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 # Generate .ll files from .c
181 quiet_cmd_cc_ll_c = CC $(quiet_modtag) $@
182 cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $<
184 $(obj)/%.ll: $(src)/%.c FORCE
185 $(call if_changed_dep,cc_ll_c)
188 # The C file is compiled and updated dependency information is generated.
189 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
191 quiet_cmd_cc_o_c = CC $(quiet_modtag) $@
193 ifndef CONFIG_MODVERSIONS
194 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
197 # When module versioning is enabled the following steps are executed:
198 # o compile a .tmp_<file>.o from <file>.c
199 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
200 # not export symbols, we just rename .tmp_<file>.o to <file>.o and
202 # o otherwise, we calculate symbol versions using the good old
203 # genksyms on the preprocessed source and postprocess them in a way
204 # that they are usable as a linker script
205 # o generate <file>.o from .tmp_<file>.o using the linker to
206 # replace the unresolved symbols __crc_exported_symbol with
207 # the actual value of the checksum generated by genksyms
209 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
211 cmd_modversions_c = \
212 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
213 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \
214 > $(@D)/.tmp_$(@F:.o=.ver); \
216 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
217 -T $(@D)/.tmp_$(@F:.o=.ver); \
218 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
220 mv -f $(@D)/.tmp_$(@F) $@; \
224 ifdef CONFIG_FTRACE_MCOUNT_RECORD
225 ifndef CC_USING_RECORD_MCOUNT
226 # compiler will not generate __mcount_loc use recordmcount or recordmcount.pl
227 ifdef BUILD_C_RECORDMCOUNT
228 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
229 RECORDMCOUNT_FLAGS = -w
231 # Due to recursion, we must skip empty.o.
232 # The empty.o file is created in the make process in order to determine
233 # the target endianness and word size. It is made before all other C
234 # files, including recordmcount.
235 sub_cmd_record_mcount = \
236 if [ $(@) != "scripts/mod/empty.o" ]; then \
237 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \
239 recordmcount_source := $(srctree)/scripts/recordmcount.c \
240 $(srctree)/scripts/recordmcount.h
242 sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
243 "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
244 "$(if $(CONFIG_64BIT),64,32)" \
245 "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
246 "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
247 "$(if $(part-of-module),1,0)" "$(@)";
248 recordmcount_source := $(srctree)/scripts/recordmcount.pl
250 cmd_record_mcount = \
251 if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" = \
252 "$(CC_FLAGS_FTRACE)" ]; then \
253 $(sub_cmd_record_mcount) \
255 endif # CC_USING_RECORD_MCOUNT
258 ifdef CONFIG_STACK_VALIDATION
259 ifneq ($(SKIP_STACK_VALIDATION),1)
261 __objtool_obj := $(objtree)/tools/objtool/objtool
264 ifndef CONFIG_FRAME_POINTER
265 objtool_args += --no-fp
267 ifdef CONFIG_GCOV_KERNEL
268 objtool_args += --no-unreachable
271 # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
272 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
273 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
274 cmd_objtool = $(if $(patsubst y%,, \
275 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
276 $(__objtool_obj) $(objtool_args) "$(@)";)
277 objtool_obj = $(if $(patsubst y%,, \
278 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
281 endif # SKIP_STACK_VALIDATION
282 endif # CONFIG_STACK_VALIDATION
285 $(call echo-cmd,checksrc) $(cmd_checksrc) \
286 $(call cmd_and_fixdep,cc_o_c) \
287 $(cmd_modversions_c) \
289 $(call echo-cmd,record_mcount) $(cmd_record_mcount)
293 $(call cmd_and_fixdep,as_o_S) \
294 $(cmd_modversions_S) \
298 # List module undefined symbols (or empty line if not enabled)
299 ifdef CONFIG_TRIM_UNUSED_KSYMS
300 cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo
302 cmd_undef_syms = echo
305 # Built-in and composite module parts
306 $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
307 $(call cmd,force_checksrc)
308 $(call if_changed_rule,cc_o_c)
310 # Single-part modules are special since we need to mark them in $(MODVERDIR)
312 $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
313 $(call cmd,force_checksrc)
314 $(call if_changed_rule,cc_o_c)
315 @{ echo $(@:.o=.ko); echo $@; \
316 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
318 quiet_cmd_cc_lst_c = MKLST $@
319 cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
320 $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
321 System.map $(OBJDUMP) > $@
323 $(obj)/%.lst: $(src)/%.c FORCE
324 $(call if_changed_dep,cc_lst_c)
326 # Compile assembler sources (.S)
327 # ---------------------------------------------------------------------------
329 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
331 $(real-objs-m) : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
332 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
334 # .S file exports must have their C prototypes defined in asm/asm-prototypes.h
335 # or a file that it includes, in order to get versioned symbols. We build a
336 # dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
337 # the .S file (with trailing ';'), and run genksyms on that, to extract vers.
