Commits
Avi Kivity committed e2a610d7fc3
KVM: VMX: Allow vm86 virtualization of big real mode Usually, big real mode uses large (4GB) segments. Currently we don't virtualize this; if any segment has a limit other than 0xffff, we emulate. But if we set the vmx-visible limit to 0xffff, we can use vm86 to virtualize real mode; if an access overruns the segment limit, the guest will #GP, which we will trap and forward to the emulator. This results in significantly faster execution, and less risk of hitting an unemulated instruction. If the limit is less than 0xffff, we retain the existing behaviour. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>