putting lvm autodetect into the kernel ala md
Quoted 2 lines · Luca Berra
no, [lvm partition detection and activation] is a user space task, there is no reason to burden the kernel with this.
I find that a spurious argument. The kernel autodetects physical partitions, so how is that different from detecting logical ones? From the user's point of view he would want it to happen the same way. In fact, given the flexibility and [purported] negligible overhead of logical volumes, he should not even be bothering with physical partitions anymore.
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reply-to: a n d y @ n e o t i t a n s . c o m
Quoted 11 lines · Andy Sy
Quoted 2 lines · Luca Berra
no, [lvm partition detection and activation] is a user space task, there is no reason to burden the kernel with this.
I find that a spurious argument. The kernel autodetects physical partitions, so how is that different from detecting logical ones?
Quoted 1 line
From the user's point of view he would want it to happen the
same way. In fact, given the flexibility and [purported] negligible overhead of logical volumes, he should not even be bothering with physical partitions anymore.
it adds unneded complexyty to the kernel.
L.
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Luca Berra -- [email protected] Communication Media & Services S.r.l. /"\ \ / ASCII RIBBON CAMPAIGN X AGAINST HTML MAIL / \
Quoted 3 lines · Luca Berra
lilo does not read a partition. all that lilo needs is to be able to create a mapping from a file to the physical sectors on the drive, and guess the BIOS id of that drive.
... and use BIOS (?) to load in the sectors containing the kernel, initrd, etc... before passing off execution to it?
Anyway, now I believe I understand what you were trying to get at earlier:
Quoted 3 lines
confusion between a boot loader (which is the only limitation we have in loading a
kernel/initrd/initramfs) and what the kernel can do.
In order for things to work if /boot resides in a non-physical (e.g. RAID1, RAID0, lvm, etc...), LILO itself has to know how to read the contents of /boot off of that type of partition. Having lvm/md autodetect on the kernel will NOT help LILO (it will, however, eliminate the need for an initrd).
Quoted 3 lines
I insist initrd is not an hassle, it is good programming practice. This means code separation between kernel-space and user space, and the linux kernel is moving _that_ way.
Yes, I do find myself agreeing with your general sentiments. The primary concern, to do away with the need to have a separate /boot partition, is not helped at all if the kernel can autodetect lvm partitions.
Dispensing with the need for an initrd is but a secondary concern, and fact is, I would also say that it brings a lot of flexiblity to the table. So no, having lvm autodetect in the kernel is not what I'm looking for. What we're looking for is good lvm support in LILO.
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reply-to: a n d y @ n e o t i t a n s . c o m
Quoted 6 lines · Andy Sy
Dispensing with the need for an initrd is but a secondary concern, and fact is, I would also say that it brings a lot of flexiblity to the table. So no, having lvm autodetect in the kernel is not what I'm looking for. What we're looking for is good lvm support in LILO.
Christophe patches to lilo help a bit, but there still are limitations.
http://www.saout.de/misc/
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Luca Berra -- [email protected] Communication Media & Services S.r.l. /"\ \ / ASCII RIBBON CAMPAIGN X AGAINST HTML MAIL / \