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 CFLAGS_vgettimeofday-32.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) 14 CFLAGS_vgettimeofday-32.o += $(call cc-option, -fno-stack-protector) 15 CFLAGS_vgettimeofday-32.o += -DDISABLE_BRANCH_PROFILING 16 CFLAGS_vgettimeofday-32.o += -ffreestanding -fasynchronous-unwind-tables 17 CFLAGS_REMOVE_vgettimeofday-32.o = $(CC_FLAGS_FTRACE) 18 CFLAGS_REMOVE_vgettimeofday-32.o += -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc 19 # This flag is supported by clang for 64-bit but not 32-bit so it will cause 20 # an unused command line flag warning for this file. 21 ifdef CONFIG_CC_IS_CLANG 22 CFLAGS_REMOVE_vgettimeofday-32.o += -fno-stack-clash-protection 23 endif 24 CFLAGS_vgettimeofday-64.o += -include $(c-gettimeofday-y) 25 CFLAGS_vgettimeofday-64.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) 26 CFLAGS_vgettimeofday-64.o += $(call cc-option, -fno-stack-protector) 27 CFLAGS_vgettimeofday-64.o += -DDISABLE_BRANCH_PROFILING 28 CFLAGS_vgettimeofday-64.o += -ffreestanding -fasynchronous-unwind-tables 29 CFLAGS_REMOVE_vgettimeofday-64.o = $(CC_FLAGS_FTRACE) 30# Go prior to 1.16.x assumes r30 is not clobbered by any VDSO code. That used to be true 31# by accident when the VDSO was hand-written asm code, but may not be now that the VDSO is 32# compiler generated. To avoid breaking Go tell GCC not to use r30. Impact on code 33# generation is minimal, it will just use r29 instead. 34 CFLAGS_vgettimeofday-64.o += $(call cc-option, -ffixed-r30) 35endif 36 37# Build rules 38 39ifdef CROSS32_COMPILE 40 VDSOCC := $(CROSS32_COMPILE)gcc 41else 42 VDSOCC := $(CC) 43endif 44 45targets := $(obj-vdso32) vdso32.so.dbg vgettimeofday-32.o 46obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32)) 47targets += $(obj-vdso64) vdso64.so.dbg vgettimeofday-64.o 48obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64)) 49 50ccflags-y := -fno-common -fno-builtin 51ldflags-y := -Wl,--hash-style=both -nostdlib -shared -z noexecstack $(CLANG_FLAGS) 52ldflags-$(CONFIG_LD_IS_LLD) += $(call cc-option,--ld-path=$(LD),-fuse-ld=lld) 53ldflags-$(CONFIG_LD_ORPHAN_WARN) += -Wl,--orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL) 54 55# Filter flags that clang will warn are unused for linking 56ldflags-y += $(filter-out $(CC_AUTO_VAR_INIT_ZERO_ENABLER) $(CC_FLAGS_FTRACE) -Wa$(comma)%, $(KBUILD_CFLAGS)) 57 58CC32FLAGS := -m32 59LD32FLAGS := -Wl,-soname=linux-vdso32.so.1 60AS32FLAGS := -D__VDSO32__ 61 62LD64FLAGS := -Wl,-soname=linux-vdso64.so.1 63AS64FLAGS := -D__VDSO64__ 64 65targets += vdso32.lds 66CPPFLAGS_vdso32.lds += -P -C -Upowerpc 67targets += vdso64.lds 68CPPFLAGS_vdso64.lds += -P -C 69 70# link rule for the .so file, .lds has to be first 71$(obj)/vdso32.so.dbg: $(obj)/vdso32.lds $(obj-vdso32) $(obj)/vgettimeofday-32.o FORCE 72 $(call if_changed,vdso32ld_and_check) 73$(obj)/vdso64.so.dbg: $(obj)/vdso64.lds $(obj-vdso64) $(obj)/vgettimeofday-64.o FORCE 74 $(call if_changed,vdso64ld_and_check) 75 76# assembly rules for the .S files 77$(obj-vdso32): %-32.o: %.S FORCE 78 $(call if_changed_dep,vdso32as) 79$(obj)/vgettimeofday-32.o: %-32.o: %.c FORCE 80 $(call if_changed_dep,vdso32cc) 81$(obj-vdso64): %-64.o: %.S FORCE 82 $(call if_changed_dep,vdso64as) 83$(obj)/vgettimeofday-64.o: %-64.o: %.c FORCE 84 $(call if_changed_dep,cc_o_c) 85 86# Generate VDSO offsets using helper script 87gen-vdso32sym := $(src)/gen_vdso32_offsets.sh 88quiet_cmd_vdso32sym = VDSO32SYM $@ 89 cmd_vdso32sym = $(NM) $< | $(gen-vdso32sym) | LC_ALL=C sort > $@ 90gen-vdso64sym := $(src)/gen_vdso64_offsets.sh 91quiet_cmd_vdso64sym = VDSO64SYM $@ 92 cmd_vdso64sym = $(NM) $< | $(gen-vdso64sym) | LC_ALL=C sort > $@ 93 94include/generated/vdso32-offsets.h: $(obj)/vdso32.so.dbg FORCE 95 $(call if_changed,vdso32sym) 96include/generated/vdso64-offsets.h: $(obj)/vdso64.so.dbg FORCE 97 $(call if_changed,vdso64sym) 98 99# actual build commands 100quiet_cmd_vdso32ld_and_check = VDSO32L $@ 101 cmd_vdso32ld_and_check = $(VDSOCC) $(ldflags-y) $(CC32FLAGS) $(LD32FLAGS) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^); $(cmd_vdso_check) 102quiet_cmd_vdso32as = VDSO32A $@ 103 cmd_vdso32as = $(VDSOCC) $(a_flags) $(CC32FLAGS) $(AS32FLAGS) -c -o $@ $< 104quiet_cmd_vdso32cc = VDSO32C $@ 105 cmd_vdso32cc = $(VDSOCC) $(c_flags) $(CC32FLAGS) -c -o $@ $< 106 107quiet_cmd_vdso64ld_and_check = VDSO64L $@ 108 cmd_vdso64ld_and_check = $(VDSOCC) $(ldflags-y) $(LD64FLAGS) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^); $(cmd_vdso_check) 109quiet_cmd_vdso64as = VDSO64A $@ 110 cmd_vdso64as = $(VDSOCC) $(a_flags) $(AS64FLAGS) -c -o $@ $< 111