Re: boot loader that can read from partition?

On 19 Oct 2006 16:12:08 +0300 Lajos Parkatti <lparkatt@xxxxxxxxxxx> wrote:
| phil-news-nospam@xxxxxxxx writes:
|
|> rather start with something simpler than Grub.
|>
|> I don't like the idea of having to put filesystem knowledge in a bootloader.
|> That locks me into filesystem types it knows. And I don't like LILO's
|> method of keeping index blocks in the filesystem space (and its dependency
|> on filesystem data blocks not moving).
|
| It is /sbin/lilo that needs to have the index file in a filesystem,
| not LILO. You could copy most (all) of the LILO code and simply
| replace the references to sectors belonging to a file system with
| references to sectors somewhere else.
|
| So use the code, but don't run /sbin/lilo.

LILO still reads the list of sectors. It would still need to be changed
to iterate through a range of sectors.


|> I suppose having a boot loader that only knows PC/DOS style partitions is
|> a lock in, too. But it looks like things are simple enough that a different
|> instance could be made with knowledge of other partition types like BSD.
|
| Why do you need a partition? To get the starting point from the
| partition table. But you could save that pointer in the bootloader
| itself. And you need "dd of=/dev/hda seek= ..." instead of plain
| "dd of=/dev/hdaX ...".

To _write_ the kernel, of=/dev/hdaX will work.

The boot loader would either need to have the partition starting point
coded into it, or read the partition table to get it.


| You can then either use a partition or space not belonging to any
| partition. You are not limited to one kernel per partition as you can
| reserve some space in the beginning of your partition for a simple
| table - or for the LILO secondary boot loader and your hand crafted
| LILO map file.

I don't want to land the kernel at some arbitrary sector. I want it
specifically to be in a partition. I don't want to have to re-write
the boot loader to disk to change anything besides which partition
number is the default.

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / spamtrap-2006-10-19-1419@xxxxxxxx |
|------------------------------------/-------------------------------------|
.

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