Commit e8639b7e authored by Matthew Maurer's avatar Matthew Maurer Committed by Masahiro Yamada
Browse files

modpost: Allow extended modversions without basic MODVERSIONS 



If you know that your kernel modules will only ever be loaded by a newer
kernel, you can disable BASIC_MODVERSIONS to save space. This also
allows easy creation of test modules to see how tooling will respond to
modules that only have the new format.

Signed-off-by: default avatarMatthew Maurer <mmaurer@google.com>
Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
parent fc7d5e32

kernel/module/Kconfig

+15 −0
Original line number Diff line number Diff line
@@ -217,6 +217,21 @@ config EXTENDED_MODVERSIONS 
	  The most likely reason you would enable this is to enable Rust

	  support. If unsure, say N.



config BASIC_MODVERSIONS

	bool "Basic Module Versioning Support"

	depends on MODVERSIONS

	default y

	help

	  This enables basic MODVERSIONS support, allowing older tools or

	  kernels to potentially load modules.



	  Disabling this may cause older `modprobe` or `kmod` to be unable

	  to read MODVERSIONS information from built modules. With this

	  disabled, older kernels may treat this module as unversioned.



	  This is enabled by default when MODVERSIONS are enabled.

	  If unsure, say Y.



config MODULE_SRCVERSION_ALL

	bool "Source checksum for all modules"

	help

scripts/Makefile.modpost

+1 −0
Original line number Diff line number Diff line
@@ -43,6 +43,7 @@ MODPOST = $(objtree)/scripts/mod/modpost 
modpost-args =										\

	$(if $(CONFIG_MODULES),-M)							\

	$(if $(CONFIG_MODVERSIONS),-m)							\

	$(if $(CONFIG_BASIC_MODVERSIONS),-b)						\

	$(if $(CONFIG_EXTENDED_MODVERSIONS),-x)						\

	$(if $(CONFIG_MODULE_SRCVERSION_ALL),-a)					\

	$(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E)					\

scripts/mod/modpost.c

+7 −2
Original line number Diff line number Diff line
@@ -33,6 +33,8 @@ static bool module_enabled; 
static bool modversions;

/* Is CONFIG_MODULE_SRCVERSION_ALL set? */

static bool all_versions;

/* Is CONFIG_BASIC_MODVERSIONS set? */

static bool basic_modversions;

/* Is CONFIG_EXTENDED_MODVERSIONS set? */

static bool extended_modversions;

/* If we are modposting external module set to 1 */
@@ -1857,7 +1859,7 @@ static void add_versions(struct buffer *b, struct module *mod) 
{

	struct symbol *s;



	if (!modversions)

	if (!basic_modversions)

		return;



	buf_printf(b, "\n");
@@ -2177,7 +2179,7 @@ int main(int argc, char **argv) 
	LIST_HEAD(dump_lists);

	struct dump_list *dl, *dl2;



	while ((opt = getopt(argc, argv, "ei:MmnT:to:au:WwENd:x")) != -1) {

	while ((opt = getopt(argc, argv, "ei:MmnT:to:au:WwENd:xb")) != -1) {

		switch (opt) {

		case 'e':

			external_module = true;
@@ -2226,6 +2228,9 @@ int main(int argc, char **argv) 
		case 'd':

			missing_namespace_deps = optarg;

			break;

		case 'b':

			basic_modversions = true;

			break;

		case 'x':

			extended_modversions = true;

			break;