Completing big real mode emulation

Mohammed Gamal
2010-03-19T15:29:39Z

Hello all,
As some of you might know, I've worked on supporting big real mode
emulation on VMX back in GSoC 2008. Looking at the Qemu GSoC ideas
list for this year, I found it among the possible ideas for a GSoC
project. I'd be interested in driving this feature towards completion,
and I have a few questions about it.

- The kernel-space modifications needed to detect an invalid guest
state on VMX and drive emulation from that point was almost complete.
The part that was missing the most, is that the kvm x86 emulator
wasn't complete and didn't support the entire instruction set. I've
seen that the emulator has been the focus of some recent patches
(namely by Gleb Natapov). Is there anything else required to get big
real mode to work correctly on KVM?

- Do we have other problems supporting big real mode on non-VMX
instruction sets? And do we have problems supporting it on the
userspace side?

- Is there anything I am missing?

Regards,
Mohammed