diff mbox series

[kmod,v4,4/4] libkmod, depmod, modprobe: Make directory for kernel modules configurable

Message ID cc04472084dc016679598fcffafc788bbb6d9c0f.1689589902.git.msuchanek@suse.de (mailing list archive)
State New, archived
Headers show
Series kmod /usr support | expand

Commit Message

Michal Suchánek July 17, 2023, 10:39 a.m. UTC
modprobe.d is now searched under ${prefix}/lib, add ${module_directory} to
specify the directory where to search for kernel modules.

With this distributions that do not want to ship files in /lib can also
move kernel modules to /usr while others can keep them in /lib.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
v4: Make the whole path configurable
---
 Makefile.am                          |   3 +-
 configure.ac                         |   7 ++
 libkmod/libkmod.c                    |   4 +-
 man/Makefile.am                      |   1 +
 man/depmod.d.xml                     |   6 +-
 man/depmod.xml                       |   4 +-
 man/modinfo.xml                      |   2 +-
 man/modprobe.xml                     |   2 +-
 man/modules.dep.xml                  |   6 +-
 testsuite/module-playground/Makefile |   2 +-
 testsuite/setup-rootfs.sh            | 109 +++++++++++++++------------
 testsuite/test-depmod.c              |  16 ++--
 testsuite/test-testsuite.c           |   8 +-
 tools/depmod.c                       |   6 +-
 tools/kmod.c                         |   1 +
 tools/modinfo.c                      |   4 +-
 tools/modprobe.c                     |   4 +-
 tools/static-nodes.c                 |   6 +-
 18 files changed, 107 insertions(+), 84 deletions(-)

Comments

Jan Engelhardt July 17, 2023, 7:28 p.m. UTC | #1
On Monday 2023-07-17 12:39, Michal Suchanek wrote:

>modprobe.d is now searched under ${prefix}/lib, add ${module_directory} to
>specify the directory where to search for kernel modules.
>
>With this distributions that do not want to ship files in /lib can also
>move kernel modules to /usr while others can keep them in /lib.

This patch breaks kernel builds/installation.

 * assume $distro has given me a kmod that has your submission included,
   and such kmod was ./configure'd --with-module-directory=/usr/lib/modules

With such a kmod, the module installation of current and past kernels
is not possible, in other words, ** bisecting kernels ** is broken:


$ make modules_install INSTALL_MOD_PATH=$PWD/rt V=1
[...]
# INSTALL /tmp/linux/rt/lib/modules/6.4.3/kernel/virt/lib/irqbypass.ko
  mkdir -p /tmp/linux/rt/lib/modules/6.4.3/kernel/virt/lib/; cp virt/lib/irqbypass.ko /tmp/linux/rt/lib/modules/6.4.3/kernel/virt/lib/irqbypass.ko
[...]
# DEPMOD  /tmp/linux/rt/lib/modules/6.4.3
  sh ./scripts/depmod.sh depmod 6.4.3
depmod: ERROR: could not open directory /tmp/linux/rt/usr/lib/modules/99.98.6.4.3: No such file or directory
depmod: FATAL: could not search modules: No such file or directory
make: *** [Makefile:1956: modules_install] Error 1
Lucas De Marchi July 17, 2023, 8:12 p.m. UTC | #2
On Mon, Jul 17, 2023 at 12:39:53PM +0200, Michal Suchanek wrote:
>modprobe.d is now searched under ${prefix}/lib, add ${module_directory} to
>specify the directory where to search for kernel modules.

I was failing to see the relation of modprobe.d with the module
directory. Maybe reword this slightly?

Now that modprobe.d is searched under ${prefix}/lib, allow a complete
transition to files only under ${prefix} by adding a ${module_directory}
configuration. This specifies the directory where to search for kernel
modules and should match the location where the kernel/distro installs
them.

>
>With this distributions that do not want to ship files in /lib can also
>move kernel modules to /usr while others can keep them in /lib.
>
>Signed-off-by: Michal Suchanek <msuchanek@suse.de>
>---
>v4: Make the whole path configurable
>---
> Makefile.am                          |   3 +-
> configure.ac                         |   7 ++
> libkmod/libkmod.c                    |   4 +-
> man/Makefile.am                      |   1 +
> man/depmod.d.xml                     |   6 +-
> man/depmod.xml                       |   4 +-
> man/modinfo.xml                      |   2 +-
> man/modprobe.xml                     |   2 +-
> man/modules.dep.xml                  |   6 +-
> testsuite/module-playground/Makefile |   2 +-
> testsuite/setup-rootfs.sh            | 109 +++++++++++++++------------
> testsuite/test-depmod.c              |  16 ++--
> testsuite/test-testsuite.c           |   8 +-
> tools/depmod.c                       |   6 +-
> tools/kmod.c                         |   1 +
> tools/modinfo.c                      |   4 +-
> tools/modprobe.c                     |   4 +-
> tools/static-nodes.c                 |   6 +-
> 18 files changed, 107 insertions(+), 84 deletions(-)
>
>diff --git a/Makefile.am b/Makefile.am
>index 7aa5bfa5638d..981574558c93 100644
>--- a/Makefile.am
>+++ b/Makefile.am
>@@ -20,6 +20,7 @@ AM_CPPFLAGS = \
> 	-I$(top_srcdir) \
> 	-DSYSCONFDIR=\""$(sysconfdir)"\" \
> 	-DPREFIX=\""$(prefix)"\" \
>+	-DMODULE_DIRECTORY=\""$(module_directory)"\" \
> 	${zlib_CFLAGS}
>
> AM_CFLAGS = $(OUR_CFLAGS)
>@@ -220,7 +221,7 @@ EXTRA_DIST += testsuite/setup-rootfs.sh
> MODULE_PLAYGROUND = testsuite/module-playground
> ROOTFS = testsuite/rootfs
> ROOTFS_PRISTINE = $(top_srcdir)/testsuite/rootfs-pristine
>-CREATE_ROOTFS = $(AM_V_GEN) $(top_srcdir)/testsuite/setup-rootfs.sh $(ROOTFS_PRISTINE) $(ROOTFS) $(MODULE_PLAYGROUND) $(top_builddir)/config.h $(sysconfdir)
>+CREATE_ROOTFS = $(AM_V_GEN) MODULE_DIRECTORY=$(module_directory) $(top_srcdir)/testsuite/setup-rootfs.sh $(ROOTFS_PRISTINE) $(ROOTFS) $(MODULE_PLAYGROUND) $(top_builddir)/config.h $(sysconfdir)
>
> build-module-playground:
> 	$(AM_V_GEN)if test "$(top_srcdir)" != "$(top_builddir)"; then \
>diff --git a/configure.ac b/configure.ac
>index 6064dee77ae6..a195c8e6b554 100644
>--- a/configure.ac
>+++ b/configure.ac
>@@ -84,6 +84,12 @@ AC_ARG_WITH([rootlibdir],
>         [], [with_rootlibdir=$libdir])
> AC_SUBST([rootlibdir], [$with_rootlibdir])
>
>+# Ideally this would be $prefix/lib/modules but default to /lib/modules for compatibility with earlier versions
>+AC_ARG_WITH([module_directory],
>+        AS_HELP_STRING([--with-module-directory=DIR], [directory in which to look for kernel modules - typically '/lib/modules' or '${prefix}/lib/modules']),
>+        [], [with_module_directory=/lib/modules])
>+AC_SUBST([module_directory], [$with_module_directory])
>+
> AC_ARG_WITH([zstd],
> 	AS_HELP_STRING([--with-zstd], [handle Zstandard-compressed modules @<:@default=disabled@:>@]),
> 	[], [with_zstd=no])
>@@ -304,6 +310,7 @@ AC_MSG_RESULT([
> 	$PACKAGE $VERSION
> 	=======
>
>+	module_directory:	${module_directory}
> 	prefix:			${prefix}
> 	sysconfdir:		${sysconfdir}
> 	libdir:			${libdir}
>diff --git a/libkmod/libkmod.c b/libkmod/libkmod.c
>index f3139c1cef97..d2ed8748c833 100644
>--- a/libkmod/libkmod.c
>+++ b/libkmod/libkmod.c
>@@ -209,7 +209,7 @@ static int log_priority(const char *priority)
> 	return 0;
> }
>
>-static const char *dirname_default_prefix = "/lib/modules";
>+static const char *dirname_default_prefix = MODULE_DIRECTORY;
>
> static char *get_kernel_release(const char *dirname)
> {
>@@ -231,7 +231,7 @@ static char *get_kernel_release(const char *dirname)
> /**
>  * kmod_new:
>  * @dirname: what to consider as linux module's directory, if NULL
>- *           defaults to /lib/modules/`uname -r`. If it's relative,
>+ *           defaults to ${module_prefix}/lib/modules/`uname -r`. If it's relative,
>  *           it's treated as relative to the current working directory.
>  *           Otherwise, give an absolute dirname.
>  * @config_paths: ordered array of paths (directories or files) where
>diff --git a/man/Makefile.am b/man/Makefile.am
>index ad07c30bbd24..25c2cc6fdf13 100644
>--- a/man/Makefile.am
>+++ b/man/Makefile.am
>@@ -22,6 +22,7 @@ CLEANFILES = $(dist_man_MANS)
> 	else \
> 		sed -e '/@PREFIX@/d' $< ; \
> 	fi | \
>+	sed -e 's|@MODULE_DIRECTORY@|$(module_directory)|g' | \
> 	$(XSLT) \
> 		-o $@ \
> 		--nonet \
>diff --git a/man/depmod.d.xml b/man/depmod.d.xml
>index 431ebca6654b..676977c69a4f 100644
>--- a/man/depmod.d.xml
>+++ b/man/depmod.d.xml
>@@ -70,7 +70,7 @@
>         </term>
>         <listitem>
>           <para>
>-            This allows you to specify the order in which /lib/modules
>+            This allows you to specify the order in which @MODULE_DIRECTORY@
>             (or other configured module location) subdirectories will
>             be processed by <command>depmod</command>. Directories are
>             listed in order, with the highest priority given to the
>@@ -101,7 +101,7 @@
>             <command>depmod</command> command. It is possible to
>             specify one kernel or all kernels using the * wildcard.
>             <replaceable>modulesubdirectory</replaceable> is the
>-            name of the subdirectory under /lib/modules (or other
>+            name of the subdirectory under @MODULE_DIRECTORY@ (or other
>             module location) where the target module is installed.
>           </para>
>           <para>
>@@ -110,7 +110,7 @@
>             specifying the following command: "override kmod * extra".
>             This will ensure that any matching module name installed
>             under the <command>extra</command> subdirectory within
>-            /lib/modules (or other module location) will take priority
>+            @MODULE_DIRECTORY@ (or other module location) will take priority
>             over any likenamed module already provided by the kernel.
>           </para>
>         </listitem>
>diff --git a/man/depmod.xml b/man/depmod.xml
>index 3b0097184fd7..fce2a4a67a89 100644
>--- a/man/depmod.xml
>+++ b/man/depmod.xml
>@@ -80,7 +80,7 @@
>     </para>
>     <para> <command>depmod</command> creates a list of module dependencies by
>       reading each module under
>-      <filename>/lib/modules/</filename><replaceable>version</replaceable> and
>+      <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable> and
>       determining what symbols it exports and what symbols it needs.  By
>       default, this list is written to <filename>modules.dep</filename>, and a
>       binary hashed version named <filename>modules.dep.bin</filename>, in the
>@@ -141,7 +141,7 @@
>         <listitem>
>           <para>
>             If your modules are not currently in the (normal) directory
>-            <filename>/lib/modules/</filename><replaceable>version</replaceable>,
>+            <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable>,
>             but in a staging area, you can specify a
>             <replaceable>basedir</replaceable> which is prepended to the
>             directory name.  This <replaceable>basedir</replaceable> is
>diff --git a/man/modinfo.xml b/man/modinfo.xml
>index 9fe0324a2527..b6c4d6045829 100644
>--- a/man/modinfo.xml
>+++ b/man/modinfo.xml
>@@ -54,7 +54,7 @@
>       <command>modinfo</command> extracts information from the Linux Kernel
>       modules given on the command line.  If the module name is not a filename,
>       then the
>-      <filename>/lib/modules/</filename><replaceable>version</replaceable>
>+      <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable>
>       directory is searched, as is also done by
>       <citerefentry><refentrytitle>modprobe</refentrytitle><manvolnum>8</manvolnum></citerefentry>
>       when loading kernel modules.
>diff --git a/man/modprobe.xml b/man/modprobe.xml
>index 91f9e27997cd..4d1fd59c000b 100644
>--- a/man/modprobe.xml
>+++ b/man/modprobe.xml
>@@ -78,7 +78,7 @@
>       is no difference between _ and - in module names (automatic
>       underscore conversion is performed).
>       <command>modprobe</command> looks in the module directory
>-      <filename>/lib/modules/`uname -r`</filename> for all
>+      <filename>@MODULE_DIRECTORY@/`uname -r`</filename> for all
>       the modules and other files, except for the optional
>       configuration files in the
>       <filename>/etc/modprobe.d</filename> directory
>diff --git a/man/modules.dep.xml b/man/modules.dep.xml
>index ed633694ec9e..8ef6d8b3536e 100644
>--- a/man/modules.dep.xml
>+++ b/man/modules.dep.xml
>@@ -34,8 +34,8 @@
>   </refnamediv>
>
>   <refsynopsisdiv>
>-    <para><filename>/lib/modules/modules.dep</filename></para>
>-    <para><filename>/lib/modules/modules.dep.bin</filename></para>
>+    <para><filename>@MODULE_DIRECTORY@/modules.dep</filename></para>
>+    <para><filename>@MODULE_DIRECTORY@/modules.dep.bin</filename></para>
>   </refsynopsisdiv>
>
>   <refsect1><title>DESCRIPTION</title>
>@@ -43,7 +43,7 @@
>       <filename>modules.dep.bin</filename> is a binary file generated by
>       <command>depmod</command> listing the dependencies for
>       every module in the directories under
>-      <filename>/lib/modules/</filename><replaceable>version</replaceable>.
>+      <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable>.
>       It is used by kmod tools such as <command>modprobe</command> and
>       libkmod.
>     </para>
>diff --git a/testsuite/module-playground/Makefile b/testsuite/module-playground/Makefile
>index e6045b0dd932..a7ab09bea2bf 100644
>--- a/testsuite/module-playground/Makefile
>+++ b/testsuite/module-playground/Makefile
>@@ -47,7 +47,7 @@ endif
>
> else
> # normal makefile
>-KDIR ?= /lib/modules/`uname -r`/build
>+KDIR ?= $(module_prefix)/lib/modules/`uname -r`/build
> KVER ?= `uname -r`
> ifeq ($(FAKE_BUILD),)
>     FAKE_BUILD=0
>diff --git a/testsuite/setup-rootfs.sh b/testsuite/setup-rootfs.sh
>index 4440ddcd6b4d..a780f9381b3c 100755
>--- a/testsuite/setup-rootfs.sh
>+++ b/testsuite/setup-rootfs.sh
>@@ -16,6 +16,19 @@ create_rootfs() {
> 	cp -r "$ROOTFS_PRISTINE" "$ROOTFS"
> 	find "$ROOTFS" -type d -exec chmod +w {} \;
> 	find "$ROOTFS" -type f -name .gitignore -exec rm -f {} \;
>+	if [ "$MODULE_DIRECTORY" != "/lib/modules" ] ; then
>+		sed -i -e "s|/lib/modules|$MODULE_DIRECTORY|g" $(find "$ROOTFS" -name \*.txt -o -name \*.conf -o -name \*.dep)
>+		sed -i -e "s|$MODULE_DIRECTORY/external|/lib/modules/external|g" $(find "$ROOTFS" -name \*.txt -o -name \*.conf -o -name \*.dep)

