diff options
Diffstat (limited to 'kernel/arch/x86/vdso/Makefile')
| -rw-r--r-- | kernel/arch/x86/vdso/Makefile | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/kernel/arch/x86/vdso/Makefile b/kernel/arch/x86/vdso/Makefile new file mode 100644 index 000000000..e97032069 --- /dev/null +++ b/kernel/arch/x86/vdso/Makefile @@ -0,0 +1,209 @@ +# +# Building vDSO images for x86. +# + +KBUILD_CFLAGS += $(DISABLE_LTO) +KASAN_SANITIZE := n + +VDSO64-$(CONFIG_X86_64) := y +VDSOX32-$(CONFIG_X86_X32_ABI) := y +VDSO32-$(CONFIG_X86_32) := y +VDSO32-$(CONFIG_COMPAT) := y + +# files to link into the vdso +vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o + +# files to link into kernel +obj-y += vma.o + +# vDSO images to build +vdso_img-$(VDSO64-y) += 64 +vdso_img-$(VDSOX32-y) += x32 +vdso_img-$(VDSO32-y) += 32-int80 +vdso_img-$(CONFIG_COMPAT) += 32-syscall +vdso_img-$(VDSO32-y) += 32-sysenter + +obj-$(VDSO32-y) += vdso32-setup.o + +vobjs := $(foreach F,$(vobjs-y),$(obj)/$F) + +$(obj)/vdso.o: $(obj)/vdso.so + +targets += vdso.lds $(vobjs-y) + +# Build the vDSO image C files and link them in. +vdso_img_objs := $(vdso_img-y:%=vdso-image-%.o) +vdso_img_cfiles := $(vdso_img-y:%=vdso-image-%.c) +vdso_img_sodbg := $(vdso_img-y:%=vdso%.so.dbg) +obj-y += $(vdso_img_objs) +targets += $(vdso_img_cfiles) +targets += $(vdso_img_sodbg) +.SECONDARY: $(vdso_img-y:%=$(obj)/vdso-image-%.c) \ + $(vdso_img-y:%=$(obj)/vdso%.so) + +export CPPFLAGS_vdso.lds += -P -C + +VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \ + -Wl,--no-undefined \ + -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096 \ + $(DISABLE_LTO) + +$(obj)/vdso64.so.dbg: $(src)/vdso.lds $(vobjs) FORCE + $(call if_changed,vdso) + +HOST_EXTRACFLAGS += -I$(srctree)/tools/include -I$(srctree)/include/uapi -I$(srctree)/arch/x86/include/uapi +hostprogs-y += vdso2c + +quiet_cmd_vdso2c = VDSO2C $@ +define cmd_vdso2c + $(obj)/vdso2c $< $(<:%.dbg=%) $@ +endef + +$(obj)/vdso-image-%.c: $(obj)/vdso%.so.dbg $(obj)/vdso%.so $(obj)/vdso2c FORCE + $(call if_changed,vdso2c) + +# +# Don't omit frame pointers for ease of userspace debugging, but do +# optimize sibling calls. +# +CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \ + $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \ + -fno-omit-frame-pointer -foptimize-sibling-calls \ + -DDISABLE_BRANCH_PROFILING + +$(vobjs): KBUILD_CFLAGS += $(CFL) + +# +# vDSO code runs in userspace and -pg doesn't help with profiling anyway. +# +CFLAGS_REMOVE_vdso-note.o = -pg +CFLAGS_REMOVE_vclock_gettime.o = -pg +CFLAGS_REMOVE_vgetcpu.o = -pg +CFLAGS_REMOVE_vvar.o = -pg + +# +# X32 processes use x32 vDSO to access 64bit kernel data. +# +# Build x32 vDSO image: +# 1. Compile x32 vDSO as 64bit. +# 2. Convert object files to x32. +# 3. Build x32 VDSO image with x32 objects, which contains 64bit codes +# so that it can reach 64bit address space with 64bit pointers. +# + +CPPFLAGS_vdsox32.lds = $(CPPFLAGS_vdso.lds) +VDSO_LDFLAGS_vdsox32.lds = -Wl,-m,elf32_x86_64 \ + -Wl,-soname=linux-vdso.so.1 \ + -Wl,-z,max-page-size=4096 \ + -Wl,-z,common-page-size=4096 + +# 64-bit objects to re-brand as x32 +vobjs64-for-x32 := $(filter-out $(vobjs-nox32),$(vobjs-y)) + +# x32-rebranded versions +vobjx32s-y := $(vobjs64-for-x32:.o=-x32.o) + +# same thing, but in the output directory +vobjx32s := $(foreach F,$(vobjx32s-y),$(obj)/$F) + +# Convert 64bit object file to x32 for x32 vDSO. +quiet_cmd_x32 = X32 $@ + cmd_x32 = $(OBJCOPY) -O elf32-x86-64 $< $@ + +$(obj)/%-x32.o: $(obj)/%.o FORCE + $(call if_changed,x32) + +targets += vdsox32.lds $(vobjx32s-y) + +$(obj)/%.so: OBJCOPYFLAGS := -S +$(obj)/%.so: $(obj)/%.so.dbg + $(call if_changed,objcopy) + +$(obj)/vdsox32.so.dbg: $(src)/vdsox32.lds $(vobjx32s) FORCE + $(call if_changed,vdso) + +# +# Build multiple 32-bit vDSO images to choose from at boot time. +# +vdso32.so-$(VDSO32-y) += int80 +vdso32.so-$(CONFIG_COMPAT) += syscall +vdso32.so-$(VDSO32-y) += sysenter + +vdso32-images = $(vdso32.so-y:%=vdso32-%.so) + +CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds) +VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-m,elf_i386 -Wl,-soname=linux-gate.so.1 + +# This makes sure the $(obj) subdirectory exists even though vdso32/ +# is not a kbuild sub-make subdirectory. +override obj-dirs = $(dir $(obj)) $(obj)/vdso32/ + +targets += vdso32/vdso32.lds +targets += vdso32/note.o vdso32/vclock_gettime.o $(vdso32.so-y:%=vdso32/%.o) +targets += vdso32/vclock_gettime.o + +$(obj)/vdso32.o: $(vdso32-images:%=$(obj)/%) + +KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) +$(vdso32-images:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32) +$(vdso32-images:%=$(obj)/%.dbg): asflags-$(CONFIG_X86_64) += -m32 + +KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS)) +KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32)) +KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32)) +KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32)) +KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic +KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector) +KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls) +KBUILD_CFLAGS_32 += -fno-omit-frame-pointer +KBUILD_CFLAGS_32 += -DDISABLE_BRANCH_PROFILING +$(vdso32-images:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32) + +$(vdso32-images:%=$(obj)/%.dbg): $(obj)/vdso32-%.so.dbg: FORCE \ + $(obj)/vdso32/vdso32.lds \ + $(obj)/vdso32/vclock_gettime.o \ + $(obj)/vdso32/note.o \ + $(obj)/vdso32/%.o + $(call if_changed,vdso) + +# +# The DSO images are built using a special linker script. +# +quiet_cmd_vdso = VDSO $@ + cmd_vdso = $(CC) -nostdlib -o $@ \ + $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \ + -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \ + sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@' + +VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) \ + $(call cc-ldoption, -Wl$(comma)--build-id) -Wl,-Bsymbolic $(LTO_CFLAGS) +GCOV_PROFILE := n + +# +# Install the unstripped copies of vdso*.so. If our toolchain supports +# build-id, install .build-id links as well. +# +quiet_cmd_vdso_install = INSTALL $(@:install_%=%) +define cmd_vdso_install + cp $< "$(MODLIB)/vdso/$(@:install_%=%)"; \ + if readelf -n $< |grep -q 'Build ID'; then \ + buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \ + first=`echo $$buildid | cut -b-2`; \ + last=`echo $$buildid | cut -b3-`; \ + mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \ + ln -sf "../../$(@:install_%=%)" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \ + fi +endef + +vdso_img_insttargets := $(vdso_img_sodbg:%.dbg=install_%) + +$(MODLIB)/vdso: FORCE + @mkdir -p $(MODLIB)/vdso + +$(vdso_img_insttargets): install_%: $(obj)/%.dbg $(MODLIB)/vdso FORCE + $(call cmd,vdso_install) + +PHONY += vdso_install $(vdso_img_insttargets) +vdso_install: $(vdso_img_insttargets) FORCE + +clean-files := vdso32-syscall* vdso32-sysenter* vdso32-int80* vdso64* vdso-image-*.c vdsox32.so* |