Re: KVM crash on unusual PM->RM transition

H. Peter Anvin
2009-04-14T05:42:58Z

> The current test branch of Syslinux does PM->RM transition via a stub
> which can be located in high memory. This is correct and valid (x86
> CPUs rely on this to boot): after clearing CR0.PE, CS.base retains its
> previous value until CS is reloaded by a far JMP (which in this case is
> the very next instruction).

Some trivial research later...

It looks like KVM will simply crash when it runs into a real-mode state
it can't approximate with V86 mode. I guess I had the failed notion
that it would kick back such "impossible" states to Qemu.