On Thu, Jul 14, 2011 at 02:29:36PM +0300, Avi Kivity wrote: > On 07/13/2011 06:32 PM, Joerg Roedel wrote: >> This saves copying over the vmload/vmsave switched part from >> the host to the guest vmcb later. >> >> Signed-off-by: Joerg Roedel<joerg.roedel@xxxxxxx> >> --- >> arch/x86/kvm/svm.c | 7 ++++++- >> 1 files changed, 6 insertions(+), 1 deletions(-) >> >> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c >> index 3d5990f..dc703ac 100644 >> --- a/arch/x86/kvm/svm.c >> +++ b/arch/x86/kvm/svm.c >> @@ -3704,9 +3704,13 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu) >> >> /* Enter guest mode */ >> "push %%"R"ax \n\t" >> - "mov %c[vmcb](%[svm]), %%"R"ax \n\t" >> + "mov %c[host_vmcb](%[svm]), %%"R"ax \n\t" >> __ex(SVM_VMLOAD) "\n\t" >> + "mov (%%"R"sp), %%"R"ax\n\t" >> + "mov %c[vmcb](%[svm]), %%"R"ax \n\t" >> __ex(SVM_VMRUN) "\n\t" >> + "mov (%%"R"sp), %%"R"ax\n\t" >> + "mov %c[host_vmcb](%[svm]), %%"R"ax \n\t" >> __ex(SVM_VMSAVE) "\n\t" >> "pop %%"R"ax \n\t" >> > > Okay, so the plan is to split L2 state between ->vmcb and ->host_vmcb? Yes, otherwise we need to copy the vmload/vmsave switched state back and forth between both VMCBs which is a waste of cycles. > In that case my suggestion for patch 1 doesn't apply. But the name > still is confusing. If we don't find a better one, I want a fat comment > explaining how state is split. Hmm, how about naming them l1_vmcb and l2_vmcb? The comment explaining why vmload/vmsave always happens on l1_vmcb is needed anyway then. > (would be good to have documentation for the overall strategy of nsvm, > like we have for nvmx and nmmu). There is not much to document about future plans for nested-svm. At the moment I try to add emulation code for new SVM features when there is some time left. Live migration support is also on the list. The long-term plan is certainly to merge code with nested-vmx where possible and move logic into generic KVM code. The first item that comes to mind here is to create a single place where a vmexit is emulated and let all other place which do that today just signal that it is required. Joerg -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
