KVM: nVMX: Drop superfluous VMREAD of vmcs02.GUEST_SYSENTER_*

Don't propagate GUEST_SYSENTER_* from vmcs02 to vmcs12 on nested VM-Exit
as the vmcs12 fields are updated in vmx_set_msr(), and writes to the
corresponding MSRs are always intercepted by KVM when running L2.

Dropping the propagation was intended to be done in the same commit that
added vmcs12 writes in vmx_set_msr()[1], but for reasons unknown was
only shuffled around[2][3].

[1] https://patchwork.kernel.org/patch/10933215
[2] https://patchwork.kernel.org/patch/10933215/#22682289
[3] https://lore.kernel.org/patchwork/patch/1088643

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200428231025.12766-3-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index b2cd8d39964406f44bd4d65eea8a3d59fcd0142d..135adc6245927f6597c97c237b1350428323956c 100644 (file)
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -3952,10 +3952,6 @@ static void sync_vmcs02_to_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
        vmcs12->guest_cs_ar_bytes = vmcs_read32(GUEST_CS_AR_BYTES);
        vmcs12->guest_ss_ar_bytes = vmcs_read32(GUEST_SS_AR_BYTES);
 
-       vmcs12->guest_sysenter_cs = vmcs_read32(GUEST_SYSENTER_CS);
-       vmcs12->guest_sysenter_esp = vmcs_readl(GUEST_SYSENTER_ESP);
-       vmcs12->guest_sysenter_eip = vmcs_readl(GUEST_SYSENTER_EIP);
-
        vmcs12->guest_interruptibility_info =
                vmcs_read32(GUEST_INTERRUPTIBILITY_INFO);