| Message ID | 1367823872-25895-1-git-send-email-jun.nakajima@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 2013-05-06 09:04, Jun Nakajima wrote: > Recent KVM, since http://kerneltrap.org/mailarchive/linux-kvm/2010/5/2/6261577 > switch the EFER MSR when EPT is used and the host and guest have different > NX bits. So if we add support for nested EPT (L1 guest using EPT to run L2) > and want to be able to run recent KVM as L1, we need to allow L1 to use this > EFER switching feature. > > To do this EFER switching, KVM uses VM_ENTRY/EXIT_LOAD_IA32_EFER if available, > and if it isn't, it uses the generic VM_ENTRY/EXIT_MSR_LOAD. This patch adds > support for the former (the latter is still unsupported). > > Nested entry and exit emulation (prepare_vmcs_02 and load_vmcs12_host_state, > respectively) already handled VM_ENTRY/EXIT_LOAD_IA32_EFER correctly. So all > that's left to do in this patch is to properly advertise this feature to L1. > > Note that vmcs12's VM_ENTRY/EXIT_LOAD_IA32_EFER are emulated by L0, by using > vmx_set_efer (which itself sets one of several vmcs02 fields), so we always > support this feature, regardless of whether the host supports it. > > Signed-off-by: Nadav Har'El <nyh@il.ibm.com> > Signed-off-by: Jun Nakajima <jun.nakajima@intel.com> > Signed-off-by: Xinhao Xu <xinhao.xu@intel.com> > --- > arch/x86/kvm/vmx.c | 18 ++++++++++++++---- > 1 file changed, 14 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index 867b810..485ded6 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -2057,6 +2057,7 @@ static __init void nested_vmx_setup_ctls_msrs(void) > #else > nested_vmx_exit_ctls_high = 0; > #endif > + nested_vmx_exit_ctls_high |= VM_EXIT_LOAD_IA32_EFER; You are using the wrong baseline. This does not apply against next. Please fix (you can find the properly rebased version in my tree). Thanks, Jan
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 867b810..485ded6 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2057,6 +2057,7 @@ static __init void nested_vmx_setup_ctls_msrs(void) #else nested_vmx_exit_ctls_high = 0; #endif + nested_vmx_exit_ctls_high |= VM_EXIT_LOAD_IA32_EFER; /* entry controls */ rdmsr(MSR_IA32_VMX_ENTRY_CTLS, @@ -2064,6 +2065,7 @@ static __init void nested_vmx_setup_ctls_msrs(void) nested_vmx_entry_ctls_low = 0; nested_vmx_entry_ctls_high &= VM_ENTRY_LOAD_IA32_PAT | VM_ENTRY_IA32E_MODE; + nested_vmx_entry_ctls_high |= VM_ENTRY_LOAD_IA32_EFER; /* cpu-based controls */ rdmsr(MSR_IA32_VMX_PROCBASED_CTLS, @@ -7050,10 +7052,18 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) vcpu->arch.cr0_guest_owned_bits &= ~vmcs12->cr0_guest_host_mask; vmcs_writel(CR0_GUEST_HOST_MASK, ~vcpu->arch.cr0_guest_owned_bits); - /* Note: IA32_MODE, LOAD_IA32_EFER are modified by vmx_set_efer below */ - vmcs_write32(VM_EXIT_CONTROLS, - vmcs12->vm_exit_controls | vmcs_config.vmexit_ctrl); - vmcs_write32(VM_ENTRY_CONTROLS, vmcs12->vm_entry_controls | + /* L2->L1 exit controls are emulated - the hardware exit is to L0 so + * we should use its exit controls. Note that IA32_MODE, LOAD_IA32_EFER + * bits are further modified by vmx_set_efer() below. + */ + vmcs_write32(VM_EXIT_CONTROLS, vmcs_config.vmexit_ctrl); + + /* vmcs12's VM_ENTRY_LOAD_IA32_EFER and VM_ENTRY_IA32E_MODE are + * emulated by vmx_set_efer(), below. + */ + vmcs_write32(VM_ENTRY_CONTROLS, + (vmcs12->vm_entry_controls & ~VM_ENTRY_LOAD_IA32_EFER & + ~VM_ENTRY_IA32E_MODE) | (vmcs_config.vmentry_ctrl & ~VM_ENTRY_IA32E_MODE)); if (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_PAT)