VirtualBox Critical Error (Guru Meditation)

[AccidentReport]

Yay! So about a week and a bit ago my VirtualBox VMs started crashing for no obvious reason. These are VMs I've had happily running for the last year and a bit. Every night my test scripts fire up and run a set on test on different environments testing a web application on different browsers. There have not been any changes to the software on the VMs and the host machine has had a few windows patches installed but nothing major that I've aware of. I've so far tried rebooting everything cleanly, updating VB to the newest build and various other checks to see if anything has messed up but so far nothing has changed. It appears to be a time related thing so that once the VM has been on for a while it just crashes. Even if it's just idle.

Has anyone got any ideas? I've attached the screenshot and logs that VB produced. I've had a look but don't know what I'm looking for so I'd appreciate any help.

[michaln]

Something in the system must have changed. Given the nature of the error (VERR_VMX_INVALID_VMXON_PTR) it's unlikely to have been anything in the guest. Unless the hardware is going bad (not likely but should never be discounted), there must be some new/different software on the host. Based on what you said, it wasn't a VirtualBox change that triggered it... but what was it?

The short story is that it's not obvious that this is a bug in VirtualBox at all so it may or may not be something we can fix. It would really help if you could figure out what triggered this behavior. If not new software installed on the host, perhaps some update? Any idea?

[Ramshankar]

Is there any other application on your Windows host that might be interfering with VT-x while VirtualBox is running?

[AccidentReport]

Not sure about update as the PC is corporate controlled so it automatically has various software updates and patches pushed to it. The box itself has no other function than to run the tests so I haven't personally installed anything new. I'll have a poke around and see if I can tell what has been installed and when but even if I do I won't be able to remove it. Eliminating VB as the source of the issue is good though as it may mean a rebuild of the host and then putting the current VMs back in after may resolve it.

[michaln]

FYI, this may or may not be the same problem: https://www.virtualbox.org/ticket/14088 I hesitate to call it a duplicate because the creator of the ticket provided very little information.

For reference, it would be good to know what the previous (initially working, later broken) version of VirtualBox was. Also, do you know when (rough date) it broke?

The error you got unfortunately has several possible causes and it could be triggered a bug in VirtualBox (but then we'd expect to see a lot more problem reports) or some 3rd party software manipulating the VT-x state on the host. Intel made it surprisingly difficult to distinguish the possible causes of the error.