"... is missing a Linux kernel header" prints disk path instead of kernel path

[awwright]

I'm having trouble getting mlb2install to do anything and I'm getting the error:

mlb2install: <target> is missing a Linux kernel header

Shouldn't it be scanning for the linux kernel header? It looks like it is, but if it errors, it's printing <target> instead of <kernel>:

mlb2/mlbinstall.c

Line 77 in e63e4c5

errx(1, "%s is missing a Linux kernel header", target);

The original seems to print the correct argument:

https://github.com/wikkyk/mlb/blob/471ca9b3048ecb8e820333c737424a2c361d0569/mlbinstall.c#L61

[philhofer]

There are several incompatibilities between this tool and the original. One of them is that this one expects the kernel to already be present on the disk (at the user-specified lba). You'll need to dd it into the right place. I mostly wrote this tool to be compatible with another tool and a packaging framework for producing bit-reproducible images.

[awwright]

Right, and it appears as if it's scanning <kernel> for the header, but when it can't find it, reports <target> as the name of the file missing said header.

[philhofer]

The header is part of the kernel image, and we require that the the kernel image already be present on the drive. The code is complaining that it couldn't find a kernel boot header at the supplied lba. There is no argument to the program.

[awwright]

The header is part of the kernel image, and we require that the the kernel image already be present on the drive.

The kernel is on the same disk as the MBR I'm trying to write to. The problem is the error message gives me the impression it's looking for the kernel magic number at /dev/sda and not /boot/vmlinuz.

Can you clarify what you mean by "there is no argument to the program"? When I say arguments, I'm referring to the 3-4 command line arguments (the target to install the new MBR to; the kernel path; the kernel command line arguments; and the "-vbr" option).

[philhofer]

The kernel is on the same disk as the MBR I'm trying to write to. The problem is the error message gives me the impression it's looking for the kernel magic number at /dev/sda and not /boot/vmlinuz.

It is looking for the kernel magic number on /dev/sda (to sanity-check that the offset you provided on the command line actually is the start of a kernel image).

You need to reserve some space for the kernel before the first disk partition (i.e. "unformatted" space) and dd the kernel into that location.

Can you clarify what you mean by "there is no argument to the program"?

Apologies. I meant to write "no kernel argument to the program."