diff --git a/third_party/linux/external.bzl b/third_party/linux/external.bzl
new file mode 100644
index 0000000..5f25243
--- /dev/null
+++ b/third_party/linux/external.bzl
@@ -0,0 +1,35 @@
+#  Copyright 2020 The Monogon Project Authors.
+#
+#  SPDX-License-Identifier: Apache-2.0
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+def linux_external(name, version):
+    sums = {
+        "5.4.7": "abc9b21d9146d95853dac35f4c4489a0199aff53ee6eee4b0563d1b37079fcc9",
+    }
+    http_archive(
+        name = name,
+        build_file = "//third_party/linux/external:BUILD.repo",
+        patch_args = ["-p1"],
+        patches = [
+            # Enable built-in cmdline for efistub
+            "//third_party/linux/external:0001-x86-Allow-built-in-command-line-to-work-in-early-ker.patch",
+        ],
+        sha256 = sums[version],
+        strip_prefix = "linux-" + version,
+        urls = ["https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-%s.tar.xz" % version],
+    )
+