(stupid) how to specify the root-device via kernel parameters

[Christoph Anton Mitterer <calestyo@scientia.net>]

Hi,...

Ok this might sound really stupid, but I've seen several ways of doing
this and want to get this cleaned up.

Nevertheless....

kernel-parameters.txt has the following options where you can specify
the root-fs and related flags:
root=           [KNL] Root filesystem
nfsroot=        [NFS] nfs root filesystem for disk-less boxes.

Plus further options like: ro, rootdelay=, rootflags=, rootfstype=,
rootwait, etc.


My question:
These are intended (especially root/nfsroot) to really name the device,
on which the filesystem directly lays, right?
E.g. if the ext4-root-fs is on /dev/sda1,... => root=/dev/sda1

I've seen several initramfs scripts (which I'd like to fix),... where
people abuse this or misuse this in setups where a root-fs is used on
multi-stacked block layers (e.g. something like disk->lvm->dm-crypt->fs)


Cheers,
Chris.