On 11/22/2010 04:49 PM, Gerd Hoffmann wrote:
On real hardware seabios could emulate this using SMM.
On virtual hardware qemu could emulate this so we don't need SMM support in kvm.
How hard would it be to add SMM support into kvm?
Dunno. As I understand it the biggest issue is that kvm needs complete instruction emulation for big real mode as intel vmx supports protected mode only. Correct Avi?
Correct. Note, it's likely that we have almost everything covered already, so it's mostly testing (beyond implementing SMM entry/exit).
However, we have a large deployed base with no SMM support, so we need a fallback if SMM is not available. It's also tricky to probe for working SMM, I don't think there's a cpuid bit for that.