diff --git a/meta/classes-recipe/kernel-module-split.bbclass b/meta/classes-recipe/kernel-module-split.bbclass
index ab2f0d1c37..bde7cd02dd 100644
--- a/meta/classes-recipe/kernel-module-split.bbclass
+++ b/meta/classes-recipe/kernel-module-split.bbclass
@@ -42,6 +42,27 @@ KERNEL_MODULE_PACKAGE_PREFIX ?= ""
 KERNEL_MODULE_PACKAGE_SUFFIX ?= "-${KERNEL_VERSION}"
 KERNEL_MODULE_PROVIDE_VIRTUAL ?= "1"
 
+def get_ext_mod(d):
+    """
+    Extract the resolved Kbuild M= variable from an out of tree module Makefile variable database.
+    """
+    import re
+    import bb.process
+
+    try:
+        output = bb.process.run(
+            "make -C %s --dry-run --print-data-base" % d.getVar("B")
+        )[0]
+    except bb.process.ExecutionError:
+        return d.getVar("S")
+
+    for line in output.splitlines():
+        m = re.match(r'^M\s*=\s*(.*)$', line)
+        if m:
+            return m.group(1).strip()
+
+    return d.getVar("S")
+
 python split_kernel_module_packages () {
     import re
 
