From 0d989ac2c90b5f51fe12102d3cddf54b959f2014 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 12 May 2021 15:52:01 +0900 Subject: kbuild: remove libelf checks from top Makefile I do not see a good reason why only the libelf development package must be so carefully checked. Kbuild generally does not check host tools or libraries. For example, x86_64 defconfig fails to build with no libssl development package installed. scripts/extract-cert.c:21:10: fatal error: openssl/bio.h: No such file or directory 21 | #include | ^~~~~~~~~~~~~~~ To solve the build error, you need to install libssl-dev or openssl-devel package, depending on your distribution. 'apt-file search', 'dnf provides', etc. is your frined to find a proper package to install. This commit removes all the libelf checks from the top Makefile. If libelf is missing, objtool will fail to build in a similar pattern: .../linux/tools/objtool/include/objtool/elf.h:10:10: fatal error: gelf.h: No such file or directory 10 | #include You need to install libelf-dev, libelf-devel, or elfutils-libelf-devel to proceed. Another remarkable change is, CONFIG_STACK_VALIDATION (without CONFIG_UNWINDER_ORC) previously continued to build with a warning, but now it will treat missing libelf as an error. This is just a one-time installation, so it should not hurt to break a build and make a user install the package. BTW, the traditional way to handle such checks is autotool, but according to [1], I do not expect the kernel build would have similar scripting like './configure' does. [1]: https://lore.kernel.org/lkml/CA+55aFzr2HTZVOuzpHYDwmtRJLsVzE-yqg2DHpHi_9ePsYp5ug@mail.gmail.com/ Signed-off-by: Masahiro Yamada Acked-by: Andrii Nakryiko --- scripts/Makefile.modfinal | 2 -- 1 file changed, 2 deletions(-) (limited to 'scripts/Makefile.modfinal') diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index dd87cea9fba7..bdee3babc5cf 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -39,12 +39,10 @@ prelink-ext := .lto # so let's now process the prelinked binary before we link the module. ifdef CONFIG_STACK_VALIDATION -ifneq ($(SKIP_STACK_VALIDATION),1) cmd_ld_ko_o += \ $(objtree)/tools/objtool/objtool $(objtool_args) \ $(@:.ko=$(prelink-ext).o); -endif # SKIP_STACK_VALIDATION endif # CONFIG_STACK_VALIDATION endif # CONFIG_LTO_CLANG -- cgit v1.2.3