1 # ==========================================================================
3 # ==========================================================================
10 # Init all relevant variables used in kbuild files so
11 # 1) they have correct type
12 # 2) they do not inherit any value from the environment
33 # Read auto.conf if it exists, otherwise ignore
34 -include include/config/auto.conf
36 include scripts/Kbuild.include
38 # For backward compatibility check that these variables do not change
39 save-cflags := $(CFLAGS)
41 # The filename Kbuild has precedence over Makefile
42 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
43 kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
44 include $(kbuild-file)
46 # If the save-* variables changed error out
47 ifeq ($(KBUILD_NOPEDANTIC),)
48 ifneq ("$(save-cflags)","$(CFLAGS)")
49 $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
53 include scripts/Makefile.lib
56 ifneq ($(hostprogs-y),$(host-progs))
57 $(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
58 hostprogs-y += $(host-progs)
62 # Do not include host rules unless needed
63 ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
64 include scripts/Makefile.host
67 ifneq ($(KBUILD_SRC),)
68 # Create output directory if not already present
69 _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
71 # Create directories for object files if directory does not exist
72 # Needed when obj-y := dir/file.o syntax is used
73 _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
77 $(warning kbuild: Makefile.build is included improperly)
80 # ===========================================================================
82 ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
83 lib-target := $(obj)/lib.a
84 obj-y += $(obj)/lib-ksyms.o
87 ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
88 builtin-target := $(obj)/built-in.o
91 modorder-target := $(obj)/modules.order
93 # We keep a list of all modules in $(MODVERDIR)
95 __build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
96 $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
97 $(subdir-ym) $(always)
100 # Linus' kernel sanity checking tool
101 ifneq ($(KBUILD_CHECKSRC),0)
102 ifeq ($(KBUILD_CHECKSRC),2)
103 quiet_cmd_force_checksrc = CHECK $<
104 cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
106 quiet_cmd_checksrc = CHECK $<
107 cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
111 # Do section mismatch analysis for each module/built-in.o
112 ifdef CONFIG_DEBUG_SECTION_MISMATCH
113 cmd_secanalysis = ; scripts/mod/modpost $@
116 # Compile C sources (.c)
117 # ---------------------------------------------------------------------------
119 # Default is built-in, unless we know otherwise
121 $(if $(part-of-module), \
122 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
123 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
124 quiet_modtag := $(empty) $(empty)
126 $(real-objs-m) : part-of-module := y
127 $(real-objs-m:.o=.i) : part-of-module := y
128 $(real-objs-m:.o=.s) : part-of-module := y
129 $(real-objs-m:.o=.lst): part-of-module := y
131 $(real-objs-m) : quiet_modtag := [M]
132 $(real-objs-m:.o=.i) : quiet_modtag := [M]
133 $(real-objs-m:.o=.s) : quiet_modtag := [M]
134 $(real-objs-m:.o=.lst): quiet_modtag := [M]
136 $(obj-m) : quiet_modtag := [M]
138 # Default for not multi-part modules
139 modname = $(basetarget)
141 $(multi-objs-m) : modname = $(modname-multi)
142 $(multi-objs-m:.o=.i) : modname = $(modname-multi)
143 $(multi-objs-m:.o=.s) : modname = $(modname-multi)
144 $(multi-objs-m:.o=.lst) : modname = $(modname-multi)
145 $(multi-objs-y) : modname = $(modname-multi)
146 $(multi-objs-y:.o=.i) : modname = $(modname-multi)
147 $(multi-objs-y:.o=.s) : modname = $(modname-multi)
148 $(multi-objs-y:.o=.lst) : modname = $(modname-multi)
150 quiet_cmd_cc_s_c = CC $(quiet_modtag) $@
151 cmd_cc_s_c = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
153 $(obj)/%.s: $(src)/%.c FORCE
154 $(call if_changed_dep,cc_s_c)
156 quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@
157 cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $<
159 $(obj)/%.i: $(src)/%.c FORCE
160 $(call if_changed_dep,cpp_i_c)
162 # These mirror gensymtypes_S and co below, keep them in synch.
