1# 2# Building vDSO images for x86. 3# 4 5VDSO64-$(CONFIG_X86_64) := y 6VDSOX32-$(CONFIG_X86_X32_ABI) := y 7VDSO32-$(CONFIG_X86_32) := y 8VDSO32-$(CONFIG_COMPAT) := y 9 10vdso-install-$(VDSO64-y) += vdso.so 11vdso-install-$(VDSOX32-y) += vdsox32.so 12vdso-install-$(VDSO32-y) += $(vdso32-images) 13 14 15# files to link into the vdso 16vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o 17 18vobjs-$(VDSOX32-y) += $(vobjx32s-compat) 19 20# Filter out x32 objects. 21vobj64s := $(filter-out $(vobjx32s-compat),$(vobjs-y)) 22 23# files to link into kernel 24obj-$(VDSO64-y) += vma.o vdso.o 25obj-$(VDSOX32-y) += vdsox32.o 26obj-$(VDSO32-y) += vdso32.o vdso32-setup.o 27 28vobjs := $(foreach F,$(vobj64s),$(obj)/$F) 29 30$(obj)/vdso.o: $(obj)/vdso.so 31 32targets += vdso.so vdso.so.dbg vdso.lds $(vobjs-y) 33 34export CPPFLAGS_vdso.lds += -P -C 35 36VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \ 37 -Wl,--no-undefined \ 38 -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096 39 40$(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so 41 42$(obj)/vdso.so.dbg: $(src)/vdso.lds $(vobjs) FORCE 43 $(call if_changed,vdso) 44 45$(obj)/%.so: OBJCOPYFLAGS := -S 46$(obj)/%.so: $(obj)/%.so.dbg FORCE 47 $(call if_changed,objcopy) 48 49# 50# Don't omit frame pointers for ease of userspace debugging, but do 51# optimize sibling calls. 52# 53CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \ 54 $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \ 55 -fno-omit-frame-pointer -foptimize-sibling-calls 56 57$(vobjs): KBUILD_CFLAGS += $(CFL) 58 59# 60# vDSO code runs in userspace and -pg doesn't help with profiling anyway. 61# 62CFLAGS_REMOVE_vdso-note.o = -pg 63CFLAGS_REMOVE_vclock_gettime.o = -pg 64CFLAGS_REMOVE_vgetcpu.o = -pg 65CFLAGS_REMOVE_vvar.o = -pg 66 67targets += vdso-syms.lds 68obj-$(VDSO64-y) += vdso-syms.lds 69 70# 71# Match symbols in the DSO that look like VDSO*; produce a file of constants. 72# 73sed-vdsosym := -e 's/^00*/0/' \ 74 -e 's/^\([0-9a-fA-F]*\) . \(VDSO[a-zA-Z0-9_]*\)$$/\2 = 0x\1;/p' 75quiet_cmd_vdsosym = VDSOSYM $@ 76define cmd_vdsosym 77 $(NM) $< | LC_ALL=C sed -n $(sed-vdsosym) | LC_ALL=C sort > $@ 78endef 79 80$(obj)/%-syms.lds: $(obj)/%.so.dbg FORCE 81 $(call if_changed,vdsosym) 82 83# 84# X32 processes use x32 vDSO to access 64bit kernel data. 85# 86# Build x32 vDSO image: 87# 1. Compile x32 vDSO as 64bit. 88# 2. Convert object files to x32. 89# 3. Build x32 VDSO image with x32 objects, which contains 64bit codes 90# so that it can reach 64bit address space with 64bit pointers. 91# 92 93targets += vdsox32-syms.lds 94obj-$(VDSOX32-y) += vdsox32-syms.lds 95 96CPPFLAGS_vdsox32.lds = $(CPPFLAGS_vdso.lds) 97VDSO_LDFLAGS_vdsox32.lds = -Wl,-m,elf32_x86_64 \ 98 -Wl,-soname=linux-vdso.so.1 \ 99 -Wl,-z,max-page-size=4096 \ 100 -Wl,-z,common-page-size=4096 101 102vobjx32s-y := $(vobj64s:.o=-x32.o) 103vobjx32s := $(foreach F,$(vobjx32s-y),$(obj)/$F) 104 105# Convert 64bit object file to x32 for x32 vDSO. 106quiet_cmd_x32 = X32 $@ 107 cmd_x32 = $(OBJCOPY) -O elf32-x86-64 $< $@ 108 109$(obj)/%-x32.o: $(obj)/%.o FORCE 110 $(call