From 1328a1ae0e9048ff4b7f6b60c497db7a2799e1b1 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 --- 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 c80291319cb2..2a062ea130b5 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 9a6cfca4f4130444cb02536a4fdf7b6e285c713e 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 --- 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 733e044fff8b..4a9a2cec0a1b 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -437,8 +437,8 @@ $(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 @@ -478,7 +478,7 @@ 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 @@ -531,7 +531,7 @@ 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 = $(cmd_link_multi-link) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 2a062ea130b5..72a0aa627c56 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -50,7 +50,7 @@ archive_builtin() if [ -n "${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 3a166fc2d4ef7a6b7e440271ee6bd1799c066605 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 --- 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 72a0aa627c56..e7b7eee31538 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