Understanding GRUB_CMDLINE_LINUX_DEFAULT

[jackkk2]

Hello,

I am quite a beginner with Ubuntu which I like very much but does give me severall troubles. I actually use Xubuntu 13.10 and I am running it on a Sony Vaio with a ATI radeon graphic card. The processor is a little old, I am talking about a Intel Core Duo 2.

I need some clarification on the GRUB_CMDLINE_LINUX_DEFAULT line which can be found in the grub file. Basically a few days ago I had the problem that every time I would close the lid of my laptop or the PC would go to suspend when I then would turn the PC on again it would actually reboot and not simply allow me to re-enter in the OS.
To fix this I found that changing

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
to
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_sleep=nonvs"

would solve this.

Later I had another problem, no audio came out from my TV speakers when I would connect my PC to it via HDMI.

To fix this I found that changing:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
to
#GRUB_CMDLINE_LINUX_DEFAULT="quiet splash radeon.audio=1"

would solve it.

Now, of course I seems I need to choose, either having the PC not rebooting everytime it suspends OR having HDMI audio and this is annoying.

So my question is, what exavtly is the GRUB_CMDLINE_LINUX_DEFAULT and how can I keep both lines working together?

Thanks a lot for your help!
Jack

P.S: of course after each grub file editing I always updated the grub via sudo update-grub.

[Toz]

Hello and welcome to the forums. I'm going to move this thread to General Help - it really isn't an Absolute Beginner's type question.

So my question is, what exavtly is the GRUB_CMDLINE_LINUX_DEFAULT and how can I keep both lines working together?

GRUB_CMDLINE_LINUX_DEFAULT contains command line arguments to the linux kernel. You can put as many as you want there provided they are separated by a space. In your case, you could use:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_sleep=nonvs radeon.audio=1"

...and they will all be passed to the kernel.

[Bashing-om]

jackkk2; Hi !

Might try these edits also, and see what results: {always make a backup prior to editing any file}
"GRUB_DEFAULT=0" -> GRUB_DEFAULT=saved
"GRUB_HIDDEN_TIMEOUT=0" -> #GRUB_HIDDEN_TIMEOUT=0 (add a 'comment' character to comment out the line)
"GRUB_HIDDEN_TIMEOUT_QUIET=true -> GRUB_HIDDEN_TIMEOUT_QUIET=false

For full documentation see:
https://help.ubuntu.com/community/Grub2
as a great place to start learning grub.

hope this helps

[jackkk2]

Hello! Thank you both for your help and very fast feedback!
I was pretty sure I had tried what you advised Toz but maybe I didn't wrong earlier, I tried again and it seems to work! At least the PC doesn't reboot after it suspens. I still need to check the HDMI audio on the TV but I am confident.

[Cavsfan]

That is odd. All I have ever had for that line is GRUB_CMDLINE_LINUX_DEFAULT="quiet splash".

I wonder if the fact that you have a radeon video card has anything to do with it. I have an nvidia card.

From Ubuntu 9.04 (Jaunty Jackalope) to Ubuntu 14.04 LTS (Trusty Tahr) and every single version in between all I have ever used is the above command.

[zemega]

I have to edit that line as well on my laptop. It was a problem with keyboard and touchpad not being used in Ubuntu. It has AMD GPU though.