I am having a problem running Ubuntu 12.04.1 under VMWare 9.0.1. I think that it has to be VMWare related because the same operations work fine as far back as RedHat 7.2 and Ubuntu 8.04.4.

Assume the existence of a file called 'image.bin' created by copying data from e.g. a CF card.

Steps are:
losetup -o 16384 /dev/loop0 image.bin
mount /dev/loop0 /mnt/tmp -t vfat

Under the working OS, it just mounts. In the VMWare configuration, it reports:
mount: block device /dev/loop0 is write-protected, mounting read-only

Of course, this makes it difficult to add the required data to the file! I have tried any number of things like mounting with -o remount,rw but nothing seems to make a difference. I am running as root in all cases just to make sure there are no permissions issues related to this, but the file permissions seem like they should be fine:

-rwxrwxrwx 1 root root 130023424 May 6 17:55 image.bin
brw-rw---- 1 root disk 7, 0 May 6 18:08 /dev/loop0

Any insights?

Greg

Ok this is a strange one, but by chance try creating a fresh loop device to mount with: