1 # SPDX-License-Identifier: GPL-2.0 1 # SPDX-License-Identifier: GPL-2.0
2 # ============================================ 2 # ===========================================================================
3 # Module versions 3 # Module versions
4 # ============================================ 4 # ===========================================================================
5 # 5 #
6 # Stage one of module building created the fol 6 # Stage one of module building created the following:
7 # a) The individual .o files used for the modu 7 # a) The individual .o files used for the module
8 # b) A <module>.o file which is the .o files a 8 # b) A <module>.o file which is the .o files above linked together
9 # c) A <module>.mod file, listing the name of 9 # c) A <module>.mod file, listing the name of the preliminary <module>.o file,
10 # plus all .o files 10 # plus all .o files
11 # d) modules.order, which lists all the module 11 # d) modules.order, which lists all the modules
12 12
13 # Stage 2 is handled by this file and does the 13 # Stage 2 is handled by this file and does the following
14 # 1) Find all modules listed in modules.order 14 # 1) Find all modules listed in modules.order
15 # 2) modpost is then used to 15 # 2) modpost is then used to
16 # 3) create one <module>.mod.c file per modul !! 16 # 3) create one <module>.mod.c file pr. module
17 # 4) create one Module.symvers file with CRC 17 # 4) create one Module.symvers file with CRC for all exported symbols
18 18
19 # Step 3 is used to place certain information 19 # Step 3 is used to place certain information in the module's ELF
20 # section, including information such as: 20 # section, including information such as:
21 # Version magic (see include/linux/vermagic. 21 # Version magic (see include/linux/vermagic.h for full details)
22 # - Kernel release 22 # - Kernel release
23 # - SMP is CONFIG_SMP 23 # - SMP is CONFIG_SMP
24 # - PREEMPT is CONFIG_PREEMPT[_RT] 24 # - PREEMPT is CONFIG_PREEMPT[_RT]
25 # - GCC Version 25 # - GCC Version
26 # Module info 26 # Module info
27 # - Module version (MODULE_VERSION) 27 # - Module version (MODULE_VERSION)
28 # - Module alias'es (MODULE_ALIAS) 28 # - Module alias'es (MODULE_ALIAS)
29 # - Module license (MODULE_LICENSE) 29 # - Module license (MODULE_LICENSE)
30 # - See include/linux/module.h for more de 30 # - See include/linux/module.h for more details
31 31
32 # Step 4 is solely used to allow module versio 32 # Step 4 is solely used to allow module versioning in external modules,
33 # where the CRC of each module is retrieved fr 33 # where the CRC of each module is retrieved from the Module.symvers file.
34 34
>> 35 # KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined
>> 36 # symbols in the final module linking stage
>> 37 # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
>> 38 # This is solely useful to speed up test compiles
>> 39
35 PHONY := __modpost 40 PHONY := __modpost
36 __modpost: 41 __modpost:
37 42
38 include include/config/auto.conf 43 include include/config/auto.conf
39 include $(srctree)/scripts/Kbuild.include !! 44 include scripts/Kbuild.include
40 45
41 MODPOST = scripts/mod/modpost !! 46 # for ld_flags
>> 47 include scripts/Makefile.lib
42 48
43 modpost-args = !! 49 MODPOST = scripts/mod/modpost \
44 $(if $(CONFIG_MODULES),-M) <<
45 $(if $(CONFIG_MODVERSIONS),-m) 50 $(if $(CONFIG_MODVERSIONS),-m) \
46 $(if $(CONFIG_MODULE_SRCVERSION_ALL),- 51 $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \
47 $(if $(CONFIG_SECTION_MISMATCH_WARN_ON 52 $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \
48 $(if $(KBUILD_MODPOST_WARN),-w) !! 53 $(if $(KBUILD_MODPOST_WARN),-w) \
49 $(if $(KBUILD_NSDEPS),-d $(MODULES_NSD <<
50 $(if $(CONFIG_MODULE_ALLOW_MISSING_NAM <<
