if baselayout /sbin/rc does the udev case a new /dev is created and populated by udev. udev however only created /dev/mapper/control and ignores other dm* devices. In case a initrd was used to setup some device mapping (e.g. a crypt layer for /), then a device for that mapping should be created. if you could check in /sbin/rc (in the udev branch) for dmsetup and - if it exists - call it with "mknodes", then it will create such pre-configured mappings. Reproducible: Always Steps to Reproduce: 1. use some initrd to create a mapping before the real boot 2. make it boot gentoo, with new / and using kernel 2.6 with udev 3. look at the new /dev/mapper/ directory. Actual Results: you will see only "control", but not the mapping you created in step 1. if you look at /initrd/dev (if you kept that), you will still see that it was created ok in the initrd. Expected Results: check for dmsetup and call "dmsetup mknodes" which will read the kernel information on configured mappings and create appropriate devices if missing.
"dmsetup mknodes" is one way of doing things, although in a way your not letting udev set up the device nodes which means if you want to create symlinks as part of the udev rule (e.g. for evms) you won't be able to via udev another way is to use a later version of dmsetup later than 1.00.20 (1.00.21 is the nearest but is currently masked) dmsetup -j <major> -m <minor> will identify a device-mapper table entry name which you can then fit in as part of the udev rules in theory you'd be able to do stuff like create symlinks for lvm or evms, or even specific links for particular Hard disks (usefull for Raid) http://forums.gentoo.org/viewtopic-t-263996-highlight-.html
any solution is fine with me, if it provides the real system with a device node for a dm mapping, that was already created in an initrd/initramfs. I thought /sbin/rc is the proper place, but other options are fine with me, too. I'm sorry to tell you that I moved to a different OS in the meantime, so I can't test any potential solution any more.
this is in baselayout-1.11.13
