diff --git a/pkgs/os-specific/linux/ax99100/default.nix b/pkgs/os-specific/linux/ax99100/default.nix
index 91999c0113c6..761800cfd7ba 100644
--- a/pkgs/os-specific/linux/ax99100/default.nix
+++ b/pkgs/os-specific/linux/ax99100/default.nix
@@ -28,6 +28,7 @@ stdenv.mkDerivation {
     ./kernel-6.1-set_termios-const-ktermios.patch
   ] ++ lib.optionals (lib.versionAtLeast kernel.version "6.2") [
     ./kernel-6.2-fix-pointer-type.patch
+    ./kernel-6.4-fix-define-semaphore.patch
   ];
 
   patchFlags = [ "-p0" ];
diff --git a/pkgs/os-specific/linux/ax99100/kernel-6.4-fix-define-semaphore.patch b/pkgs/os-specific/linux/ax99100/kernel-6.4-fix-define-semaphore.patch
new file mode 100644
index 000000000000..434bb559e177
--- /dev/null
+++ b/pkgs/os-specific/linux/ax99100/kernel-6.4-fix-define-semaphore.patch
@@ -0,0 +1,14 @@
+--- ax99100_sp.c
++++ ax99100_sp.c
+@@ -2670,8 +2670,10 @@ static void serial99100_dma_tx_tasklet (unsigned long param)
+ 
+ #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37)
+ static DECLARE_MUTEX(serial99100_sem);
+-#else
++#elif LINUX_VERSION_CODE < KERNEL_VERSION(6,4,0)
+ static DEFINE_SEMAPHORE(serial99100_sem);
++#else
++static DEFINE_SEMAPHORE(serial99100_sem, 1);
+ #endif
+ 
+ static struct uart_driver starex_serial_driver = {