tgtd target will not start unless it's configured with "allow-in-use yes"

I am also positive no other tgtd process where running at the same time.

Will take a look at this asap, probably during the sprint this next week.

When you get that error what does the following show:

"# Run 'lsof /dev/sda' to see the details."

I see you ran it in your comment above, but was it immediately after the error happened or some time later?

Hmm looking at the code I think its buggy. I'm not sure what it is actually trying to do but it doesn't seem to be doing it right in any case. It appears to be 8 bit shifting left, and then checking for 0. If the device is in use lsof returns 0 if it is not then it returns 1, at least as best as I can tell, in which case doing the bit shift causes the problem. I am not sure why it was added, but it probably was needed for something.

        # Check if userspace uses this device
        my $lsof_check = check_exe("lsof");
        if ($lsof_check ne 1) {
                system("lsof $backing_store &>/dev/null");
                my $exit_value = $? >> 8;
                if ($exit_value eq 0) {
                        execute("# Device $backing_store is used (already tgtd target?).");
                        execute("# Run 'lsof $backing_store' to see the details.");
                        return 0;
                }
        }
        return 1;
}

It appears to be a bug caused by using this:

                system("lsof $backing_store &>/dev/null");

instead of:

                system("lsof $backing_store >/dev/null 2>&1");

I was confused earlier about the direction of bitshift since the wrong calling convention was causing it to always return 0.

Forgot the # in the closes line in the upload. It was fixed in tgt 1:1.0.4-1ubuntu3