1 # SPDX-License-Identifier: GPL-2.0
6 # Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
7 # the inclusion of generic Makefile.
8 ARCH_REL_TYPE_ABS := R_ARM_JUMP_SLOT|R_ARM_GLOB_DAT|R_ARM_ABS32
9 include $(srctree)/lib/vdso/Makefile
11 # Same as cc-*option, but using CC_COMPAT instead of CC
12 ifeq ($(CONFIG_CC_IS_CLANG), y)
13 COMPAT_GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE_COMPAT)elfedit))
14 COMPAT_GCC_TOOLCHAIN := $(realpath $(COMPAT_GCC_TOOLCHAIN_DIR)/..)
16 CC_COMPAT_CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%))
17 CC_COMPAT_CLANG_FLAGS += --prefix=$(COMPAT_GCC_TOOLCHAIN_DIR)
18 CC_COMPAT_CLANG_FLAGS += -no-integrated-as -Qunused-arguments
19 ifneq ($(COMPAT_GCC_TOOLCHAIN),)
20 CC_COMPAT_CLANG_FLAGS += --gcc-toolchain=$(COMPAT_GCC_TOOLCHAIN)
24 CC_COMPAT += $(CC_COMPAT_CLANG_FLAGS)
26 CC_COMPAT ?= $(CROSS_COMPILE_COMPAT)gcc
29 cc32-option = $(call try-run,\
30 $(CC_COMPAT) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
31 cc32-disable-warning = $(call try-run,\
32 $(CC_COMPAT) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
33 cc32-ldoption = $(call try-run,\
34 $(CC_COMPAT) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
35 cc32-as-instr = $(call try-run,\
36 printf "%b\n" "$(1)" | $(CC_COMPAT) $(VDSO_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
38 # We cannot use the global flags to compile the vDSO files, the main reason
39 # being that the 32-bit compiler may be older than the main (64-bit) compiler
40 # and therefore may not understand flags set using $(cc-option ...). Besides,
41 # arch-specific options should be taken from the arm Makefile instead of the
43 # As a result we set our own flags here.
45 # KBUILD_CPPFLAGS and NOSTDINC_FLAGS from top-level Makefile
46 VDSO_CPPFLAGS := -D__KERNEL__ -nostdinc -isystem $(shell $(CC_COMPAT) -print-file-name=include)
47 VDSO_CPPFLAGS += $(LINUXINCLUDE)
49 # Common C and assembly flags
50 # From top-level Makefile
51 VDSO_CAFLAGS := $(VDSO_CPPFLAGS)
52 ifneq ($(shell $(CC_COMPAT) --version 2>&1 | head -n 1 | grep clang),)
53 VDSO_CAFLAGS += --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%))
56 VDSO_CAFLAGS += $(call cc32-option,-fno-PIE)
57 ifdef CONFIG_DEBUG_INFO
62 VDSO_CAFLAGS += $(call cc32-option,-fno-dwarf2-cfi-asm)
63 VDSO_CAFLAGS += -mabi=aapcs-linux -mfloat-abi=soft
64 ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
65 VDSO_CAFLAGS += -mbig-endian
67 VDSO_CAFLAGS += -mlittle-endian
70 # From arm vDSO Makefile
71 VDSO_CAFLAGS += -fPIC -fno-builtin -fno-stack-protector
72 VDSO_CAFLAGS += -DDISABLE_BRANCH_PROFILING
75 # Try to compile for ARMv8. If the compiler is too old and doesn't support it,
76 # fall back to v7. There is no easy way to check for what architecture the code
77 # is being compiled, so define a macro specifying that (see arch/arm/Makefile).
78 VDSO_CAFLAGS += $(call cc32-option,-march=armv8-a -D__LINUX_ARM_ARCH__=8,\
79 -march=armv7-a -D__LINUX_ARM_ARCH__=7)
81 VDSO_CFLAGS := $(VDSO_CAFLAGS)
82 VDSO_CFLAGS += -DENABLE_COMPAT_VDSO=1
83 # KBUILD_CFLAGS from top-level Makefile
84 VDSO_CFLAGS += -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
85 -fno-strict-aliasing -fno-common \
86 -Werror-implicit-function-declaration \
87 -Wno-format-security \
90 # Some useful compiler-dependent flags from top-level Makefile
91 VDSO_CFLAGS += $(call cc32-option,-Wdeclaration-after-statement,)
92 VDSO_CFLAGS += $(call cc32-option,-Wno-pointer-sign)
93 VDSO_CFLAGS += $(call cc32-option,-fno-strict-overflow)
94 VDSO_CFLAGS += $(call cc32-option,-Werror=strict-prototypes)
95 VDSO_CFLAGS += $(call cc32-option,-Werror=date-time)
96 VDSO_CFLAGS += $(call cc32-option,-Werror=incompatible-pointer-types)
98 # The 32-bit compiler does not provide 128-bit integers, which are used in
99 # some headers that are indirectly included from the vDSO code.
100 # This hack makes the compiler happy and should trigger a warning/error if
101 # variables of such type are referenced.
