diff --git a/pkgs/by-name/li/linux-manual/package.nix b/pkgs/by-name/li/linux-manual/package.nix
index d42d30fe531a..dc48ad7a1107 100644
--- a/pkgs/by-name/li/linux-manual/package.nix
+++ b/pkgs/by-name/li/linux-manual/package.nix
@@ -29,6 +29,8 @@ stdenv.mkDerivation {
 
     # avoid Makefile because it checks for unnecessary Python dependencies
     KBUILD_BUILD_TIMESTAMP="$(date -u -d "@$SOURCE_DATE_EPOCH")" \
+    # Expected by the script, default value is '.'
+    srctree="." \
     tools/docs/sphinx-build-wrapper mandocs
 
     runHook postBuild