How do I give the kernel a parameter.

stf92 · 01-26-2013, 02:09 PM

Hi: I use lilo as the boot loader. When control passes to the boot loader, I can type 'lin', the label of the OS to boot, supposedly followed by some paramenter. Suppose the lilo prompt is 'lilo ' (I do not remember well). Then

Code:

lilo lin abcd

will be accepted by lilo. I.e., it accepts anything. I've writen a valid parameter name, but with no effect at all. How do I pass the kernel a parameter at boot time?

syg00 · 01-26-2013, 02:34 PM

Generally parameters not recognised are ignored and passed on. This is true of grub, and presumably lilo (which I haven't used in years).
Likewise the kernel will ignore anything passed to it if it doesn't recognise it - parameters change as kernels develop; new parameters come in, sometimes (rarely) old ones get removed.

Quote:

I've writen a valid parameter name, but with no effect at all

Provide some evidence.

stf92 · 01-26-2013, 03:08 PM

Easy. I used sr0=ide-scsi. I discover, though, that the kernel must have SCSI emulation builtin. Does this make sense to you?

syg00 · 01-26-2013, 03:24 PM

Surely. The kernel is monolithic, but as options are compiled in they bring with them code to handle their own parameters.
If that option isn't there, the parameter isn't "valid" (as no code recognises it), and it gets ignored.

This makes sense - it is possible (common) to pass parameters to initscripts via the boot arguments; they just get ignored by everybody until the initscript processes them.