xref: /linux/arch/mips/vdso/Makefile (revision 6203da9803017701da5782998157d9826215059d) 
1# SPDX-License-Identifier: GPL-2.0
2# Objects to go into the VDSO.
3
4# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
5# the inclusion of generic Makefile.
6ARCH_REL_TYPE_ABS := R_MIPS_JUMP_SLOT|R_MIPS_GLOB_DAT
7include $(srctree)/lib/vdso/Makefile
8
9obj-vdso-y := elf.o vgettimeofday.o sigreturn.o
10
11# Common compiler flags between ABIs.
12ccflags-vdso := \
13	$(filter -I%,$(KBUILD_CFLAGS)) \
14	$(filter -E%,$(KBUILD_CFLAGS)) \
15	$(filter -mmicromips,$(KBUILD_CFLAGS)) \
16	$(filter -march=%,$(KBUILD_CFLAGS)) \
17	$(filter -m%-float,$(KBUILD_CFLAGS)) \
18	$(filter -mno-loongson-%,$(KBUILD_CFLAGS)) \
19	-D__VDSO__
20
21ifndef CONFIG_64BIT
22ccflags-vdso += -DBUILD_VDSO32
23endif
24
25ifdef CONFIG_CC_IS_CLANG
26ccflags-vdso += $(filter --target=%,$(KBUILD_CFLAGS))
27endif
28
29#
30# The -fno-jump-tables flag only prevents the compiler from generating
31# jump tables but does not prevent the compiler from emitting absolute
32# offsets.
33cflags-vdso := $(ccflags-vdso) \
34	$(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \
35	-O3 -g -fPIC -fno-strict-aliasing -fno-common -fno-builtin -G 0 \
36	-mrelax-pic-calls $(call cc-option, -mexplicit-relocs) \
37	-fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \
38	$(call cc-option, -fno-asynchronous-unwind-tables) \
39	$(call cc-option, -fno-stack-protector)
40aflags-vdso := $(ccflags-vdso) \
41	-D__ASSEMBLY__ -Wa,-gdwarf-2
42
43ifneq ($(c-gettimeofday-y),)
44CFLAGS_vgettimeofday.o = -include $(c-gettimeofday-y)
45
46# config-n32-o32-env.c prepares the environment to build a 32bit vDSO
47# library on a 64bit kernel.
48# Note: Needs to be included before than the generic library.
49CFLAGS_vgettimeofday-o32.o = -include $(srctree)/$(src)/config-n32-o32-env.c -include $(c-gettimeofday-y)
50CFLAGS_vgettimeofday-n32.o = -include $(srctree)/$(src)/config-n32-o32-env.c -include $(c-gettimeofday-y)
51endif
52
53CFLAGS_REMOVE_vgettimeofday.o = -pg
54
55DISABLE_VDSO := n
56
57#
58# For the pre-R6 code in arch/mips/vdso/vdso.h for locating
59# the base address of VDSO, the linker will emit a R_MIPS_PC32
60# relocation in binutils > 2.25 but it will fail with older versions
61# because that relocation is not supported for that symbol. As a result
62# of which we are forced to disable the VDSO symbols when building
63# with < 2.25 binutils on pre-R6 kernels. For more references on why we
64# can't use other methods to get the base address of VDSO please refer to
65# the comments on that file.
66#
67ifndef CONFIG_CPU_MIPSR6
68  ifeq ($(call ld-ifversion, -lt, 225000000, y),y)
69    $(warning MIPS VDSO requires binutils >= 2.25)
70    DISABLE_VDSO := y
71  endif
72endif
73
74#
75# GCC (at least up to version 9.2) appears to emit function calls that make use
76# of the GOT when targeting microMIPS, which we can't use in the VDSO due to
77# the lack of relocations. As such, we disable the VDSO for microMIPS builds.
78#
79ifdef CONFIG_CPU_MICROMIPS
80  DISABLE_VDSO := y
81endif
82
83ifeq ($(DISABLE_VDSO),y)
84  obj-vdso-y := $(filter-out vgettimeofday.o, $(obj-vdso-y))
85  ccflags-vdso += -DDISABLE_MIPS_VDSO
86endif
87
88# VDSO linker flags.
89VDSO_LDFLAGS := \
90	-Wl,-Bsymbolic -Wl,--no-undefined -Wl,-soname=linux-vdso.so.1 \
91	$(addprefix -Wl$(comma),$(filter -E%,$(KBUILD_CFLAGS))) \
92	-nostdlib -shared -Wl,--hash-style=sysv -Wl,--build-id
93
94CFLAGS_REMOVE_vdso.o = -pg
95
96GCOV_PROFILE := n
97UBSAN_SANITIZE := n
98KCOV_INSTRUMENT := n
99
100# Check that we don't have PIC 'jalr t9' calls left
101quiet_cmd_vdso_mips_check = VDSOCHK $@
102      cmd_vdso_mips_check = if $(OBJDUMP) --disassemble $@ | egrep -h "jalr.*t9" > /dev/null; \
103		       then (echo >&2 "$@: PIC 'jalr t9' calls are not supported"; \
104			     rm -f $@; /bin/false); fi
105
106#
107# Shared build commands.
