From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f65.google.com ([74.125.82.65]:36179 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750957AbdJBKuW (ORCPT ); Mon, 2 Oct 2017 06:50:22 -0400 From: Jonas Gorski Subject: [PATCH] kbuild: allow making undefined symbols fatal for external modules Date: Mon, 2 Oct 2017 12:50:04 +0200 Message-Id: <20171002105004.32426-1-jonas.gorski@gmail.com> Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Masahiro Yamada , Michal Marek By passing appropriate values in KBUILD_EXTRA_SYMBOLS it is possible to make modpost be able to resolve all symbols for external modules, even between to other external modules. Because of this, it might be desirable to make unresolved symbols an error on external module builds as well, to catch missing exports there as well. So add a new flag KBUILD_MODPOST_ERROR which can be set to enable this behaviour. It has no effect on non external module builds. Signed-off-by: Jonas Gorski --- The main target is to allow distributions (like LEDE) that make use of kernel backports and other out of tree drivers to be able to catch errors like missing EXPORT_SYMBOLs in the kernel early. scripts/Makefile.modpost | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 16923ba4b5b1..29f787bf8c3a 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -34,6 +34,8 @@ # KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined # symbols in the final module linking stage +# KBUILD_MODPOST_ERROR can be set to error out in case of undefined +# symbols in the final module linking stage for external modules # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. # This is solely useful to speed up test compiles PHONY := _modpost @@ -49,6 +51,8 @@ ifneq ($(KBUILD_EXTMOD),) obj := $(KBUILD_EXTMOD) src := $(obj) +KBUILD_MODPOST_WARN = $(if $(KBUILD_MODPOST_ERROR),,1) + # Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \ $(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile) @@ -78,7 +82,7 @@ modpost = scripts/mod/modpost \ $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ $(if $(CONFIG_DEBUG_SECTION_MISMATCH),,-S) \ $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ - $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w) + $(if $(KBUILD_MODPOST_WARN),-w) MODPOST_OPT=$(subst -i,-n,$(filter -i,$(MAKEFLAGS))) -- 2.13.2