1# SPDX-License-Identifier: GPL-2.0-only 2# Copied from arch/tile/kernel/vdso/Makefile 3 4# Include the generic Makefile to check the built vdso. 5include $(srctree)/lib/vdso/Makefile 6# Symbols present in the vdso 7vdso-syms = rt_sigreturn 8ifdef CONFIG_64BIT 9vdso-syms += vgettimeofday 10endif 11vdso-syms += getcpu 12vdso-syms += flush_icache 13vdso-syms += hwprobe 14vdso-syms += sys_hwprobe 15 16# Files to link into the vdso 17obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o 18 19ccflags-y := -fno-stack-protector 20ccflags-y += -DDISABLE_BRANCH_PROFILING 21 22ifneq ($(c-gettimeofday-y),) 23 CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y) 24endif 25 26CFLAGS_hwprobe.o += -fPIC 27 28# Build rules 29targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds 30obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) 31 32obj-y += vdso.o 33CPPFLAGS_vdso.lds += -P -C -U$(ARCH) 34ifneq ($(filter vgettimeofday, $(vdso-syms)),) 35CPPFLAGS_vdso.lds += -DHAS_VGETTIMEOFDAY 36endif 37 38# Disable -pg to prevent insert call site 39CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) 40CFLAGS_REMOVE_hwprobe.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) 41 42# Force dependency 43$(obj)/vdso.o: $(obj)/vdso.so 44 45# link rule for the .so file, .lds has to be first 46$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE 47 $(call if_changed,vdsold) 48LDFLAGS_vdso.so.dbg = -shared -soname=linux-vdso.so.1 \ 49 --build-id=sha1 --hash-style=both --eh-frame-hdr 50 51# strip rule for the .so file 52$(obj)/%.so: OBJCOPYFLAGS := -S 53$(obj)/%.so: $(obj)/%.so.dbg FORCE 54 $(call if_changed,objcopy) 55 56# Generate VDSO offsets using helper script 57gen-vdsosym := $(src)/gen_vdso_offsets.sh 58quiet_cmd_vdsosym = VDSOSYM $@ 59 cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ 60 61include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE 62 $(call if_changed,vdsosym) 63 64# actual build commands 65# The DSO images are built using a special linker script 66# Make sure only to export the intended __vdso_xxx symbol offsets. 67quiet_cmd_vdsold = VDSOLD $@ 68 cmd_vdsold = $(LD) $(ld_flags) -T $(filter-out FORCE,$^) -o $@.tmp && \ 69 $(OBJCOPY) $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \ 70 rm $@.tmp 71