1# SPDX-License-Identifier: GPL-2.0 2# Objects to go into the VDSO. 3 4KASAN_SANITIZE := n 5UBSAN_SANITIZE := n 6KCOV_INSTRUMENT := n 7 8# Include the generic Makefile to check the built vdso. 9include $(srctree)/lib/vdso/Makefile 10 11obj-vdso-y := elf.o vgetcpu.o vgettimeofday.o sigreturn.o 12 13# Common compiler flags between ABIs. 14ccflags-vdso := \ 15 $(filter -I%,$(KBUILD_CFLAGS)) \ 16 $(filter -E%,$(KBUILD_CFLAGS)) \ 17 $(filter -march=%,$(KBUILD_CFLAGS)) \ 18 $(filter -m%-float,$(KBUILD_CFLAGS)) \ 19 $(CLANG_FLAGS) \ 20 -D__VDSO__ 21 22cflags-vdso := $(ccflags-vdso) \ 23 -isystem $(shell $(CC) -print-file-name=include) \ 24 $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \ 25 -O2 -g -fno-strict-aliasing -fno-common -fno-builtin \ 26 -fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \ 27 $(call cc-option, -fno-asynchronous-unwind-tables) \ 28 $(call cc-option, -fno-stack-protector) 29aflags-vdso := $(ccflags-vdso) \ 30 -D__ASSEMBLY__ -Wa,-gdwarf-2 31 32ifneq ($(c-gettimeofday-y),) 33 CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y) 34endif 35 36# VDSO linker flags. 37ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \ 38 $(filter -E%,$(KBUILD_CFLAGS)) -nostdlib -shared \ 39 --hash-style=sysv --build-id -T 40 41GCOV_PROFILE := n 42 43# 44# Shared build commands. 45# 46 47quiet_cmd_vdsold_and_vdso_check = LD $@ 48 cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check) 49 50quiet_cmd_vdsoas_o_S = AS $@ 51 cmd_vdsoas_o_S = $(CC) $(a_flags) -c -o $@ $< 52 53# Generate VDSO offsets using helper script 54gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh 55quiet_cmd_vdsosym = VDSOSYM $@ 56 cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ 57 58include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE 59 $(call if_changed,vdsosym) 60 61# 62# Build native VDSO. 63# 64 65native-abi := $(filter -mabi=%,$(KBUILD_CFLAGS)) 66 67targets += $(obj-vdso-y) 68targets += vdso.lds vdso.so.dbg vdso.so 69 70obj-vdso := $(obj-vdso-y:%.o=$(obj)/%.o) 71 72$(obj-vdso): KBUILD_CFLAGS := $(cflags-vdso) $(native-abi) 73$(obj-vdso): KBUILD_AFLAGS := $(aflags-vdso) $(native-abi) 74 75$(obj)/vdso.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) $(native-abi) 76 77$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE 78 $(call if_changed,vdsold_and_vdso_check) 79 80$(obj)/vdso.so: OBJCOPYFLAGS := -S 81$(obj)/vdso.so: $(obj)/vdso.so.dbg FORCE 82 $(call if_changed,objcopy) 83 84obj-y += vdso.o 85 86$(obj)/vdso.o : $(obj)/vdso.so 87