[PATCH] depmod: Handle installing modules under a prefix

From: Michal Suchanek
Date: Tue Jul 11 2023 - 11:35:08 EST


Some distributions aim at not shipping any files in / ustside of usr.

The path under which kernel modules are instaleld is hardcoded to /lib
which conflicts with this goal.

When kmod provides the config command use it to determine the correct
module installation prefix.

On kmod that does not provide the command / is used as before.

Signed-off-by: Michal Suchanek <msuchanek@xxxxxxx>
---
Makefile | 4 +++-
scripts/depmod.sh | 8 ++++----
2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/Makefile b/Makefile
index 47690c28456a..b05d696f06bd 100644
--- a/Makefile
+++ b/Makefile
@@ -1165,7 +1165,9 @@ export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
# makefile but the argument can be passed to make if needed.
#

-MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
+export KERNEL_MODULE_PREFIX := $(shell kmod config | jq -r .module_prefix)
+
+MODLIB = $(INSTALL_MOD_PATH)$(KERNEL_MODULE_PREFIX)/lib/modules/$(KERNELRELEASE)
export MODLIB

PHONY += prepare0
diff --git a/scripts/depmod.sh b/scripts/depmod.sh
index 3643b4f896ed..88ac79056153 100755
--- a/scripts/depmod.sh
+++ b/scripts/depmod.sh
@@ -27,16 +27,16 @@ fi
# numbers, so we cheat with a symlink here
depmod_hack_needed=true
tmp_dir=$(mktemp -d ${TMPDIR:-/tmp}/depmod.XXXXXX)
-mkdir -p "$tmp_dir/lib/modules/$KERNELRELEASE"
+mkdir -p "$tmp_dir$KERNEL_MODULE_PREFIX/lib/modules/$KERNELRELEASE"
if "$DEPMOD" -b "$tmp_dir" $KERNELRELEASE 2>/dev/null; then
- if test -e "$tmp_dir/lib/modules/$KERNELRELEASE/modules.dep" -o \
- -e "$tmp_dir/lib/modules/$KERNELRELEASE/modules.dep.bin"; then
+ if test -e "$tmp_dir$KERNEL_MODULE_PREFIX/lib/modules/$KERNELRELEASE/modules.dep" -o \
+ -e "$tmp_dir$KERNEL_MODULE_PREFIX/lib/modules/$KERNELRELEASE/modules.dep.bin"; then
depmod_hack_needed=false
fi
fi
rm -rf "$tmp_dir"
if $depmod_hack_needed; then
- symlink="$INSTALL_MOD_PATH/lib/modules/99.98.$KERNELRELEASE"
+ symlink="$INSTALL_MOD_PATH$KERNEL_MODULE_PREFIX/lib/modules/99.98.$KERNELRELEASE"
ln -s "$KERNELRELEASE" "$symlink"
KERNELRELEASE=99.98.$KERNELRELEASE
fi
--
2.41.0