[PATCH v2] kbuild: deb-pkg: Don't fail if modules.order is missing

[Matt Fleming <matt@readmodwrite.com>]

From: Matt Fleming <mfleming@cloudflare.com>

Kernels built without CONFIG_MODULES might still want to create -dbg deb
packages but install_linux_image_dbg() assumes modules.order always
exists. This obviously isn't true if no modules were built, so we should
skip reading modules.order in that case.

Fixes: 16c36f8864e3 ("kbuild: deb-pkg: use build ID instead of debug link for dbg package")
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Matt Fleming <mfleming@cloudflare.com>
---
 scripts/package/builddeb | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/scripts/package/builddeb b/scripts/package/builddeb
index 404587fc71fe..9739b0429337 100755
--- a/scripts/package/builddeb
+++ b/scripts/package/builddeb
@@ -96,6 +96,11 @@ install_linux_image_dbg () {
 
 	# Parse modules.order directly because 'make modules_install' may sign,
 	# compress modules, and then run unneeded depmod.
+	modules_file=modules.order
+	if [ ! -s $modules_file ]; then
+		modules_file=/dev/null
+	fi
+
 	while read -r mod; do
 		mod="${mod%.o}.ko"
 		dbg="${pdir}/usr/lib/debug/lib/modules/${KERNELRELEASE}/kernel/${mod}"
@@ -105,7 +110,7 @@ install_linux_image_dbg () {
 		mkdir -p "${dbg%/*}" "${link%/*}"
 		"${OBJCOPY}" --only-keep-debug "${mod}" "${dbg}"
 		ln -sf --relative "${dbg}" "${link}"
-	done < modules.order
+	done < $modules_file
 
 	# Build debug package
 	# Different tools want the image in different locations
-- 
2.34.1