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| author | Nicholas Piggin <npiggin@gmail.com> | 2017-06-20 01:52:05 +1000 |
|---|---|---|
| committer | Masahiro Yamada <yamada.masahiro@socionext.com> | 2017-06-30 09:03:03 +0900 |
| commit | 3a166fc2d4ef7a6b7e440271ee6bd1799c066605 (patch) | |
| tree | f0c4ea695592ad123e22c85d649ec917796a6652 /scripts | |
| parent | 9a6cfca4f4130444cb02536a4fdf7b6e285c713e (diff) | |
| download | lwn-3a166fc2d4ef7a6b7e440271ee6bd1799c066605.tar.gz lwn-3a166fc2d4ef7a6b7e440271ee6bd1799c066605.zip | |
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 <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Diffstat (limited to 'scripts')
| -rwxr-xr-x | scripts/link-vmlinux.sh | 45 |
1 files changed, 36 insertions, 9 deletions
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 |