I found the problem. Its in /etc/init.d/mountall.sh This script calls the mount-functions.sh script in /lib/init
One of the things it does is attempt to mount /run as a tmpfs and just after that the udev messages I already showed started happening
The key to this was in the boot log output where I have verbose set to "YES" and the line it output was
Thu Jun 21 18:12:43 2012: [....] Files under mount point '/run' will be hidden.
I tried commenting out the actual mount of /run but it meant that even in recovery mode I had no keyboard, and hotpluging it in and out didn't restore it. I had to use a rescue disk to recover the system. However when I did comment it out, these messages from udevd stopped.
-- Alan Chandler http://www.chandlerfamily.org.uk -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org