if_changed,x32) 111 112targets += vdsox32.so vdsox32.so.dbg vdsox32.lds $(vobjx32s-y) 113 114$(obj)/vdsox32.o: $(src)/vdsox32.S $(obj)/vdsox32.so 115 116$(obj)/vdsox32.so.dbg: $(src)/vdsox32.lds $(vobjx32s) FORCE 117 $(call if_changed,vdso) 118 119# 120# Build multiple 32-bit vDSO images to choose from at boot time. 121# 122obj-$(VDSO32-y) += vdso32-syms.lds 123vdso32.so-$(VDSO32-y) += int80 124vdso32.so-$(CONFIG_COMPAT) += syscall 125vdso32.so-$(VDSO32-y) += sysenter 126 127vdso32-images = $(vdso32.so-y:%=vdso32-%.so) 128 129CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds) 130VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-soname=linux-gate.so.1 131 132# This makes sure the $(obj) subdirectory exists even though vdso32/ 133# is not a kbuild sub-make subdirectory. 134override obj-dirs = $(dir $(obj)) $(obj)/vdso32/ 135 136targets += vdso32/vdso32.lds 137targets += $(vdso32-images) $(vdso32-images:=.dbg) 138targets += vdso32/note.o $(vdso32.so-y:%=vdso32/%.o) 139 140extra-y += $(vdso32-images) 141 142$(obj)/vdso32.o: $(vdso32-images:%=$(obj)/%) 143 144KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) 145$(vdso32-images:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32) 146$(vdso32-images:%=$(obj)/%.dbg): asflags-$(CONFIG_X86_64) += -m32 147 148$(vdso32-images:%=$(obj)/%.dbg): $(obj)/vdso32-%.so.dbg: FORCE \ 149 $(obj)/vdso32/vdso32.lds \ 150 $(obj)/vdso32/note.o \ 151 $(obj)/vdso32/%.o 152 $(call if_changed,vdso) 153 154# Make vdso32-*-syms.lds from each image, and then make sure they match. 155# The only difference should be that some do not define VDSO32_SYSENTER_RETURN. 156 157targets += vdso32-syms.lds $(vdso32.so-y:%=vdso32-%-syms.lds) 158 159quiet_cmd_vdso32sym = VDSOSYM $@ 160define cmd_vdso32sym 161 if LC_ALL=C sort -u $(filter-out FORCE,$^) > $(@D)/.tmp_$(@F) && \ 162 $(foreach H,$(filter-out FORCE,$^),\ 163 if grep -q VDSO32_SYSENTER_RETURN $H; \ 164 then diff -u $(@D)/.tmp_$(@F) $H; \ 165 else sed /VDSO32_SYSENTER_RETURN/d $(@D)/.tmp_$(@F) | \ 166 diff -u - $H; fi &&) : ;\ 167 then mv -f $(@D)/.tmp_$(@F) $@; \ 168 else rm -f $(@D)/.tmp_$(@F); exit 1; \ 169 fi 170endef 171 172$(obj)/vdso32-syms.lds: $(vdso32.so-y:%=$(obj)/vdso32-%-syms.lds) FORCE 173 $(call if_changed,vdso32sym) 174 175# 176# The DSO images are built using a special linker script. 177# 178quiet_cmd_vdso = VDSO $@ 179 cmd_vdso = $(CC) -nostdlib -o $@ \ 180 $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \ 181 -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \ 182 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@' 183 184VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) 185GCOV_PROFILE := n 186 187# 188# Install the unstripped copy of vdso*.so listed in $(vdso-install-y). 189# 190quiet_cmd_vdso_install = INSTALL $@ 191 cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ 192$(vdso-install-y): %.so: $(obj)/%.so.dbg FORCE 193 @mkdir -p $(MODLIB)/vdso 194 $(call cmd,vdso_install) 195 196PHONY += vdso_install $(vdso-install-y) 197vdso_install: $(vdso-install-y) 198 199clean-files := vdso32-syscall* vdso32-sysenter* vdso32-int80* 200