mirror of
https://github.com/torvalds/linux.git
synced 2024-11-27 06:31:52 +00:00
3473f26592
The Sourcery CodeBench Lite 2014.05 toolchain (gcc 4.8.3, binutils
2.24.51) has a GCC which implements -fuse-ld, and it doesn't include
the gold linker, but it lacks an ld.bfd executable in its
installation. This means that passing -fuse-ld=bfd fails with:
VDSO arch/arm/vdso/vdso.so.raw
collect2: fatal error: cannot find 'ld'
Arguably this is a deficiency in the toolchain, but I suspect it's
commonly used enough that it's worth accommodating: just use
cc-ldoption (to cause a link attempt) instead of cc-option to test
whether we can use -fuse-ld. So -fuse-ld=bfd won't be used with this
toolchain, but the build will rightly succeed, just as it does for
toolchains which don't implement -fuse-ld (and don't use gold as the
default linker).
Note: this will change the failure mode for a corner case I was trying
to handle in d2b30cd4b7, where the toolchain defaults to the gold
linker and the BFD linker is not found in PATH, from:
VDSO arch/arm/vdso/vdso.so.raw
collect2: fatal error: cannot find 'ld'
i.e. the BFD linker is not found, to:
OBJCOPY arch/arm/vdso/vdso.so
BFD: arch/arm/vdso/vdso.so: Not enough room for program headers, try
linking with -N
that is, we fail to prevent gold from being used as the linker, and it
produces an object that objcopy can't digest.
Reported-by: Baruch Siach <baruch@tkos.co.il>
Tested-by: Baruch Siach <baruch@tkos.co.il>
Tested-by: Raphaël Poggi <poggi.raph@gmail.com>
Fixes: d2b30cd4b7 ("ARM: 8384/1: VDSO: force use of BFD linker")
Cc: stable@vger.kernel.org
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
79 lines
2.3 KiB
Makefile
79 lines
2.3 KiB
Makefile
hostprogs-y := vdsomunge
|
|
|
|
obj-vdso := vgettimeofday.o datapage.o
|
|
|
|
# Build rules
|
|
targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.so.raw vdso.lds
|
|
obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
|
|
|
|
ccflags-y := -fPIC -fno-common -fno-builtin -fno-stack-protector
|
|
ccflags-y += -DDISABLE_BRANCH_PROFILING
|
|
|
|
VDSO_LDFLAGS := -Wl,-Bsymbolic -Wl,--no-undefined -Wl,-soname=linux-vdso.so.1
|
|
VDSO_LDFLAGS += -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096
|
|
VDSO_LDFLAGS += -nostdlib -shared
|
|
VDSO_LDFLAGS += $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
|
|
VDSO_LDFLAGS += $(call cc-ldoption, -Wl$(comma)--build-id)
|
|
VDSO_LDFLAGS += $(call cc-ldoption, -fuse-ld=bfd)
|
|
|
|
obj-$(CONFIG_VDSO) += vdso.o
|
|
extra-$(CONFIG_VDSO) += vdso.lds
|
|
CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
|
|
|
|
CFLAGS_REMOVE_vdso.o = -pg
|
|
|
|
# Force -O2 to avoid libgcc dependencies
|
|
CFLAGS_REMOVE_vgettimeofday.o = -pg -Os
|
|
CFLAGS_vgettimeofday.o = -O2
|
|
|
|
# Disable gcov profiling for VDSO code
|
|
GCOV_PROFILE := n
|
|
|
|
# Force dependency
|
|
$(obj)/vdso.o : $(obj)/vdso.so
|
|
|
|
# Link rule for the .so file
|
|
$(obj)/vdso.so.raw: $(src)/vdso.lds $(obj-vdso) FORCE
|
|
$(call if_changed,vdsold)
|
|
|
|
$(obj)/vdso.so.dbg: $(obj)/vdso.so.raw $(obj)/vdsomunge FORCE
|
|
$(call if_changed,vdsomunge)
|
|
|
|
# Strip rule for the .so file
|
|
$(obj)/%.so: OBJCOPYFLAGS := -S
|
|
$(obj)/%.so: $(obj)/%.so.dbg FORCE
|
|
$(call if_changed,objcopy)
|
|
|
|
# Actual build commands
|
|
quiet_cmd_vdsold = VDSO $@
|
|
cmd_vdsold = $(CC) $(c_flags) $(VDSO_LDFLAGS) \
|
|
-Wl,-T $(filter %.lds,$^) $(filter %.o,$^) -o $@
|
|
|
|
quiet_cmd_vdsomunge = MUNGE $@
|
|
cmd_vdsomunge = $(objtree)/$(obj)/vdsomunge $< $@
|
|
|
|
#
|
|
# Install the unstripped copy of vdso.so.dbg. If our toolchain
|
|
# supports build-id, install .build-id links as well.
|
|
#
|
|
# Cribbed from arch/x86/vdso/Makefile.
|
|
#
|
|
quiet_cmd_vdso_install = INSTALL $<
|
|
define cmd_vdso_install
|
|
cp $< "$(MODLIB)/vdso/vdso.so"; \
|
|
if readelf -n $< | grep -q 'Build ID'; then \
|
|
buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \
|
|
first=`echo $$buildid | cut -b-2`; \
|
|
last=`echo $$buildid | cut -b3-`; \
|
|
mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \
|
|
ln -sf "../../vdso.so" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \
|
|
fi
|
|
endef
|
|
|
|
$(MODLIB)/vdso: FORCE
|
|
@mkdir -p $(MODLIB)/vdso
|
|
|
|
PHONY += vdso_install
|
|
vdso_install: $(obj)/vdso.so.dbg $(MODLIB)/vdso FORCE
|
|
$(call cmd,vdso_install)
|