qemu-nbd -d fails silently #95
Description
qemu-nbd -d fails silently and leaves a nbd? show in /proc/partitions
I assume that this is because it was run on a device where partitions were still mounted.
Could you give the code some attention and get it to check /proc/partitions for success and warn the user on failure.
You can get into a very wierd state: when you find the device still in /proc/partitions you naturally run partprobe and may be surprised by the results:
Error: Partition(s) 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, \
17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64 on /dev/nbd3 have been written, but we have been unable to inform the kernel of the change, probably because it/they are in use. As a result, the old partition(s) will remain in use. You should reboot now before making further changes.
Surprise will give way to WTF as partprobe then reports the same error on all of your partitons.
WTF may give way to WhoKnows when you find you can clear the problem (perhaps) withour rebooting,