51 $(if $(findstring 1, $(KBUILD_EXTRA_WA <<
52 -o $@ 54 -o $@
53 55
54 modpost-deps := $(MODPOST) !! 56 ifdef MODPOST_VMLINUX
55 57
56 # 'make -i -k' ignores compile errors, and bui !! 58 quiet_cmd_modpost = MODPOST $@
57 ifneq ($(findstring i,$(filter-out --%,$(MAKEF !! 59 cmd_modpost = $(MODPOST) $<
58 modpost-args += -n <<
59 endif <<
60 60
61 # Read out modules.order to pass in modpost. !! 61 vmlinux.symvers: vmlinux.o
62 # Otherwise, allmodconfig would fail with "Arg !! 62 $(call cmd,modpost)
63 ifdef KBUILD_MODULES <<
64 modpost-args += -T $(MODORDER) <<
65 modpost-deps += $(MODORDER) <<
66 endif <<
67 63
68 ifeq ($(KBUILD_EXTMOD),) !! 64 __modpost: vmlinux.symvers
69 65
70 # Generate the list of in-tree objects in vmli !! 66 else
71 # -------------------------------------------- <<
72 67
73 # This is used to retrieve symbol versions gen !! 68 ifeq ($(KBUILD_EXTMOD),)
74 ifdef CONFIG_MODVERSIONS <<
75 vmlinux.symvers Module.symvers: .vmlinux.objs <<
76 endif <<
77 <<
78 # Ignore libgcc.a <<
79 # Some architectures do '$(CC) --print-libgcc- <<
80 # from the toolchain, but there is no EXPORT_S <<
81 <<
82 quiet_cmd_vmlinux_objs = GEN $@ <<
83 cmd_vmlinux_objs = \ <<
84 for f in $(real-prereqs); do \ <<
85 case $${f} in \ <<
86 *libgcc.a) ;; \ <<
87 *) $(AR) t $${f} ;; \ <<
88 esac \ <<
89 done > $@ <<
90 <<
91 targets += .vmlinux.objs <<
92 .vmlinux.objs: vmlinux.a $(KBUILD_VMLINUX_LIBS <<
93 $(call if_changed,vmlinux_objs) <<
94 <<
95 ifdef CONFIG_TRIM_UNUSED_KSYMS <<
96 ksym-wl := $(CONFIG_UNUSED_KSYMS_WHITELIST) <<
97 ksym-wl := $(if $(filter-out /%, $(ksym-wl)),$ <<
98 modpost-args += -t $(addprefix -u , $(ksym-wl) <<
99 modpost-deps += $(ksym-wl) <<
100 endif <<
101 69
102 ifeq ($(wildcard vmlinux.o),) !! 70 input-symdump := vmlinux.symvers
103 missing-input := vmlinux.o <<
104 output-symdump := modules-only.symvers 71 output-symdump := modules-only.symvers
105 else !! 72
106 modpost-args += vmlinux.o !! 73 quiet_cmd_cat = GEN $@
107 modpost-deps += vmlinux.o !! 74 cmd_cat = cat $(real-prereqs) > $@
108 output-symdump := $(if $(KBUILD_MODULES), Modu !! 75
>> 76 ifneq ($(wildcard vmlinux.symvers),)
>> 77
>> 78 __modpost: Module.symvers
>> 79 Module.symvers: vmlinux.symvers modules-only.symvers FORCE
>> 80 $(call if_changed,cat)
>> 81
>> 82 targets += Module.symvers
>> 83
109 endif 84 endif
110 85
111 else 86 else
112 87
113 # set src + obj - they may be used in the modu 88 # set src + obj - they may be used in the modules's Makefile
114 obj := $(KBUILD_EXTMOD) 89 obj := $(KBUILD_EXTMOD)
115 src := $(if $(VPATH),$(VPATH)/)$(obj) !! 90 src := $(obj)
116 91
117 # Include the module's Makefile to find KBUILD 92 # Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS
118 include $(kbuild-file) !! 93 include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \
>> 94 $(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile)
>> 95
>> 96 # modpost option for external modules
>> 97 MODPOST += -e
119 98
>> 99 input-symdump := Module.symvers $(KBUILD_EXTRA_SYMBOLS)
120 output-symdump := $(KBUILD_EXTMOD)/Module.symv 100 output-symdump := $(KBUILD_EXTMOD)/Module.symvers
121 101
122 ifeq ($(wildcard Module.symvers),) <<
123 missing-input := Module.symvers <<
124 else <<
125 modpost-args += -i Module.symvers <<
126 modpost-deps += Module.symvers <<
127 endif 102 endif
128 103
129 modpost-args += -e $(addprefix -i , $(KBUILD_E !! 104 # modpost options for modules (both in-kernel and external)
>> 105 MODPOST += \
>> 106 $(addprefix -i ,$(wildcard $(input-symdump))) \
>> 107 $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \
>> 108 $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N)
>> 109
>> 110 # 'make -i -k' ignores compile errors, and builds as many modules as possible.
