From 723ab99e48a70f537782f563495b965513f2f065 Mon Sep 17 00:00:00 2001 From: Stephen Rothwell Date: Wed, 24 Aug 2016 22:29:19 +1000 Subject: BACKPORT: kbuild: allow architectures to use thin archives instead of ld -r ld -r is an incremental link used to create built-in.o files in build subdirectories. It produces relocatable object files containing all its input files, and these are are then pulled together and relocated in the final link. Aside from the bloat, this constrains the final link relocations, which has bitten large powerpc builds with unresolvable relocations in the final link. Alan Modra has recommended the kernel use thin archives for linking. This is an alternative and means that the linker has more information available to it when it links the kernel. This patch enables a config option architectures can select, which causes all built-in.o files to be built as thin archives. built-in.o files in subdirectories do not get symbol table or index attached, which improves speed and size. The final link pass creates a built-in.o archive in the root output directory which includes the symbol table and index. The linker then uses takes this file to link. The --whole-archive linker option is required, because the linker now has visibility to every individual object file, and it will otherwise just completely avoid including those without external references (consider a file with EXPORT_SYMBOL or initcall or hardware exceptions as its only entry points). The traditional built works "by luck" as built-in.o files are large enough that they're going to get external references. However this optimisation is unpredictable for the kernel (due to above external references), ineffective at culling unused, and costly because the .o files have to be searched for references. Superior alternatives for link-time culling should be used instead. Build characteristics for inclink vs thinarc, on a small powerpc64le pseries VM with a modest .config: inclink thinarc sizes vmlinux 15 618 680 15 625 028 sum of all built-in.o 56 091 808 1 054 334 sum excluding root built-in.o 151 430 find -name built-in.o | xargs rm ; time make vmlinux real 22.772s 21.143s user 13.280s 13.430s sys 4.310s 2.750s - Final kernel pulled in only about 6K more, which shows how ineffective the object file culling is. - Build performance looks improved due to less pagecache activity. On IO constrained systems it could be a bigger win. - Build size saving is significant. Side note, the toochain understands archives, so there's some tricks, $ ar t built-in.o # list all files you linked with $ size built-in.o # and their sizes $ objdump -d built-in.o # disassembly (unrelocated) with filenames Implementation by sfr, minor tweaks by npiggin. Signed-off-by: Stephen Rothwell Signed-off-by: Nicholas Piggin Signed-off-by: Michal Marek (cherry-picked from a5967db9af51a84f5e181600954714a9e4c69f1f) Change-Id: I2569b083fc15ed8c423fc5c66d179055182e09c1 Signed-off-by: Dan Aloni Signed-off-by: Davide Garberi --- scripts/Makefile.build | 23 +++++++++++++--- scripts/link-vmlinux.sh | 71 +++++++++++++++++++++++++++++++++++++++++-------- 2 files changed, 79 insertions(+), 15 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 726d1b3f6759..e92e55e60d16 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -415,12 +415,22 @@ $(sort $(subdir-obj-y)): $(subdir-ym) ; # Rule to compile a set of .o files into one .o file # ifdef builtin-target -quiet_cmd_link_o_target = LD $@ + +ifdef CONFIG_THIN_ARCHIVES + cmd_make_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS) + cmd_make_empty_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS) + quiet_cmd_link_o_target = AR $@ +else + cmd_make_builtin = $(LD) $(ld_flags) -r -o + cmd_make_empty_builtin = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) + quiet_cmd_link_o_target = LD $@ +endif + # If the list of objects to link is empty, just create an empty built-in.o cmd_link_o_target = $(if $(strip $(obj-y)),\ - $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \ + $(cmd_make_builtin) $@ $(filter $(obj-y), $^) \ $(cmd_secanalysis),\ - rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@) + $(cmd_make_empty_builtin) $@) $(builtin-target): $(obj-y) FORCE $(call if_changed,link_o_target) @@ -446,7 +456,12 @@ $(modorder-target): $(subdir-ym) FORCE # ifdef lib-target quiet_cmd_link_l_target = AR $@ -cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y) + +ifdef CONFIG_THIN_ARCHIVES + cmd_link_l_target = rm -f $@; $(AR) rcsT$(KBUILD_ARFLAGS) $@ $(lib-y) +else + cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y) +endif $(lib-target): $(lib-y) FORCE $(call if_changed,link_l_target) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index ba6c34ea5429..270b663721a0 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -37,12 +37,40 @@ info() fi } +# Thin archive build here makes a final archive with +# symbol table and indexes from vmlinux objects, which can be +# used as input to linker. +# +# Traditional incremental style of link does not require this step +# +# built-in.o output file +# +archive_builtin() +{ + if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then + info AR built-in.o + rm -f built-in.o; + ${AR} rcsT${KBUILD_ARFLAGS} built-in.o \ + ${KBUILD_VMLINUX_INIT} \ + ${KBUILD_VMLINUX_MAIN} + fi +} + # Link of vmlinux.o used for section mismatch analysis # ${1} output file modpost_link() { - ${LD} ${LDFLAGS} -r -o ${1} ${KBUILD_VMLINUX_INIT} \ - --start-group ${KBUILD_VMLINUX_MAIN} --end-group + local objects + + if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then + objects="--whole-archive built-in.o" + else + objects="${KBUILD_VMLINUX_INIT} \ + --start-group \ + ${KBUILD_VMLINUX_MAIN} \ + --end-group" + fi + ${LD} ${LDFLAGS} -r -o ${1} ${objects} } # Link of vmlinux @@ -51,18 +79,36 @@ modpost_link() vmlinux_link() { local lds="${objtree}/${KBUILD_LDS}" + local objects if [ "${SRCARCH}" != "um" ]; then - ${LD} ${LDFLAGS} ${LDFLAGS_vmlinux} -o ${2} \ - -T ${lds} ${KBUILD_VMLINUX_INIT} \ - --start-group ${KBUILD_VMLINUX_MAIN} --end-group ${1} + if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then + objects="--whole-archive built-in.o ${1}" + else + objects="${KBUILD_VMLINUX_INIT} \ + --start-group \ + ${KBUILD_VMLINUX_MAIN} \ + --end-group \ + ${1}" + fi + + ${LD} ${LDFLAGS} ${LDFLAGS_vmlinux} -o ${2} \ + -T ${lds} ${objects} else - ${CC} ${CFLAGS_vmlinux} -o ${2} \ - -Wl,-T,${lds} ${KBUILD_VMLINUX_INIT} \ - -Wl,--start-group \ - ${KBUILD_VMLINUX_MAIN} \ - -Wl,--end-group \ - -lutil -lrt -lpthread ${1} + if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then + objects="-Wl,--whole-archive built-in.o ${1}" + else + objects="${KBUILD_VMLINUX_INIT} \ + -Wl,--start-group \ + ${KBUILD_VMLINUX_MAIN} \ + -Wl,--end-group \ + ${1}" + fi + + ${CC} ${CFLAGS_vmlinux} -o ${2} \ + -Wl,-T,${lds} \ + ${objects} \ + -lutil -lrt -lpthread rm -f linux fi } @@ -118,6 +164,7 @@ cleanup() rm -f .tmp_kallsyms* rm -f .tmp_version rm -f .tmp_vmlinux* + rm -f built-in.o rm -f System.map rm -f vmlinux rm -f vmlinux.o @@ -161,6 +208,8 @@ case "${KCONFIG_CONFIG}" in . "./${KCONFIG_CONFIG}" esac +archive_builtin + #link vmlinux.o info LD vmlinux.o modpost_link vmlinux.o -- cgit v1.2.3 From 3d01e1eba86b176412d8c962997f04e36dcb869c Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Fri, 17 Nov 2017 15:38:23 -0800 Subject: BACKPORT: FROMLIST: kbuild: add clang-version.sh Based on gcc-version.sh, clang-version.sh prints out the correct version of clang. Bug: 62093296 Bug: 67506682 Change-Id: I399ed4cfbe30f6ac93e519abd84dd4c7cb96e32c (am from https://patchwork.kernel.org/patch/10085763/) Tested-by: Nick Desaulniers Signed-off-by: Sami Tolvanen (cherry picked from commit b7ee59ba3390b5c5766abed375bc51b0fd66a2f3) Signed-off-by: Dan Aloni Signed-off-by: Davide Garberi --- scripts/clang-version.sh | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100755 scripts/clang-version.sh (limited to 'scripts') diff --git a/scripts/clang-version.sh b/scripts/clang-version.sh new file mode 100755 index 000000000000..9780efa56980 --- /dev/null +++ b/scripts/clang-version.sh @@ -0,0 +1,33 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# +# clang-version [-p] clang-command +# +# Prints the compiler version of `clang-command' in a canonical 4-digit form +# such as `0500' for clang-5.0 etc. +# +# With the -p option, prints the patchlevel as well, for example `050001' for +# clang-5.0.1 etc. +# + +if [ "$1" = "-p" ] ; then + with_patchlevel=1; + shift; +fi + +compiler="$*" + +if [ ${#compiler} -eq 0 ]; then + echo "Error: No compiler specified." + printf "Usage:\n\t$0 \n" + exit 1 +fi + +MAJOR=$(echo __clang_major__ | $compiler -E -x c - | tail -n 1) +MINOR=$(echo __clang_minor__ | $compiler -E -x c - | tail -n 1) +if [ "x$with_patchlevel" != "x" ] ; then + PATCHLEVEL=$(echo __clang_patchlevel__ | $compiler -E -x c - | tail -n 1) + printf "%02d%02d%02d\\n" $MAJOR $MINOR $PATCHLEVEL +else + printf "%02d%02d\\n" $MAJOR $MINOR +fi -- cgit v1.2.3 From eb0ad3ae07f9b74c3ee49eefb1506a44704690ad Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Fri, 17 Nov 2017 15:37:42 -0800 Subject: BACKPORT: kbuild: add __cc-ifversion and compiler-specific variants This change adds macros for testing both compiler name and