We might have some corruption issues for dm-crypt. I recently switched to an LVM setup that is backed by a single physical volume accessed via dm-crypt. I have seen strange corruptions with cryptsetup, incompletely written headers that were reproducible 4/5 of the time. I blamed the fact that I had orphaned mappings to the corrupting device (left overs of temporary-cryptsetup-mapping). The upcoming version of cryptsetup will require exclusive access to the underlying device and also trap ctrl-c's so that these mappings are removed. After hacking these sanity checks into cryptsetup, this thing went away. But it doesn't look like that this was the thing to blame. Yesterday I renamed the LVM volume (vgrename), and after that the LVM header was corrupted. LVM is in the same position as cryptsetup (although it does not know). cryptsetup sets up a temporary mapping and opens this raw block dev to write headers. LVM gets a block device and also writes header by opening the raw block device. So these positions are identical when you hand an encrypted volume to LVM as physical volume. I neither have a reproducible test case, only the observation that things didn't happen that way in 2.6.20 (2.6.21 was affected too, sorry it's too long ago I can't remember the setup details precisely). I have the strong suspicion that your LUKS disk might DIE due when it trying to touch the header and only a corrupted header version is written. Unfortunately, I don't have much time to look at this at the moment. I suspect this is some kind of race (yeah fun to debug!). This message should only serve as warning that you might not want to go for any kernels more recent than 2.6.20 with LUKS. Sorry for the ultra-vague information. Christophe, Alasdair: has anything crossed your way that might explain this/looks familiar? -- Fruhwirth Clemens - http://clemens.endorphin.org --------------------------------------------------------------------- dm-crypt mailing list - http://www.saout.de/misc/dm-crypt/ To unsubscribe, e-mail: dm-crypt-unsubscribe@xxxxxxxx For additional commands, e-mail: dm-crypt-help@xxxxxxxx