why this second sed?

Lucas De Marchi

>+		for i in "$ROOTFS"/*/lib/modules/* "$ROOTFS"/*/*/lib/modules/* ; do
>+			version="$(basename $i)"
>+			[ $version != 'external' ] || continue
>+			mod="$(dirname $i)"
>+			lib="$(dirname $mod)"
>+			up="$(dirname $lib)$MODULE_DIRECTORY"
>+			mkdir -p "$up"
>+			mv "$i" "$up"
>+		done
>+	fi
>
> 	if [ "$SYSCONFDIR" != "/etc" ]; then
> 		find "$ROOTFS" -type d -name etc -printf "%h\n" | while read -r e; do
>@@ -32,57 +45,57 @@ feature_enabled() {
>
> declare -A map
> map=(
>-    ["test-depmod/search-order-simple/lib/modules/4.4.4/kernel/crypto/"]="mod-simple.ko"
>-    ["test-depmod/search-order-simple/lib/modules/4.4.4/updates/"]="mod-simple.ko"
>-    ["test-depmod/search-order-same-prefix/lib/modules/4.4.4/foo/"]="mod-simple.ko"
>-    ["test-depmod/search-order-same-prefix/lib/modules/4.4.4/foobar/"]="mod-simple.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-c.ko"]="mod-loop-c.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-d.ko"]="mod-loop-d.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-e.ko"]="mod-loop-e.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-f.ko"]="mod-loop-f.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-g.ko"]="mod-loop-g.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-h.ko"]="mod-loop-h.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-i.ko"]="mod-loop-i.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-j.ko"]="mod-loop-j.ko"
>-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-k.ko"]="mod-loop-k.ko"
>-    ["test-depmod/search-order-external-first/lib/modules/4.4.4/foo/"]="mod-simple.ko"
>-    ["test-depmod/search-order-external-first/lib/modules/4.4.4/foobar/"]="mod-simple.ko"
>+    ["test-depmod/search-order-simple$MODULE_DIRECTORY/4.4.4/kernel/crypto/"]="mod-simple.ko"
>+    ["test-depmod/search-order-simple$MODULE_DIRECTORY/4.4.4/updates/"]="mod-simple.ko"
>+    ["test-depmod/search-order-same-prefix$MODULE_DIRECTORY/4.4.4/foo/"]="mod-simple.ko"
>+    ["test-depmod/search-order-same-prefix$MODULE_DIRECTORY/4.4.4/foobar/"]="mod-simple.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-c.ko"]="mod-loop-c.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-d.ko"]="mod-loop-d.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-e.ko"]="mod-loop-e.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-f.ko"]="mod-loop-f.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-g.ko"]="mod-loop-g.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-h.ko"]="mod-loop-h.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-i.ko"]="mod-loop-i.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-j.ko"]="mod-loop-j.ko"
>+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-k.ko"]="mod-loop-k.ko"
>+    ["test-depmod/search-order-external-first$MODULE_DIRECTORY/4.4.4/foo/"]="mod-simple.ko"
>+    ["test-depmod/search-order-external-first$MODULE_DIRECTORY/4.4.4/foobar/"]="mod-simple.ko"
>     ["test-depmod/search-order-external-first/lib/modules/external/"]="mod-simple.ko"
>-    ["test-depmod/search-order-external-last/lib/modules/4.4.4/foo/"]="mod-simple.ko"
>-    ["test-depmod/search-order-external-last/lib/modules/4.4.4/foobar/"]="mod-simple.ko"
>+    ["test-depmod/search-order-external-last$MODULE_DIRECTORY/4.4.4/foo/"]="mod-simple.ko"
>+    ["test-depmod/search-order-external-last$MODULE_DIRECTORY/4.4.4/foobar/"]="mod-simple.ko"
>     ["test-depmod/search-order-external-last/lib/modules/external/"]="mod-simple.ko"
>-    ["test-depmod/search-order-override/lib/modules/4.4.4/foo/"]="mod-simple.ko"
>-    ["test-depmod/search-order-override/lib/modules/4.4.4/override/"]="mod-simple.ko"
>-    ["test-dependencies/lib/modules/4.0.20-kmod/kernel/fs/foo/"]="mod-foo-b.ko"
>-    ["test-dependencies/lib/modules/4.0.20-kmod/kernel/"]="mod-foo-c.ko"
>-    ["test-dependencies/lib/modules/4.0.20-kmod/kernel/lib/"]="mod-foo-a.ko"
>-    ["test-dependencies/lib/modules/4.0.20-kmod/kernel/fs/"]="mod-foo.ko"
>+    ["test-depmod/search-order-override$MODULE_DIRECTORY/4.4.4/foo/"]="mod-simple.ko"
>+    ["test-depmod/search-order-override$MODULE_DIRECTORY/4.4.4/override/"]="mod-simple.ko"
>+    ["test-dependencies$MODULE_DIRECTORY/4.0.20-kmod/kernel/fs/foo/"]="mod-foo-b.ko"
>+    ["test-dependencies$MODULE_DIRECTORY/4.0.20-kmod/kernel/"]="mod-foo-c.ko"
>+    ["test-dependencies$MODULE_DIRECTORY/4.0.20-kmod/kernel/lib/"]="mod-foo-a.ko"
>+    ["test-dependencies$MODULE_DIRECTORY/4.0.20-kmod/kernel/fs/"]="mod-foo.ko"
>     ["test-init/"]="mod-simple.ko"
>     ["test-remove/"]="mod-simple.ko"
>-    ["test-modprobe/show-depends/lib/modules/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
>-    ["test-modprobe/show-depends/lib/modules/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
>-    ["test-modprobe/show-depends/lib/modules/4.4.4/kernel/mod-simple.ko"]="mod-simple.ko"
>+    ["test-modprobe/show-depends$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
>+    ["test-modprobe/show-depends$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
>+    ["test-modprobe/show-depends$MODULE_DIRECTORY/4.4.4/kernel/mod-simple.ko"]="mod-simple.ko"
>     ["test-modprobe/show-exports/mod-loop-a.ko"]="mod-loop-a.ko"
>-    ["test-modprobe/softdep-loop/lib/modules/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
>-    ["test-modprobe/softdep-loop/lib/modules/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
>-    ["test-modprobe/install-cmd-loop/lib/modules/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
>-    ["test-modprobe/install-cmd-loop/lib/modules/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
>-    ["test-modprobe/force/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
>-    ["test-modprobe/oldkernel/lib/modules/3.3.3/kernel/"]="mod-simple.ko"
>-    ["test-modprobe/oldkernel-force/lib/modules/3.3.3/kernel/"]="mod-simple.ko"
>-    ["test-modprobe/alias-to-none/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
>-    ["test-modprobe/module-param-kcmdline/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
>+    ["test-modprobe/softdep-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
>+    ["test-modprobe/softdep-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
>+    ["test-modprobe/install-cmd-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
>+    ["test-modprobe/install-cmd-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
>+    ["test-modprobe/force$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
>+    ["test-modprobe/oldkernel$MODULE_DIRECTORY/3.3.3/kernel/"]="mod-simple.ko"
>+    ["test-modprobe/oldkernel-force$MODULE_DIRECTORY/3.3.3/kernel/"]="mod-simple.ko"
>+    ["test-modprobe/alias-to-none$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
>+    ["test-modprobe/module-param-kcmdline$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
>     ["test-modprobe/external/lib/modules/external/"]="mod-simple.ko"
>     ["test-modprobe/module-from-abspath/home/foo/"]="mod-simple.ko"
>     ["test-modprobe/module-from-relpath/home/foo/"]="mod-simple.ko"
>-    ["test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/block/cciss.ko"]="mod-fake-cciss.ko"
>-    ["test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/scsi/hpsa.ko"]="mod-fake-hpsa.ko"
>-    ["test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/scsi/scsi_mod.ko"]="mod-fake-scsi-mod.ko"
>-    ["test-depmod/modules-outdir/lib/modules/4.4.4/kernel/drivers/block/cciss.ko"]="mod-fake-cciss.ko"
>-    ["test-depmod/modules-outdir/lib/modules/4.4.4/kernel/drivers/scsi/hpsa.ko"]="mod-fake-hpsa.ko"
>-    ["test-depmod/modules-outdir/lib/modules/4.4.4/kernel/drivers/scsi/scsi_mod.ko"]="mod-fake-scsi-mod.ko"
>+    ["test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/block/cciss.ko"]="mod-fake-cciss.ko"
>+    ["test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/hpsa.ko"]="mod-fake-hpsa.ko"
>+    ["test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/scsi_mod.ko"]="mod-fake-scsi-mod.ko"
>+    ["test-depmod/modules-outdir$MODULE_DIRECTORY/4.4.4/kernel/drivers/block/cciss.ko"]="mod-fake-cciss.ko"
>+    ["test-depmod/modules-outdir$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/hpsa.ko"]="mod-fake-hpsa.ko"
>+    ["test-depmod/modules-outdir$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/scsi_mod.ko"]="mod-fake-scsi-mod.ko"
>     ["test-modinfo/mod-simple-i386.ko"]="mod-simple-i386.ko"
>     ["test-modinfo/mod-simple-x86_64.ko"]="mod-simple-x86_64.ko"
>     ["test-modinfo/mod-simple-sparc64.ko"]="mod-simple-sparc64.ko"
>@@ -90,20 +103,20 @@ map=(
>     ["test-modinfo/mod-simple-sha256.ko"]="mod-simple.ko"
>     ["test-modinfo/mod-simple-pkcs7.ko"]="mod-simple.ko"
>     ["test-modinfo/external/lib/modules/external/mod-simple.ko"]="mod-simple.ko"
>-    ["test-tools/insert/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
>-    ["test-tools/remove/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
>+    ["test-tools/insert$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
>+    ["test-tools/remove$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
> )
>
> gzip_array=(
>-    "test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/block/cciss.ko"
>+    "test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/block/cciss.ko"
>     )
>
> xz_array=(
>-    "test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/scsi/scsi_mod.ko"
>+    "test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/scsi_mod.ko"
>     )
>
> zstd_array=(
>-    "test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/scsi/hpsa.ko"
