Am 27.12.2011 19:08, schrieb Dieter Plaetinck:

/dev/dm-0 /dev/dm-1 /dev/dm-2 /dev/loop0 /dev/loop1 /dev/loop100 /dev/loop101 /dev/loop102 /dev/loop103 /dev/loop104 /dev/loop105 /dev/loop106 /dev/loop107 /dev/loop108 /dev/loop109 /dev/loop110 /dev/loop2 /dev/loop3 /dev/loop4 /dev/loop5 /dev/loop6 /dev/loop7

are these all created by archiso? what exactly are they for?

I'll try to figure this out: loop0-loop7 are loop devices allocated by default - this happens because old userspace can't use the new loop-control device and needs preallocated devices. The rest (on the image I just booted): /dev/loop100 is a block device for root-image.fs.sfs (squashfs, read-only), which is mounted. /dev/loop101 is a block device for the file root-image.fs, which is a (sparse) ext4 file system image (inside squashfs, read-only). /dev/loop102 is a block device for the sparse file /run/cowspace/root-image.cow (which is on tmpfs, read-write). The last two loop devices are put together into a device mapper snapshot device (dm-0), which is then mounted as /. The exact same thing happens for lib-modules.fs.sfs and usr-share.fs.sfs, creating loop103-loop108, dm-1 and dm-2. You booted a core image, so you have loop109 and loop110 as well, which are probably for the pkgs-$ARCH and pkgs-any squashfs. This block-based unioning/snapshotting is certainly not optimal, but it is stable and supported by unpatched kernels. We don't have a file-based solution that fulfills these criteria.

does anyone know what is the best way to ignore them? * some property in /sys/block/<dev>/ ? * how about just maintaining a list of exactly all these filenames .. or: * how about having archiso maintain a file called /var/aif-blockdevices or something? then aif can read that file and ignore blockdevices based on what it finds there. (just don't call it archiso-blockdevices or something, because AIF is supposed to be able to run in several environments)

Maybe not /var, but /run. Another way: use udevadm control --property=AIF_IGNORE=1 [...] This should work :)