Makefile 7.1 KB

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  1. # SPDX-License-Identifier: GPL-2.0
  2. #
  3. # Building vDSO images for x86.
  4. #
  5. # Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
  6. # the inclusion of generic Makefile.
  7. ARCH_REL_TYPE_ABS := R_X86_64_JUMP_SLOT|R_X86_64_GLOB_DAT|R_X86_64_RELATIVE|
  8. ARCH_REL_TYPE_ABS += R_386_GLOB_DAT|R_386_JMP_SLOT|R_386_RELATIVE
  9. include $(srctree)/lib/vdso/Makefile
  10. # Sanitizer runtimes are unavailable and cannot be linked here.
  11. KASAN_SANITIZE := n
  12. KMSAN_SANITIZE_vclock_gettime.o := n
  13. KMSAN_SANITIZE_vgetcpu.o := n
  14. UBSAN_SANITIZE := n
  15. KCSAN_SANITIZE := n
  16. OBJECT_FILES_NON_STANDARD := y
  17. # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
  18. KCOV_INSTRUMENT := n
  19. VDSO64-$(CONFIG_X86_64) := y
  20. VDSOX32-$(CONFIG_X86_X32_ABI) := y
  21. VDSO32-$(CONFIG_X86_32) := y
  22. VDSO32-$(CONFIG_IA32_EMULATION) := y
  23. # files to link into the vdso
  24. vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o
  25. vobjs32-y := vdso32/note.o vdso32/system_call.o vdso32/sigreturn.o
  26. vobjs32-y += vdso32/vclock_gettime.o
  27. vobjs-$(CONFIG_X86_SGX) += vsgx.o
  28. # files to link into kernel
  29. obj-y += vma.o extable.o
  30. KASAN_SANITIZE_vma.o := y
  31. UBSAN_SANITIZE_vma.o := y
  32. KCSAN_SANITIZE_vma.o := y
  33. OBJECT_FILES_NON_STANDARD_vma.o := n
  34. # vDSO images to build
  35. vdso_img-$(VDSO64-y) += 64
  36. vdso_img-$(VDSOX32-y) += x32
  37. vdso_img-$(VDSO32-y) += 32
  38. obj-$(VDSO32-y) += vdso32-setup.o
  39. vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
  40. vobjs32 := $(foreach F,$(vobjs32-y),$(obj)/$F)
  41. $(obj)/vdso.o: $(obj)/vdso.so
  42. targets += vdso.lds $(vobjs-y)
  43. targets += vdso32/vdso32.lds $(vobjs32-y)
  44. # Build the vDSO image C files and link them in.
  45. vdso_img_objs := $(vdso_img-y:%=vdso-image-%.o)
  46. vdso_img_cfiles := $(vdso_img-y:%=vdso-image-%.c)
  47. vdso_img_sodbg := $(vdso_img-y:%=vdso%.so.dbg)
  48. obj-y += $(vdso_img_objs)
  49. targets += $(vdso_img_cfiles)
  50. targets += $(vdso_img_sodbg) $(vdso_img-y:%=vdso%.so)
  51. CPPFLAGS_vdso.lds += -P -C
  52. VDSO_LDFLAGS_vdso.lds = -m elf_x86_64 -soname linux-vdso.so.1 --no-undefined \
  53. -z max-page-size=4096
  54. $(obj)/vdso64.so.dbg: $(obj)/vdso.lds $(vobjs) FORCE
  55. $(call if_changed,vdso_and_check)
  56. HOST_EXTRACFLAGS += -I$(srctree)/tools/include -I$(srctree)/include/uapi -I$(srctree)/arch/$(SUBARCH)/include/uapi
  57. hostprogs += vdso2c
  58. quiet_cmd_vdso2c = VDSO2C $@
  59. cmd_vdso2c = $(obj)/vdso2c $< $(<:%.dbg=%) $@
  60. $(obj)/vdso-image-%.c: $(obj)/vdso%.so.dbg $(obj)/vdso%.so $(obj)/vdso2c FORCE
  61. $(call if_changed,vdso2c)
  62. #
  63. # Don't omit frame pointers for ease of userspace debugging, but do
  64. # optimize sibling calls.
  65. #
  66. CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
  67. $(filter -g%,$(KBUILD_CFLAGS)) -fno-stack-protector \
  68. -fno-omit-frame-pointer -foptimize-sibling-calls \
  69. -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO
  70. ifdef CONFIG_RETPOLINE
  71. ifneq ($(RETPOLINE_VDSO_CFLAGS),)
  72. CFL += $(RETPOLINE_VDSO_CFLAGS)
  73. endif
  74. endif
  75. $(vobjs): KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL)
  76. $(vobjs): KBUILD_AFLAGS += -DBUILD_VDSO
  77. #
  78. # vDSO code runs in userspace and -pg doesn't help with profiling anyway.
  79. #
  80. CFLAGS_REMOVE_vclock_gettime.o = -pg
  81. CFLAGS_REMOVE_vdso32/vclock_gettime.o = -pg
  82. CFLAGS_REMOVE_vgetcpu.o = -pg
  83. CFLAGS_REMOVE_vsgx.o = -pg
  84. #
  85. # X32 processes use x32 vDSO to access 64bit kernel data.