>+    "test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/hpsa.ko"
>     )
>
> attach_sha256_array=(
>diff --git a/testsuite/test-depmod.c b/testsuite/test-depmod.c
>index 93606947f18a..c96dbf0a62be 100644
>--- a/testsuite/test-depmod.c
>+++ b/testsuite/test-depmod.c
>@@ -27,7 +27,7 @@
>
> #define MODULES_UNAME "4.4.4"
> #define MODULES_ORDER_ROOTFS TESTSUITE_ROOTFS "test-depmod/modules-order-compressed"
>-#define MODULES_ORDER_LIB_MODULES MODULES_ORDER_ROOTFS "/lib/modules/" MODULES_UNAME
>+#define MODULES_ORDER_LIB_MODULES MODULES_ORDER_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
> static noreturn int depmod_modules_order_for_compressed(const struct test *t)
> {
> 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
>@@ -55,8 +55,8 @@ DEFINE_TEST(depmod_modules_order_for_compressed,
> 	});
>
> #define MODULES_OUTDIR_ROOTFS TESTSUITE_ROOTFS "test-depmod/modules-outdir"
>-#define MODULES_OUTDIR_LIB_MODULES_OUTPUT MODULES_OUTDIR_ROOTFS "/outdir/lib/modules/" MODULES_UNAME
>-#define MODULES_OUTDIR_LIB_MODULES_INPUT MODULES_OUTDIR_ROOTFS "/lib/modules/" MODULES_UNAME
>+#define MODULES_OUTDIR_LIB_MODULES_OUTPUT MODULES_OUTDIR_ROOTFS "/outdir" MODULE_DIRECTORY "/" MODULES_UNAME
>+#define MODULES_OUTDIR_LIB_MODULES_INPUT MODULES_OUTDIR_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
> static noreturn int depmod_modules_outdir(const struct test *t)
> {
> 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
>@@ -87,7 +87,7 @@ DEFINE_TEST(depmod_modules_outdir,
> 	});
>
> #define SEARCH_ORDER_SIMPLE_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-simple"
>-#define SEARCH_ORDER_SIMPLE_LIB_MODULES SEARCH_ORDER_SIMPLE_ROOTFS "/lib/modules/" MODULES_UNAME
>+#define SEARCH_ORDER_SIMPLE_LIB_MODULES SEARCH_ORDER_SIMPLE_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
> static noreturn int depmod_search_order_simple(const struct test *t)
> {
> 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
>@@ -114,7 +114,7 @@ DEFINE_TEST(depmod_search_order_simple,
> 	});
>
> #define SEARCH_ORDER_SAME_PREFIX_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-same-prefix"
>-#define SEARCH_ORDER_SAME_PREFIX_LIB_MODULES SEARCH_ORDER_SAME_PREFIX_ROOTFS "/lib/modules/" MODULES_UNAME
>+#define SEARCH_ORDER_SAME_PREFIX_LIB_MODULES SEARCH_ORDER_SAME_PREFIX_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
> static noreturn int depmod_search_order_same_prefix(const struct test *t)
> {
> 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
>@@ -164,7 +164,7 @@ DEFINE_TEST(depmod_detect_loop,
> 	});
>
> #define SEARCH_ORDER_EXTERNAL_FIRST_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-external-first"
>-#define SEARCH_ORDER_EXTERNAL_FIRST_LIB_MODULES SEARCH_ORDER_EXTERNAL_FIRST_ROOTFS "/lib/modules/" MODULES_UNAME
>+#define SEARCH_ORDER_EXTERNAL_FIRST_LIB_MODULES SEARCH_ORDER_EXTERNAL_FIRST_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
> static noreturn int depmod_search_order_external_first(const struct test *t)
> {
> 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
>@@ -191,7 +191,7 @@ DEFINE_TEST(depmod_search_order_external_first,
> 	});
>
> #define SEARCH_ORDER_EXTERNAL_LAST_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-external-last"
>-#define SEARCH_ORDER_EXTERNAL_LAST_LIB_MODULES SEARCH_ORDER_EXTERNAL_LAST_ROOTFS "/lib/modules/" MODULES_UNAME
>+#define SEARCH_ORDER_EXTERNAL_LAST_LIB_MODULES SEARCH_ORDER_EXTERNAL_LAST_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
> static noreturn int depmod_search_order_external_last(const struct test *t)
> {
> 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
>@@ -218,7 +218,7 @@ DEFINE_TEST(depmod_search_order_external_last,
> 	});
>
> #define SEARCH_ORDER_OVERRIDE_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-override"
>-#define SEARCH_ORDER_OVERRIDE_LIB_MODULES SEARCH_ORDER_OVERRIDE_ROOTFS "/lib/modules/" MODULES_UNAME
>+#define SEARCH_ORDER_OVERRIDE_LIB_MODULES SEARCH_ORDER_OVERRIDE_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
> static noreturn int depmod_search_order_override(const struct test *t)
> {
> 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
>diff --git a/testsuite/test-testsuite.c b/testsuite/test-testsuite.c
>index 56e73609f204..c77c4bbc04eb 100644
>--- a/testsuite/test-testsuite.c
>+++ b/testsuite/test-testsuite.c
>@@ -64,7 +64,7 @@ static int testsuite_rootfs_fopen(const struct test *t)
> 	char s[100];
> 	int n;
>
>-	fp = fopen("/lib/modules/a", "r");
>+	fp = fopen(MODULE_DIRECTORY "/a", "r");
> 	if (fp == NULL)
> 		return EXIT_FAILURE;;
>
>@@ -89,7 +89,7 @@ static int testsuite_rootfs_open(const struct test *t)
> 	char buf[100];
> 	int fd, done;
>
>-	fd = open("/lib/modules/a", O_RDONLY);
>+	fd = open(MODULE_DIRECTORY "/a", O_RDONLY);
> 	if (fd < 0)
> 		return EXIT_FAILURE;
>
>@@ -121,12 +121,12 @@ static int testsuite_rootfs_stat_access(const struct test *t)
> {
> 	struct stat st;
>
>-	if (access("/lib/modules/a", F_OK) < 0) {
>+	if (access(MODULE_DIRECTORY "/a", F_OK) < 0) {
> 		ERR("access failed: %m\n");
> 		return EXIT_FAILURE;
> 	}
>
>-	if (stat("/lib/modules/a", &st) < 0) {
>+	if (stat(MODULE_DIRECTORY "/a", &st) < 0) {
> 		ERR("stat failed: %m\n");
> 		return EXIT_FAILURE;
> 	}
>diff --git a/tools/depmod.c b/tools/depmod.c
>index 7e9339923809..22bc1d87c83e 100644
>--- a/tools/depmod.c
>+++ b/tools/depmod.c
>@@ -911,7 +911,7 @@ struct vertex;
> struct mod {
> 	struct kmod_module *kmod;
> 	char *path;
>-	const char *relpath; /* path relative to '$ROOT/lib/modules/$VER/' */
>+	const char *relpath; /* path relative to '$ROOT$MODULE_DIRECTORY/$VER/' */
> 	char *uncrelpath; /* same as relpath but ending in .ko */
> 	struct kmod_list *info_list;
> 	struct kmod_list *dep_sym_list;
>@@ -3024,11 +3024,11 @@ static int do_depmod(int argc, char *argv[])
> 	}
>
> 	cfg.dirnamelen = snprintf(cfg.dirname, PATH_MAX,
>-				  "%s/lib/modules/%s",
>+				  "%s" MODULE_DIRECTORY "/%s",
> 				  root ?: "", cfg.kversion);
>
> 	cfg.outdirnamelen = snprintf(cfg.outdirname, PATH_MAX,
>-				     "%s/lib/modules/%s",
>+				     "%s" MODULE_DIRECTORY "/%s",
> 				     out_root ?: (root ?: ""), cfg.kversion);
>
> 	if (optind == argc)
>diff --git a/tools/kmod.c b/tools/kmod.c
>index a684c1d24284..3a2589c67447 100644
>--- a/tools/kmod.c
>+++ b/tools/kmod.c
>@@ -115,6 +115,7 @@ static int kmod_config(int argc, char *argv[])
> 	unsigned i;
> 	printf("{\"prefix\":\"" PREFIX "\""
> 			",\"sysconfdir\":\"" SYSCONFDIR "\""
>+			",\"module_directory\":\"" MODULE_DIRECTORY "\""
> 			",\"module_signature\":["
> #ifdef ENABLE_OPENSSL
> 			"\"PKCS#7\","
>diff --git a/tools/modinfo.c b/tools/modinfo.c
>index d0aab200af4e..cacc32dc4c40 100644
>--- a/tools/modinfo.c
>+++ b/tools/modinfo.c
>@@ -367,7 +367,7 @@ static void help(void)
> 		"\t-m, --modname               Handle argument as module name instead of alias or filename\n"
> 		"\t-F, --field=FIELD           Print only provided FIELD\n"
> 		"\t-k, --set-version=VERSION   Use VERSION instead of `uname -r`\n"
>-		"\t-b, --basedir=DIR           Use DIR as filesystem root for /lib/modules\n"
>+		"\t-b, --basedir=DIR           Use DIR as filesystem root for " MODULE_DIRECTORY "\n"
> 		"\t-V, --version               Show version\n"
> 		"\t-h, --help                  Show this help\n",
> 		program_invocation_short_name);
>@@ -462,7 +462,7 @@ static int do_modinfo(int argc, char *argv[])
> 			}
> 			kversion = u.release;
> 		}
>-		snprintf(dirname_buf, sizeof(dirname_buf), "%s/lib/modules/%s",
>+		snprintf(dirname_buf, sizeof(dirname_buf), "%s" MODULE_DIRECTORY "/%s",
> 			 root, kversion);
> 		dirname = dirname_buf;
> 	}
>diff --git a/tools/modprobe.c b/tools/modprobe.c
>index e891028349a8..5306bef250da 100644
>--- a/tools/modprobe.c
>+++ b/tools/modprobe.c
>@@ -142,7 +142,7 @@ static void help(void)
> 		"\t-n, --show                  Same as --dry-run\n"
>
> 		"\t-C, --config=FILE           Use FILE instead of default search paths\n"
>-		"\t-d, --dirname=DIR           Use DIR as filesystem root for /lib/modules\n"
>+		"\t-d, --dirname=DIR           Use DIR as filesystem root for " MODULE_DIRECTORY "\n"
> 		"\t-S, --set-version=VERSION   Use VERSION instead of `uname -r`\n"
>
> 		"\t-s, --syslog                print to syslog, not stderr\n"
>@@ -999,7 +999,7 @@ static int do_modprobe(int argc, char **orig_argv)
> 			kversion = u.release;
> 		}
> 		snprintf(dirname_buf, sizeof(dirname_buf),
>-				"%s/lib/modules/%s", root,
>+				"%s" MODULE_DIRECTORY "/%s", root,
> 				kversion);
> 		dirname = dirname_buf;
> 	}
>diff --git a/tools/static-nodes.c b/tools/static-nodes.c
>index 8d2356da73f3..5ef3743e967b 100644
>--- a/tools/static-nodes.c
>+++ b/tools/static-nodes.c
>@@ -212,15 +212,15 @@ static int do_static_nodes(int argc, char *argv[])
> 		goto finish;
> 	}
>
>-	snprintf(modules, sizeof(modules), "/lib/modules/%s/modules.devname", kernel.release);
>+	snprintf(modules, sizeof(modules), MODULE_DIRECTORY "/%s/modules.devname", kernel.release);
> 	in = fopen(modules, "re");
> 	if (in == NULL) {
> 		if (errno == ENOENT) {
>-			fprintf(stderr, "Warning: /lib/modules/%s/modules.devname not found - ignoring\n",
>+			fprintf(stderr, "Warning: " MODULE_DIRECTORY "/%s/modules.devname not found - ignoring\n",
> 				kernel.release);
> 			ret = EXIT_SUCCESS;
> 		} else {
>-			fprintf(stderr, "Error: could not open /lib/modules/%s/modules.devname - %m\n",
>+			fprintf(stderr, "Error: could not open " MODULE_DIRECTORY "/%s/modules.devname - %m\n",
> 				kernel.release);
> 			ret = EXIT_FAILURE;
> 		}
>-- 
>2.41.0
>
Michal Suchánek July 18, 2023, 8:32 a.m. UTC | #3
Hello,

