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authorJakub Kicinski <kuba@kernel.org>2021-12-17 03:13:19 +0300
committerJakub Kicinski <kuba@kernel.org>2021-12-17 03:13:19 +0300
commit7cd2802d7496c1fc76f42dc045b48cc16d11df39 (patch)
tree41c33f5944bbc686a489801762eb126e07049b81 /arch/x86/kvm/vmx/vmx.c
parent0f473bb6ed2d0b8533a079ee133f625f83de5315 (diff)
parent6441998e2e37131b0a4c310af9156d79d3351c16 (diff)
downloadlinux-7cd2802d7496c1fc76f42dc045b48cc16d11df39.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'arch/x86/kvm/vmx/vmx.c')
-rw-r--r--arch/x86/kvm/vmx/vmx.c22
1 files changed, 13 insertions, 9 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 9453743ce0c4..5aadad3e7367 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2646,15 +2646,6 @@ int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
if (!loaded_vmcs->msr_bitmap)
goto out_vmcs;
memset(loaded_vmcs->msr_bitmap, 0xff, PAGE_SIZE);
-
- if (IS_ENABLED(CONFIG_HYPERV) &&
- static_branch_unlikely(&enable_evmcs) &&
- (ms_hyperv.nested_features & HV_X64_NESTED_MSR_BITMAP)) {
- struct hv_enlightened_vmcs *evmcs =
- (struct hv_enlightened_vmcs *)loaded_vmcs->vmcs;
-
- evmcs->hv_enlightenments_control.msr_bitmap = 1;
- }
}
memset(&loaded_vmcs->host_state, 0, sizeof(struct vmcs_host_state));
@@ -6842,6 +6833,19 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu)
if (err < 0)
goto free_pml;
+ /*
+ * Use Hyper-V 'Enlightened MSR Bitmap' feature when KVM runs as a
+ * nested (L1) hypervisor and Hyper-V in L0 supports it. Enable the
+ * feature only for vmcs01, KVM currently isn't equipped to realize any
+ * performance benefits from enabling it for vmcs02.
+ */
+ if (IS_ENABLED(CONFIG_HYPERV) && static_branch_unlikely(&enable_evmcs) &&
+ (ms_hyperv.nested_features & HV_X64_NESTED_MSR_BITMAP)) {
+ struct hv_enlightened_vmcs *evmcs = (void *)vmx->vmcs01.vmcs;
+
+ evmcs->hv_enlightenments_control.msr_bitmap = 1;
+ }
+
/* The MSR bitmap starts with all ones */
bitmap_fill(vmx->shadow_msr_intercept.read, MAX_POSSIBLE_PASSTHROUGH_MSRS);
bitmap_fill(vmx->shadow_msr_intercept.write, MAX_POSSIBLE_PASSTHROUGH_MSRS);