Comment 58 for bug 802626

So, I spent some time looking at herton's fix, and I think it's correct. While using --noudevsync looks tempting, is does trigger some new races since now both udev and lvm are trying to do things like renaming device nodes. Watershed isn't a problem -- DM_COOKIE is passed separately via dmsetup rules (grep for DM_COOKIE in /lib/udev/rules.d). So, we need to not drop the DM_COOKIE events, which is what this patch does. I'll get this tested shortly and then we can get this uploaded to precise and backported to oneiric.