102 VDSO_CFLAGS += -D__uint128_t='void*'
103 # Silence some warnings coming from headers that operate on long's
104 # (on GCC 4.8 or older, there is unfortunately no way to silence this warning)
105 VDSO_CFLAGS += $(call cc32-disable-warning,shift-count-overflow)
106 VDSO_CFLAGS += -Wno-int-to-pointer-cast
108 VDSO_AFLAGS := $(VDSO_CAFLAGS)
109 VDSO_AFLAGS += -D__ASSEMBLY__
111 # Check for binutils support for dmb ishld
112 dmbinstr := $(call cc32-as-instr,dmb ishld,-DCONFIG_AS_DMB_ISHLD=1)
114 VDSO_CFLAGS += $(dmbinstr)
115 VDSO_AFLAGS += $(dmbinstr)
117 VDSO_LDFLAGS := $(VDSO_CPPFLAGS)
118 # From arm vDSO Makefile
119 VDSO_LDFLAGS += -Wl,-Bsymbolic -Wl,--no-undefined -Wl,-soname=linux-vdso.so.1
120 VDSO_LDFLAGS += -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096
121 VDSO_LDFLAGS += -nostdlib -shared -mfloat-abi=soft
122 VDSO_LDFLAGS += -Wl,--hash-style=sysv
123 VDSO_LDFLAGS += -Wl,--build-id
124 VDSO_LDFLAGS += $(call cc32-ldoption,-fuse-ld=bfd)
127 # Borrow vdsomunge.c from the arm vDSO
128 # We have to use a relative path because scripts/Makefile.host prefixes
129 # $(hostprogs) with $(obj)
130 munge := ../../../arm/vdso/vdsomunge
131 hostprogs := $(munge)
134 c-obj-vdso-gettimeofday := vgettimeofday.o
135 asm-obj-vdso := sigreturn.o
137 ifneq ($(c-gettimeofday-y),)
138 VDSO_CFLAGS_gettimeofday_o += -include $(c-gettimeofday-y)
141 VDSO_CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os
144 targets := $(c-obj-vdso) $(c-obj-vdso-gettimeofday) $(asm-obj-vdso) vdso.so vdso.so.dbg vdso.so.raw
145 c-obj-vdso := $(addprefix $(obj)/, $(c-obj-vdso))
146 c-obj-vdso-gettimeofday := $(addprefix $(obj)/, $(c-obj-vdso-gettimeofday))
147 asm-obj-vdso := $(addprefix $(obj)/, $(asm-obj-vdso))
148 obj-vdso := $(c-obj-vdso) $(c-obj-vdso-gettimeofday) $(asm-obj-vdso)
152 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
154 # Force dependency (vdso.s includes vdso.so through incbin)
155 $(obj)/vdso.o: $(obj)/vdso.so
157 include/generated/vdso32-offsets.h: $(obj)/vdso.so.dbg FORCE
158 $(call if_changed,vdsosym)
160 # Strip rule for vdso.so
161 $(obj)/vdso.so: OBJCOPYFLAGS := -S
162 $(obj)/vdso.so: $(obj)/vdso.so.dbg FORCE
163 $(call if_changed,objcopy)
165 $(obj)/vdso.so.dbg: $(obj)/vdso.so.raw $(obj)/$(munge) FORCE
166 $(call if_changed,vdsomunge)
168 # Link rule for the .so file, .lds has to be first
169 $(obj)/vdso.so.raw: $(src)/vdso.lds $(obj-vdso) FORCE
170 $(call if_changed,vdsold_and_vdso_check)
172 # Compilation rules for the vDSO sources
173 $(c-obj-vdso): %.o: %.c FORCE
174 $(call if_changed_dep,vdsocc)
175 $(c-obj-vdso-gettimeofday): %.o: %.c FORCE
176 $(call if_changed_dep,vdsocc_gettimeofday)
177 $(asm-obj-vdso): %.o: %.S FORCE
178 $(call if_changed_dep,vdsoas)
180 # Actual build commands
181 quiet_cmd_vdsold_and_vdso_check = LD32 $@
182 cmd_vdsold_and_vdso_check = $(cmd_vdsold); $(cmd_vdso_check)
184 quiet_cmd_vdsold = LD32 $@
185 cmd_vdsold = $(CC_COMPAT) -Wp,-MD,$(depfile) $(VDSO_LDFLAGS) \
186 -Wl,-T $(filter %.lds,$^) $(filter %.o,$^) -o $@
187 quiet_cmd_vdsocc = CC32 $@
188 cmd_vdsocc = $(CC_COMPAT) -Wp,-MD,$(depfile) $(VDSO_CFLAGS) -c -o $@ $<
189 quiet_cmd_vdsocc_gettimeofday = CC32 $@
190 cmd_vdsocc_gettimeofday = $(CC_COMPAT) -Wp,-MD,$(depfile) $(VDSO_CFLAGS) $(VDSO_CFLAGS_gettimeofday_o) -c -o $@ $<
191 quiet_cmd_vdsoas = AS32 $@
192 cmd_vdsoas = $(CC_COMPAT) -Wp,-MD,$(depfile) $(VDSO_AFLAGS) -c -o $@ $<
194 quiet_cmd_vdsomunge = MUNGE $@
195 cmd_vdsomunge = $(obj)/$(munge) $< $@
197 # Generate vDSO offsets using helper script (borrowed from the 64-bit vDSO)
198 gen-vdsosym := $(srctree)/$(src)/../vdso/gen_vdso_offsets.sh
199 quiet_cmd_vdsosym = VDSOSYM $@
200 # The AArch64 nm should be able to read an AArch32 binary
201 cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
203 # Install commands for the unstripped file
204 quiet_cmd_vdso_install = INSTALL $@
205 cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/vdso32.so
207 vdso.so: $(obj)/vdso.so.dbg
208 @mkdir -p $(MODLIB)/vdso
209 $(call cmd,vdso_install)
211 vdso_install: vdso.so