From 2b50f7ab63685cd247e32ad321f7338ed130d3d5 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 8 Mar 2019 18:13:39 +0900 Subject: [PATCH] kbuild: add workaround for Debian make-kpkg Since commit 3812b8c5c5d5 ("kbuild: make -r/-R effective in top Makefile for old Make versions"), make-kpkg is not working. make-kpkg directly includes the top Makefile of Linux kernel, and appends some debian_* targets. /usr/share/kernel-package/ruleset/kernel_version.mk: # Include the kernel makefile override dot-config := 1 include Makefile dot-config := 1 I did not know the kernel Makefile was used in that way, and it is hard to guarantee the behavior when the kernel Makefile is included by another Makefile from a different project. It looks like Debian Stretch stopped providing make-kpkg. Maybe it is obsolete and being replaced with 'make deb-pkg' etc. but still widely used. This commit adds a workaround; if the top Makefile is included by another Makefile, skip sub-make in order to make the main part visible. 'MAKEFLAGS += -rR' does not become effective for GNU Make < 4.0, but Debian/Ubuntu is already using newer versions. The effect of this commit: Debian 8 (Jessie) : Fixed Debian 9 (Stretch) : make-kpkg (kernel-package) is not provided Ubuntu 14.04 LTS : NOT Fixed Ubuntu 16.04 LTS : Fixed Ubuntu 18.04 LTS : Fixed This commit cannot fix Ubuntu 14.04 because it installs GNU Make 3.81, but its support will end in Apr 2019, which is before the Linux v5.1 release. I added warning so that nobody would try to include the top Makefile. Fixes: 3812b8c5c5d5 ("kbuild: make -r/-R effective in top Makefile for old Make versions") Reported-by: Liz Zhang Signed-off-by: Masahiro Yamada Tested-by: Lili Deng Cc: Manoj Srivastava --- Makefile | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/Makefile b/Makefile index 9ef547fc7ffe..1ef92d705984 100644 --- a/Makefile +++ b/Makefile @@ -31,6 +31,16 @@ _all: # descending is started. They are now explicitly listed as the # prepare rule. +# Ugly workaround for Debian make-kpkg: +# make-kpkg directly includes the top Makefile of Linux kernel. In such a case, +# skip sub-make to support debian_* targets in ruleset/kernel_version.mk, but +# displays warning to discourage such abusage. +ifneq ($(word 2, $(MAKEFILE_LIST)),) +$(warning Do not include top Makefile of Linux Kernel) +sub-make-done := 1 +MAKEFLAGS += -rR +endif + ifneq ($(sub-make-done),1) # Do not use make's built-in rules and variables