[PATCH 4.9 121/128] kbuild: force to build vmlinux if CONFIG_MODVERSION=y

From: Greg Kroah-Hartman
Date: Fri Jun 19 2020 - 10:45:07 EST


From: Masahiro Yamada <masahiroy@xxxxxxxxxx>

commit 4b50c8c4eaf06a825d1c005c0b1b4a8307087b83 upstream.

This code does not work as stated in the comment.

$(CONFIG_MODVERSIONS) is always empty because it is expanded before
include/config/auto.conf is included. Hence, 'make modules' with
CONFIG_MODVERSION=y cannot record the version CRCs.

This has been broken since 2003, commit ("kbuild: Enable modules to be
build using the "make dir/" syntax"). [1]

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=15c6240cdc44bbeef3c4797ec860f9765ef4f1a7
Cc: linux-stable <stable@xxxxxxxxxxxxxxx> # v2.5.71+
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
Makefile | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

--- a/Makefile
+++ b/Makefile
@@ -313,12 +313,8 @@ KBUILD_MODULES :=
KBUILD_BUILTIN := 1

# If we have only "make modules", don't compile built-in objects.
-# When we're building modules with modversions, we need to consider
-# the built-in objects during the descend as well, in order to
-# make sure the checksums are up to date before we record them.
-
ifeq ($(MAKECMDGOALS),modules)
- KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
+ KBUILD_BUILTIN :=
endif

# If we have "make <whatever> modules", compile modules
@@ -1237,6 +1233,13 @@ ifdef CONFIG_MODULES

all: modules

+# When we're building modules with modversions, we need to consider
+# the built-in objects during the descend as well, in order to
+# make sure the checksums are up to date before we record them.
+ifdef CONFIG_MODVERSIONS
+ KBUILD_BUILTIN := 1
+endif
+
# Build modules
#
# A module can be listed more than once in obj-m resulting in