On Mon, Jul 17, 2023 at 05:12:59PM -0300, Lucas De Marchi wrote:
> On Mon, Jul 17, 2023 at 12:39:53PM +0200, Michal Suchanek wrote:
> > modprobe.d is now searched under ${prefix}/lib, add ${module_directory} to
> > specify the directory where to search for kernel modules.
> 
> I was failing to see the relation of modprobe.d with the module
> directory. Maybe reword this slightly?
> 
> Now that modprobe.d is searched under ${prefix}/lib, allow a complete
> transition to files only under ${prefix} by adding a ${module_directory}
> configuration. This specifies the directory where to search for kernel
> modules and should match the location where the kernel/distro installs
> them.
> 
> > 
> > With this distributions that do not want to ship files in /lib can also
> > move kernel modules to /usr while others can keep them in /lib.
> > 
> > Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> > ---
> > v4: Make the whole path configurable
> > ---
> > Makefile.am                          |   3 +-
> > configure.ac                         |   7 ++
> > libkmod/libkmod.c                    |   4 +-
> > man/Makefile.am                      |   1 +
> > man/depmod.d.xml                     |   6 +-
> > man/depmod.xml                       |   4 +-
> > man/modinfo.xml                      |   2 +-
> > man/modprobe.xml                     |   2 +-
> > man/modules.dep.xml                  |   6 +-
> > testsuite/module-playground/Makefile |   2 +-
> > testsuite/setup-rootfs.sh            | 109 +++++++++++++++------------
> > testsuite/test-depmod.c              |  16 ++--
> > testsuite/test-testsuite.c           |   8 +-
> > tools/depmod.c                       |   6 +-
> > tools/kmod.c                         |   1 +
> > tools/modinfo.c                      |   4 +-
> > tools/modprobe.c                     |   4 +-
> > tools/static-nodes.c                 |   6 +-
> > 18 files changed, 107 insertions(+), 84 deletions(-)
> > 
> > diff --git a/Makefile.am b/Makefile.am
> > index 7aa5bfa5638d..981574558c93 100644
> > --- a/Makefile.am
> > +++ b/Makefile.am
> > @@ -20,6 +20,7 @@ AM_CPPFLAGS = \
> > 	-I$(top_srcdir) \
> > 	-DSYSCONFDIR=\""$(sysconfdir)"\" \
> > 	-DPREFIX=\""$(prefix)"\" \
> > +	-DMODULE_DIRECTORY=\""$(module_directory)"\" \
> > 	${zlib_CFLAGS}
> > 
> > AM_CFLAGS = $(OUR_CFLAGS)
> > @@ -220,7 +221,7 @@ EXTRA_DIST += testsuite/setup-rootfs.sh
> > MODULE_PLAYGROUND = testsuite/module-playground
> > ROOTFS = testsuite/rootfs
> > ROOTFS_PRISTINE = $(top_srcdir)/testsuite/rootfs-pristine
> > -CREATE_ROOTFS = $(AM_V_GEN) $(top_srcdir)/testsuite/setup-rootfs.sh $(ROOTFS_PRISTINE) $(ROOTFS) $(MODULE_PLAYGROUND) $(top_builddir)/config.h $(sysconfdir)
> > +CREATE_ROOTFS = $(AM_V_GEN) MODULE_DIRECTORY=$(module_directory) $(top_srcdir)/testsuite/setup-rootfs.sh $(ROOTFS_PRISTINE) $(ROOTFS) $(MODULE_PLAYGROUND) $(top_builddir)/config.h $(sysconfdir)
> > 
> > build-module-playground:
> > 	$(AM_V_GEN)if test "$(top_srcdir)" != "$(top_builddir)"; then \
> > diff --git a/configure.ac b/configure.ac
> > index 6064dee77ae6..a195c8e6b554 100644
> > --- a/configure.ac
> > +++ b/configure.ac
> > @@ -84,6 +84,12 @@ AC_ARG_WITH([rootlibdir],
> >         [], [with_rootlibdir=$libdir])
> > AC_SUBST([rootlibdir], [$with_rootlibdir])
> > 
> > +# Ideally this would be $prefix/lib/modules but default to /lib/modules for compatibility with earlier versions
> > +AC_ARG_WITH([module_directory],
> > +        AS_HELP_STRING([--with-module-directory=DIR], [directory in which to look for kernel modules - typically '/lib/modules' or '${prefix}/lib/modules']),
> > +        [], [with_module_directory=/lib/modules])
> > +AC_SUBST([module_directory], [$with_module_directory])
> > +
> > AC_ARG_WITH([zstd],
> > 	AS_HELP_STRING([--with-zstd], [handle Zstandard-compressed modules @<:@default=disabled@:>@]),
> > 	[], [with_zstd=no])
> > @@ -304,6 +310,7 @@ AC_MSG_RESULT([
> > 	$PACKAGE $VERSION
> > 	=======
> > 
> > +	module_directory:	${module_directory}
> > 	prefix:			${prefix}
> > 	sysconfdir:		${sysconfdir}
> > 	libdir:			${libdir}
> > diff --git a/libkmod/libkmod.c b/libkmod/libkmod.c
> > index f3139c1cef97..d2ed8748c833 100644
> > --- a/libkmod/libkmod.c
> > +++ b/libkmod/libkmod.c
> > @@ -209,7 +209,7 @@ static int log_priority(const char *priority)
> > 	return 0;
> > }
> > 
> > -static const char *dirname_default_prefix = "/lib/modules";
> > +static const char *dirname_default_prefix = MODULE_DIRECTORY;
> > 
> > static char *get_kernel_release(const char *dirname)
> > {
> > @@ -231,7 +231,7 @@ static char *get_kernel_release(const char *dirname)
> > /**
> >  * kmod_new:
> >  * @dirname: what to consider as linux module's directory, if NULL
> > - *           defaults to /lib/modules/`uname -r`. If it's relative,
> > + *           defaults to ${module_prefix}/lib/modules/`uname -r`. If it's relative,
> >  *           it's treated as relative to the current working directory.
> >  *           Otherwise, give an absolute dirname.
> >  * @config_paths: ordered array of paths (directories or files) where
> > diff --git a/man/Makefile.am b/man/Makefile.am
> > index ad07c30bbd24..25c2cc6fdf13 100644
> > --- a/man/Makefile.am
> > +++ b/man/Makefile.am
> > @@ -22,6 +22,7 @@ CLEANFILES = $(dist_man_MANS)
> > 	else \
> > 		sed -e '/@PREFIX@/d' $< ; \
> > 	fi | \
> > +	sed -e 's|@MODULE_DIRECTORY@|$(module_directory)|g' | \
> > 	$(XSLT) \
> > 		-o $@ \
> > 		--nonet \
> > diff --git a/man/depmod.d.xml b/man/depmod.d.xml
> > index 431ebca6654b..676977c69a4f 100644
> > --- a/man/depmod.d.xml
> > +++ b/man/depmod.d.xml
> > @@ -70,7 +70,7 @@
> >         </term>
> >         <listitem>
> >           <para>
> > -            This allows you to specify the order in which /lib/modules
> > +            This allows you to specify the order in which @MODULE_DIRECTORY@
> >             (or other configured module location) subdirectories will
> >             be processed by <command>depmod</command>. Directories are
> >             listed in order, with the highest priority given to the
> > @@ -101,7 +101,7 @@
> >             <command>depmod</command> command. It is possible to
> >             specify one kernel or all kernels using the * wildcard.
> >             <replaceable>modulesubdirectory</replaceable> is the
> > -            name of the subdirectory under /lib/modules (or other
> > +            name of the subdirectory under @MODULE_DIRECTORY@ (or other
> >             module location) where the target module is installed.
> >           </para>
> >           <para>
> > @@ -110,7 +110,7 @@
> >             specifying the following command: "override kmod * extra".
> >             This will ensure that any matching module name installed
> >             under the <command>extra</command> subdirectory within
> > -            /lib/modules (or other module location) will take priority
> > +            @MODULE_DIRECTORY@ (or other module location) will take priority
> >             over any likenamed module already provided by the kernel.
> >           </para>
> >         </listitem>
> > diff --git a/man/depmod.xml b/man/depmod.xml
> > index 3b0097184fd7..fce2a4a67a89 100644
> > --- a/man/depmod.xml
> > +++ b/man/depmod.xml
> > @@ -80,7 +80,7 @@
> >     </para>
> >     <para> <command>depmod</command> creates a list of module dependencies by
> >       reading each module under
> > -      <filename>/lib/modules/</filename><replaceable>version</replaceable> and
> > +      <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable> and
> >       determining what symbols it exports and what symbols it needs.  By
> >       default, this list is written to <filename>modules.dep</filename>, and a
> >       binary hashed version named <filename>modules.dep.bin</filename>, in the
> > @@ -141,7 +141,7 @@
> >         <listitem>
> >           <para>
> >             If your modules are not currently in the (normal) directory
> > -            <filename>/lib/modules/</filename><replaceable>version</replaceable>,
> > +            <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable>,
> >             but in a staging area, you can specify a
> >             <replaceable>basedir</replaceable> which is prepended to the
> >             directory name.  This <replaceable>basedir</replaceable> is
> > diff --git a/man/modinfo.xml b/man/modinfo.xml
> > index 9fe0324a2527..b6c4d6045829 100644
> > --- a/man/modinfo.xml
> > +++ b/man/modinfo.xml
> > @@ -54,7 +54,7 @@
> >       <command>modinfo</command> extracts information from the Linux Kernel
> >       modules given on the command line.  If the module name is not a filename,
> >       then the
> > -      <filename>/lib/modules/</filename><replaceable>version</replaceable>
> > +      <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable>
> >       directory is searched, as is also done by
> >       <citerefentry><refentrytitle>modprobe</refentrytitle><manvolnum>8</manvolnum></citerefentry>
> >       when loading kernel modules.
> > diff --git a/man/modprobe.xml b/man/modprobe.xml
> > index 91f9e27997cd..4d1fd59c000b 100644
> > --- a/man/modprobe.xml
> > +++ b/man/modprobe.xml
> > @@ -78,7 +78,7 @@
> >       is no difference between _ and - in module names (automatic
> >       underscore conversion is performed).
> >       <command>modprobe</command> looks in the module directory
> > -      <filename>/lib/modules/`uname -r`</filename> for all
> > +      <filename>@MODULE_DIRECTORY@/`uname -r`</filename> for all
> >       the modules and other files, except for the optional
> >       configuration files in the
> >       <filename>/etc/modprobe.d</filename> directory
> > diff --git a/man/modules.dep.xml b/man/modules.dep.xml
> > index ed633694ec9e..8ef6d8b3536e 100644
> > --- a/man/modules.dep.xml
> > +++ b/man/modules.dep.xml
> > @@ -34,8 +34,8 @@
> >   </refnamediv>
> > 
> >   <refsynopsisdiv>
> > -    <para><filename>/lib/modules/modules.dep</filename></para>
> > -    <para><filename>/lib/modules/modules.dep.bin</filename></para>
> > +    <para><filename>@MODULE_DIRECTORY@/modules.dep</filename></para>
> > +    <para><filename>@MODULE_DIRECTORY@/modules.dep.bin</filename></para>
> >   </refsynopsisdiv>
> > 
> >   <refsect1><title>DESCRIPTION</title>
> > @@ -43,7 +43,7 @@
> >       <filename>modules.dep.bin</filename> is a binary file generated by
> >       <command>depmod</command> listing the dependencies for
> >       every module in the directories under
> > -      <filename>/lib/modules/</filename><replaceable>version</replaceable>.
> > +      <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable>.
> >       It is used by kmod tools such as <command>modprobe</command> and
> >       libkmod.
> >     </para>
> > diff --git a/testsuite/module-playground/Makefile b/testsuite/module-playground/Makefile
> > index e6045b0dd932..a7ab09bea2bf 100644
> > --- a/testsuite/module-playground/Makefile
> > +++ b/testsuite/module-playground/Makefile
> > @@ -47,7 +47,7 @@ endif
> > 
> > else
> > # normal makefile
> > -KDIR ?= /lib/modules/`uname -r`/build
> > +KDIR ?= $(module_prefix)/lib/modules/`uname -r`/build
> > KVER ?= `uname -r`
> > ifeq ($(FAKE_BUILD),)
> >     FAKE_BUILD=0
> > diff --git a/testsuite/setup-rootfs.sh b/testsuite/setup-rootfs.sh
> > index 4440ddcd6b4d..a780f9381b3c 100755
> > --- a/testsuite/setup-rootfs.sh
> > +++ b/testsuite/setup-rootfs.sh
> > @@ -16,6 +16,19 @@ create_rootfs() {
> > 	cp -r "$ROOTFS_PRISTINE" "$ROOTFS"
> > 	find "$ROOTFS" -type d -exec chmod +w {} \;
> > 	find "$ROOTFS" -type f -name .gitignore -exec rm -f {} \;
> > +	if [ "$MODULE_DIRECTORY" != "/lib/modules" ] ; then
> > +		sed -i -e "s|/lib/modules|$MODULE_DIRECTORY|g" $(find "$ROOTFS" -name \*.txt -o -name \*.conf -o -name \*.dep)
> > +		sed -i -e "s|$MODULE_DIRECTORY/external|/lib/modules/external|g" $(find "$ROOTFS" -name \*.txt -o -name \*.conf -o -name \*.dep)
> 
> why this second sed?