>> 111 ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),)
>> 112 MODPOST += -n
>> 113 endif
>> 114
>> 115 # Clear VPATH to not search for *.symvers in $(srctree). Check only $(objtree).
>> 116 VPATH :=
>> 117 $(input-symdump):
>> 118 @echo >&2 'WARNING: Symbol version dump "$@" is missing.'
>> 119 @echo >&2 ' Modules may not have dependencies or modversions.'
>> 120
>> 121 ifdef CONFIG_LTO_CLANG
>> 122 # With CONFIG_LTO_CLANG, .o files might be LLVM bitcode, so we need to run
>> 123 # LTO to compile them into native code before running modpost
>> 124 prelink-ext := .lto
>> 125
>> 126 quiet_cmd_cc_lto_link_modules = LTO [M] $@
>> 127 cmd_cc_lto_link_modules = \
>> 128 $(LD) $(ld_flags) -r -o $@ \
>> 129 $(shell [ -s $(@:.lto.o=.o.symversions) ] && \
>> 130 echo -T $(@:.lto.o=.o.symversions)) \
>> 131 --whole-archive $^
>> 132
>> 133 %.lto.o: %.o
>> 134 $(call if_changed,cc_lto_link_modules)
>> 135 endif
130 136
131 endif # ($(KBUILD_EXTMOD),) !! 137 modules := $(sort $(shell cat $(MODORDER)))
132 138
>> 139 # Read out modules.order to pass in modpost.
>> 140 # Otherwise, allmodconfig would fail with "Argument list too long".
133 quiet_cmd_modpost = MODPOST $@ 141 quiet_cmd_modpost = MODPOST $@
134 cmd_modpost = \ !! 142 cmd_modpost = sed 's/\.ko$$/$(prelink-ext)\.o/' $< | $(MODPOST) -T -
135 $(if $(missing-input), \ <<
136 echo >&2 "WARNING: $(missing-i <<
137 echo >&2 " Modules may <<
138 echo >&2 " You may get <<
139 echo >&2 " You can set <<
140 echo >&2 " if you want <<
141 $(MODPOST) $(modpost-args) <<
142 143
143 targets += $(output-symdump) !! 144 $(output-symdump): $(MODORDER) $(input-symdump) $(modules:.ko=$(prelink-ext).o) FORCE
144 $(output-symdump): $(modpost-deps) FORCE <<
145 $(call if_changed,modpost) 145 $(call if_changed,modpost)
146 146
>> 147 targets += $(output-symdump)
>> 148
147 __modpost: $(output-symdump) 149 __modpost: $(output-symdump)
>> 150 ifneq ($(KBUILD_MODPOST_NOFINAL),1)
>> 151 $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
>> 152 endif
>> 153
148 PHONY += FORCE 154 PHONY += FORCE
149 FORCE: 155 FORCE:
150 156
151 existing-targets := $(wildcard $(sort $(target 157 existing-targets := $(wildcard $(sort $(targets)))
152 158
153 -include $(foreach f,$(existing-targets),$(dir 159 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
>> 160
>> 161 endif
154 162
155 .PHONY: $(PHONY) 163 .PHONY: $(PHONY)
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