  86. #
  87. # Build x32 vDSO image:
  88. # 1. Compile x32 vDSO as 64bit.
  89. # 2. Convert object files to x32.
  90. # 3. Build x32 VDSO image with x32 objects, which contains 64bit codes
  91. # so that it can reach 64bit address space with 64bit pointers.
  92. #
  93. CPPFLAGS_vdsox32.lds = $(CPPFLAGS_vdso.lds)
  94. VDSO_LDFLAGS_vdsox32.lds = -m elf32_x86_64 -soname linux-vdso.so.1 \
  95. -z max-page-size=4096
  96. # x32-rebranded versions
  97. vobjx32s-y := $(vobjs-y:.o=-x32.o)
  98. # same thing, but in the output directory
  99. vobjx32s := $(foreach F,$(vobjx32s-y),$(obj)/$F)
  100. # Convert 64bit object file to x32 for x32 vDSO.
  101. quiet_cmd_x32 = X32 $@
  102. cmd_x32 = $(OBJCOPY) -O elf32-x86-64 $< $@
  103. $(obj)/%-x32.o: $(obj)/%.o FORCE
  104. $(call if_changed,x32)
  105. targets += vdsox32.lds $(vobjx32s-y)
  106. $(obj)/%.so: OBJCOPYFLAGS := -S --remove-section __ex_table
  107. $(obj)/%.so: $(obj)/%.so.dbg FORCE
  108. $(call if_changed,objcopy)
  109. $(obj)/vdsox32.so.dbg: $(obj)/vdsox32.lds $(vobjx32s) FORCE
  110. $(call if_changed,vdso_and_check)
  111. CPPFLAGS_vdso32/vdso32.lds = $(CPPFLAGS_vdso.lds)
  112. VDSO_LDFLAGS_vdso32.lds = -m elf_i386 -soname linux-gate.so.1
  113. KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) -DBUILD_VDSO
  114. $(obj)/vdso32.so.dbg: KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
  115. $(obj)/vdso32.so.dbg: asflags-$(CONFIG_X86_64) += -m32
  116. KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS))
  117. KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32))
  118. KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32))
  119. KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32))
  120. KBUILD_CFLAGS_32 := $(filter-out $(RANDSTRUCT_CFLAGS),$(KBUILD_CFLAGS_32))
  121. KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32))
  122. KBUILD_CFLAGS_32 := $(filter-out $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS_32))
  123. KBUILD_CFLAGS_32 := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS_32))
  124. KBUILD_CFLAGS_32 := $(filter-out $(CC_FLAGS_CFI),$(KBUILD_CFLAGS_32))
  125. KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic
  126. KBUILD_CFLAGS_32 += -fno-stack-protector
  127. KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)
  128. KBUILD_CFLAGS_32 += -fno-omit-frame-pointer
  129. KBUILD_CFLAGS_32 += -DDISABLE_BRANCH_PROFILING
  130. ifdef CONFIG_RETPOLINE
  131. ifneq ($(RETPOLINE_VDSO_CFLAGS),)
  132. KBUILD_CFLAGS_32 += $(RETPOLINE_VDSO_CFLAGS)
  133. endif
  134. endif
  135. $(obj)/vdso32.so.dbg: KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
  136. $(obj)/vdso32.so.dbg: $(obj)/vdso32/vdso32.lds $(vobjs32) FORCE
  137. $(call if_changed,vdso_and_check)
  138. #
  139. # The DSO images are built using a special linker script.
  140. #
  141. quiet_cmd_vdso = VDSO $@
  142. cmd_vdso = $(LD) -o $@ \
  143. $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
  144. -T $(filter %.lds,$^) $(filter %.o,$^) && \
  145. sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
  146. VDSO_LDFLAGS = -shared --hash-style=both --build-id=sha1 \
  147. $(call ld-option, --eh-frame-hdr) -Bsymbolic -z noexecstack
  148. GCOV_PROFILE := n
  149. quiet_cmd_vdso_and_check = VDSO $@
  150. cmd_vdso_and_check = $(cmd_vdso); $(cmd_vdso_check)
  151. #
  152. # Install the unstripped copies of vdso*.so. If our toolchain supports
  153. # build-id, install .build-id links as well.
  154. #
  155. quiet_cmd_vdso_install = INSTALL $(@:install_%=%)
  156. define cmd_vdso_install
  157. cp $< "$(MODLIB)/vdso/$(@:install_%=%)"; \
  158. if readelf -n $< |grep -q 'Build ID'; then \
  159. buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \
  160. first=`echo $$buildid | cut -b-2`; \
  161. last=`echo $$buildid | cut -b3-`; \
  162. mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \
  163. ln -sf "../../$(@:install_%=%)" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \
  164. fi
  165. endef
  166. vdso_img_insttargets := $(vdso_img_sodbg:%.dbg=install_%)
  167. $(MODLIB)/vdso: FORCE
  168. @mkdir -p $(MODLIB)/vdso
  169. $(vdso_img_insttargets): install_%: $(obj)/%.dbg $(MODLIB)/vdso
  170. $(call cmd,vdso_install)
  171. PHONY += vdso_install $(vdso_img_insttargets)
  172. vdso_install: $(vdso_img_insttargets)
  173. clean-files := vdso32.so vdso32.so.dbg vdso64* vdso-image-*.c vdsox32.so*