Bug 34508

Summary: [grub x86_64-efi] Macbook 5,2 - conflicting fb hw usage nouveaufb vs EFI VGA - removing generic driver
Product: xorg Reporter: Gregory Bellier <dest>
Component: Driver/nouveauAssignee: Nouveau Project <nouveau>
Status: RESOLVED FIXED QA Contact: Xorg Project Team <xorg-team>
Severity: critical    
Priority: highest CC: dest, homyur
Version: unspecified   
Hardware: x86-64 (AMD64)   
OS: Linux (All)   
i915 platform: i915 features:
Description Flags
Error when booting none

Description Gregory Bellier 2011-02-20 14:14:24 UTC
I have a MacBook 5,2 equiped with a Nvidia 9400M. On this machine, I have the following bug https://bugs.launchpad.net/acpi/+bug/341230 which is also reported here : http://bugzilla.kernel.org/show_bug.cgi?id=13170

Basically, due to this bug, the OS doesn't boot unless the option maxcpus=1 is set in grub2. Some people say they managed to have both cores when they built grub2 for x86_64 for efi.

This is what I've done with grub2 1.99rc1. I run Ubuntu 10.10 Desktop 64bits.
I managed to boot the kernel but when the timestamp is at ~2 seconds, I hit a bug with this error: "fb: conflicting fb hw usage nouveaufb vs EFI VGA - removing generic driver".

The screen freezes except the top which has a sort of green-ish square overlay. From there, the only thing I can do is to turn the computer off.

I did some googling but I haven't come accross a similar problem. Maybe https://bugs.freedesktop.org/show_bug.cgi?id=29171 is a start.

Please tell me how I could provide more informations. I don't experience this bug when I boot the kernel from grub in a "BIOS-way".
Comment 1 Gregory Bellier 2011-02-21 08:10:08 UTC
Created attachment 43609 [details]
Error when booting
Comment 2 Gregory Bellier 2011-03-09 08:56:45 UTC
Ok, I confirm there is a problem with Nouveau. As soon as I installed the Nvidia binary, I've been able to boot with refit + grub-efi_x86_64.

insmod efi_gop has to be added in the grub entry to be able to boot, like this :

menuentry 'Linux without bios dump' {
        insmod efi_gop
        search --no-floppy --fs-uuid --set=root d5175c18-7da2-49a9-a3af-844bad27c91d
        linux   /vmlinuz root=UUID=d5175c18-7da2-49a9-a3af-844bad27c91d ro
        initrd  /initrd.img
Comment 3 Pekka Paalanen 2011-03-11 11:58:00 UTC
(In reply to comment #0)
> I hit a
> bug with this error: "fb: conflicting fb hw usage nouveaufb vs EFI VGA -
> removing generic driver".

FWIW, that message is not an error in itself, the system is simply doing the right thing: a generic driver (efifb) is being kicked out, so a hardware-specific driver (nouveau) can start driving the hardware.
Comment 4 Gregory Bellier 2011-03-14 10:16:01 UTC
Hmmm ok then. I would prefer to use the open source driver instead of nvidia's but in this case, I have no choice.

What could I do to print a proper error ?
Comment 5 Gregory Bellier 2011-04-06 05:44:38 UTC
I did my tests with a 2.6.35 kernel. I built a custom kernel based on and it works. Meaning, I can successfully boot on Linux when Nouveau and Grub-EFI are involved.

This is a relief. Now I can drop NVidia binary ...

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.