From patchwork Wed Feb 3 21:20:33 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Al Viro X-Patchwork-Id: 8209141 Return-Path: X-Original-To: patchwork-linux-kbuild@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id AE0C89FB33 for ; Wed, 3 Feb 2016 21:23:57 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C850C20270 for ; Wed, 3 Feb 2016 21:23:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D26CE202F0 for ; Wed, 3 Feb 2016 21:23:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755548AbcBCVUr (ORCPT ); Wed, 3 Feb 2016 16:20:47 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:43430 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751075AbcBCVUq (ORCPT ); Wed, 3 Feb 2016 16:20:46 -0500 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.76 #1 (Red Hat Linux)) id 1aR4qz-0004Mo-12; Wed, 03 Feb 2016 21:20:45 +0000 From: Al Viro To: linux-arch@vger.kernel.org Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 01/13] [kbuild] handle exports in lib-y objects reliably Date: Wed, 3 Feb 2016 21:20:33 +0000 Message-Id: <1454534445-16759-1-git-send-email-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <20160203211953.GT17997@ZenIV.linux.org.uk> References: <20160203211953.GT17997@ZenIV.linux.org.uk> Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Spam-Status: No, score=-7.3 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Al Viro Collect the symbols exported by anything that goes into lib.a and add an empty object (lib-exports.o) with explicit undefs for each of those to obj-y. That allows to relax the rules regarding the use of exports in lib-* objects - right now an object with export can be in lib-* only if we are guaranteed that there always will be users in built-in parts of the tree, otherwise it needs to be in obj-*. As the result, we have an unholy mix of lib- and obj- in lib/Makefile and (especially) in arch/*/lib/Makefile. Moreover, a change in generic part of the kernel can lead to mysteriously missing exports on some configs. With this change we don't have to worry about that anymore. One side effect is that built-in.o now pulls everything with exports from the corresponding lib.a (if such exists). That's exactly what we want for linking vmlinux and fortunately it's almost the only thing built-in.o is used in. arch/ia64/hp/sim/boot/bootloader is the only exception and it's easy to get rid of now - just turn everything in arch/ia64/lib into lib-* and don't bother with arch/ia64/lib/built-in.o anymore. Signed-off-by: Al Viro Acked-by: Michal Marek --- arch/ia64/hp/sim/boot/Makefile | 2 +- arch/ia64/lib/Makefile | 8 +++----- scripts/Makefile.build | 20 ++++++++++++++++++++ 3 files changed, 24 insertions(+), 6 deletions(-) diff --git a/arch/ia64/hp/sim/boot/Makefile b/arch/ia64/hp/sim/boot/Makefile index 2e805e0..df6e996 100644 --- a/arch/ia64/hp/sim/boot/Makefile +++ b/arch/ia64/hp/sim/boot/Makefile @@ -33,5 +33,5 @@ $(obj)/vmlinux.bin: vmlinux FORCE LDFLAGS_bootloader = -static -T $(obj)/bootloader: $(src)/bootloader.lds $(obj)/bootloader.o $(obj)/boot_head.o $(obj)/fw-emu.o \ - lib/lib.a arch/ia64/lib/built-in.o arch/ia64/lib/lib.a FORCE + lib/lib.a arch/ia64/lib/lib.a FORCE $(call if_changed,ld) diff --git a/arch/ia64/lib/Makefile b/arch/ia64/lib/Makefile index 98771e2..1f3d387 100644 --- a/arch/ia64/lib/Makefile +++ b/arch/ia64/lib/Makefile @@ -2,17 +2,15 @@ # Makefile for ia64-specific library routines.. # -obj-y := io.o - -lib-y := __divsi3.o __udivsi3.o __modsi3.o __umodsi3.o \ +lib-y := io.o __divsi3.o __udivsi3.o __modsi3.o __umodsi3.o \ __divdi3.o __udivdi3.o __moddi3.o __umoddi3.o \ checksum.o clear_page.o csum_partial_copy.o \ clear_user.o strncpy_from_user.o strlen_user.o strnlen_user.o \ flush.o ip_fast_csum.o do_csum.o \ memset.o strlen.o xor.o -obj-$(CONFIG_ITANIUM) += copy_page.o copy_user.o memcpy.o -obj-$(CONFIG_MCKINLEY) += copy_page_mck.o memcpy_mck.o +lib-$(CONFIG_ITANIUM) += copy_page.o copy_user.o memcpy.o +lib-$(CONFIG_MCKINLEY) += copy_page_mck.o memcpy_mck.o lib-$(CONFIG_PERFMON) += carta_random.o AFLAGS___divdi3.o = diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 2c47f9c..d041013 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -81,6 +81,7 @@ endif ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),) lib-target := $(obj)/lib.a +obj-y += $(obj)/lib-ksyms.o endif ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),) @@ -363,6 +364,25 @@ $(lib-target): $(lib-y) FORCE $(call if_changed,link_l_target) targets += $(lib-target) + +dummy-object = $(obj)/__lib_exports.o +ksyms-lds = $(obj)/lib-ksyms.lds +ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX +ref_prefix = EXTERN(_ +else +ref_prefix = EXTERN( +endif + +quiet_cmd_export_list = EXPORTS $@ +cmd_export_list = $(OBJDUMP) -h $< | \ + sed -ne '/___ksymtab/{s/.*+/$(ref_prefix)/;s/ .*/)/;p}' >$(ksyms-lds);\ + rm -f $(dummy-object);\ + $(AR) rcs$(KBUILD_ARFLAGS) $(dummy-object);\ + $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\ + rm $(dummy-object) $(ksyms-lds) + +$(obj)/lib-ksyms.o: $(lib-target) FORCE + $(call if_changed,export_list) endif #