[SOLVED] HELP! Nouveau prevents me from accessing my desktop

[dclement]

Hi, I'm in trouble. I was trying to test the Nouveau driver instead of Nvidia which gave me issues.

I installed Nouveau with the smxi script (that's how I installed the Nvidia driver before) but something went badly wrong. After restarting, I got no desktop, only a black screen. I can't switch to a console with Ctrl+F1...F6. I'd like to enter the Grub menu, but the shift keys have no effect. I had suppressed the grub timeout (silly me...); I was able to restore it with the help of a live usb key, but of course I couldn't run update-grub from a live session, so it had no effect.

What would you suggest? It would be OK if I just could gain access to a console...

Many thanks in advance - Daniel

[Monsta]

I had suppressed the grub timeout (silly me...); I was able to restore it with the help of a live usb key, but of course I couldn't run update-grub from a live session, so it had no effect.

You can still do it from the live session via chroot. See this page (it's for Ubuntu, but the method works in Debian too).

[dclement]

Thanks for your support, Monsta. I was able to update-grub (I did not reinstall it) with chroot and get the Grub choice of kernels.

Then I choose "recovery mode" for my current kernel, but I end up with this line:

Code: Select all

Give root password for maintenance
(or type Control-D to continue):

but whatever I type (e.g. the beginning of my password) I get

Code: Select all

Incorrect login

as soon as I press just one key, and after that I'm stuck between these two messages...

[dclement]

Update: i finally got past the blocking point thanks to [url=http://mige.blogspot.fr/2011/02/single-user-mode-without-root-password.html]these instructions[/url].

Now I can get to a root shell and verify that smxi or sgfxi can run (by typing its whole path: /usr/bin/smxi). Of course it doesn't go on because there's no WiFi. Now I suppose my best option is to connect a network cable, run smxi/sgfxi, reinstall the Nvidia driver and cross my fingers...

[Monsta]

Update: i finally got past the blocking point thanks to [url=http://mige.blogspot.fr/2011/02/single-user-mode-without-root-password.html]these instructions[/url].

That reminded me that you can add "nomodeset" kernel parameter the same way and see if it helps to restore Ctrl-Alt-Fx functionality.

If nothing helps... well, why not try running sgfxi in a chroot?

[dclement]

That reminded me that you can add "nomodeset" kernel parameter the same way and see if it helps to restore Ctrl-Alt-Fx functionality.

Yes, I have seen this option before, but I did not think it could help there. However, I had my root console...

If nothing helps... well, why not try running sgfxi in a chroot?

Sure, why not, but I do hope it will run from the original console. I'm keeping this as a last resort, because my live USB is LM 15, not LMDE, and I fear it could confuse smxi/sgfxi.

Well, I'm testing this ASAP tonight.

[dclement]

I'm back to report (lucky) success.

1st, smxi would not run from the recovery console, because it failed to see the (wired) network connection. So I was back to chroot from live-USB. But...

2nd, smxi complained that there was some kind of kernel mismatch, and it was looking for kernel 3.8 (not in repos.) while 3.10 was installed. Needless to say, I refused to install any other kernel. I then turned to sgfxi, which agreed to run with the -! 40 option (all kernels). But...

3rd, sgfxi claimed that it was unable to remove/unload Nouveau. It suggested to reboot.

The result at the reboot was unexpected: the Nouveau driver was there, and working. After some routine backups, I was able to run smxi the proper way and reinstall the Nvidia driver. Close escape. I'm in no hurry to try again.

I was not feeling I was doing anything dangerous; the idea was to temporarily use Nouveau only to get the Nvidia driver in sync with the one from the Debian repo. (sgfxi -d did not work). I'll have to be even more cautious in the future:
- It's not enough to have a timeout in Grub if I get no Internet connection in a recovery console,
- There's something wrong between Nouveau and smxi, it shouldn't have left me without any F1...F6 consoles;
- It would be wise if I could make some kind of persistent live-USB key with same kernel version as on my PC.

Thanks again Monsta for your support, the chroot was the solution in the end. I'm trying to tag this thread as solved.

[Monsta]

smxi complained that there was some kind of kernel mismatch, and it was looking for kernel 3.8 (not in repos.) while 3.10 was installed.

Ah, yeah, chroot from Mint 15 Live DVD... Mint 15 has kernel 3.8, and that probably confused smxi

It's good you got it sorted in the end. BTW, you can try mintconstructor to make your own LMDE ISO with the updated packages. I'm not sure about the kernel though. But you can experiment with it, it's safe. [url=http://community.linuxmint.com/tutorial/view/918]This tutorial[/url] will help.

[dclement]

That's VERY interesting! I didn't know Mintconstructor, but I'll sure have a deeper look at it when I have some time.