1# SPDX-License-Identifier: GPL-2.0 2# 3# Building vDSO images for x86. 4# 5 6# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. 7KCOV_INSTRUMENT := n 8 9VDSO64-y := y 10 11vdso-install-$(VDSO64-y) += vdso.so 12 13 14# files to link into the vdso 15vobjs-y := vdso-note.o um_vdso.o 16 17# files to link into kernel 18obj-$(VDSO64-y) += vdso.o vma.o 19 20vobjs := $(foreach F,$(vobjs-y),$(obj)/$F) 21 22$(obj)/vdso.o: $(obj)/vdso.so 23 24targets += vdso.so vdso.so.dbg vdso.lds $(vobjs-y) 25 26CPPFLAGS_vdso.lds += -P -C 27 28VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \ 29 -Wl,-z,max-page-size=4096 30 31$(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so 32 33$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(vobjs) FORCE 34 $(call if_changed,vdso) 35 36$(obj)/%.so: OBJCOPYFLAGS := -S 37$(obj)/%.so: $(obj)/%.so.dbg FORCE 38 $(call if_changed,objcopy) 39 40# 41# Don't omit frame pointers for ease of userspace debugging, but do 42# optimize sibling calls. 43# 44CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \ 45 $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \ 46 -fno-omit-frame-pointer -foptimize-sibling-calls 47 48$(vobjs): KBUILD_CFLAGS += $(CFL) 49 50# 51# vDSO code runs in userspace and -pg doesn't help with profiling anyway. 52# 53CFLAGS_REMOVE_vdso-note.o = -pg -fprofile-arcs -ftest-coverage 54CFLAGS_REMOVE_um_vdso.o = -pg -fprofile-arcs -ftest-coverage 55 56# 57# The DSO images are built using a special linker script. 58# 59quiet_cmd_vdso = VDSO $@ 60 cmd_vdso = $(CC) -nostdlib -o $@ \ 61 $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \ 62 -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \ 63 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@' 64 65VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) 66GCOV_PROFILE := n 67 68# 69# Install the unstripped copy of vdso*.so listed in $(vdso-install-y). 70# 71quiet_cmd_vdso_install = INSTALL $@ 72 cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ 73$(vdso-install-y): %.so: $(obj)/%.so.dbg FORCE 74 @mkdir -p $(MODLIB)/vdso 75 $(call cmd,vdso_install) 76 77PHONY += vdso_install $(vdso-install-y) 78vdso_install: $(vdso-install-y) 79