When start Vbox getting KVM error

[kermit2030]

Before I installed virtualbox from the website (2.1.4 for Ubuntu linux 8.10 64 bit I read on the internet that I needed KVM

So I did aptitude install dkms
Then I installed the virtual box 2.1.4 and intalled 32 bit Windows vista Ultimate on it . After doing that I shut down the windows and tried to restart the virutalbox and it gave me the following error.


VirtualBox can't operate in VMX root mode. Please disable the KVM kernel extension, recompile your kernel and reboot (VERR_VMX_IN_VMX_ROOT_MODE).


Result Code:
NS_ERROR_FAILURE (0x80004005)
Component:
Console
Interface:
IConsole {e3c6d4a1-a935-47ca-b16d-f9e9c496e53e}

I did a apittude remove dkms
and tried to start virtual box and got the same error.

I remove virtual box and reinstalled it and got the same error.

How do I correct this problem? I don't know how to recompile the kernal like it says?

Your help would be greatly appreciated.

[johnleo]

I think you're seeing a conflict between KVM and VirtualBox.

Try removing the kvm module before starting VirtualBox:

Code: Select all

sudo rmmod kvm-intel

or for host with AMD processor:

Code: Select all

sudo rmmod kvm-amd

[Sasquatch]

KVM is a virtualization of it's own. Just like Xen, VB can't work on that kernel.

[kermit2030]

Thank you so much this fixed my problem and I am up and running now. And it was such an easy painless fix.

God bless you.

[AntiMatter]

Hi,

What is the exact effects of the commands rmmod kvm-intel or rmmod kvm-amd ?
1. Disable KVM to allow VirtualBox to run
2. Allow both KVM and VirtualBox to run

If the answer is 1, then how to enable KVM back gain?

[baf]

What is the exact effects of the commands rmmod kvm-intel or rmmod kvm-amd ?

It unloads those modules from your kernel until your next reboot.

1. Disable KVM to allow VirtualBox to run

either those rmmod lines to do it on the fly or find where they are loaded. /etc/init.d/kvm ? /etc/modprobe? somewhere like that.

2. Allow both KVM and VirtualBox to run

Sorry not possible.

If the answer is 1, then how to enable KVM back gain?

If you just used rmmod then either reboot or modprobe kvm-intel and/or modprobe kvm-amd
Virtualbox probably has some modules like it so look at the output from lsmod and see what they are.
Also check with ps auxww what processes are running.

[AntiMatter]

If you just used rmmod then either reboot or modprobe kvm-intel and/or modprobe kvm-amd
Virtualbox probably has some modules like it so look at the output from lsmod and see what they are.
Also check with ps auxww what processes are running.

Oh crap, if KVM and VirtualBox are installed in the same machine, then each time I want to run one I have to disable/unload the other? I will experiment KVM soon so I would like to make sure to know the troubles beforehand. From what I found on the Internet, I see more often KVM blocking VirtualBox, not the opposite.

If you have used both KVM and VirtualBox on the same machine, what is your recommendation to keep both working? Only one working at a time is fine. I have no need to have both of them run at the same time.

Thanks in advance.

[Brausepaul]

Can someone point me to the place where these modules are loaded? I'd like to permanently prohibit them being loaded.

[Sasquatch]

Modules are loaded and/or blacklisted in /etc/modprobe.d/blacklist. Exact file might differ on other distro's, as this is the file on Debian based ones.

Antimatter, you can make a script to start VB which would unload the module before starting the GUI (or just make a script to enable/disable KVM). Another thing you can do is have two kernel configs, one that allows the KVM module, the other disallows the module. You will then just reboot to the proper kernel for either KVM or VB.

[pearsonbe]

After upgrading from Kubuntu Lucid to Lucid Lynx 10 LTS, an existing Windows XP machine would not start until I disabled Hardware Acceleration (AMD-V). If the machine state is Saved (not Powered Off), you can't change the settings. You will have to unload the KVM module (using the command rmmod kvm-amd for AMD processor) to start the machine, then power it off. Losing Hardware Acceleration also meant I lost support for multiple virtual CPUs. I had to revert to a single CPU before disabling acceleration.

[Sasquatch]

Yes, that is true, because the KVM modules lock the hardware assisted virtualisation option of the CPU. VB will then work in software mode. Since you don't use KVM, you can just remove the KVM related packages.

[abdulazizalmass]

I only registered just to say thank you ALL for this info ^_^