diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.hAFAICT, that MSR is being used only in arch/x86/kvm/lapic.c
>index b05402e..605b869 100644
>--- a/arch/x86/include/asm/msr-index.h
>+++ b/arch/x86/include/asm/msr-index.h
>@@ -284,6 +284,7 @@
> #define MSR_AMD64_TSC_RATIO 0xc0000104
> #define MSR_AMD64_NB_CFG 0xc001001f
> #define MSR_AMD64_PATCH_LOADER 0xc0010020
>+#define MSR_AMD64_AVIC_DOORBELL 0xc001011b
Please add it there.