Comment 19 for bug 291752

Comments from Scott James Remnant, resident udev expert:

18:05 < Keybuk> device node can exist, but have no filesystem inside it, because other things need to do magic
18:05 < Keybuk> e.g. md and devmapper devices
18:06 < Keybuk> the device node shows up when you create the name
18:06 < Keybuk> before you load the table
18:07 < Keybuk> so you need to check
18:07 < Keybuk> 1. does the device node exist? [ -e ]
18:07 < Keybuk> 2. has udev finished with it? udevadm settle
18:07 < Keybuk> 3. has it got a filesystem inside it? vol_id

We actually probably *don't* need 3) as long as we have 2); but in any case this explains why the preceding update was wrong (though it surprises me that anyone is hitting this race in practice). I'll prepare an emergency update to revert this change, then we can re-evaluate how to fix this for everyone in SRU.