From dbee3d02458b129b847c21f5fa60baba3eafc6f7 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 12 Jun 2018 20:28:00 -0700 Subject: [PATCH] KVM: x86: VMX: fix build without hyper-v Commit ceef7d10dfb6 ("KVM: x86: VMX: hyper-v: Enlightened MSR-Bitmap support") broke the build with Hyper-V disabled, because it accesses ms_hyperv.nested_features without checking if that exists. This is the quick-and-hacky build fix. I suspect the proper fix is to replace the static_branch_unlikely(&enable_evmcs) tests with an inline helper function that also checks that CONFIG_HYPERV is enabled, since without that, enable_evmcs makes no sense. But I want a working build environment first and foremost, and I'm upset this slipped through in the first place. My primary build tests missed it because I tend to build with everything enabled, but it should have been caught in the kvm tree. Fixes: ceef7d10dfb6 ("KVM: x86: VMX: hyper-v: Enlightened MSR-Bitmap support") Cc: Vitaly Kuznetsov Cc: Paolo Bonzini Signed-off-by: Linus Torvalds --- arch/x86/kvm/vmx.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index fc61e25966e4..d0dd35d582da 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -4429,6 +4429,7 @@ static int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs) goto out_vmcs; memset(loaded_vmcs->msr_bitmap, 0xff, PAGE_SIZE); +#if IS_ENABLED(CONFIG_HYPERV) if (static_branch_unlikely(&enable_evmcs) && (ms_hyperv.nested_features & HV_X64_NESTED_MSR_BITMAP)) { struct hv_enlightened_vmcs *evmcs = @@ -4436,6 +4437,8 @@ static int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs) evmcs->hv_enlightenments_control.msr_bitmap = 1; } +#endif + } return 0; -- 2.20.1