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[PATCHv2] kernel-module-split: don't re-sign compressed kernel modules

Message ID 20260916193051.56418-1-f_l_k@t-online.de
State New
Headers show
Series [PATCHv2] kernel-module-split: don't re-sign compressed kernel modules | expand

Commit Message

Markus Volk Sept. 16, 2026, 7:30 p.m. UTC
With CONFIG_MODULE_COMPRESS_ALL the kernel installs modules with a
compression suffix, and scripts/Makefile.modinst derives the compressed
file from the signed uncompressed one, which is removed afterwards.
The modules_sign target then has nothing to sign below ${PKGD} and
do_package fails in sign-file with an openssl "no such file" error.

Re-signing is not needed there either: compressed modules are not ELF
files, so package stripping leaves them alone and the signature made
during modules_install is still valid.

Found on a raspberrypi4-64 kernel, which enables both MODULE_SIG_ALL
and MODULE_COMPRESS_XZ. Tested by building linux-raspberrypi through
do_package, which now packages 1861 signed .ko.xz modules.

AI-Generated: Uses Claude Code
Signed-off-by: Markus Volk <f_l_k@t-online.de>
---
 meta/classes-recipe/kernel-module-split.bbclass | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)
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Patch

diff --git a/meta/classes-recipe/kernel-module-split.bbclass b/meta/classes-recipe/kernel-module-split.bbclass
index 99c2d12962..9a7f04f37b 100644
--- a/meta/classes-recipe/kernel-module-split.bbclass
+++ b/meta/classes-recipe/kernel-module-split.bbclass
@@ -53,8 +53,15 @@  post_strip_kernel_modules_signing(){
     is_modules="$(${STAGING_KERNEL_DIR}/scripts/config --file ${KBUILD_OUTPUT}/.config --state MODULES)"
     is_module_sig="$(${STAGING_KERNEL_DIR}/scripts/config --file ${KBUILD_OUTPUT}/.config --state MODULE_SIG)"
     is_module_sig_all="$(${STAGING_KERNEL_DIR}/scripts/config --file ${KBUILD_OUTPUT}/.config --state MODULE_SIG_ALL)"
-
-    if [ "$is_modules" = "y" ] && [ "$is_module_sig" = "y" ] && [ "$is_module_sig_all" = "y" ]; then
+    is_module_compress_all="$(${STAGING_KERNEL_DIR}/scripts/config --file ${KBUILD_OUTPUT}/.config --state MODULE_COMPRESS_ALL)"
+
+    # Compressed modules are not ELF files, so package stripping leaves them
+    # untouched and the signature made during modules_install is still valid.
+    # Re-signing them is not only unnecessary but fails: with
+    # CONFIG_MODULE_COMPRESS_ALL the install targets carry the compression
+    # suffix, and the uncompressed module their rule depends on does not
+    # exist below ${PKGD}.
+    if [ "$is_modules" = "y" ] && [ "$is_module_sig" = "y" ] && [ "$is_module_sig_all" = "y" ] && [ "$is_module_compress_all" != "y" ]; then
         # Sign modules under ${PKGD}, with M= if out-of-tree module.
         # Out-of-tree module Makefiles invoke the kernel Makefile by appending M= (the module directory) to MAKEFLAGS.
         # However, they usually do not provide a modules_sign target. Therefore, the kernel modules_sign target has to