163 cmd_gensymtypes_c = \
164 $(CPP) -D__GENKSYMS__ $(c_flags) $< | \
165 $(GENKSYMS) $(if $(1), -T $(2)) \
166 $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX)) \
167 $(if $(KBUILD_PRESERVE),-p) \
168 -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
170 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
171 cmd_cc_symtypes_c = \
173 $(call cmd_gensymtypes_c,true,$@) >/dev/null; \
174 test -s $@ || rm -f $@
176 $(obj)/%.symtypes : $(src)/%.c FORCE
177 $(call cmd,cc_symtypes_c)
180 # The C file is compiled and updated dependency information is generated.
181 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
183 quiet_cmd_cc_o_c = CC $(quiet_modtag) $@
185 ifndef CONFIG_MODVERSIONS
186 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
189 # When module versioning is enabled the following steps are executed:
190 # o compile a .tmp_<file>.o from <file>.c
191 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
192 # not export symbols, we just rename .tmp_<file>.o to <file>.o and
194 # o otherwise, we calculate symbol versions using the good old
195 # genksyms on the preprocessed source and postprocess them in a way
196 # that they are usable as a linker script
197 # o generate <file>.o from .tmp_<file>.o using the linker to
198 # replace the unresolved symbols __crc_exported_symbol with
199 # the actual value of the checksum generated by genksyms
201 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
203 cmd_modversions_c = \
204 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
205 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \
206 > $(@D)/.tmp_$(@F:.o=.ver); \
208 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
209 -T $(@D)/.tmp_$(@F:.o=.ver); \
210 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
212 mv -f $(@D)/.tmp_$(@F) $@; \
216 ifdef CONFIG_FTRACE_MCOUNT_RECORD
217 ifdef BUILD_C_RECORDMCOUNT
218 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
219 RECORDMCOUNT_FLAGS = -w
221 # Due to recursion, we must skip empty.o.
222 # The empty.o file is created in the make process in order to determine
223 # the target endianness and word size. It is made before all other C
224 # files, including recordmcount.
225 sub_cmd_record_mcount = \
226 if [ $(@) != "scripts/mod/empty.o" ]; then \
227 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \
229 recordmcount_source := $(srctree)/scripts/recordmcount.c \
230 $(srctree)/scripts/recordmcount.h
232 sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
233 "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
234 "$(if $(CONFIG_64BIT),64,32)" \
235 "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
236 "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
237 "$(if $(part-of-module),1,0)" "$(@)";
238 recordmcount_source := $(srctree)/scripts/recordmcount.pl
240 cmd_record_mcount = \
241 if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" = \
242 "$(CC_FLAGS_FTRACE)" ]; then \
243 $(sub_cmd_record_mcount) \
247 ifdef CONFIG_STACK_VALIDATION
248 ifneq ($(SKIP_STACK_VALIDATION),1)
250 __objtool_obj := $(objtree)/tools/objtool/objtool
253 ifndef CONFIG_FRAME_POINTER
254 objtool_args += --no-fp
257 # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
258 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
259 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
260 cmd_objtool = $(if $(patsubst y%,, \
261 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
262 $(__objtool_obj) $(objtool_args) "$(@)";)
263 objtool_obj = $(if $(patsubst y%,, \
264 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
267 endif # SKIP_STACK_VALIDATION
268 endif # CONFIG_STACK_VALIDATION
271 $(call echo-cmd,checksrc) $(cmd_checksrc) \
272 $(call cmd_and_fixdep,cc_o_c) \
273 $(cmd_modversions_c) \
275 $(call echo-cmd,record_mcount) $(cmd_record_mcount)
279 $(call cmd_and_fixdep,as_o_S) \
280 $(cmd_modversions_S) \
284 # List module undefined symbols (or empty line if not enabled)
285 ifdef CONFIG_TRIM_UNUSED_KSYMS
286 cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo
288 cmd_undef_syms = echo
291 # Built-in and composite module parts
292 $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
293 $(call cmd,force_checksrc)
294 $(call if_changed_rule,cc_o_c)
296 # Single-part modules are special since we need to mark them in $(MODVERDIR)
298 $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
299 $(call cmd,force_checksrc)
300 $(call if_changed_rule,cc_o_c)
301 @{ echo $(@:.o=.ko); echo $@; \
302 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
304 quiet_cmd_cc_lst_c = MKLST $@
305 cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
306 $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
307 System.map $(OBJDUMP) > $@
309 $(obj)/%.lst: $(src)/%.c FORCE
310 $(call if_changed_dep,cc_lst_c)
312 # Compile assembler sources (.S)
313 # ---------------------------------------------------------------------------
315 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
317 $(real-objs-m) : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
318 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
320 # .S file exports must have their C prototypes defined in asm/asm-prototypes.h
321 # or a file that it includes, in order to get versioned symbols. We build a
322 # dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
323 # the .S file (with trailing ';'), and run genksyms on that, to extract vers.