108#
109
110quiet_cmd_vdsold_and_vdso_check = LD      $@
111      cmd_vdsold_and_vdso_check = $(cmd_vdsold); $(cmd_vdso_check); $(cmd_vdso_mips_check)
112
113quiet_cmd_vdsold = VDSO    $@
114      cmd_vdsold = $(CC) $(c_flags) $(VDSO_LDFLAGS) \
115                   -Wl,-T $(filter %.lds,$^) $(filter %.o,$^) -o $@
116
117quiet_cmd_vdsoas_o_S = AS      $@
118      cmd_vdsoas_o_S = $(CC) $(a_flags) -c -o $@ $<
119
120# Strip rule for the raw .so files
121$(obj)/%.so.raw: OBJCOPYFLAGS := -S
122$(obj)/%.so.raw: $(obj)/%.so.dbg.raw FORCE
123	$(call if_changed,objcopy)
124
125hostprogs := genvdso
126
127quiet_cmd_genvdso = GENVDSO $@
128define cmd_genvdso
129	$(foreach file,$(filter %.raw,$^),cp $(file) $(file:%.raw=%) &&) \
130	$(obj)/genvdso $(<:%.raw=%) $(<:%.dbg.raw=%) $@ $(VDSO_NAME)
131endef
132
133#
134# Build native VDSO.
135#
136
137native-abi := $(filter -mabi=%,$(KBUILD_CFLAGS))
138
139targets += $(obj-vdso-y)
140targets += vdso.lds
141targets += vdso.so.dbg.raw vdso.so.raw
142targets += vdso.so.dbg vdso.so
143targets += vdso-image.c
144
145obj-vdso := $(obj-vdso-y:%.o=$(obj)/%.o)
146
147$(obj-vdso): KBUILD_CFLAGS := $(cflags-vdso) $(native-abi)
148$(obj-vdso): KBUILD_AFLAGS := $(aflags-vdso) $(native-abi)
149
150$(obj)/vdso.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) $(native-abi)
151
152$(obj)/vdso.so.dbg.raw: $(obj)/vdso.lds $(obj-vdso) FORCE
153	$(call if_changed,vdsold_and_vdso_check)
154
155$(obj)/vdso-image.c: $(obj)/vdso.so.dbg.raw $(obj)/vdso.so.raw \
156                     $(obj)/genvdso FORCE
157	$(call if_changed,genvdso)
158
159obj-y += vdso-image.o
160
161#
162# Build O32 VDSO.
163#
164
165# Define these outside the ifdef to ensure they are picked up by clean.
166targets += $(obj-vdso-y:%.o=%-o32.o)
167targets += vdso-o32.lds
168targets += vdso-o32.so.dbg.raw vdso-o32.so.raw
169targets += vdso-o32.so.dbg vdso-o32.so
170targets += vdso-o32-image.c
171
172ifdef CONFIG_MIPS32_O32
173
174obj-vdso-o32 := $(obj-vdso-y:%.o=$(obj)/%-o32.o)
175
176$(obj-vdso-o32): KBUILD_CFLAGS := $(cflags-vdso) -mabi=32
177$(obj-vdso-o32): KBUILD_AFLAGS := $(aflags-vdso) -mabi=32
178
179$(obj)/%-o32.o: $(src)/%.S FORCE
180	$(call if_changed_dep,vdsoas_o_S)
181
182$(obj)/%-o32.o: $(src)/%.c FORCE
183	$(call cmd,force_checksrc)
184	$(call if_changed_rule,cc_o_c)
185
186$(obj)/vdso-o32.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) -mabi=32
187$(obj)/vdso-o32.lds: $(src)/vdso.lds.S FORCE
188	$(call if_changed_dep,cpp_lds_S)
189
190$(obj)/vdso-o32.so.dbg.raw: $(obj)/vdso-o32.lds $(obj-vdso-o32) FORCE
191	$(call if_changed,vdsold_and_vdso_check)
192
193$(obj)/vdso-o32-image.c: VDSO_NAME := o32
194$(obj)/vdso-o32-image.c: $(obj)/vdso-o32.so.dbg.raw $(obj)/vdso-o32.so.raw \
195                         $(obj)/genvdso FORCE
196	$(call if_changed,genvdso)
197
198obj-y += vdso-o32-image.o
199
200endif
201
202#
203# Build N32 VDSO.
204#
205
206targets += $(obj-vdso-y:%.o=%-n32.o)
207targets += vdso-n32.lds
208targets += vdso-n32.so.dbg.raw vdso-n32.so.raw
209targets += vdso-n32.so.dbg vdso-n32.so
210targets += vdso-n32-image.c
211
212ifdef CONFIG_MIPS32_N32
213
214obj-vdso-n32 := $(obj-vdso-y:%.o=$(obj)/%-n32.o)
215
216$(obj-vdso-n32): KBUILD_CFLAGS := $(cflags-vdso) -mabi=n32
217$(obj-vdso-n32): KBUILD_AFLAGS := $(aflags-vdso) -mabi=n32
218
219$(obj)/%-n32.o: $(src)/%.S FORCE
220	$(call if_changed_dep,vdsoas_o_S)
221
222$(obj)/%-n32.o: $(src)/%.c FORCE
223	$(call cmd,force_checksrc)
224	$(call if_changed_rule,cc_o_c)
225
226$(obj)/vdso-n32.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) -mabi=n32
227$(obj)/vdso-n32.lds: $(src)/vdso.lds.S FORCE
228	$(call if_changed_dep,cpp_lds_S)
229
230$(obj)/vdso-n32.so.dbg.raw: $(obj)/vdso-n32.lds $(obj-vdso-n32) FORCE
231	$(call if_changed,vdsold_and_vdso_check)
232
233$(obj)/vdso-n32-image.c: VDSO_NAME := n32
234$(obj)/vdso-n32-image.c: $(obj)/vdso-n32.so.dbg.raw $(obj)/vdso-n32.so.raw \
235                         $(obj)/genvdso FORCE
236	$(call if_changed,genvdso)
237
238obj-y += vdso-n32-image.o
239
240endif
241
242# FIXME: Need install rule for debug.
243# Needs to deal with dependency for generation of dbg by cmd_genvdso...
244