Why do you think this is a e2fsprogs bug? You didn't say what kind of usb drive this was, but if it was a USB thumb drive, the 120 second stall was probably because USB thumb drives was slow.
Also, mke2fs must have completed if the shell script had gotten to the
"cryptsetup close prn" command. As to why it thought the device was
busy, that's between cryptsetup and the kernel, and e2fsprogs has
nothing to do with this.
Can you reproduce this reliably?
- Ted
