1# SPDX-License-Identifier: GPL-2.0 2 3# List of files in the vdso, has to be asm only for now 4 5# Include the generic Makefile to check the built vdso. 6include $(srctree)/lib/vdso/Makefile 7 8obj-vdso32 = sigtramp32-32.o gettimeofday-32.o datapage-32.o cacheflush-32.o note-32.o getcpu-32.o 9obj-vdso64 = sigtramp64-64.o gettimeofday-64.o datapage-64.o cacheflush-64.o note-64.o getcpu-64.o 10 11ifneq ($(c-gettimeofday-y),) 12 CFLAGS_vgettimeofday-32.o += -include $(c-gettimeofday-y) 13# Go prior to 1.16.x assumes r30 is not clobbered by any VDSO code. That used to be true 14# by accident when the VDSO was hand-written asm code, but may not be now that the VDSO is 15# compiler generated. To avoid breaking Go tell GCC not to use r30. Impact on code 16# generation is minimal, it will just use r29 instead. 17 CFLAGS_vgettimeofday-64.o += -include $(c-gettimeofday-y) $(call cc-option, -ffixed-r30) 18endif 19 20# Build rules 21 22ifdef CROSS32_COMPILE 23 VDSOCC := $(CROSS32_COMPILE)gcc 24else 25 VDSOCC := $(CC) 26endif 27 28targets := $(obj-vdso32) vdso32.so.dbg vgettimeofday-32.o 29targets += crtsavres-32.o 30obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32)) 31targets += $(obj-vdso64) vdso64.so.dbg vgettimeofday-64.o 32obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64)) 33 34ccflags-y := -fno-common -fno-builtin 35ccflags-y += $(DISABLE_LATENT_ENTROPY_PLUGIN) 36ccflags-y += $(call cc-option, -fno-stack-protector) 37ccflags-y += -DDISABLE_BRANCH_PROFILING 38ccflags-y += -ffreestanding -fasynchronous-unwind-tables 39ccflags-remove-y := $(CC_FLAGS_FTRACE) 40ldflags-y := -Wl,--hash-style=both -nostdlib -shared -z noexecstack $(CLANG_FLAGS) 41ldflags-$(CONFIG_LD_IS_LLD) += $(call cc-option,--ld-path=$(LD),-fuse-ld=lld) 42ldflags-$(CONFIG_LD_ORPHAN_WARN) += -Wl,--orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL) 43 44# Filter flags that clang will warn are unused for linking 45ldflags-y += $(filter-out $(CC_AUTO_VAR_INIT_ZERO_ENABLER) $(CC_FLAGS_FTRACE) -Wa$(comma)%, $(KBUILD_CFLAGS)) 46 47CC32FLAGS := -m32 48CC32FLAGSREMOVE := -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc 49 # This flag is supported by clang for 64-bit but not 32-bit so it will cause 50 # an unused command line flag warning for this file. 51ifdef CONFIG_CC_IS_CLANG 52CC32FLAGSREMOVE += -fno-stack-clash-protection 53endif 54LD32FLAGS := -Wl,-soname=linux-vdso32.so.1 55AS32FLAGS := -D__VDSO32__ 56 57LD64FLAGS := -Wl,-soname=linux-vdso64.so.1 58AS64FLAGS := -D__VDSO64__ 59 60targets += vdso32.lds 61CPPFLAGS_vdso32.lds += -P -C -Upowerpc 62targets += vdso64.lds 63CPPFLAGS_vdso64.lds += -P -C 64 65# link rule for the .so file, .lds has to be first 66$(obj)/vdso32.so.dbg: $(obj)/vdso32.lds $(obj-vdso32) $(obj)/vgettimeofday-32.o $(obj)/crtsavres-32.o FORCE 67 $(call if_changed,vdso32ld_and_check) 68$(obj)/vdso64.so.dbg: $(obj)/vdso64.lds $(obj-vdso64) $(obj)/vgettimeofday-64.o FORCE 69 $(call if_changed,vdso64ld_and_check) 70 71# assembly rules for the .S files 72$(obj-vdso32): %-32.o: %.S FORCE 73 $(call if_changed_dep,vdso32as) 74$(obj)/crtsavres-32.o: %-32.o: $(srctree)/arch/powerpc/lib/crtsavres.S FORCE 75 $(call if_changed_dep,vdso32as) 76$(obj)/vgettimeofday-32.o: %-32.o: %.c FORCE 77 $(call if_changed_dep,vdso32cc) 78$(obj-vdso64): %-64.o: %.S FORCE 79 $(call if_changed_dep,vdso64as) 80$(obj)/vgettimeofday-64.o: %-64.o: %.c FORCE 81 $(call if_changed_dep,cc_o_c) 82 83# Generate VDSO offsets using helper script 84gen-vdso32sym := $(src)/gen_vdso32_offsets.sh 85quiet_cmd_vdso32sym = VDSO32SYM $@ 86 cmd_vdso32sym = $(NM) $< | $(gen-vdso32sym) | LC_ALL=C sort > $@ 87gen-vdso64sym := $(src)/gen_vdso64_offsets.sh 88quiet_cmd_vdso64sym = VDSO64SYM $@ 89 cmd_vdso64sym = $(NM) $< | $(gen-vdso64sym) | LC_ALL=C sort > $@ 90 91include/generated/vdso32-offsets.h: $(obj)/vdso32.so.dbg FORCE 92 $(call if_changed,vdso32sym) 93include/generated/vdso64-offsets.h: $(obj)/vdso64.so.dbg FORCE 94 $(call if_changed,vdso64sym) 95 96# actual build commands 97quiet_cmd_vdso32ld_and_check = VDSO32L $@ 98 cmd_vdso32ld_and_check = $(VDSOCC) $(ldflags-y) $(CC32FLAGS) $(LD32FLAGS) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^); $(cmd_vdso_check) 99quiet_cmd_vdso32as = VDSO32A $@ 100 cmd_vdso32as = $(VDSOCC) $(a_flags) $(CC32FLAGS) $(AS32FLAGS) -c -o $@ $< 101quiet_cmd_vdso32cc = VDSO32C $@ 102 cmd_vdso32cc = $(VDSOCC) $(filter-out $(CC32FLAGSREMOVE), $(c_flags)) $(CC32FLAGS) -c -o $@ $< 103 104quiet_cmd_vdso64ld_and_check = VDSO64L $@ 105 cmd_vdso64ld_and_check = $(VDSOCC) $(ldflags-y) $(LD64FLAGS) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^); $(cmd_vdso_check) 106quiet_cmd_vdso64as = VDSO64A $@ 107 cmd_vdso64as = $(VDSOCC) $(a_flags) $(AS64FLAGS) -c -o $@ $< 108