These are 'external' modules not part of a kernel, the absolute path is
used in modules.dep and reported in outputs.

Moving these breaks the tests, and is beside the point.

Thanks

Michal
Michal Suchánek July 18, 2023, 8:43 a.m. UTC | #4
Hello,

On Mon, Jul 17, 2023 at 09:28:30PM +0200, Jan Engelhardt wrote:
> 
> On Monday 2023-07-17 12:39, Michal Suchanek wrote:
> 
> >modprobe.d is now searched under ${prefix}/lib, add ${module_directory} to
> >specify the directory where to search for kernel modules.
> >
> >With this distributions that do not want to ship files in /lib can also
> >move kernel modules to /usr while others can keep them in /lib.
> 
> This patch breaks kernel builds/installation.
> 
>  * assume $distro has given me a kmod that has your submission included,
>    and such kmod was ./configure'd --with-module-directory=/usr/lib/modules
> 
> With such a kmod, the module installation of current and past kernels
> is not possible, in other words, ** bisecting kernels ** is broken:

It might be nice to provide backwads compatibility with earlier
configurations.

However, if it comes at the cost of making the implementation more
complex and future maintenance more difficult it might not be such a
great idea. So far I have not seen a proposal how to do it nicely.

You can use any of the number of workarounds that have been used for
installing kernels on usrmerged distributions up until now.

sed -i -e s,/lib/modules,/usr/lib/modules, Makefile scripts/depmod.sh is
one.

Failing depmod is not critical, you can fix it up after the fact once
the modules are deployed on the test system.

You can also build a differently configured kmod for the purpose and
pass it with DEPMOD= to the kernel build.

Thanks

Michal
Jan Engelhardt July 18, 2023, 9:41 a.m. UTC | #5
On Tuesday 2023-07-18 10:43, Michal Suchánek wrote:
>> >With this distributions that do not want to ship files in /lib can also
>> >move kernel modules to /usr while others can keep them in /lib.
>> 
>> This patch breaks kernel builds/installation / bisecting [when the
>> system has a kmod ./configure'd --with-module-directory=/usr/lib/modules]
>
>It might be nice to provide backwads compatibility with earlier
>configurations.
>
>However, if it comes at the cost of making the implementation more
>complex and future maintenance more difficult it might not be such a
>great idea. So far I have not seen a proposal how to do it nicely.



diff --git a/configure.ac b/configure.ac
index a195c8e..7fde927 100644
--- a/configure.ac
+++ b/configure.ac
@@ -84,11 +84,7 @@ AC_ARG_WITH([rootlibdir],
         [], [with_rootlibdir=$libdir])
 AC_SUBST([rootlibdir], [$with_rootlibdir])
 
-# Ideally this would be $prefix/lib/modules but default to /lib/modules for compatibility with earlier versions
-AC_ARG_WITH([module_directory],
-        AS_HELP_STRING([--with-module-directory=DIR], [directory in which to look for kernel modules - typically '/lib/modules' or '${prefix}/lib/modules']),
-        [], [with_module_directory=/lib/modules])
-AC_SUBST([module_directory], [$with_module_directory])
+AC_SUBST([module_directory], [/lib/modules])
 
 AC_ARG_WITH([zstd],
 	AS_HELP_STRING([--with-zstd], [handle Zstandard-compressed modules @<:@default=disabled@:>@]),
diff --git a/libkmod/libkmod-internal.h b/libkmod/libkmod-internal.h
index 4a4af58..e2f9c95 100644
--- a/libkmod/libkmod-internal.h
+++ b/libkmod/libkmod-internal.h
@@ -199,3 +199,5 @@ void kmod_module_signature_info_free(struct kmod_signature_info *sig_info) __att
 
 /* libkmod-builtin.c */
 ssize_t kmod_builtin_get_modinfo(struct kmod_ctx *ctx, const char *modname, char ***modinfo) __attribute__((nonnull(1, 2, 3)));
+
+extern const char *dirname_default_prefix;
diff --git a/libkmod/libkmod.c b/libkmod/libkmod.c
index d2ed874..b426cde 100644
--- a/libkmod/libkmod.c
+++ b/libkmod/libkmod.c
@@ -209,7 +209,7 @@ static int log_priority(const char *priority)
 	return 0;
 }
 
-static const char *dirname_default_prefix = MODULE_DIRECTORY;
+const char *dirname_default_prefix = MODULE_DIRECTORY;
 
 static char *get_kernel_release(const char *dirname)
 {
diff --git a/tools/depmod.c b/tools/depmod.c
index 22bc1d8..929060f 100644
--- a/tools/depmod.c
+++ b/tools/depmod.c
@@ -65,6 +65,7 @@ static const struct option cmdopts[] = {
 	{ "quick", no_argument, 0, 'A' },
 	{ "basedir", required_argument, 0, 'b' },
 	{ "outdir", required_argument, 0, 'o' },
+	{ "modulesdir", required_argument, 0, 'M' },
 	{ "config", required_argument, 0, 'C' },
 	{ "symvers", required_argument, 0, 'E' },
 	{ "filesyms", required_argument, 0, 'F' },
@@ -2943,6 +2944,9 @@ static int do_depmod(int argc, char *argv[])
 				free(out_root);
 			out_root = path_make_absolute_cwd(optarg);
 			break;
+		case 'M':
+			dirname_default_prefix = optarg;
+			break;
 		case 'C': {
 			size_t bytes = sizeof(char *) * (n_config_paths + 2);
 			void *tmp = realloc(config_paths, bytes);
Michal Suchánek July 18, 2023, 10:29 a.m. UTC | #6
On Tue, Jul 18, 2023 at 11:41:32AM +0200, Jan Engelhardt wrote:
> 
> On Tuesday 2023-07-18 10:43, Michal Suchánek wrote:
> >> >With this distributions that do not want to ship files in /lib can also
> >> >move kernel modules to /usr while others can keep them in /lib.
> >> 
> >> This patch breaks kernel builds/installation / bisecting [when the
> >> system has a kmod ./configure'd --with-module-directory=/usr/lib/modules]
> >
> >It might be nice to provide backwads compatibility with earlier
> >configurations.
> >
> >However, if it comes at the cost of making the implementation more
> >complex and future maintenance more difficult it might not be such a
> >great idea. So far I have not seen a proposal how to do it nicely.
> 
> 
> 
> diff --git a/configure.ac b/configure.ac
> index a195c8e..7fde927 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -84,11 +84,7 @@ AC_ARG_WITH([rootlibdir],
>          [], [with_rootlibdir=$libdir])
>  AC_SUBST([rootlibdir], [$with_rootlibdir])
>  
> -# Ideally this would be $prefix/lib/modules but default to /lib/modules for compatibility with earlier versions
> -AC_ARG_WITH([module_directory],
> -        AS_HELP_STRING([--with-module-directory=DIR], [directory in which to look for kernel modules - typically '/lib/modules' or '${prefix}/lib/modules']),
> -        [], [with_module_directory=/lib/modules])
> -AC_SUBST([module_directory], [$with_module_directory])
> +AC_SUBST([module_directory], [/lib/modules])
>  
>  AC_ARG_WITH([zstd],
>  	AS_HELP_STRING([--with-zstd], [handle Zstandard-compressed modules @<:@default=disabled@:>@]),
> diff --git a/libkmod/libkmod-internal.h b/libkmod/libkmod-internal.h
> index 4a4af58..e2f9c95 100644
> --- a/libkmod/libkmod-internal.h
> +++ b/libkmod/libkmod-internal.h
> @@ -199,3 +199,5 @@ void kmod_module_signature_info_free(struct kmod_signature_info *sig_info) __att
>  
>  /* libkmod-builtin.c */
>  ssize_t kmod_builtin_get_modinfo(struct kmod_ctx *ctx, const char *modname, char ***modinfo) __attribute__((nonnull(1, 2, 3)));
> +
> +extern const char *dirname_default_prefix;
> diff --git a/libkmod/libkmod.c b/libkmod/libkmod.c
> index d2ed874..b426cde 100644
> --- a/libkmod/libkmod.c
> +++ b/libkmod/libkmod.c
> @@ -209,7 +209,7 @@ static int log_priority(const char *priority)
>  	return 0;
>  }
>  
> -static const char *dirname_default_prefix = MODULE_DIRECTORY;
> +const char *dirname_default_prefix = MODULE_DIRECTORY;
>  
>  static char *get_kernel_release(const char *dirname)
>  {
> diff --git a/tools/depmod.c b/tools/depmod.c
> index 22bc1d8..929060f 100644
> --- a/tools/depmod.c
> +++ b/tools/depmod.c
> @@ -65,6 +65,7 @@ static const struct option cmdopts[] = {
>  	{ "quick", no_argument, 0, 'A' },
>  	{ "basedir", required_argument, 0, 'b' },
>  	{ "outdir", required_argument, 0, 'o' },
> +	{ "modulesdir", required_argument, 0, 'M' },
>  	{ "config", required_argument, 0, 'C' },
>  	{ "symvers", required_argument, 0, 'E' },
>  	{ "filesyms", required_argument, 0, 'F' },
> @@ -2943,6 +2944,9 @@ static int do_depmod(int argc, char *argv[])
>  				free(out_root);
>  			out_root = path_make_absolute_cwd(optarg);
>  			break;
> +		case 'M':
> +			dirname_default_prefix = optarg;
> +			break;
>  		case 'C': {
>  			size_t bytes = sizeof(char *) * (n_config_paths + 2);
>  			void *tmp = realloc(config_paths, bytes);

That breaks kmod for the usrmerged distributions, though.

It might be fine to provide an option to override the build-time
default. Still the build-time default has to match where the modules are
placed in the distribution for things to work correctly out of the box.

Note: it will work either way at the times the module directory can be
accessed through the lib -> usr/lib compatibility symlink. The default
needs to be correct for the cases when the symlink is not provided.

So you could do

make DEPMOD='depmod -M /lib/modules'

to build an old kernel but you could equally do

make DEPMOD='/path/to/special/depmod'

If you needed

make DEPMOD='depmod -M /usr/lib/modules'

to build an usrmerged kernel on usrmerged distribution then this whole
exercise is pointless. kmod cannot find the usrmerged modules then.

