[PATCH v4 17/25] KVM: VMX: Add missing VMEXIT controls to vmcs_config

Vitaly Kuznetsov
2022-07-14T09:16:20Z

As a preparation to reusing the result of setup_vmcs_config() in
nested VMX MSR setup, add the VMEXIT controls which KVM doesn't
use but supports for nVMX to KVM_OPT_VMX_VM_EXIT_CONTROLS and
filter them out in vmx_vmexit_ctrl().

No functional change intended.

Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
arch/x86/kvm/vmx/vmx.c | 4 ++++
arch/x86/kvm/vmx/vmx.h | 3 +++
2 files changed, 7 insertions(+)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index d7170990f469..2fb89bdcbbd8 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4196,6 +4196,10 @@ static u32 vmx_vmexit_ctrl(void)
{
u32 vmexit_ctrl = vmcs_config.vmexit_ctrl;

+ /* Not used by KVM but supported for nesting. */
+ vmexit_ctrl &= ~(VM_EXIT_SAVE_IA32_PAT | VM_EXIT_SAVE_IA32_EFER |
+ VM_EXIT_SAVE_VMX_PREEMPTION_TIMER);
+
if (vmx_pt_mode_is_system())
vmexit_ctrl &= ~(VM_EXIT_PT_CONCEAL_PIP |
VM_EXIT_CLEAR_IA32_RTIT_CTL);
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 89eaab3495a6..e9c392398f1b 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -498,8 +498,11 @@ static inline u8 vmx_get_rvi(void)
#endif
#define KVM_OPT_VMX_VM_EXIT_CONTROLS \
(VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL | \
+ VM_EXIT_SAVE_IA32_PAT | \
VM_EXIT_LOAD_IA32_PAT | \
+ VM_EXIT_SAVE_IA32_EFER | \
VM_EXIT_LOAD_IA32_EFER | \
+ VM_EXIT_SAVE_VMX_PREEMPTION_TIMER | \
VM_EXIT_CLEAR_BNDCFGS | \
VM_EXIT_PT_CONCEAL_PIP | \
VM_EXIT_CLEAR_IA32_RTIT_CTL)
--
2.35.3