also saw a couple of days ago a situation where the main partition of a thumb drive was still shown after removing it; but
I didn't take any debug at that time.

========================================================================
Showing information for /org/freedesktop/UDisks/devices/loop0
  native-path: /sys/devices/virtual/block/loop0
  device: 7:0
  device-file: /dev/loop0
    presentation: /dev/loop0
    by-id: /dev/disk/by-uuid/7080535a-eda4-49e0-bb52-ac425faeb859
  detected at: Fri 02 Apr 2010 22:37:29 BST
  system internal: 1
  removable: 0
  has media: 1 (detected at Fri 02 Apr 2010 22:37:29 BST)
    detects change: 0
    detection by polling: 0
    detection inhibitable: 0
    detection inhibited: 0
  is read only: 0
  is mounted: 0
  mount paths:
  mounted by uid: 0
  presentation hide: 0
  presentation nopolicy: 1
  presentation name:
  presentation icon:
  size: 3047161856
  block size: 512
  job underway: no
  usage: filesystem
  type: ext3
  version: 1.0
  uuid: 7080535a-eda4-49e0-bb52-ac425faeb859
  label:
  loop:
    filename: /media/3C74-BC4B/casper-rw
  drive:
    vendor: Linux
    model: Loop: casper-rw
    revision:
    serial:
    WWN:
    detachable: 0
    can spindown: 0
    rotational media: Yes, unknown rate
    write-cache: unknown
    ejectable: 0
    adapter: Unknown
    ports:
    similar devices:
    media:
      compat:
    interface: (unknown)
    if speed: (unknown)
    ATA SMART: not available

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: udisks 1.0.0+git20100319-0git1
ProcVersionSignature: Ubuntu 2.6.32-19.28-generic 2.6.32.10+drm33.1
Uname: Linux 2.6.32-19-generic x86_64
Architecture: amd64
CheckboxSubmission: f2d10bd9f943a85b486a282e7840a570
CheckboxSystem: 0531969bcfd4f03af7405c98dc94a948
Date: Sat Apr 3 01:07:30 2010
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release amd64 (20091027)
MachineType: To Be Filled By O.E.M. To Be Filled By O.E.M.
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.32-19-generic root=UUID=d8314979-8ace-401c-88df-728ad6b89cb5 ro ignore_loglevel netconsole=4444@192.168.66.33/eth0,514@192.168.66.25/00:a0:d1:63:68:a6 quiet splash
ProcEnviron:
 PATH=(custom, user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: udisks
dmi.bios.date: 09/10/2009
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: P1.50
dmi.board.name: P55M Pro
dmi.board.vendor: ASRock
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: To Be Filled By O.E.M.
dmi.chassis.version: To Be Filled By O.E.M.
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrP1.50:bd09/10/2009:svnToBeFilledByO.E.M.:pnToBeFilledByO.E.M.:pvrToBeFilledByO.E.M.:rvnASRock:rnP55MPro:rvr:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.:
dmi.product.name: To Be Filled By O.E.M.
dmi.product.version: To Be Filled By O.E.M.
dmi.sys.vendor: To Be Filled By O.E.M.