[PATCH] KVM: x86: VMX: fix building without CONFIG_HYPERV

[Arnd Bergmann]

The global ms_hyperv variable is part of the hyperv support, so
we get a link error from accessing it in kernels that have this
turned off:

arch/x86/kvm/vmx.o: In function `alloc_loaded_vmcs':
vmx.c:(.text+0x1654a): undefined reference to `ms_hyperv'
vmx.c:(.text+0x1657a): undefined reference to `ms_hyperv'

This changes the condition to first check the compile-time
configuration symbol to avoid the link error.

Fixes: ceef7d10dfb6 ("KVM: x86: VMX: hyper-v: Enlightened MSR-Bitmap support")
Signed-off-by: Arnd Bergmann <a...@arndb.de>
---
 arch/x86/kvm/vmx.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ea098131dcce..e6d6ccab43c3 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4232,7 +4232,8 @@ static int alloc_loaded_vmcs(struct loaded_vmcs 
*loaded_vmcs)
                        goto out_vmcs;
                memset(loaded_vmcs->msr_bitmap, 0xff, PAGE_SIZE);
 
-               if (static_branch_unlikely(&enable_evmcs) &&
+               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;
-- 
2.9.0