version. Current cc-version, cc-ifversion etc. macros that test gcc version are left unchanged to prevent compatibility issues with existing tests. Bug: 62093296 Bug: 67506682 Change-Id: I14965fcc21dae8dfe31881b172214bf6f8a9f440 (am from https://patchwork.kernel.org/patch/10085767/) Signed-off-by: Sami Tolvanen Signed-off-by: Dan Aloni Signed-off-by: Davide Garberi --- scripts/Kbuild.include | 37 ++++++++++++++++++++++++++++++++++--- 1 file changed, 34 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 1112dd94b440..f955e3556942 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -148,6 +148,37 @@ cc-disable-warning = $(call try-run,\ # Expands to either gcc or clang cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc) +# __cc-version +# Returns compiler version +__cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/$(cc-name)-version.sh $(CC)) + +# __cc-fullversion +# Returns full compiler version +__cc-fullversion = $(shell $(CONFIG_SHELL) \ + $(srctree)/scripts/$(cc-name)-version.sh -p $(CC)) + +# __cc-ifversion +# Matches compiler name and version +# Usage: EXTRA_CFLAGS += $(call cc-if-name-version, gcc, -lt, 0402, -O1) +__cc-ifversion = $(shell [ $(cc-name) = $(1) ] && [ $(__cc-version) $(2) $(3) ] && echo $(4) || echo $(5)) + +# __cc-if-fullversion +# Matches compiler name and full version +# Usage: EXTRA_CFLAGS += $(call cc-if-name-fullversion, gcc, -lt, 040502, -O1) +__cc-if-fullversion = $(shell [ $(cc-name) = $(1) ] && [ $(__cc-fullversion) $(2) $(3) ] && echo $(4) || echo $(5)) + +# gcc-ifversion +gcc-ifversion = $(call __cc-ifversion, gcc, $(1), $(2), $(3), $(4)) + +# gcc-if-fullversion +gcc-if-fullversion = (call __cc-if-fullversion, gcc, $(1), $(2), $(3), $(4)) + +# clang-ifversion +clang-ifversion = $(call __cc-ifversion, clang, $(1), $(2), $(3), $(4)) + +# clang-if-fullversion +clang-if-fullversion = (call __cc-if-fullversion, clang, $(1), $(2), $(3), $(4)) + # cc-version cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) @@ -155,9 +186,9 @@ cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) cc-fullversion = $(shell $(CONFIG_SHELL) \ $(srctree)/scripts/gcc-version.sh -p $(CC)) -# cc-ifversion -# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) -cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4)) +# backward compatibility +cc-ifversion = $(gcc-ifversion) +cc-if-fullversion = $(gcc-if-fullversion) # cc-ldoption # Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) -- cgit v1.2.3 From 2d471de60bb497d8b3f9021ea255dcf1b8a07dc0 Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Wed, 25 Oct 2017 12:33:58 -0700 Subject: BACKPORT: kbuild: add ld-name macro GNU gold may require different flags than GNU ld. Add a macro for detecting the linker. Bug: 62093296 Bug: 67506682 Change-Id: I777f14bf4fd902de1f8dc73d7ecc3c0403eae5f5 (am from https://patchwork.kernel.org/patch/10085775/) Reviewed-by: Nick Desaulniers Signed-off-by: Sami Tolvanen (cherry picked from commit 552777bdc1d775bee1ffde43c23ab0b2c4501f35) Signed-off-by: Dan Aloni Signed-off-by: Davide Garberi --- scripts/Kbuild.include | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'scripts') diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index f955e3556942..5ad934a46ec9 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -204,6 +204,10 @@ ld-option = $(call try-run, $(LD) $(LDFLAGS) $(1) -v,$(1),$(2)) # Important: no spaces around options ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) +# ld-name +# Expands to either bfd or gold +ld-name = $(shell $(LD) -v 2>&1 | grep -q "GNU gold" && echo gold || echo bfd) + # ld-version # Note this is mainly for HJ Lu's 3 number binutil versions ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) -- cgit v1.2.3 From d2787c21f2b565c18395c6d84fa3604759d3b5a9 Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Fri, 17 Nov 2017 15:55:54 -0800 Subject: BACKPORT: kbuild: add __ld-ifversion and linker-specific macros Add macros for testing both linker name and version. Bug: 62093296 Bug: 67506682 Change-Id: Icbb13e9bb889017cd4a7457a62dea7e0335c53b5 (am from https://patchwork.kernel.org/patch/10085789/) Signed-off-by: Sami Tolvanen (cherry picked from commit 9403b68067aaa4941facfd260e14bb2b892073f5) Signed-off-by: Dan Aloni Signed-off-by: Davide Garberi --- scripts/Kbuild.include | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'scripts') diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 5ad934a46ec9..fcf10806de4d 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -216,6 +216,18 @@ ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) # Usage: $(call ld-ifversion, -ge, 22252, y) ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) +# __ld-ifversion +# Usage: $(call __ld-ifversion, gold, -ge, 112000000, y) +__ld-ifversion = $(shell [ $(ld-name) = $(1) ] && [ $(ld-version) $(2) $(3) ] && echo $(4) || echo $(5)) + +# bfd-ifversion +# Usage: $(call bfd-ifversion, -ge, 227000000, y) +bfd-ifversion = $(call __ld-ifversion, bfd, $(1), $(2), $(3), $(4)) + +# gold-ifversion +# Usage: $(call gold-ifversion, -ge, 112000000, y) +gold-ifversion = $(call __ld-ifversion, gold, $(1), $(2), $(3), $(4)) + ###### ### -- cgit v1.2.3 From 427d0fc67dc104ff2ecc95476409392bc53ce5c6 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Wed, 24 Aug 2016 22:29:21 +1000 Subject: BACKPORT: kbuild: add arch specific post-link Makefile Allow architectures to create arch/xxx/Makefile.postlink with targets for vmlinux, modules.ko, and clean, which will be invoked after final linking of vmlinux and modules. powerpc will use this to check vmlinux linker relocations for sanity, and may use it to fix up alternate instruction patch branch addresses. Signed-off-by: Nicholas Piggin Signed-off-by: Michal Marek (cherry picked from commit fbe6e37dab974dd0fc3660c001895f7bfd771c9a) Change-Id: Ic312087b1dc0e19797ea1bde54e61e84b300c45b Signed-off-by: Dan Aloni Signed-off-by: Davide Garberi --- scripts/Makefile.modpost | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 7718a64b1cd1..8cb7971b3f25 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -115,14 +115,18 @@ $(modules:.ko=.mod.o): %.mod.o: %.mod.c FORCE targets += $(modules:.ko=.mod.o) -# Step 6), final link of the modules +ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) + +# Step 6), final link of the modules with optional arch pass after final link quiet_cmd_ld_ko_o = LD [M] $@ - cmd_ld_ko_o = $(LD) -r $(LDFLAGS) \ - $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \ - -o $@ $(filter-out FORCE,$^) + cmd_ld_ko_o = \ + $(LD) -r $(LDFLAGS) \ + $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \ + -o $@ $(filter-out FORCE,$^) ; \ + $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) $(modules): %.ko :%.o %.mod.o FORCE - $(call if_changed,ld_ko_o) + +$(call if_changed,ld_ko_o) targets += $(modules) -- cgit v1.2.3 From c49d2545e437162d2a4b7f1e85f591c336129077 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Tue, 27 Oct 2015 14:02:24 +0100 Subject: BACKPORT: kbuild: Allow to specify composite modules with modname-m This allows to write drm-$(CONFIG_AGP) += drm_agpsupport.o without having to handle CONFIG_AGP=y vs. CONFIG_AGP=m. Only support this syntax for modules, since built-in code depending on something modular cannot work and init/Makefile actually relies on the current semantics. There are a few drivers which adapted to the current semantics out of necessity; these are fixed to also work when the respective subsystem is modular. Acked-by: Peter Chen [chipidea] Signed-off-by: Michal Marek Change-Id: Ibd0f7006c9d3b87f2b77e59bdc51c06cb361e9a0 (cherry picked from commit cf4f21938e13ea1533ebdcb21c46f1d998a44ee8) Signed-off-by: Dan Aloni Signed-off-by: Davide Garberi --- scripts/Makefile.build | 8 ++++++-- scripts/Makefile.lib | 4 ++-- 2 files changed, 8 insertions(+), 4 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index e92e55e60d16..d919fd613f4d 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -476,10 +476,14 @@ endif # -objs := # or # -y := +# or +# -m := +# The -m syntax only works if is a module link_multi_deps = \ $(filter $(addprefix $(obj)/, \ $($(subst $(obj)/,,$(@:.o=-objs))) \ -$($(subst $(obj)/,,$(@:.o=-y)))), $^) +$($(subst $(obj)/,,$(@:.o=-y))) \ +$($(subst $(obj)/,,$(@:.o=-m)))), $^) quiet_cmd_link_multi-y = LD $@ cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis) @@ -494,7 +498,7 @@ $(call multi_depend, $(multi-used-y), .o, -objs -y) $(multi-used-m): FORCE $(call if_changed,link_multi-m) @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod) -$(call multi_depend, $(multi-used-m), .o, -objs -y) +$(call multi_depend, $(multi-used-m), .o, -objs -y -m) targets += $(multi-used-y) $(multi-used-m) diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 5a93712ea570..2daf8d6e49a1 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -48,7 +48,7 @@ subdir-ym := $(sort $(subdir-y) $(subdir-m)) # if $(foo-objs) exists, foo.o is a composite object multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m)))) -multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m)))) +multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))), $(m)))) multi-used := $(multi-used-y) $(multi-used-m) single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m))) @@ -67,7 +67,7 @@ obj-dirs := $(dir $(multi-objs) $(obj-y)) # Replace multi-part objects by their individual parts, look at local dir only real-objs-y := $(foreach m, $(filter-out $(subdir-obj-y), $(obj-y)), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) $(extra-y) -real-objs-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) +real-objs-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)),$(m))) # Add subdir path -- cgit v1.2.3 From bf7540ffce4475591be8fb64f5db70c8311d37f1 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Thu, 21 Jan 2016 17:07:24 -0500 Subject: BACKPORT: kbuild: record needed exported symbols for modules Kernel modules are partially linked object files with some undefined symbols that are expected to be matched with EXPORT_SYMBOL() entries from elsewhere. Each .tmp_versions/*.mod file currently contains two line of text separated by a newline character. The first line has the actual module file name while the second line has a list of object files constituting that module. Those files are parsed by modpost (scripts/mod/sumversion.c), scripts/Makefile.modpost, scripts/Makefile.modsign, etc. Only the modpost utility cares about the second line while the others retrieve only the first line. Therefore we can add a third line to record the list of undefined symbols aka required EXPORT_SYMBOL() entries for each module into that file without breaking anything. Like for the second line, symbols are separated by a blank and the list is terminated with a newline character. To avoid needless build overhead, the undefined symbols extraction is performed only when CONFIG_TRIM_UNUSED_KSYMS is selected. Signed-off-by: Nicolas Pitre Acked-by: Rusty Russell Change-Id: Id8b7b497b8f4afce796a868fad99e9d3aee51e50 (cherry picked from commit 9895c03d48115c7783c0ef0a591447d53254ef84) Signed-off-by: Dan Aloni Signed-off-by: Davide Garberi --- scripts/Makefile.build | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index d919fd613f4d..1c9eca59c399 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -280,6 +280,13 @@ define rule_as_o_S mv -f $(dot-target).tmp $(dot-target).cmd endef +# List module undefined symbols (or empty line if not enabled) +ifdef CONFIG_TRIM_UNUSED_KSYMS +cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo +else +cmd_undef_syms = echo +endif + # Built-in and composite module parts $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE $(call cmd,force_checksrc) @@ -290,7 +297,8 @@ $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE $(call cmd,force_checksrc) $(call if_changed_rule,cc_o_c) - @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod) + @{ echo $(@:.o=.ko); echo $@; \ + $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod) quiet_cmd_cc_lst_c = MKLST $@ cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \ @@ -497,7 +505,8 @@ $(call multi_depend, $(multi-used-y), .o, -objs -y) $(multi-used-m): FORCE $(call if_changed,link_multi-m) - @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod) + @{ echo $(@:.o=.ko); echo $(link_multi_deps); \ + $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod) $(call multi_depend, $(multi-used-m), .o, -objs -y -m) targets += $(multi-used-y) $(multi-used-m) -- cgit v1.2.3 From f33c1532bd61b5f3ba60778c91df8222d29cc547 Mon Sep 17 00:00:00 2001 From: Robin Jarry Date: Mon, 26 Feb 2018 19:41:47 +0100 Subject: kbuild: use HOSTLDFLAGS for single .c executables When compiling executables from a single .c file, the linker is also invoked. Pass the HOSTLDFLAGS like for other linker commands. Signed-off-by: Robin Jarry Cc: Josh Poimboeuf Cc: Ingo Molnar Signed-off-by: Masahiro Yamada Change-Id: I8332132775e7cc220eb7d1e20911223bca65e1e2 --- scripts/Makefile.host | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.host b/scripts/Makefile.host index 133edfae5b8a..a89a0c5d43b2 100644 --- a/scripts/Makefile.host +++ b/scripts/Makefile.host @@ -85,7 +85,7 @@ hostcxx_flags = -Wp,-MD,$(depfile) $(__hostcxx_flags) # Create executable from a single .c file # host-csingle -> Executable quiet_cmd_host-csingle = HOSTCC $@ - cmd_host-csingle = $(HOSTCC) $(hostc_flags) -o $@ $< \ + cmd_host-csingle = $(HOSTCC) $(hostc_flags) $(HOSTLDFLAGS) -o $@ $< \ $(HOST_LOADLIBES) $(HOSTLOADLIBES_$(@F)) $(host-csingle): $(obj)/%: $(src)/%.c FORCE $(call if_changed_dep,host-csingle) -- cgit v1.2.3 From a54bbb725ccb3663f7fc7a2bf8b9ef1c34263bdb Mon Sep 17 00:00:00 2001 From: Olof Johansson Date: Fri, 13 Jul 2018 08:30:33 -0700 Subject: arm64: build with baremetal linker target instead of Linux when available Not all toolchains have the baremetal elf targets, RedHat/Fedora ones in particular. So, probe for