339 # This is convoluted. The .S file must first be preprocessed to run guards and
340 # expand names, then the resulting exports must be constructed into plain
341 # EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
342 # to make the genksyms input.
344 # These mirror gensymtypes_c and co above, keep them in synch.
345 cmd_gensymtypes_S = \
346 (echo "\#include <linux/kernel.h>" ; \
347 echo "\#include <asm/asm-prototypes.h>" ; \
348 $(CPP) $(a_flags) $< | \
349 grep "\<___EXPORT_SYMBOL\>" | \
350 sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
351 $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | \
352 $(GENKSYMS) $(if $(1), -T $(2)) \
353 $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX)) \
354 $(if $(KBUILD_PRESERVE),-p) \
355 -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
357 quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
358 cmd_cc_symtypes_S = \
360 $(call cmd_gensymtypes_S,true,$@) >/dev/null; \
361 test -s $@ || rm -f $@
363 $(obj)/%.symtypes : $(src)/%.S FORCE
364 $(call cmd,cc_symtypes_S)
367 quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
368 cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $<
370 $(obj)/%.s: $(src)/%.S FORCE
371 $(call if_changed_dep,cpp_s_S)
373 quiet_cmd_as_o_S = AS $(quiet_modtag) $@
375 ifndef CONFIG_MODVERSIONS
376 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
380 ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
382 ifeq ($(ASM_PROTOTYPES),)
383 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
387 # versioning matches the C process described above, with difference that
388 # we parse asm-prototypes.h C header to get function definitions.
390 cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
392 cmd_modversions_S = \
393 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
394 $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \
395 > $(@D)/.tmp_$(@F:.o=.ver); \
397 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
398 -T $(@D)/.tmp_$(@F:.o=.ver); \
399 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
401 mv -f $(@D)/.tmp_$(@F) $@; \
406 $(obj)/%.o: $(src)/%.S $(objtool_obj) FORCE
407 $(call if_changed_rule,as_o_S)
409 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
410 targets += $(extra-y) $(MAKECMDGOALS) $(always)
412 # Linker scripts preprocessor (.lds.S -> .lds)
413 # ---------------------------------------------------------------------------
414 quiet_cmd_cpp_lds_S = LDS $@
415 cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
416 -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
418 $(obj)/%.lds: $(src)/%.lds.S FORCE
419 $(call if_changed_dep,cpp_lds_S)
422 # ---------------------------------------------------------------------------
423 quiet_cmd_asn1_compiler = ASN.1 $@
424 cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
425 $(subst .h,.c,$@) $(subst .c,.h,$@)
427 .PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
429 $(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
430 $(call cmd,asn1_compiler)
432 # Build the compiled-in targets
433 # ---------------------------------------------------------------------------
435 # To build objects in subdirs, we need to descend into the directories
436 $(sort $(subdir-obj-y)): $(subdir-ym) ;
439 # Rule to compile a set of .o files into one .o file
443 ifdef CONFIG_THIN_ARCHIVES
444 cmd_make_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS)
445 cmd_make_empty_builtin = rm -f $@; $(AR) rcST$(KBUILD_ARFLAGS)
446 quiet_cmd_link_o_target = AR $@
448 cmd_make_builtin = $(LD) $(ld_flags) -r -o
