ogra@anubis:~/datengrab/rpi$ sudo ubuntu-device-flash core --channel=stable --oem pi2_0.13_all.snap --developer-mode --install webdm --device-part=device-pi2-0.13.tar.xz -o pi2.img 15.04
Determining oem configuration
Fetching information from server...
Downloading and setting up...
Installing pi2_0.13_all.snap
Installing webdm
Starting download of webdm
6.16 MB / 6.16 MB [==============================================================================================================================================================================================================================================================================] 100.00 % 328.68 KB/s 
Done
Enabling developer mode...
panic: unable to unmount dir for image: umount: /tmp/diskimage643565256/system: Gerät ist in Benutzung.
        (In einigen Fällen finden Sie verwertbare Informationen
         über die Prozesse, die dieses Gerät nutzen, mit lsof(8)
         oder fuser(1))


goroutine 1 [running, locked to thread]:
launchpad.net/goget-ubuntu-touch/diskimage.(*CoreUBootImage).Unmount(0xc2081286e0, 0x0, 0x0)
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/goget-ubuntu-touch/diskimage/core_uboot.go:115 +0x67d
main.func·006()
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/goget-ubuntu-touch/ubuntu-device-flash/core.go:341 +0x120
main.(*CoreCmd).setup(0xcf0920, 0x7f585e35bca0, 0xc2081286e0, 0xc2080b12c0, 0x3, 0x0, 0x0)
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/goget-ubuntu-touch/ubuntu-device-flash/core.go:405 +0x1753
main.func·004(0x0, 0x0)
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/goget-ubuntu-touch/ubuntu-device-flash/core.go:280 +0x171
main.(*CoreCmd).Execute(0xcf0920, 0xc20800a0c0, 0x1, 0xc, 0x0, 0x0)
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/goget-ubuntu-touch/ubuntu-device-flash/core.go:285 +0x20d9
github.com/jessevdk/go-flags.(*Parser).ParseArgs(0xc2080566c0, 0xc20800a000, 0xc, 0xc, 0x0, 0x0, 0x0, 0x0, 0x0)
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/github.com/jessevdk/go-flags/parser.go:241 +0x8b8
main.main()
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/goget-ubuntu-touch/ubuntu-device-flash/main.go:62 +0x3ac

goroutine 5 [syscall]:
os/signal.loop()
	/usr/lib/go/src/os/signal/signal_unix.go:21 +0x1f
created by os/signal.init·1
	/usr/lib/go/src/os/signal/signal_unix.go:27 +0x35

goroutine 6 [chan receive]:
launchpad.net/snappy/partition.func·005()
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/snappy/partition/partition.go:270 +0x52
created by launchpad.net/snappy/partition.setupSignalHandler
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/snappy/partition/partition.go:275 +0x21e

goroutine 17 [syscall, locked to thread]:
runtime.goexit()
	/usr/lib/go/src/runtime/asm_amd64.s:2232 +0x1

goroutine 40 [chan receive]:
main.func·003()
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/goget-ubuntu-touch/ubuntu-device-flash/core.go:261 +0x1e8
created by main.(*CoreCmd).Execute
	/build/buildd/goget-ubuntu-touch-0.23/obj-x86_64-linux-gnu/src/launchpad.net/goget-ubuntu-touch/ubuntu-device-flash/core.go:264 +0x2015
ogra@anubis:~/datengrab/rpi$