# Copied from arch/tile/kernel/vdso/Makefile # Symbols present in the vdso vdso-syms = rt_sigreturn ifdef CONFIG_64BIT vdso-syms += gettimeofday vdso-syms += clock_gettime vdso-syms += clock_getres endif vdso-syms += getcpu vdso-syms += flush_icache # Files to link into the vdso obj-vdso = $(patsubst %, %.o, $(vdso-syms)) # Build rules targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-dummy.o obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) obj-y += vdso.o vdso-syms.o CPPFLAGS_vdso.lds += -P -C -U$(ARCH) # Disable gcov profiling for VDSO code GCOV_PROFILE := n # Force dependency $(obj)/vdso.o: $(obj)/vdso.so # link rule for the .so file, .lds has to be first SYSCFLAGS_vdso.so.dbg = $(c_flags) $(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE $(call if_changed,vdsold) # We also create a special relocatable object that should mirror the symbol # table and layout of the linked DSO. With ld -R we can then refer to # these symbols in the kernel code rather than hand-coded addresses. SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \ -Wl,--hash-style=both $(obj)/vdso-dummy.o: $(src)/vdso.lds $(obj)/rt_sigreturn.o FORCE $(call if_changed,vdsold) LDFLAGS_vdso-syms.o := -r -R $(obj)/vdso-syms.o: $(obj)/vdso-dummy.o FORCE $(call if_changed,ld) # strip rule for the .so file $(obj)/%.so: OBJCOPYFLAGS := -S $(obj)/%.so: $(obj)/%.so.dbg FORCE $(call if_changed,objcopy) # actual build commands # The DSO images are built using a special linker script # Add -lgcc so rv32 gets static muldi3 and lshrdi3 definitions. # Make sure only to export the intended __vdso_xxx symbol offsets. quiet_cmd_vdsold = VDSOLD $@ cmd_vdsold = $(CC) $(KBUILD_CFLAGS) $(call cc-option, -no-pie) -nostdlib -nostartfiles $(SYSCFLAGS_$(@F)) \ -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp && \ $(CROSS_COMPILE)objcopy \ $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ # 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