Thanks

Michal
Jan Engelhardt July 18, 2023, 12:17 p.m. UTC | #7
On Tuesday 2023-07-18 12:29, Michal Suchánek wrote:
>> -static const char *dirname_default_prefix = MODULE_DIRECTORY;
>> +const char *dirname_default_prefix = MODULE_DIRECTORY;
>>  
>> @@ -2943,6 +2944,9 @@ static int do_depmod(int argc, char *argv[])
>>  				free(out_root);
>>  			out_root = path_make_absolute_cwd(optarg);
>>  			break;
>> +		case 'M':
>> +			dirname_default_prefix = optarg;
>> +			break;
>>  		case 'C': {
>>  			size_t bytes = sizeof(char *) * (n_config_paths + 2);
>>  			void *tmp = realloc(config_paths, bytes);
>
>That breaks kmod for the usrmerged distributions, though.

Does it though?
The *distro* has /lib -> /usr/lib,
the *staging area* for installation does not.

>[...]
>Note: it will work either way at the times the module directory can be
>accessed through the lib -> usr/lib compatibility symlink. The default
>needs to be correct for the cases when the symlink is not provided.

>So you could do
>
>make DEPMOD='depmod -M /lib/modules'

That would be a workable situation.
Michal Suchánek July 18, 2023, 12:27 p.m. UTC | #8
On Tue, Jul 18, 2023 at 02:17:08PM +0200, Jan Engelhardt wrote:
> 
> On Tuesday 2023-07-18 12:29, Michal Suchánek wrote:
> >> -static const char *dirname_default_prefix = MODULE_DIRECTORY;
> >> +const char *dirname_default_prefix = MODULE_DIRECTORY;
> >>  
> >> @@ -2943,6 +2944,9 @@ static int do_depmod(int argc, char *argv[])
> >>  				free(out_root);
> >>  			out_root = path_make_absolute_cwd(optarg);
> >>  			break;
> >> +		case 'M':
> >> +			dirname_default_prefix = optarg;
> >> +			break;
> >>  		case 'C': {
> >>  			size_t bytes = sizeof(char *) * (n_config_paths + 2);
> >>  			void *tmp = realloc(config_paths, bytes);
> >
> >That breaks kmod for the usrmerged distributions, though.
> 
> Does it though?
> The *distro* has /lib -> /usr/lib,
> the *staging area* for installation does not.

Yes, currently the fully installed distribution has the symlink, at
least openSUSE does.

However, there is a goal to remove it eventually, and even now it is not
present at all times.

Thanks

Michal
Jan Engelhardt July 18, 2023, 12:42 p.m. UTC | #9
On Tuesday 2023-07-18 14:27, Michal Suchánek wrote:
>> >
>> >That breaks kmod for the usrmerged distributions, though.
>> 
>> Does it though?
>> The *distro* has /lib -> /usr/lib,
>> the *staging area* for installation does not.
>
>Yes, currently the fully installed distribution has the symlink, at
>least openSUSE does.
>
>However, there is a goal to remove it eventually, and even now it is not
>present at all times.

The ELF interpreter /lib/ld-linux.so.2 is hardcoded everywhere.

Making /lib a directory again and bindmounting/symlinking
all the ELF interpreters, that seems to entail a bit more work
than just leaving /lib as a symlink.
Michal Suchánek July 18, 2023, 1:45 p.m. UTC | #10
On Tue, Jul 18, 2023 at 02:42:42PM +0200, Jan Engelhardt wrote:
> 
> On Tuesday 2023-07-18 14:27, Michal Suchánek wrote:
> >> >
> >> >That breaks kmod for the usrmerged distributions, though.
> >> 
> >> Does it though?
> >> The *distro* has /lib -> /usr/lib,
> >> the *staging area* for installation does not.
> >
> >Yes, currently the fully installed distribution has the symlink, at
> >least openSUSE does.
> >
> >However, there is a goal to remove it eventually, and even now it is not
> >present at all times.
> 
> The ELF interpreter /lib/ld-linux.so.2 is hardcoded everywhere.

Sure, there are other problems.

I will leave that for others that are familiar with that part of the
system.

Thanks

Michal
diff mbox series

Patch

diff --git a/Makefile.am b/Makefile.am
index 7aa5bfa5638d..981574558c93 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -20,6 +20,7 @@  AM_CPPFLAGS = \
 	-I$(top_srcdir) \
 	-DSYSCONFDIR=\""$(sysconfdir)"\" \
 	-DPREFIX=\""$(prefix)"\" \
+	-DMODULE_DIRECTORY=\""$(module_directory)"\" \
 	${zlib_CFLAGS}
 
 AM_CFLAGS = $(OUR_CFLAGS)
@@ -220,7 +221,7 @@  EXTRA_DIST += testsuite/setup-rootfs.sh
 MODULE_PLAYGROUND = testsuite/module-playground
 ROOTFS = testsuite/rootfs
 ROOTFS_PRISTINE = $(top_srcdir)/testsuite/rootfs-pristine
-CREATE_ROOTFS = $(AM_V_GEN) $(top_srcdir)/testsuite/setup-rootfs.sh $(ROOTFS_PRISTINE) $(ROOTFS) $(MODULE_PLAYGROUND) $(top_builddir)/config.h $(sysconfdir)
+CREATE_ROOTFS = $(AM_V_GEN) MODULE_DIRECTORY=$(module_directory) $(top_srcdir)/testsuite/setup-rootfs.sh $(ROOTFS_PRISTINE) $(ROOTFS) $(MODULE_PLAYGROUND) $(top_builddir)/config.h $(sysconfdir)
 
 build-module-playground:
 	$(AM_V_GEN)if test "$(top_srcdir)" != "$(top_builddir)"; then \
diff --git a/configure.ac b/configure.ac
index 6064dee77ae6..a195c8e6b554 100644
--- a/configure.ac
+++ b/configure.ac
@@ -84,6 +84,12 @@  AC_ARG_WITH([rootlibdir],
         [], [with_rootlibdir=$libdir])
 AC_SUBST([rootlibdir], [$with_rootlibdir])
 
+# Ideally this would be $prefix/lib/modules but default to /lib/modules for compatibility with earlier versions
+AC_ARG_WITH([module_directory],
+        AS_HELP_STRING([--with-module-directory=DIR], [directory in which to look for kernel modules - typically '/lib/modules' or '${prefix}/lib/modules']),
+        [], [with_module_directory=/lib/modules])
+AC_SUBST([module_directory], [$with_module_directory])
+
 AC_ARG_WITH([zstd],
 	AS_HELP_STRING([--with-zstd], [handle Zstandard-compressed modules @<:@default=disabled@:>@]),
 	[], [with_zstd=no])
@@ -304,6 +310,7 @@  AC_MSG_RESULT([
 	$PACKAGE $VERSION
 	=======
 
+	module_directory:	${module_directory}
 	prefix:			${prefix}
 	sysconfdir:		${sysconfdir}
 	libdir:			${libdir}
diff --git a/libkmod/libkmod.c b/libkmod/libkmod.c
index f3139c1cef97..d2ed8748c833 100644
--- a/libkmod/libkmod.c
+++ b/libkmod/libkmod.c
@@ -209,7 +209,7 @@  static int log_priority(const char *priority)
 	return 0;
 }
 
-static const char *dirname_default_prefix = "/lib/modules";
+static const char *dirname_default_prefix = MODULE_DIRECTORY;
 
 static char *get_kernel_release(const char *dirname)
 {
@@ -231,7 +231,7 @@  static char *get_kernel_release(const char *dirname)
 /**
  * kmod_new:
  * @dirname: what to consider as linux module's directory, if NULL
- *           defaults to /lib/modules/`uname -r`. If it's relative,
+ *           defaults to ${module_prefix}/lib/modules/`uname -r`. If it's relative,
  *           it's treated as relative to the current working directory.
  *           Otherwise, give an absolute dirname.
  * @config_paths: ordered array of paths (directories or files) where
diff --git a/man/Makefile.am b/man/Makefile.am
index ad07c30bbd24..25c2cc6fdf13 100644
--- a/man/Makefile.am
+++ b/man/Makefile.am
@@ -22,6 +22,7 @@  CLEANFILES = $(dist_man_MANS)
 	else \
 		sed -e '/@PREFIX@/d' $< ; \
 	fi | \
+	sed -e 's|@MODULE_DIRECTORY@|$(module_directory)|g' | \
 	$(XSLT) \
 		-o $@ \
 		--nonet \
diff --git a/man/depmod.d.xml b/man/depmod.d.xml
index 431ebca6654b..676977c69a4f 100644
--- a/man/depmod.d.xml
+++ b/man/depmod.d.xml
@@ -70,7 +70,7 @@ 
         </term>
         <listitem>
           <para>
-            This allows you to specify the order in which /lib/modules
+            This allows you to specify the order in which @MODULE_DIRECTORY@
             (or other configured module location) subdirectories will
             be processed by <command>depmod</command>. Directories are
             listed in order, with the highest priority given to the
@@ -101,7 +101,7 @@ 
             <command>depmod</command> command. It is possible to
             specify one kernel or all kernels using the * wildcard.
             <replaceable>modulesubdirectory</replaceable> is the
-            name of the subdirectory under /lib/modules (or other
+            name of the subdirectory under @MODULE_DIRECTORY@ (or other
             module location) where the target module is installed.
           </para>
           <para>
@@ -110,7 +110,7 @@ 
             specifying the following command: "override kmod * extra".
             This will ensure that any matching module name installed
             under the <command>extra</command> subdirectory within
-            /lib/modules (or other module location) will take priority
+            @MODULE_DIRECTORY@ (or other module location) will take priority
             over any likenamed module already provided by the kernel.
           </para>
         </listitem>
diff --git a/man/depmod.xml b/man/depmod.xml
index 3b0097184fd7..fce2a4a67a89 100644
--- a/man/depmod.xml
+++ b/man/depmod.xml
@@ -80,7 +80,7 @@ 
     </para>
     <para> <command>depmod</command> creates a list of module dependencies by
       reading each module under
-      <filename>/lib/modules/</filename><replaceable>version</replaceable> and
+      <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable> and
       determining what symbols it exports and what symbols it needs.  By
       default, this list is written to <filename>modules.dep</filename>, and a
       binary hashed version named <filename>modules.dep.bin</filename>, in the
@@ -141,7 +141,7 @@ 
         <listitem>
           <para>
             If your modules are not currently in the (normal) directory
-            <filename>/lib/modules/</filename><replaceable>version</replaceable>,
+            <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable>,
             but in a staging area, you can specify a
             <replaceable>basedir</replaceable> which is prepended to the
             directory name.  This <replaceable>basedir</replaceable> is
diff --git a/man/modinfo.xml b/man/modinfo.xml
index 9fe0324a2527..b6c4d6045829 100644
--- a/man/modinfo.xml
+++ b/man/modinfo.xml
@@ -54,7 +54,7 @@ 
       <command>modinfo</command> extracts information from the Linux Kernel
       modules given on the command line.  If the module name is not a filename,
       then the
-      <filename>/lib/modules/</filename><replaceable>version</replaceable>
+      <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable>
       directory is searched, as is also done by
       <citerefentry><refentrytitle>modprobe</refentrytitle><manvolnum>8</manvolnum></citerefentry>
       when loading kernel modules.
diff --git a/man/modprobe.xml b/man/modprobe.xml
index 91f9e27997cd..4d1fd59c000b 100644
--- a/man/modprobe.xml
+++ b/man/modprobe.xml
@@ -78,7 +78,7 @@ 
       is no difference between _ and - in module names (automatic
       underscore conversion is performed).
       <command>modprobe</command> looks in the module directory
-      <filename>/lib/modules/`uname -r`</filename> for all
+      <filename>@MODULE_DIRECTORY@/`uname -r`</filename> for all
       the modules and other files, except for the optional
       configuration files in the
       <filename>/etc/modprobe.d</filename> directory
diff --git a/man/modules.dep.xml b/man/modules.dep.xml
index ed633694ec9e..8ef6d8b3536e 100644
--- a/man/modules.dep.xml
+++ b/man/modules.dep.xml
@@ -34,8 +34,8 @@ 
   </refnamediv>
 
