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.include 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 16ifdef CONFIG_VDSO_GETRANDOM 17vdso-syms += getrandom 18endif 19 20# Files to link into the vdso 21obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o 22 23ifdef CONFIG_VDSO_GETRANDOM 24obj-vdso += vgetrandom-chacha.o 25endif 26 27ccflags-y := -fno-stack-protector 28ccflags-y += -DDISABLE_BRANCH_PROFILING 29ccflags-y += -fno-builtin 30 31ifneq ($(c-gettimeofday-y),) 32 CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y) 33endif 34 35ifneq ($(c-getrandom-y),) 36 CFLAGS_getrandom.o += -fPIC -include $(c-getrandom-y) 37endif 38 39CFLAGS_hwprobe.o += -fPIC 40 41# Build rules 42targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds 43obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) 44 45obj-y += vdso.o 46CPPFLAGS_vdso.lds += -P -C -U$(ARCH) 47ifneq ($(filter vgettimeofday, $(vdso-syms)),) 48CPPFLAGS_vdso.lds += -DHAS_VGETTIMEOFDAY 49endif 50 51# Disable -pg to prevent insert call site 52CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) 53CFLAGS_REMOVE_getrandom.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) 54CFLAGS_REMOVE_hwprobe.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) 55 56# Force dependency 57$(obj)/vdso.o: $(obj)/vdso.so 58 59# link rule for the .so file, .lds has to be first 60$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE 61 $(call if_changed,vdsold_and_check) 62LDFLAGS_vdso.so.dbg = -shared -soname=linux-vdso.so.1 \ 63 --build-id=sha1 --eh-frame-hdr 64 65# strip rule for the .so file 66$(obj)/%.so: OBJCOPYFLAGS := -S 67$(obj)/%.so: $(obj)/%.so.dbg FORCE 68 $(call if_changed,objcopy) 69 70# Generate VDSO offsets using helper script 71gen-vdsosym := $(src)/gen_vdso_offsets.sh 72quiet_cmd_vdsosym = VDSOSYM $@ 73 cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ 74 75include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE 76 $(call if_changed,vdsosym) 77 78# actual build commands 79# The DSO images are built using a special linker script 80# Make sure only to export the intended __vdso_xxx symbol offsets. 81quiet_cmd_vdsold_and_check = VDSOLD $@ 82 cmd_vdsold_and_check = $(LD) $(ld_flags) -T $(filter-out FORCE,$^) -o $@.tmp && \ 83 $(OBJCOPY) $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \ 84 rm $@.tmp && \ 85 $(cmd_vdso_check) 86