diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index ed95f53..633d68f 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -386,6 +386,7 @@ struct kvm_vcpu_arch {
 #endif
 	u32 vrsave; /* also USPRG0 */
 	u32 mmucr;
+	/* shadow_msr is unused for BookE HV */
 	ulong shadow_msr;
 	ulong csrr0;
 	ulong csrr1;