# # 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) # Disable gcov profiling for VDSO code GCOV_PROFILE := n # Workaround for bare-metal (ELF) toolchains that neglect to pass -shared # down to collect2, resulting in silent corruption of the vDSO image. ccflags-y += -Wl,-shared obj-y += vdso.o extra-y += vdso.lds 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 > $@ endef include/generated/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 |