1# SPDX-License-Identifier: GPL-2.0 2 3# Include the generic Makefile to check the built vdso. 4include $(srctree)/lib/vdso/Makefile 5 6hostprogs := vdsomunge 7 8obj-vdso := vgettimeofday.o datapage.o note.o 9 10# Build rules 11targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.so.raw vdso.lds 12obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) 13 14ccflags-y := -fPIC -fno-common -fno-builtin -fno-stack-protector 15ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO32 16 17ldflags-$(CONFIG_CPU_ENDIAN_BE8) := --be8 18ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \ 19 -z max-page-size=4096 -shared $(ldflags-y) \ 20 --hash-style=sysv --build-id=sha1 \ 21 -T 22 23obj-$(CONFIG_VDSO) += vdso.o 24CPPFLAGS_vdso.lds += -P -C -U$(ARCH) 25 26CFLAGS_REMOVE_vdso.o = -pg 27 28# Force -O2 to avoid libgcc dependencies 29CFLAGS_REMOVE_vgettimeofday.o = -pg -Os $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) 30ifeq ($(c-gettimeofday-y),) 31CFLAGS_vgettimeofday.o = -O2 32else 33CFLAGS_vgettimeofday.o = -O2 -include $(c-gettimeofday-y) 34endif 35 36# Disable gcov profiling for VDSO code 37GCOV_PROFILE := n 38UBSAN_SANITIZE := n 39 40# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. 41KCOV_INSTRUMENT := n 42 43KASAN_SANITIZE := n 44 45# Force dependency 46$(obj)/vdso.o : $(obj)/vdso.so 47 48# Link rule for the .so file 49$(obj)/vdso.so.raw: $(obj)/vdso.lds $(obj-vdso) FORCE 50 $(call if_changed,vdsold_and_vdso_check) 51 52$(obj)/vdso.so.dbg: $(obj)/vdso.so.raw $(obj)/vdsomunge FORCE 53 $(call if_changed,vdsomunge) 54 55# Strip rule for the .so file 56$(obj)/%.so: OBJCOPYFLAGS := -S 57$(obj)/%.so: $(obj)/%.so.dbg FORCE 58 $(call if_changed,objcopy) 59 60# Actual build commands 61quiet_cmd_vdsold_and_vdso_check = LD $@ 62 cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check) 63 64quiet_cmd_vdsomunge = MUNGE $@ 65 cmd_vdsomunge = $(objtree)/$(obj)/vdsomunge $< $@ 66 67# 68# Install the unstripped copy of vdso.so.dbg. If our toolchain 69# supports build-id, install .build-id links as well. 70# 71# Cribbed from arch/x86/vdso/Makefile. 72# 73quiet_cmd_vdso_install = INSTALL $< 74define cmd_vdso_install 75 cp $< "$(MODLIB)/vdso/vdso.so"; \ 76 if readelf -n $< | grep -q 'Build ID'; then \ 77 buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \ 78 first=`echo $$buildid | cut -b-2`; \ 79 last=`echo $$buildid | cut -b3-`; \ 80 mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \ 81 ln -sf "../../vdso.so" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \ 82 fi 83endef 84 85$(MODLIB)/vdso: FORCE 86 @mkdir -p $(MODLIB)/vdso 87 88PHONY += vdso_install 89vdso_install: $(obj)/vdso.so.dbg $(MODLIB)/vdso 90 $(call cmd,vdso_install) 91