325 # This is convoluted. The .S file must first be preprocessed to run guards and
326 # expand names, then the resulting exports must be constructed into plain
327 # EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
328 # to make the genksyms input.
330 # These mirror gensymtypes_c and co above, keep them in synch.
331 cmd_gensymtypes_S = \
332 (echo "\#include <linux/kernel.h>" ; \
333 echo "\#include <asm/asm-prototypes.h>" ; \
334 $(CPP) $(a_flags) $< | \
335 grep "\<___EXPORT_SYMBOL\>" | \
336 sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
337 $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | \
338 $(GENKSYMS) $(if $(1), -T $(2)) \
339 $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX)) \
340 $(if $(KBUILD_PRESERVE),-p) \
341 -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
343 quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
344 cmd_cc_symtypes_S = \
346 $(call cmd_gensymtypes_S,true,$@) >/dev/null; \
347 test -s $@ || rm -f $@
349 $(obj)/%.symtypes : $(src)/%.S FORCE
350 $(call cmd,cc_symtypes_S)
353 quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
354 cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $<
356 $(obj)/%.s: $(src)/%.S FORCE
357 $(call if_changed_dep,cpp_s_S)
359 quiet_cmd_as_o_S = AS $(quiet_modtag) $@
361 ifndef CONFIG_MODVERSIONS
362 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
366 ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
368 ifeq ($(ASM_PROTOTYPES),)
369 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
373 # versioning matches the C process described above, with difference that
374 # we parse asm-prototypes.h C header to get function definitions.
376 cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
378 cmd_modversions_S = \
379 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
380 $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \
381 > $(@D)/.tmp_$(@F:.o=.ver); \
383 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
384 -T $(@D)/.tmp_$(@F:.o=.ver); \
385 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
387 mv -f $(@D)/.tmp_$(@F) $@; \
392 $(obj)/%.o: $(src)/%.S $(objtool_obj) FORCE
393 $(call if_changed_rule,as_o_S)
395 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
396 targets += $(extra-y) $(MAKECMDGOALS) $(always)
398 # Linker scripts preprocessor (.lds.S -> .lds)
399 # ---------------------------------------------------------------------------
400 quiet_cmd_cpp_lds_S = LDS $@
401 cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
402 -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
404 $(obj)/%.lds: $(src)/%.lds.S FORCE
405 $(call if_changed_dep,cpp_lds_S)
408 # ---------------------------------------------------------------------------
409 quiet_cmd_asn1_compiler = ASN.1 $@
410 cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
411 $(subst .h,.c,$@) $(subst .c,.h,$@)
413 .PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
415 $(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
416 $(call cmd,asn1_compiler)
418 # Build the compiled-in targets
419 # ---------------------------------------------------------------------------
421 # To build objects in subdirs, we need to descend into the directories
422 $(sort $(subdir-obj-y)): $(subdir-ym) ;
425 # Rule to compile a set of .o files into one .o file
429 ifdef CONFIG_THIN_ARCHIVES
430 cmd_make_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS)
431 cmd_make_empty_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS)
432 quiet_cmd_link_o_target = AR $@
434 cmd_make_builtin = $(LD) $(ld_flags) -r -o
435 cmd_make_empty_builtin = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS)
436 quiet_cmd_link_o_target = LD $@
