Comment 9 for bug 974374

Just got hit by the same thing and completely unrelated to comment #4. We had this with fully formed paths (with slashes) and an NFS server that went away suddenly. Trying unmount with -f , -l and those two flags in combination did not solve the issue. When I tried the suggestion in #7 I found it only has the effect of removing the line describeing the mount in /etc/mtab but not in /proc/mounts or actually doing an umount. This is why, I think, the poster gets the hang in his next comment (#8) as the mount is not actually unmounted, just no longer tracked in /etc/mtab.