mirror of
https://github.com/torvalds/linux.git
synced 2024-12-28 22:02:28 +00:00
1915e2ad1c
Building a kernel with CPU_BIG_ENDIAN fails if there are stale objects from a !CPU_BIG_ENDIAN build. Due to a missing FORCE prerequisite on an if_changed rule in the VDSO Makefile, we attempt to link a stale LE object into the new BE kernel. According to Documentation/kbuild/makefiles.txt, FORCE is required for if_changed rules and forgetting it is a common mistake, so fix it by 'Forcing' the build of vdso. This patch fixes build errors like these: arch/arm64/kernel/vdso/note.o: compiled for a little endian system and target is big endian failed to merge target specific data of file arch/arm64/kernel/vdso/note.o arch/arm64/kernel/vdso/sigreturn.o: compiled for a little endian system and target is big endian failed to merge target specific data of file arch/arm64/kernel/vdso/sigreturn.o Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Arun Chandran <achandran@mvista.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
64 lines
1.7 KiB
Makefile
64 lines
1.7 KiB
Makefile
#
|
|
# Building a vDSO image for AArch64.
|
|
#
|
|
# Author: Will Deacon <will.deacon@arm.com>
|
|
# Heavily based on the vDSO Makefiles for other archs.
|
|
#
|
|
|
|
obj-vdso := gettimeofday.o note.o sigreturn.o
|
|
|
|
# Build rules
|
|
targets := $(obj-vdso) vdso.so vdso.so.dbg
|
|
obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
|
|
|
|
ccflags-y := -shared -fno-common -fno-builtin
|
|
ccflags-y += -nostdlib -Wl,-soname=linux-vdso.so.1 \
|
|
$(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
|
|
|
|
obj-y += vdso.o
|
|
extra-y += vdso.lds vdso-offsets.h
|
|
CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
|
|
|
|
# Force dependency (incbin is bad)
|
|
$(obj)/vdso.o : $(obj)/vdso.so
|
|
|
|
# Link rule for the .so file, .lds has to be first
|
|
$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso)
|
|
$(call if_changed,vdsold)
|
|
|
|
# Strip rule for the .so file
|
|
$(obj)/%.so: OBJCOPYFLAGS := -S
|
|
$(obj)/%.so: $(obj)/%.so.dbg FORCE
|
|
$(call if_changed,objcopy)
|
|
|
|
# Generate VDSO offsets using helper script
|
|
gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
|
|
quiet_cmd_vdsosym = VDSOSYM $@
|
|
define cmd_vdsosym
|
|
$(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ && \
|
|
cp $@ include/generated/
|
|
endef
|
|
|
|
$(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
|
|
$(call if_changed,vdsosym)
|
|
|
|
# Assembly rules for the .S files
|
|
$(obj-vdso): %.o: %.S FORCE
|
|
$(call if_changed_dep,vdsoas)
|
|
|
|
# Actual build commands
|
|
quiet_cmd_vdsold = VDSOL $@
|
|
cmd_vdsold = $(CC) $(c_flags) -Wl,-n -Wl,-T $^ -o $@
|
|
quiet_cmd_vdsoas = VDSOA $@
|
|
cmd_vdsoas = $(CC) $(a_flags) -c -o $@ $<
|
|
|
|
# Install commands for the unstripped file
|
|
quiet_cmd_vdso_install = INSTALL $@
|
|
cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
|
|
|
|
vdso.so: $(obj)/vdso.so.dbg
|
|
@mkdir -p $(MODLIB)/vdso
|
|
$(call cmd,vdso_install)
|
|
|
|
vdso_install: vdso.so
|