Intentional Triple Fault causes guru meditation

[Martin Wolters]

I am working on a toy kernel which I test in VirtualBox. If that matters, I use GRUB to boot the kernel. To initiate a reboot, I cause a triple fault with the following code:

mov eax, 0
lidt [eax]
int 1

When I run this code natively, the machine reboots, as intended. In Virtualbox, the VM crashes with a "Guru Meditation" error message.

[Martin Wolters]

Log file

[Sander van Leeuwen]

Triple faults are not handled correctly. They don't cause a crash, but an assertion. Needs to be fixed, but it has a rather low priority.

[Klaus Espenlaub]

Technically speaking the exact reaction to a triple fault is not specified. The Intel/AMD CPU specs say that it triggers a CPU shutdown. It's the job of the other parts of the system (the chipset) to decide what to do, and the usual reaction of the silicon is triggering a system reset. The latter is not done by VirtualBox right now as mentioned before.