Andreas Enge <andr...@enge.fr> skribis: > On Thu, Mar 10, 2016 at 10:17:46AM +0100, Ludovic Courtès wrote: >> IIUC we don’t *have* to pass the UUID to ‘cryptomount’; we could also >> pass the device name, in GRUB format > > Yes, but my idea was that the uuid is something we can determine > at instantiation time. If the mapped device is /dev/sdd3, we can run > (system* "cryptsetup" "luksUUID" "/dev/sdd3") > and obtain the uuid.
Hmm yeah, but we don’t even do that for regular partitions. > I suppose we could also use the grub device (hd3,msdos3) in this case, > but I do not know what is the mapping between /dev nodes and these devices, > and if it is actually a function that could be computed from the file name > in /dev only or not. ‘grub-probe’ should know, I think. >> (mapped-device >> (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44")) ;LUKS UUID >> (target "root") >> (type luks-device-mapping)) >> we’d have to extend <mapped-device-kind> with a method to resolve UUIDs >> (in this case, to map a UUID to a /dev node.) > > We can also let the users do the work (and document this in the manual), > by having them supply all the informatin: > > (mapped-device > (source "/dev/sdd3") > (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44") ;LUKS UUID > (target "root") > (type luks-device-mapping) > (needed-for-boot? #t)) I think the goal of providing a UUID is to not have to worry about the actual device name (which could change). The ‘needed-for-boot?’ flag should be unnecessary because it can be inferred from corresponding file systems, as is already the case. >> Besides, I think we should only worry about the mapped device(s) that >> back / and /boot, rather than any mapped device, no? > > This could either be solved by determining which file systems have > needed-for-boot? #t and determine the corresponding mapped devices, > or by adding such a parameter for the mapped-device as in my suggestion > above. > > Or we do it all automatically for / and /boot and drop the parameter > needed-for-boot? everywhere. We keep it only in ‘file-system’, I think. Anyway, sounds like quite a bit of work here. :-) Ludo’.