449 cmd_make_empty_builtin = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS)
450 quiet_cmd_link_o_target = LD $@
453 # If the list of objects to link is empty, just create an empty built-in.o
454 cmd_link_o_target = $(if $(strip $(obj-y)),\
455 $(cmd_make_builtin) $@ $(filter $(obj-y), $^) \
457 $(cmd_make_empty_builtin) $@)
459 $(builtin-target): $(obj-y) FORCE
460 $(call if_changed,link_o_target)
462 targets += $(builtin-target)
463 endif # builtin-target
466 # Rule to create modules.order file
468 # Create commands to either record .ko file or cat modules.order from
471 $(foreach m, $(modorder), \
472 $(if $(filter %/modules.order, $m), \
473 cat $m;, echo kernel/$m;))
475 $(modorder-target): $(subdir-ym) FORCE
476 $(Q)(cat /dev/null; $(modorder-cmds)) > $@
479 # Rule to compile a set of .o files into one .a file
482 quiet_cmd_link_l_target = AR $@
484 ifdef CONFIG_THIN_ARCHIVES
485 cmd_link_l_target = rm -f $@; $(AR) rcsT$(KBUILD_ARFLAGS) $@ $(lib-y)
487 cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
490 $(lib-target): $(lib-y) FORCE
491 $(call if_changed,link_l_target)
493 targets += $(lib-target)
495 dummy-object = $(obj)/.lib_exports.o
496 ksyms-lds = $(dot-target).lds
497 ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
498 ref_prefix = EXTERN(_
503 quiet_cmd_export_list = EXPORTS $@
504 cmd_export_list = $(OBJDUMP) -h $< | \
505 sed -ne '/___ksymtab/{s/.*+/$(ref_prefix)/;s/ .*/)/;p}' >$(ksyms-lds);\
506 rm -f $(dummy-object);\
507 $(AR) rcs$(KBUILD_ARFLAGS) $(dummy-object);\
508 $(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\
509 rm $(dummy-object) $(ksyms-lds)
511 $(obj)/lib-ksyms.o: $(lib-target) FORCE
512 $(call if_changed,export_list)
514 targets += $(obj)/lib-ksyms.o
519 # Rule to link composite objects
521 # Composite objects are specified in kbuild makefile as follows:
522 # <composite-object>-objs := <list of .o files>
524 # <composite-object>-y := <list of .o files>
526 # <composite-object>-m := <list of .o files>
527 # The -m syntax only works if <composite object> is a module
529 $(filter $(addprefix $(obj)/, \
530 $($(subst $(obj)/,,$(@:.o=-objs))) \
531 $($(subst $(obj)/,,$(@:.o=-y))) \
532 $($(subst $(obj)/,,$(@:.o=-m)))), $^)
534 quiet_cmd_link_multi-y = LD $@
535 cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
537 quiet_cmd_link_multi-m = LD [M] $@
538 cmd_link_multi-m = $(cmd_link_multi-y)
540 $(multi-used-y): FORCE
541 $(call if_changed,link_multi-y)
542 $(call multi_depend, $(multi-used-y), .o, -objs -y)
544 $(multi-used-m): FORCE
545 $(call if_changed,link_multi-m)
546 @{ echo $(@:.o=.ko); echo $(link_multi_deps); \
547 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
548 $(call multi_depend, $(multi-used-m), .o, -objs -y -m)
550 targets += $(multi-used-y) $(multi-used-m)
554 # ---------------------------------------------------------------------------
556 PHONY += $(subdir-ym)
558 $(Q)$(MAKE) $(build)=$@
560 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
561 # ---------------------------------------------------------------------------
567 # Read all saved command lines and dependencies for the $(targets) we
568 # may be building above, using $(if_changed{,_dep}). As an
569 # optimization, we don't need to read them if the target does not
570 # exist, we will rebuild anyway in that case.
572 targets := $(wildcard $(sort $(targets)))
573 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
575 ifneq ($(cmd_files),)
579 # Declare the contents of the .PHONY variable as phony. We keep that
580 # information in a variable se we can use it in if_changed and friends.