Re: /boot partition changes when it should not

On Tue, 9 Mar 2010 18:50:59 -0500 (EST), Clive McBarton wrote:
Stephen Powell wrote:
But the
boot loader doesn't know that Linux is going to mount the filesystem
read-only.

That's a highly interesting point. It doesn't? I thought everything in
the boot process mounts everything it finds read-only until when the
kernel is running. Even the kernel at some point during boot says it now
remounts the / filesystem read-write, hence even that must have been
read-only until then.

What I meant by that is that the boot loader does not examine the
/etc/fstab file. In your case, that file is not even in the same
partition as /boot. I don't know if the boot loader alters any fields
in the /boot partition or not. I'm only saying that it might. /boot
is not normally mounted read-only. If it were, one could not apply
security updates to the kernel, for example. The boot loader would not
therefore necessarily assume that it couldn't update the mount count
field, for example. Again, I'm not saying that it does. I only
suggested it as a possibility. And if it does, I don't know if it's
a bug or a feature.

If there's an option in grub, as thib seems to think, that will cause
grub to use the list-of-sectors method rather than actually reading
the filesystem, that would be good to try first. Then if that doesn't
work, you might try lilo. Converting the partition to ext2 to get
rid of the journal or using the noload option are some other things
you can try.


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