diff --git a/gentoo-C23.patch b/gentoo-C23.patch
index bcccb45..6ecace2 100644
--- a/gentoo-C23.patch
+++ b/gentoo-C23.patch
@@ -2,13 +2,15 @@ https://bugs.gentoo.org/946955
 
 --- a/include/iprt/types.h
 +++ b/include/iprt/types.h
-@@ -281,8 +281,7 @@
-      typedef _Bool bool;
+@@ -282,7 +282,10 @@
  #   endif
  #  else
 -#   undef bool /* see above netbsd explanation */
--typedef _Bool bool;
-+#   include <stdbool.h>
++#   if defined (__KERNEL__)
+ typedef _Bool bool;
++#   else
++#     include <stdbool.h>
++#   endif
  #  endif
  # else
  #  if RT_MSC_PREREQ(RT_MSC_VER_VC120)
diff --git a/virtualbox.changes b/virtualbox.changes
index 74d5113..7354a71 100644
--- a/virtualbox.changes
+++ b/virtualbox.changes
@@ -1,3 +1,10 @@
+-------------------------------------------------------------------
+Tue Jun  3 16:34:33 UTC 2025 - Martin Jambor <mjambor@suse.com>
+
+- Adjust gentoo-C23.patch to fix building the kmp flavor which was
+  broken by the previous patch by keeping the bool typedef when
+  building a kmp. [boo#1242085]
+
 -------------------------------------------------------------------
 Tue May 27 15:19:29 UTC 2025 - Martin Jambor <mjambor@suse.cz>