whether it's available and use the previous (linux) targets if it isn't. Reported-by: Laura Abbott Tested-by: Laura Abbott Acked-by: Masahiro Yamada Cc: Paul Kocialkowski Signed-off-by: Olof Johansson Signed-off-by: Will Deacon Change-Id: Icf5462a8318b347cf11559c1654886c48c7a62b5 --- scripts/Kbuild.include | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index fcf10806de4d..8a491e6b542c 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -196,8 +196,8 @@ cc-ldoption = $(call try-run,\ $(CC) $(1) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) # ld-option -# Usage: LDFLAGS += $(call ld-option, -X) -ld-option = $(call try-run, $(LD) $(LDFLAGS) $(1) -v,$(1),$(2)) +# Usage: LDFLAGS += $(call ld-option, -X, -Y) +ld-option = $(call try-run, $(LD) $(LDFLAGS) $(1) -v,$(1),$(2),$(3)) # ar-option # Usage: KBUILD_ARFLAGS := $(call ar-option,D) -- cgit v1.2.3 From 369119e5df4e48f1e737791e781da185b7810921 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 8 Jun 2022 13:18:39 -0700 Subject: cert host tools: Stop complaining about deprecated OpenSSL functions OpenSSL 3.0 deprecated the OpenSSL's ENGINE API. That is as may be, but the kernel build host tools still use it. Disable the warning about deprecated declarations until somebody who cares fixes it. Signed-off-by: Linus Torvalds Change-Id: I655a75665920983abc9c3b0d73abfcb34f41b610 --- scripts/extract-cert.c | 7 +++++++ scripts/sign-file.c | 7 +++++++ 2 files changed, 14 insertions(+) (limited to 'scripts') diff --git a/scripts/extract-cert.c b/scripts/extract-cert.c index b071bf476fea..dd1a4bd706a2 100644 --- a/scripts/extract-cert.c +++ b/scripts/extract-cert.c @@ -23,6 +23,13 @@ #include #include +/* + * OpenSSL 3.0 deprecates the OpenSSL's ENGINE API. + * + * Remove this if/when that API is no longer used + */ +#pragma GCC diagnostic ignored "-Wdeprecated-declarations" + #define PKEY_ID_PKCS7 2 static __attribute__((noreturn)) diff --git a/scripts/sign-file.c b/scripts/sign-file.c index 250a7a645033..b57ade78b24a 100755 --- a/scripts/sign-file.c +++ b/scripts/sign-file.c @@ -27,6 +27,13 @@ #include #include +/* + * OpenSSL 3.0 deprecates the OpenSSL's ENGINE API. + * + * Remove this if/when that API is no longer used + */ +#pragma GCC diagnostic ignored "-Wdeprecated-declarations" + /* * Use CMS if we have openssl-1.0.0 or newer available - otherwise we have to * assume that it's not available and its header file is missing and that we -- cgit v1.2.3 From aa04fc78256d4b166d942a89b5f2cd7e86eb96df Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 24 Nov 2016 03:41:43 +1100 Subject: kbuild: minor improvement for thin archives build The root built-in.o archive is currently generated before all object files are built for the final link, due to final build of init/ after version update. In practice it seems like it doesn't matter because the archive symbol table does not change, but it is more logical to create the final archive as the last step. Signed-off-by: Nicholas Piggin Signed-off-by: Michal Marek Change-Id: I8255d2e046dc2632d6875a5f9e59514a8e16bb65 --- scripts/link-vmlinux.sh | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'scripts') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 270b663721a0..ed6a0127f724 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -208,15 +208,6 @@ case "${KCONFIG_CONFIG}" in . "./${KCONFIG_CONFIG}" esac -archive_builtin - -#link vmlinux.o -info LD vmlinux.o -modpost_link vmlinux.o - -# modpost vmlinux.o to check for section mismatches -${MAKE} -f "${srctree}/scripts/Makefile.modpost" vmlinux.o - # Update version info GEN .version if [ ! -r .version ]; then @@ -230,6 +221,15 @@ fi; # final build of init/ ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init +archive_builtin + +#link vmlinux.o +info LD vmlinux.o +modpost_link vmlinux.o + +# modpost vmlinux.o to check for section mismatches +${MAKE} -f "${srctree}/scripts/Makefile.modpost" vmlinux.o + kallsymso="" kallsyms_vmlinux="" if [ -n "${CONFIG_KALLSYMS}" ]; then -- cgit v1.2.3 From 43076241b514e16fdbbdeebaf77ad62da38d109e Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 9 Jun 2017 15:24:13 +1000 Subject: kbuild: thin archives final link close --whole-archives option Close the --whole-archives option with --no-whole-archive. Some architectures end up including additional .o and files multiple times after this, and they get duplicate symbols when they are brought under the --whole-archives option. This matches more closely with the incremental final link. Signed-off-by: Nicholas Piggin Signed-off-by: Masahiro Yamada Change-Id: I6efef94b96f62802de5efe10a5e5171d8983ab49 --- scripts/link-vmlinux.sh | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index ed6a0127f724..43a74357cd90 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -63,7 +63,7 @@ modpost_link() local objects if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then - objects="--whole-archive built-in.o" + objects="--whole-archive built-in.o --no-whole-archive" else objects="${KBUILD_VMLINUX_INIT} \ --start-group \ @@ -83,7 +83,7 @@ vmlinux_link() if [ "${SRCARCH}" != "um" ]; then if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then - objects="--whole-archive built-in.o ${1}" + objects="--whole-archive built-in.o ${1} --no-whole-archive" else objects="${KBUILD_VMLINUX_INIT} \ --start-group \ @@ -96,7 +96,7 @@ vmlinux_link() -T ${lds} ${objects} else if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then - objects="-Wl,--whole-archive built-in.o ${1}" + objects="-Wl,--whole-archive built-in.o ${1} -Wl,--no-whole-archive" else objects="${KBUILD_VMLINUX_INIT} \ -Wl,--start-group \ -- cgit v1.2.3 From 362c7b73bac86e4396a8aba314703ac2e572d2f6 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 24 Nov 2016 03:41:38 +1100 Subject: kbuild: thin archives for multi-y targets THIN_ARCHIVES builds archives for built-in.o targets, have it build multi-y targets as archives as well. This saves another ~15% of the size of intermediate artifacts in the build tree. After this patch, the linker is only used in final link, and special cases like vdsos. Signed-off-by: Nicholas Piggin Signed-off-by: Michal Marek Change-Id: Ic42ae9917ec19215a63e99b1fca1bd6fd4592294 --- scripts/Makefile.build | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 1c9eca59c399..4c1aec9b8da3 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -493,11 +493,18 @@ $($(subst $(obj)/,,$(@:.o=-objs))) \ $($(subst $(obj)/,,$(@:.o=-y))) \ $($(subst $(obj)/,,$(@:.o=-m)))), $^) -quiet_cmd_link_multi-y = LD $@ -cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis) +cmd_link_multi-link = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis) + +ifdef CONFIG_THIN_ARCHIVES + quiet_cmd_link_multi-y = AR $@ + cmd_link_multi-y = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS) $@ $(link_multi_deps) +else + quiet_cmd_link_multi-y = LD $@ + cmd_link_multi-y = $(cmd_link_multi-link) +endif quiet_cmd_link_multi-m = LD [M] $@ -cmd_link_multi-m = $(cmd_link_multi-y) +cmd_link_multi-m = $(cmd_link_multi-link) $(multi-used-y): FORCE $(call if_changed,link_multi-y) -- cgit v1.2.3 From 65dc3fbd1593e3dd16f0533e6bbea2f969daad65 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 9 Jun 2017 15:24:14 +1000 Subject: kbuild: thin archives use P option to ar The P option makes ar do full path name matching and can prevent ar from discarding files with duplicate names in some cases of creating thin archives from thin archives. The sh architecture in particular loses some object files from its kernel/cpu/sh*/ directories without this option. This could be a bug in binutils ar, but the P option should not cause any negative effects so it is safe to use to work around this with. Signed-off-by: Nicholas Piggin Signed-off-by: Masahiro Yamada Change-Id: I24f247271cd6bf245da10362a0cbb204033791b4 --- scripts/Makefile.build | 8 ++++---- scripts/link-vmlinux.sh | 2 +- 2 files changed, 5 insertions(+), 5 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 4c1aec9b8da3..23d49459ee66 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -425,8 +425,8 @@ $(sort $(subdir-obj-y)): $(subdir-ym) ; ifdef builtin-target ifdef CONFIG_THIN_ARCHIVES - cmd_make_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS) - cmd_make_empty_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS) + cmd_make_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) + cmd_make_empty_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) quiet_cmd_link_o_target = AR $@ else cmd_make_builtin = $(LD) $(ld_flags) -r -o @@ -466,7 +466,7 @@ ifdef lib-target quiet_cmd_link_l_target = AR $@ ifdef CONFIG_THIN_ARCHIVES - cmd_link_l_target = rm -f $@; $(AR) rcsT$(KBUILD_ARFLAGS) $@ $(lib-y) + cmd_link_l_target = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(lib-y) else cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y) endif @@ -497,7 +497,7 @@ cmd_link_multi-link = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secana ifdef CONFIG_THIN_ARCHIVES quiet_cmd_link_multi-y = AR $@ - cmd_link_multi-y = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS) $@ $(link_multi_deps) + cmd_link_multi-y = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) $@ $(link_multi_deps) else quiet_cmd_link_multi-y = LD $@ cmd_link_multi-y = $(cmd_link_multi-link) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 43a74357cd90..9cc6e2cc7077 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -50,7 +50,7 @@ archive_builtin() if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then info AR built-in.o rm -f built-in.o; - ${AR} rcsT${KBUILD_ARFLAGS} built-in.o \ + ${AR} rcsTP${KBUILD_ARFLAGS} built-in.o \ ${KBUILD_VMLINUX_INIT} \ ${KBUILD_VMLINUX_MAIN} fi -- cgit v1.2.3 From 2d3ce4f7a366c50d2af5bdaf5a0088ec6bc50500 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Tue, 20 Jun 2017 01:52:05 +1000 Subject: kbuild: handle libs-y archives separately from built-in.o archives The thin archives build currently puts all lib.a and built-in.o files together and links them with --whole-archive. This works because thin archives can recursively refer to thin archives. However some architectures include libgcc.a, which may not be a thin archive, or it may not be constructed with the "P" option, in which case its contents do not get linked correctly. So don't pull .a libs into the root built-in.o archive. These libs should already have symbol tables and indexes built, so they can be direct linker inputs. Move them out of the --whole-archive option, which restore the conditional linking behaviour of lib.a to thin archives builds. Signed-off-by: Nicholas Piggin Signed-off-by: Masahiro Yamada Change-Id: I42d8c27102477c7a21f29f3f4e7c6f19691ddca6 --- scripts/link-vmlinux.sh | 45 ++++++++++++++++++++++++++++++++++++--------- 1 file changed, 36 insertions(+), 9 deletions(-) (limited to 'scripts') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 9cc6e2cc7077..0a08006d600a 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -3,9 +3,12 @@ # link vmlinux # # vmlinux is linked from the objects selected by $(KBUILD_VMLINUX_INIT) and -# $(KBUILD_VMLINUX_MAIN). Most are built-in.o files from top-level directories -# in the kernel tree, others are specified in arch/$(ARCH)/Makefile. -# Ordering when linking is important, and $(KBUILD_VMLINUX_INIT) must be first. +# $(KBUILD_VMLINUX_MAIN) and $(KBUILD_VMLINUX_LIBS). Most are built-in.o files +# from top-level directories in the kernel tree, others are specified in +# arch/$(ARCH)/Makefile. Ordering when linking is important, and +# $(KBUILD_VMLINUX_INIT) must be first. $(KBUILD_VMLINUX_LIBS) are archives +# which are linked conditionally (not within --whole-archive), and do not +# require symbol indexes added. # # vmlinux # ^ @@ -16,6 +19,9 @@ # +--< $(KBUILD_VMLINUX_MAIN) # | +--< drivers/built-in.o mm/built-in.o + more # | +# +--< $(KBUILD_VMLINUX_LIBS) +# | +--< lib/lib.a + more +# | # +-< ${kallsymso} (see description in KALLSYMS section) # # vmlinux version (uname -v) cannot be updated during normal @@ -37,9 +43,10 @@ info() fi } -# Thin archive build here makes a final archive with -# symbol table and indexes from vmlinux objects, which can be -# used as input to linker. +# Thin archive build here makes a final archive with symbol table and indexes +# from vmlinux objects INIT and MAIN, which can be used as input to linker. +# KBUILD_VMLINUX_LIBS archives should already have symbol table and indexes +# added. # # Traditional incremental style of link does not require this step # @@ -63,11 +70,17 @@ modpost_link() local objects if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then - objects="--whole-archive built-in.o --no-whole-archive" + objects="--whole-archive \ + built-in.o \ + --no-whole-archive \ + --start-group \ + ${KBUILD_VMLINUX_LIBS} \ + --end-group" else objects="${KBUILD_VMLINUX_INIT} \ --start-group \ ${KBUILD_VMLINUX_MAIN} \ + ${KBUILD_VMLINUX_LIBS} \ --end-group" fi ${LD} ${LDFLAGS} -r -o ${1} ${objects} @@ -83,11 +96,18 @@ vmlinux_link() if [ "${SRCARCH}" != "um" ]; then if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then - objects="--whole-archive built-in.o ${1} --no-whole-archive" + objects="--whole-archive \ + built-in.o \ + --no-whole-archive \ + --start-group \ + ${KBUILD_VMLINUX_LIBS} \ + --end-group \ + ${1}" else objects="${KBUILD_VMLINUX_INIT} \ --start-group \ ${KBUILD_VMLINUX_MAIN} \ + ${KBUILD_VMLINUX_LIBS} \ --end-group \ ${1}" fi @@ -96,11 +116,18 @@ vmlinux_link() -T ${lds} ${objects} else if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then - objects="-Wl,--whole-archive built-in.o ${1} -Wl,--no-whole-archive" + objects="-Wl,--whole-archive \ + built-in.o \ + -Wl,--no-whole-archive \ + -Wl,--start-group \ + ${KBUILD_VMLINUX_LIBS} \ + -Wl,--end-group \ + ${1}" else objects="${KBUILD_VMLINUX_INIT} \ -Wl,--start-group \ ${KBUILD_VMLINUX_MAIN} \ + ${KBUILD_VMLINUX_LIBS} \ -Wl,--end-group \ ${1}" fi -- cgit v1.2.3