   <refsynopsisdiv>
-    <para><filename>/lib/modules/modules.dep</filename></para>
-    <para><filename>/lib/modules/modules.dep.bin</filename></para>
+    <para><filename>@MODULE_DIRECTORY@/modules.dep</filename></para>
+    <para><filename>@MODULE_DIRECTORY@/modules.dep.bin</filename></para>
   </refsynopsisdiv>
 
   <refsect1><title>DESCRIPTION</title>
@@ -43,7 +43,7 @@ 
       <filename>modules.dep.bin</filename> is a binary file generated by
       <command>depmod</command> listing the dependencies for
       every module in the directories under
-      <filename>/lib/modules/</filename><replaceable>version</replaceable>.
+      <filename>@MODULE_DIRECTORY@/</filename><replaceable>version</replaceable>.
       It is used by kmod tools such as <command>modprobe</command> and
       libkmod.
     </para>
diff --git a/testsuite/module-playground/Makefile b/testsuite/module-playground/Makefile
index e6045b0dd932..a7ab09bea2bf 100644
--- a/testsuite/module-playground/Makefile
+++ b/testsuite/module-playground/Makefile
@@ -47,7 +47,7 @@  endif
 
 else
 # normal makefile
-KDIR ?= /lib/modules/`uname -r`/build
+KDIR ?= $(module_prefix)/lib/modules/`uname -r`/build
 KVER ?= `uname -r`
 ifeq ($(FAKE_BUILD),)
     FAKE_BUILD=0
diff --git a/testsuite/setup-rootfs.sh b/testsuite/setup-rootfs.sh
index 4440ddcd6b4d..a780f9381b3c 100755
--- a/testsuite/setup-rootfs.sh
+++ b/testsuite/setup-rootfs.sh
@@ -16,6 +16,19 @@  create_rootfs() {
 	cp -r "$ROOTFS_PRISTINE" "$ROOTFS"
 	find "$ROOTFS" -type d -exec chmod +w {} \;
 	find "$ROOTFS" -type f -name .gitignore -exec rm -f {} \;
+	if [ "$MODULE_DIRECTORY" != "/lib/modules" ] ; then
+		sed -i -e "s|/lib/modules|$MODULE_DIRECTORY|g" $(find "$ROOTFS" -name \*.txt -o -name \*.conf -o -name \*.dep)
+		sed -i -e "s|$MODULE_DIRECTORY/external|/lib/modules/external|g" $(find "$ROOTFS" -name \*.txt -o -name \*.conf -o -name \*.dep)
+		for i in "$ROOTFS"/*/lib/modules/* "$ROOTFS"/*/*/lib/modules/* ; do
+			version="$(basename $i)"
+			[ $version != 'external' ] || continue
+			mod="$(dirname $i)"
+			lib="$(dirname $mod)"
+			up="$(dirname $lib)$MODULE_DIRECTORY"
+			mkdir -p "$up"
+			mv "$i" "$up"
+		done
+	fi
 
 	if [ "$SYSCONFDIR" != "/etc" ]; then
 		find "$ROOTFS" -type d -name etc -printf "%h\n" | while read -r e; do
@@ -32,57 +45,57 @@  feature_enabled() {
 
 declare -A map
 map=(
-    ["test-depmod/search-order-simple/lib/modules/4.4.4/kernel/crypto/"]="mod-simple.ko"
-    ["test-depmod/search-order-simple/lib/modules/4.4.4/updates/"]="mod-simple.ko"
-    ["test-depmod/search-order-same-prefix/lib/modules/4.4.4/foo/"]="mod-simple.ko"
-    ["test-depmod/search-order-same-prefix/lib/modules/4.4.4/foobar/"]="mod-simple.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-c.ko"]="mod-loop-c.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-d.ko"]="mod-loop-d.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-e.ko"]="mod-loop-e.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-f.ko"]="mod-loop-f.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-g.ko"]="mod-loop-g.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-h.ko"]="mod-loop-h.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-i.ko"]="mod-loop-i.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-j.ko"]="mod-loop-j.ko"
-    ["test-depmod/detect-loop/lib/modules/4.4.4/kernel/mod-loop-k.ko"]="mod-loop-k.ko"
-    ["test-depmod/search-order-external-first/lib/modules/4.4.4/foo/"]="mod-simple.ko"
-    ["test-depmod/search-order-external-first/lib/modules/4.4.4/foobar/"]="mod-simple.ko"
+    ["test-depmod/search-order-simple$MODULE_DIRECTORY/4.4.4/kernel/crypto/"]="mod-simple.ko"
+    ["test-depmod/search-order-simple$MODULE_DIRECTORY/4.4.4/updates/"]="mod-simple.ko"
+    ["test-depmod/search-order-same-prefix$MODULE_DIRECTORY/4.4.4/foo/"]="mod-simple.ko"
+    ["test-depmod/search-order-same-prefix$MODULE_DIRECTORY/4.4.4/foobar/"]="mod-simple.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-c.ko"]="mod-loop-c.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-d.ko"]="mod-loop-d.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-e.ko"]="mod-loop-e.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-f.ko"]="mod-loop-f.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-g.ko"]="mod-loop-g.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-h.ko"]="mod-loop-h.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-i.ko"]="mod-loop-i.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-j.ko"]="mod-loop-j.ko"
+    ["test-depmod/detect-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-k.ko"]="mod-loop-k.ko"
+    ["test-depmod/search-order-external-first$MODULE_DIRECTORY/4.4.4/foo/"]="mod-simple.ko"
+    ["test-depmod/search-order-external-first$MODULE_DIRECTORY/4.4.4/foobar/"]="mod-simple.ko"
     ["test-depmod/search-order-external-first/lib/modules/external/"]="mod-simple.ko"
-    ["test-depmod/search-order-external-last/lib/modules/4.4.4/foo/"]="mod-simple.ko"
-    ["test-depmod/search-order-external-last/lib/modules/4.4.4/foobar/"]="mod-simple.ko"
+    ["test-depmod/search-order-external-last$MODULE_DIRECTORY/4.4.4/foo/"]="mod-simple.ko"
+    ["test-depmod/search-order-external-last$MODULE_DIRECTORY/4.4.4/foobar/"]="mod-simple.ko"
     ["test-depmod/search-order-external-last/lib/modules/external/"]="mod-simple.ko"
-    ["test-depmod/search-order-override/lib/modules/4.4.4/foo/"]="mod-simple.ko"
-    ["test-depmod/search-order-override/lib/modules/4.4.4/override/"]="mod-simple.ko"
-    ["test-dependencies/lib/modules/4.0.20-kmod/kernel/fs/foo/"]="mod-foo-b.ko"
-    ["test-dependencies/lib/modules/4.0.20-kmod/kernel/"]="mod-foo-c.ko"
-    ["test-dependencies/lib/modules/4.0.20-kmod/kernel/lib/"]="mod-foo-a.ko"
-    ["test-dependencies/lib/modules/4.0.20-kmod/kernel/fs/"]="mod-foo.ko"
+    ["test-depmod/search-order-override$MODULE_DIRECTORY/4.4.4/foo/"]="mod-simple.ko"
+    ["test-depmod/search-order-override$MODULE_DIRECTORY/4.4.4/override/"]="mod-simple.ko"
+    ["test-dependencies$MODULE_DIRECTORY/4.0.20-kmod/kernel/fs/foo/"]="mod-foo-b.ko"
+    ["test-dependencies$MODULE_DIRECTORY/4.0.20-kmod/kernel/"]="mod-foo-c.ko"
+    ["test-dependencies$MODULE_DIRECTORY/4.0.20-kmod/kernel/lib/"]="mod-foo-a.ko"
+    ["test-dependencies$MODULE_DIRECTORY/4.0.20-kmod/kernel/fs/"]="mod-foo.ko"
     ["test-init/"]="mod-simple.ko"
     ["test-remove/"]="mod-simple.ko"
-    ["test-modprobe/show-depends/lib/modules/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
-    ["test-modprobe/show-depends/lib/modules/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
-    ["test-modprobe/show-depends/lib/modules/4.4.4/kernel/mod-simple.ko"]="mod-simple.ko"
+    ["test-modprobe/show-depends$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
+    ["test-modprobe/show-depends$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
+    ["test-modprobe/show-depends$MODULE_DIRECTORY/4.4.4/kernel/mod-simple.ko"]="mod-simple.ko"
     ["test-modprobe/show-exports/mod-loop-a.ko"]="mod-loop-a.ko"
-    ["test-modprobe/softdep-loop/lib/modules/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
-    ["test-modprobe/softdep-loop/lib/modules/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
-    ["test-modprobe/install-cmd-loop/lib/modules/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
-    ["test-modprobe/install-cmd-loop/lib/modules/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
-    ["test-modprobe/force/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
-    ["test-modprobe/oldkernel/lib/modules/3.3.3/kernel/"]="mod-simple.ko"
-    ["test-modprobe/oldkernel-force/lib/modules/3.3.3/kernel/"]="mod-simple.ko"
-    ["test-modprobe/alias-to-none/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
-    ["test-modprobe/module-param-kcmdline/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
+    ["test-modprobe/softdep-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
+    ["test-modprobe/softdep-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
+    ["test-modprobe/install-cmd-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-a.ko"]="mod-loop-a.ko"
+    ["test-modprobe/install-cmd-loop$MODULE_DIRECTORY/4.4.4/kernel/mod-loop-b.ko"]="mod-loop-b.ko"
+    ["test-modprobe/force$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
+    ["test-modprobe/oldkernel$MODULE_DIRECTORY/3.3.3/kernel/"]="mod-simple.ko"
+    ["test-modprobe/oldkernel-force$MODULE_DIRECTORY/3.3.3/kernel/"]="mod-simple.ko"
+    ["test-modprobe/alias-to-none$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
+    ["test-modprobe/module-param-kcmdline$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
     ["test-modprobe/external/lib/modules/external/"]="mod-simple.ko"
     ["test-modprobe/module-from-abspath/home/foo/"]="mod-simple.ko"
     ["test-modprobe/module-from-relpath/home/foo/"]="mod-simple.ko"
-    ["test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/block/cciss.ko"]="mod-fake-cciss.ko"
-    ["test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/scsi/hpsa.ko"]="mod-fake-hpsa.ko"
-    ["test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/scsi/scsi_mod.ko"]="mod-fake-scsi-mod.ko"
-    ["test-depmod/modules-outdir/lib/modules/4.4.4/kernel/drivers/block/cciss.ko"]="mod-fake-cciss.ko"
-    ["test-depmod/modules-outdir/lib/modules/4.4.4/kernel/drivers/scsi/hpsa.ko"]="mod-fake-hpsa.ko"
-    ["test-depmod/modules-outdir/lib/modules/4.4.4/kernel/drivers/scsi/scsi_mod.ko"]="mod-fake-scsi-mod.ko"
+    ["test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/block/cciss.ko"]="mod-fake-cciss.ko"
+    ["test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/hpsa.ko"]="mod-fake-hpsa.ko"
+    ["test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/scsi_mod.ko"]="mod-fake-scsi-mod.ko"
+    ["test-depmod/modules-outdir$MODULE_DIRECTORY/4.4.4/kernel/drivers/block/cciss.ko"]="mod-fake-cciss.ko"
+    ["test-depmod/modules-outdir$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/hpsa.ko"]="mod-fake-hpsa.ko"
+    ["test-depmod/modules-outdir$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/scsi_mod.ko"]="mod-fake-scsi-mod.ko"
     ["test-modinfo/mod-simple-i386.ko"]="mod-simple-i386.ko"
     ["test-modinfo/mod-simple-x86_64.ko"]="mod-simple-x86_64.ko"
     ["test-modinfo/mod-simple-sparc64.ko"]="mod-simple-sparc64.ko"
@@ -90,20 +103,20 @@  map=(
     ["test-modinfo/mod-simple-sha256.ko"]="mod-simple.ko"
     ["test-modinfo/mod-simple-pkcs7.ko"]="mod-simple.ko"
     ["test-modinfo/external/lib/modules/external/mod-simple.ko"]="mod-simple.ko"
-    ["test-tools/insert/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
-    ["test-tools/remove/lib/modules/4.4.4/kernel/"]="mod-simple.ko"
+    ["test-tools/insert$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
+    ["test-tools/remove$MODULE_DIRECTORY/4.4.4/kernel/"]="mod-simple.ko"
 )
 
 gzip_array=(
-    "test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/block/cciss.ko"
+    "test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/block/cciss.ko"
     )
 
 xz_array=(
-    "test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/scsi/scsi_mod.ko"
+    "test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/scsi_mod.ko"
     )
 
 zstd_array=(
-    "test-depmod/modules-order-compressed/lib/modules/4.4.4/kernel/drivers/scsi/hpsa.ko"
+    "test-depmod/modules-order-compressed$MODULE_DIRECTORY/4.4.4/kernel/drivers/scsi/hpsa.ko"
     )
 
 attach_sha256_array=(
diff --git a/testsuite/test-depmod.c b/testsuite/test-depmod.c
index 93606947f18a..c96dbf0a62be 100644
--- a/testsuite/test-depmod.c
+++ b/testsuite/test-depmod.c
@@ -27,7 +27,7 @@ 
 