439 # If the list of objects to link is empty, just create an empty built-in.o
440 cmd_link_o_target = $(if $(strip $(obj-y)),\
441 $(cmd_make_builtin) $@ $(filter $(obj-y), $^) \
443 $(cmd_make_empty_builtin) $@)
445 $(builtin-target): $(obj-y) FORCE
446 $(call if_changed,link_o_target)
448 targets += $(builtin-target)
449 endif # builtin-target
452 # Rule to create modules.order file
454 # Create commands to either record .ko file or cat modules.order from
457 $(foreach m, $(modorder), \
458 $(if $(filter %/modules.order, $m), \
459 cat $m;, echo kernel/$m;))
461 $(modorder-target): $(subdir-ym) FORCE
462 $(Q)(cat /dev/null; $(modorder-cmds)) > $@
465 # Rule to compile a set of .o files into one .a file
468 quiet_cmd_link_l_target = AR $@
470 ifdef CONFIG_THIN_ARCHIVES
471 cmd_link_l_target = rm -f $@; $(AR) rcsT$(KBUILD_ARFLAGS) $@ $(lib-y)
473 cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
476 $(lib-target): $(lib-y) FORCE
477 $(call if_changed,link_l_target)
479 targets += $(lib-target)
481 dummy-object = $(obj)/.lib_exports.o
482 ksyms-lds = $(dot-target).lds
483 ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
484 ref_prefix = EXTERN(_
489 quiet_cmd_export_list = EXPORTS $@
490 cmd_export_list = $(OBJDUMP) -h $< | \
491 sed -ne '/___ksymtab/s/.*+\([^ ]*\).*/$(ref_prefix)\1)/p' >$(ksyms-lds);\
492 rm -f $(dummy-object);\
493 echo | $(CC) $(a_flags) -c -o $(dummy-object) -x assembler -;\
494 $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\
495 rm $(dummy-object) $(ksyms-lds)
497 $(obj)/lib-ksyms.o: $(lib-target) FORCE
498 $(call if_changed,export_list)
500 targets += $(obj)/lib-ksyms.o
505 # Rule to link composite objects
507 # Composite objects are specified in kbuild makefile as follows:
508 # <composite-object>-objs := <list of .o files>
510 # <composite-object>-y := <list of .o files>
512 # <composite-object>-m := <list of .o files>
513 # The -m syntax only works if <composite object> is a module
515 $(filter $(addprefix $(obj)/, \
516 $($(subst $(obj)/,,$(@:.o=-objs))) \
517 $($(subst $(obj)/,,$(@:.o=-y))) \
518 $($(subst $(obj)/,,$(@:.o=-m)))), $^)
520 cmd_link_multi-link = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
522 ifdef CONFIG_THIN_ARCHIVES
523 quiet_cmd_link_multi-y = AR $@
524 cmd_link_multi-y = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS) $@ $(link_multi_deps)
526 quiet_cmd_link_multi-y = LD $@
527 cmd_link_multi-y = $(cmd_link_multi-link)
530 quiet_cmd_link_multi-m = LD [M] $@
531 cmd_link_multi-m = $(cmd_link_multi-link)
533 $(multi-used-y): FORCE
534 $(call if_changed,link_multi-y)
535 $(call multi_depend, $(multi-used-y), .o, -objs -y)
537 $(multi-used-m): FORCE
538 $(call if_changed,link_multi-m)
539 @{ echo $(@:.o=.ko); echo $(link_multi_deps); \
540 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
541 $(call multi_depend, $(multi-used-m), .o, -objs -y -m)
543 targets += $(multi-used-y) $(multi-used-m)
547 # ---------------------------------------------------------------------------
549 PHONY += $(subdir-ym)
551 $(Q)$(MAKE) $(build)=$@
553 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
554 # ---------------------------------------------------------------------------
560 # Read all saved command lines and dependencies for the $(targets) we
561 # may be building above, using $(if_changed{,_dep}). As an
562 # optimization, we don't need to read them if the target does not
563 # exist, we will rebuild anyway in that case.
565 targets := $(wildcard $(sort $(targets)))
566 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
568 ifneq ($(cmd_files),)
572 # Declare the contents of the .PHONY variable as phony. We keep that
573 # information in a variable se we can use it in if_changed and friends.