diff --git a/include/sysemu/hax.h b/include/sysemu/hax.h
index bf8f99a824..80fc716f80 100644
--- a/include/sysemu/hax.h
+++ b/include/sysemu/hax.h
@@ -19,6 +19,8 @@
  *
  */
 
+/* header to be included in non-HAX-specific code */
+
 #ifndef QEMU_HAX_H
 #define QEMU_HAX_H
 
diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index 88f5ccfbce..7902acdfd9 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -11,6 +11,8 @@
  *
  */
 
+/* header to be included in non-KVM-specific code */
+
 #ifndef QEMU_KVM_H
 #define QEMU_KVM_H
 
diff --git a/include/sysemu/nvmm.h b/include/sysemu/nvmm.h
index 833670fccb..be7bc9a62d 100644
--- a/include/sysemu/nvmm.h
+++ b/include/sysemu/nvmm.h
@@ -7,6 +7,8 @@
  * See the COPYING file in the top-level directory.
  */
 
+/* header to be included in non-NVMM-specific code */
+
 #ifndef QEMU_NVMM_H
 #define QEMU_NVMM_H
 
diff --git a/include/sysemu/tcg.h b/include/sysemu/tcg.h
index 53352450ff..5e2ca9aab3 100644
--- a/include/sysemu/tcg.h
+++ b/include/sysemu/tcg.h
@@ -5,6 +5,8 @@
  * See the COPYING file in the top-level directory.
  */
 
+/* header to be included in non-TCG-specific code */
+
 #ifndef SYSEMU_TCG_H
 #define SYSEMU_TCG_H
 
diff --git a/include/sysemu/whpx.h b/include/sysemu/whpx.h
index 2889fa2278..781ca5b2b6 100644
--- a/include/sysemu/whpx.h
+++ b/include/sysemu/whpx.h
@@ -10,6 +10,8 @@
  *
  */
 
+/* header to be included in non-WHPX-specific code */
+
 #ifndef QEMU_WHPX_H
 #define QEMU_WHPX_H
 
diff --git a/include/sysemu/xen.h b/include/sysemu/xen.h
index 0ca25697e4..bc13ad5692 100644
--- a/include/sysemu/xen.h
+++ b/include/sysemu/xen.h
@@ -5,6 +5,8 @@
  * See the COPYING file in the top-level directory.
  */
 
+/* header to be included in non-Xen-specific code */
+
 #ifndef SYSEMU_XEN_H
 #define SYSEMU_XEN_H