 #define MODULES_UNAME "4.4.4"
 #define MODULES_ORDER_ROOTFS TESTSUITE_ROOTFS "test-depmod/modules-order-compressed"
-#define MODULES_ORDER_LIB_MODULES MODULES_ORDER_ROOTFS "/lib/modules/" MODULES_UNAME
+#define MODULES_ORDER_LIB_MODULES MODULES_ORDER_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
 static noreturn int depmod_modules_order_for_compressed(const struct test *t)
 {
 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
@@ -55,8 +55,8 @@  DEFINE_TEST(depmod_modules_order_for_compressed,
 	});
 
 #define MODULES_OUTDIR_ROOTFS TESTSUITE_ROOTFS "test-depmod/modules-outdir"
-#define MODULES_OUTDIR_LIB_MODULES_OUTPUT MODULES_OUTDIR_ROOTFS "/outdir/lib/modules/" MODULES_UNAME
-#define MODULES_OUTDIR_LIB_MODULES_INPUT MODULES_OUTDIR_ROOTFS "/lib/modules/" MODULES_UNAME
+#define MODULES_OUTDIR_LIB_MODULES_OUTPUT MODULES_OUTDIR_ROOTFS "/outdir" MODULE_DIRECTORY "/" MODULES_UNAME
+#define MODULES_OUTDIR_LIB_MODULES_INPUT MODULES_OUTDIR_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
 static noreturn int depmod_modules_outdir(const struct test *t)
 {
 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
@@ -87,7 +87,7 @@  DEFINE_TEST(depmod_modules_outdir,
 	});
 
 #define SEARCH_ORDER_SIMPLE_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-simple"
-#define SEARCH_ORDER_SIMPLE_LIB_MODULES SEARCH_ORDER_SIMPLE_ROOTFS "/lib/modules/" MODULES_UNAME
+#define SEARCH_ORDER_SIMPLE_LIB_MODULES SEARCH_ORDER_SIMPLE_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
 static noreturn int depmod_search_order_simple(const struct test *t)
 {
 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
@@ -114,7 +114,7 @@  DEFINE_TEST(depmod_search_order_simple,
 	});
 
 #define SEARCH_ORDER_SAME_PREFIX_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-same-prefix"
-#define SEARCH_ORDER_SAME_PREFIX_LIB_MODULES SEARCH_ORDER_SAME_PREFIX_ROOTFS "/lib/modules/" MODULES_UNAME
+#define SEARCH_ORDER_SAME_PREFIX_LIB_MODULES SEARCH_ORDER_SAME_PREFIX_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
 static noreturn int depmod_search_order_same_prefix(const struct test *t)
 {
 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
@@ -164,7 +164,7 @@  DEFINE_TEST(depmod_detect_loop,
 	});
 
 #define SEARCH_ORDER_EXTERNAL_FIRST_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-external-first"
-#define SEARCH_ORDER_EXTERNAL_FIRST_LIB_MODULES SEARCH_ORDER_EXTERNAL_FIRST_ROOTFS "/lib/modules/" MODULES_UNAME
+#define SEARCH_ORDER_EXTERNAL_FIRST_LIB_MODULES SEARCH_ORDER_EXTERNAL_FIRST_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
 static noreturn int depmod_search_order_external_first(const struct test *t)
 {
 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
@@ -191,7 +191,7 @@  DEFINE_TEST(depmod_search_order_external_first,
 	});
 
 #define SEARCH_ORDER_EXTERNAL_LAST_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-external-last"
-#define SEARCH_ORDER_EXTERNAL_LAST_LIB_MODULES SEARCH_ORDER_EXTERNAL_LAST_ROOTFS "/lib/modules/" MODULES_UNAME
+#define SEARCH_ORDER_EXTERNAL_LAST_LIB_MODULES SEARCH_ORDER_EXTERNAL_LAST_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
 static noreturn int depmod_search_order_external_last(const struct test *t)
 {
 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
@@ -218,7 +218,7 @@  DEFINE_TEST(depmod_search_order_external_last,
 	});
 
 #define SEARCH_ORDER_OVERRIDE_ROOTFS TESTSUITE_ROOTFS "test-depmod/search-order-override"
-#define SEARCH_ORDER_OVERRIDE_LIB_MODULES SEARCH_ORDER_OVERRIDE_ROOTFS "/lib/modules/" MODULES_UNAME
+#define SEARCH_ORDER_OVERRIDE_LIB_MODULES SEARCH_ORDER_OVERRIDE_ROOTFS MODULE_DIRECTORY "/" MODULES_UNAME
 static noreturn int depmod_search_order_override(const struct test *t)
 {
 	const char *progname = ABS_TOP_BUILDDIR "/tools/depmod";
diff --git a/testsuite/test-testsuite.c b/testsuite/test-testsuite.c
index 56e73609f204..c77c4bbc04eb 100644
--- a/testsuite/test-testsuite.c
+++ b/testsuite/test-testsuite.c
@@ -64,7 +64,7 @@  static int testsuite_rootfs_fopen(const struct test *t)
 	char s[100];
 	int n;
 
-	fp = fopen("/lib/modules/a", "r");
+	fp = fopen(MODULE_DIRECTORY "/a", "r");
 	if (fp == NULL)
 		return EXIT_FAILURE;;
 
@@ -89,7 +89,7 @@  static int testsuite_rootfs_open(const struct test *t)
 	char buf[100];
 	int fd, done;
 
-	fd = open("/lib/modules/a", O_RDONLY);
+	fd = open(MODULE_DIRECTORY "/a", O_RDONLY);
 	if (fd < 0)
 		return EXIT_FAILURE;
 
@@ -121,12 +121,12 @@  static int testsuite_rootfs_stat_access(const struct test *t)
 {
 	struct stat st;
 
-	if (access("/lib/modules/a", F_OK) < 0) {
+	if (access(MODULE_DIRECTORY "/a", F_OK) < 0) {
 		ERR("access failed: %m\n");
 		return EXIT_FAILURE;
 	}
 
-	if (stat("/lib/modules/a", &st) < 0) {
+	if (stat(MODULE_DIRECTORY "/a", &st) < 0) {
 		ERR("stat failed: %m\n");
 		return EXIT_FAILURE;
 	}
diff --git a/tools/depmod.c b/tools/depmod.c
index 7e9339923809..22bc1d87c83e 100644
--- a/tools/depmod.c
+++ b/tools/depmod.c
@@ -911,7 +911,7 @@  struct vertex;
 struct mod {
 	struct kmod_module *kmod;
 	char *path;
-	const char *relpath; /* path relative to '$ROOT/lib/modules/$VER/' */
+	const char *relpath; /* path relative to '$ROOT$MODULE_DIRECTORY/$VER/' */
 	char *uncrelpath; /* same as relpath but ending in .ko */
 	struct kmod_list *info_list;
 	struct kmod_list *dep_sym_list;
@@ -3024,11 +3024,11 @@  static int do_depmod(int argc, char *argv[])
 	}
 
 	cfg.dirnamelen = snprintf(cfg.dirname, PATH_MAX,
-				  "%s/lib/modules/%s",
+				  "%s" MODULE_DIRECTORY "/%s",
 				  root ?: "", cfg.kversion);
 
 	cfg.outdirnamelen = snprintf(cfg.outdirname, PATH_MAX,
-				     "%s/lib/modules/%s",
+				     "%s" MODULE_DIRECTORY "/%s",
 				     out_root ?: (root ?: ""), cfg.kversion);
 
 	if (optind == argc)
diff --git a/tools/kmod.c b/tools/kmod.c
index a684c1d24284..3a2589c67447 100644
--- a/tools/kmod.c
+++ b/tools/kmod.c
@@ -115,6 +115,7 @@  static int kmod_config(int argc, char *argv[])
 	unsigned i;
 	printf("{\"prefix\":\"" PREFIX "\""
 			",\"sysconfdir\":\"" SYSCONFDIR "\""
+			",\"module_directory\":\"" MODULE_DIRECTORY "\""
 			",\"module_signature\":["
 #ifdef ENABLE_OPENSSL
 			"\"PKCS#7\","
diff --git a/tools/modinfo.c b/tools/modinfo.c
index d0aab200af4e..cacc32dc4c40 100644
--- a/tools/modinfo.c
+++ b/tools/modinfo.c
@@ -367,7 +367,7 @@  static void help(void)
 		"\t-m, --modname               Handle argument as module name instead of alias or filename\n"
 		"\t-F, --field=FIELD           Print only provided FIELD\n"
 		"\t-k, --set-version=VERSION   Use VERSION instead of `uname -r`\n"
-		"\t-b, --basedir=DIR           Use DIR as filesystem root for /lib/modules\n"
+		"\t-b, --basedir=DIR           Use DIR as filesystem root for " MODULE_DIRECTORY "\n"
 		"\t-V, --version               Show version\n"
 		"\t-h, --help                  Show this help\n",
 		program_invocation_short_name);
@@ -462,7 +462,7 @@  static int do_modinfo(int argc, char *argv[])
 			}
 			kversion = u.release;
 		}
-		snprintf(dirname_buf, sizeof(dirname_buf), "%s/lib/modules/%s",
+		snprintf(dirname_buf, sizeof(dirname_buf), "%s" MODULE_DIRECTORY "/%s",
 			 root, kversion);
 		dirname = dirname_buf;
 	}
diff --git a/tools/modprobe.c b/tools/modprobe.c
index e891028349a8..5306bef250da 100644
--- a/tools/modprobe.c
+++ b/tools/modprobe.c
@@ -142,7 +142,7 @@  static void help(void)
 		"\t-n, --show                  Same as --dry-run\n"
 
 		"\t-C, --config=FILE           Use FILE instead of default search paths\n"
-		"\t-d, --dirname=DIR           Use DIR as filesystem root for /lib/modules\n"
+		"\t-d, --dirname=DIR           Use DIR as filesystem root for " MODULE_DIRECTORY "\n"
 		"\t-S, --set-version=VERSION   Use VERSION instead of `uname -r`\n"
 
 		"\t-s, --syslog                print to syslog, not stderr\n"
@@ -999,7 +999,7 @@  static int do_modprobe(int argc, char **orig_argv)
 			kversion = u.release;
 		}
 		snprintf(dirname_buf, sizeof(dirname_buf),
-				"%s/lib/modules/%s", root,
+				"%s" MODULE_DIRECTORY "/%s", root,
 				kversion);
 		dirname = dirname_buf;
 	}
diff --git a/tools/static-nodes.c b/tools/static-nodes.c
index 8d2356da73f3..5ef3743e967b 100644
--- a/tools/static-nodes.c
+++ b/tools/static-nodes.c
@@ -212,15 +212,15 @@  static int do_static_nodes(int argc, char *argv[])
 		goto finish;
 	}
 
-	snprintf(modules, sizeof(modules), "/lib/modules/%s/modules.devname", kernel.release);
+	snprintf(modules, sizeof(modules), MODULE_DIRECTORY "/%s/modules.devname", kernel.release);
 	in = fopen(modules, "re");
 	if (in == NULL) {
 		if (errno == ENOENT) {
-			fprintf(stderr, "Warning: /lib/modules/%s/modules.devname not found - ignoring\n",
+			fprintf(stderr, "Warning: " MODULE_DIRECTORY "/%s/modules.devname not found - ignoring\n",
 				kernel.release);
 			ret = EXIT_SUCCESS;
 		} else {
-			fprintf(stderr, "Error: could not open /lib/modules/%s/modules.devname - %m\n",
+			fprintf(stderr, "Error: could not open " MODULE_DIRECTORY "/%s/modules.devname - %m\n",
 				kernel.release);
 			ret = EXIT_FAILURE;
 		}