I have been hit by this bug. My analysis of the situation is the following.
mdadm-3.1.2 introduced a change that stores a ``mapfile'' in /lib/init/rw. The problem is that this directory does not exist in the standard initramfs. Previous versions of mdadm were storing the file in /dev/.mdadm (which exists), and mdadm-3.1.3 also stores the file /dev/.mdadm. What happens seems to be the following. When assembling an array mdadm invokes udev to create symlinks to the new file in /dev; in turn, udev invokes mdadm to obtain information about the array. For reasons that I don't understand, the lack of the mapfile causes mdadm to scan for the array again, causing another notification to udev. The loop repeats forever. Presumably the mapfile is a cache of known arrays, and normally mdadm breaks the loop after noticing that the array is already present in the mapfile. This safety net disappears if the mapfile cannot be written. It appears that all problems go away by recompiling mdadm after changing a definition in the Makefile from ALT_RUN = /lib/init/rw to ALT_RUN = /dev/.mdadm I recommend the following: 1) this but ought to be reclassified a release-critical. It makes many machines unbootable and it must not be allowed to reach squeeze. 2) A workaround to debug is to change ALT_RUN as described above. However, I would strongly recommend the Debian maintainer to switch to mdadm 3.1.3 for squeeze, which seems to fix a few other scary bugs. Regards, Matteo Frigo -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
