Passing boot options in a USB live situation [SOLVED]

[greatbigdragon]

Hello, I was wondering if someone could help me with their know-how.

I have set up a USB "Pen Drive Linux" on a 4GB flash drive and am trying to get it so that the live part works how I want it to. Unfortunately, the wireless on my laptop requires that I pass this boot option: pci=use_crs . I tried going the normal route - that is, editing /etc/default/grub and putting that option into the CMDLINE DEFAULT spot where it should go - and I saved it, but when I ran "sudo update-grub" it gave the error

grub-probe: error: cannot find a device for /.

I can get the boot option in by pressing Tab in the grub menu and sticking the option into the line somewhere, but I was wondering what I have to edit or do in order to get it in there so I can boot into the Live install every time with that option without having to take the extra step? I can't find grub.conf. I can't find menu.lst. I can't find much of anything, it seems, and I think it has to do with it being a live system on USB.

[Husse]

Which version of Mint?
Probably 8 and it does not have a menu.lst or a grub.conf
How exactly did you change - the line before and after please

[greatbigdragon]

Yes, sorry it's Mint 8 x64 and what I'm trying to do is pass it a specific boot option . . . I tried the "adding the pci=use_crs option to GRUB" in the post http://ubuntuforums.org/showthread.php?t=1336022 . I actually did this post-install on my laptop and it worked like a charm. Now, I'm trying to achieve the same result for the bootable USB version except trying to run update-grub results in the error I mentioned before.

Here's the section of /etc/default/grub that I modified:

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.

GRUB_DEFAULT=0
GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT="10"
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pci=use_crs"
GRUB_CMDLINE_LINUX=""

As you see, I added the "pci=use_crs" in the GRUB_CMDLINE_LINUX_DEFAULT line there and tried to run update-grub, but it doesn't work the same as in an installed system. It gives this error:

grub-probe: error: cannot find a device for /.

What I would like is a persistent method of having this boot option without having to hit tab and putting it in myself when the boot menu comes up (when booting from the USB Live option.)

[Husse]

grub-probe: error: cannot find a device for /

I'm afraid that's something you have to live with - grub is not used on a live system, I should have considered that this was a live system but I did not, to interested in different grubs (if one can say grubs )
There may be another way by changing the boot.img but that's way beyond what I can tell you without quite a bit of research

[remoulder]

What I would like is a persistent method of having this boot option

You could always make your own livecd, see here http://ubuntuforums.org/showthread.php?t=688872

[greatbigdragon]

Ah, I see. So I'm coming at it from the wrong angle. I'll have to look into making a custom live CD, thanks for that link, Remoulder, and thanks for your help Husse.

Does anyone know which file a live USB distro uses to create the boot menu, then?