1# SPDX-License-Identifier: GPL-2.0 2# Objects to go into the VDSO. 3 4KASAN_SANITIZE := n 5KCOV_INSTRUMENT := n 6 7# Include the generic Makefile to check the built vdso. 8include $(srctree)/lib/vdso/Makefile 9 10obj-vdso-y := elf.o vgetcpu.o vgettimeofday.o sigreturn.o 11 12# Common compiler flags between ABIs. 13ccflags-vdso := \ 14 $(filter -I%,$(KBUILD_CFLAGS)) \ 15 $(filter -E%,$(KBUILD_CFLAGS)) \ 16 $(filter -march=%,$(KBUILD_CFLAGS)) \ 17 $(filter -m%-float,$(KBUILD_CFLAGS)) \ 18 $(CLANG_FLAGS) \ 19 -D__VDSO__ 20 21cflags-vdso := $(ccflags-vdso) \ 22 -isystem $(shell $(CC) -print-file-name=include) \ 23 $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \ 24 -O2 -g -fno-strict-aliasing -fno-common -fno-builtin \ 25 -fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \ 26 $(call cc-option, -fno-asynchronous-unwind-tables) \ 27 $(call cc-option, -fno-stack-protector) 28aflags-vdso := $(ccflags-vdso) \ 29 -D__ASSEMBLY__ -Wa,-gdwarf-2 30 31ifneq ($(c-gettimeofday-y),) 32 CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y) 33endif 34 35# VDSO linker flags. 36ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \ 37 $(filter -E%,$(KBUILD_CFLAGS)) -nostdlib -shared \ 38 --hash-style=sysv --build-id -T 39 40GCOV_PROFILE := n 41 42# 43# Shared build commands. 44# 45 46quiet_cmd_vdsold_and_vdso_check = LD $@ 47 cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check) 48 49quiet_cmd_vdsoas_o_S = AS $@ 50 cmd_vdsoas_o_S = $(CC) $(a_flags) -c -o $@ $< 51 52# Generate VDSO offsets using helper script 53gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh 54quiet_cmd_vdsosym = VDSOSYM $@ 55 cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ 56 57include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE 58 $(call if_changed,vdsosym) 59 60# 61# Build native VDSO. 62# 63 64native-abi := $(filter -mabi=%,$(KBUILD_CFLAGS)) 65 66targets += $(obj-vdso-y) 67targets += vdso.lds vdso.so.dbg vdso.so 68 69obj-vdso := $(obj-vdso-y:%.o=$(obj)/%.o) 70 71$(obj-vdso): KBUILD_CFLAGS := $(cflags-vdso) $(native-abi) 72$(obj-vdso): KBUILD_AFLAGS := $(aflags-vdso) $(native-abi) 73 74$(obj)/vdso.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) $(native-abi) 75 76$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE 77 $(call if_changed,vdsold_and_vdso_check) 78 79$(obj)/vdso.so: OBJCOPYFLAGS := -S 80$(obj)/vdso.so: $(obj)/vdso.so.dbg FORCE 81 $(call if_changed,objcopy) 82 83obj-y += vdso.o 84 85$(obj)/vdso.o : $(obj)/vdso.so 86 87# install commands for the unstripped file 88quiet_cmd_vdso_install = INSTALL $@ 89 cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ 90 91vdso.so: $(obj)/vdso.so.dbg 92 @mkdir -p $(MODLIB)/vdso 93 $(call cmd,vdso_install) 94 95vdso_install: vdso.so 96