I am using the package drbd-0.7.13. When the drbd module loads, the devices specified in its config file automagically appear in /dev. These are usually /dev/drbd0, /dev/drbd1, etc. This was working linux-2.6.12-gentoo-r1. The version of udev I am using 065 and 068 does not seem to matter. It definitely stopped working in linux-2.6.12-gentoo-r10. I tried the vanilla sources and found it to be working fine in vanilla-sources-2.6.12.5.ebuild. There is no vanilla-sources-2.6.12.6.ebuild in the portage tree even though there is an official kernel patch for it. I made one and tried it. Still works. However, the vanilla for 2.6.13 does not work. That means something was changed in 2.6.13 to cause the problem and whatever it was got backported into linux-2.6.12-gentoo-r10. It's not entirely clear which patchset (patches-2.6.12-14?) you apply to this particular version, but it contains the bug. Reproducible: Always Steps to Reproduce: 1. 2. 3.
So gentoo-sources-2.6.12-r9 works fine (and continues to work fine when you boot into it at this point)? Patchset info is found at http://dev.gentoo.org/~dsd/genpatches/
It's really bizarre, but I can't reproduce it any longer. I tried r7 and it worked, then r9 and it worked. Finally r10 and now it's working. And even plain 2.6.13 and it's working!
