Makefile 51 KB

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  1. VERSION = 2
  2. PATCHLEVEL = 6
  3. SUBLEVEL = 37
  4. EXTRAVERSION = -rc1
  5. NAME = Flesh-Eating Bats with Fangs
  6. # *DOCUMENTATION*
  7. # To see a list of typical targets execute "make help"
  8. # More info can be located in ./README
  9. # Comments in this file are targeted only to the developer, do not
  10. # expect to learn how to build the kernel reading this file.
  11. # Do not:
  12. # o use make's built-in rules and variables
  13. # (this increases performance and avoids hard-to-debug behaviour);
  14. # o print "Entering directory ...";
  15. MAKEFLAGS += -rR --no-print-directory
  16. # Avoid funny character set dependencies
  17. unexport LC_ALL
  18. LC_COLLATE=C
  19. LC_NUMERIC=C
  20. export LC_COLLATE LC_NUMERIC
  21. # We are using a recursive build, so we need to do a little thinking
  22. # to get the ordering right.
  23. #
  24. # Most importantly: sub-Makefiles should only ever modify files in
  25. # their own directory. If in some directory we have a dependency on
  26. # a file in another dir (which doesn't happen often, but it's often
  27. # unavoidable when linking the built-in.o targets which finally
  28. # turn into vmlinux), we will call a sub make in that other dir, and
  29. # after that we are sure that everything which is in that other dir
  30. # is now up to date.
  31. #
  32. # The only cases where we need to modify files which have global
  33. # effects are thus separated out and done before the recursive
  34. # descending is started. They are now explicitly listed as the
  35. # prepare rule.
  36. # To put more focus on warnings, be less verbose as default
  37. # Use 'make V=1' to see the full commands
  38. ifeq ("$(origin V)", "command line")
  39. KBUILD_VERBOSE = $(V)
  40. endif
  41. ifndef KBUILD_VERBOSE
  42. KBUILD_VERBOSE = 0
  43. endif
  44. # Call a source code checker (by default, "sparse") as part of the
  45. # C compilation.
  46. #
  47. # Use 'make C=1' to enable checking of only re-compiled files.
  48. # Use 'make C=2' to enable checking of *all* source files, regardless
  49. # of whether they are re-compiled or not.
  50. #
  51. # See the file "Documentation/sparse.txt" for more details, including
  52. # where to get the "sparse" utility.
  53. ifeq ("$(origin C)", "command line")
  54. KBUILD_CHECKSRC = $(C)
  55. endif
  56. ifndef KBUILD_CHECKSRC
  57. KBUILD_CHECKSRC = 0
  58. endif
  59. # Use make M=dir to specify directory of external module to build
  60. # Old syntax make ... SUBDIRS=$PWD is still supported
  61. # Setting the environment variable KBUILD_EXTMOD take precedence
  62. ifdef SUBDIRS
  63. KBUILD_EXTMOD ?= $(SUBDIRS)
  64. endif
  65. ifeq ("$(origin M)", "command line")
  66. KBUILD_EXTMOD := $(M)
  67. endif
  68. # kbuild supports saving output files in a separate directory.
  69. # To locate output files in a separate directory two syntaxes are supported.
  70. # In both cases the working directory must be the root of the kernel src.
  71. # 1) O=
  72. # Use "make O=dir/to/store/output/files/"
  73. #
  74. # 2) Set KBUILD_OUTPUT
  75. # Set the environment variable KBUILD_OUTPUT to point to the directory
  76. # where the output files shall be placed.
  77. # export KBUILD_OUTPUT=dir/to/store/output/files/
  78. # make
  79. #
  80. # The O= assignment takes precedence over the KBUILD_OUTPUT environment
  81. # variable.
  82. # KBUILD_SRC is set on invocation of make in OBJ directory
  83. # KBUILD_SRC is not intended to be used by the regular user (for now)
  84. ifeq ($(KBUILD_SRC),)
  85. # OK, Make called in directory where kernel src resides
  86. # Do we want to locate output files in a separate directory?
  87. ifeq ("$(origin O)", "command line")
  88. KBUILD_OUTPUT := $(O)
  89. endif
  90. # That's our default target when none is given on the command line
  91. PHONY := _all
  92. _all:
  93. # Cancel implicit rules on top Makefile
  94. $(CURDIR)/Makefile Makefile: ;
  95. ifneq ($(KBUILD_OUTPUT),)
  96. # Invoke a second make in the output directory, passing relevant variables
  97. # check that the output directory actually exists
  98. saved-output := $(KBUILD_OUTPUT)
  99. KBUILD_OUTPUT := $(shell cd $(KBUILD_OUTPUT) && /bin/pwd)
  100. $(if $(KBUILD_OUTPUT),, \
  101. $(error output directory "$(saved-output)" does not exist))
  102. PHONY += $(MAKECMDGOALS) sub-make
  103. $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
  104. $(Q)@:
  105. sub-make: FORCE
  106. $(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
  107. KBUILD_SRC=$(CURDIR) \
  108. KBUILD_EXTMOD="$(KBUILD_EXTMOD)" -f $(CURDIR)/Makefile \
  109. $(filter-out _all sub-make,$(MAKECMDGOALS))
  110. # Leave processing to above invocation of make
  111. skip-makefile := 1
  112. endif # ifneq ($(KBUILD_OUTPUT),)
  113. endif # ifeq ($(KBUILD_SRC),)
  114. # We process the rest of the Makefile if this is the final invocation of make
  115. ifeq ($(skip-makefile),)
  116. # If building an external module we do not care about the all: rule
  117. # but instead _all depend on modules
  118. PHONY += all
  119. ifeq ($(KBUILD_EXTMOD),)
  120. _all: all
  121. else
  122. _all: modules
  123. endif
  124. srctree := $(if $(KBUILD_SRC),$(KBUILD_SRC),$(CURDIR))
  125. objtree := $(CURDIR)
  126. src := $(srctree)
  127. obj := $(objtree)
  128. VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
  129. export srctree objtree VPATH
  130. # SUBARCH tells the usermode build what the underlying arch is. That is set
  131. # first, and if a usermode build is happening, the "ARCH=um" on the command
  132. # line overrides the setting of ARCH below. If a native build is happening,
  133. # then ARCH is assigned, getting whatever value it gets normally, and
  134. # SUBARCH is subsequently ignored.
  135. SUBARCH := $(shell uname -m | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
  136. -e s/arm.*/arm/ -e s/sa110/arm/ \
  137. -e s/s390x/s390/ -e s/parisc64/parisc/ \
  138. -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
  139. -e s/sh[234].*/sh/ )
  140. # Cross compiling and selecting different set of gcc/bin-utils
  141. # ---------------------------------------------------------------------------
  142. #
  143. # When performing cross compilation for other architectures ARCH shall be set
  144. # to the target architecture. (See arch/* for the possibilities).
  145. # ARCH can be set during invocation of make:
  146. # make ARCH=ia64
  147. # Another way is to have ARCH set in the environment.
  148. # The default ARCH is the host where make is executed.
  149. # CROSS_COMPILE specify the prefix used for all executables used
  150. # during compilation. Only gcc and related bin-utils executables
  151. # are prefixed with $(CROSS_COMPILE).
  152. # CROSS_COMPILE can be set on the command line
  153. # make CROSS_COMPILE=ia64-linux-
  154. # Alternatively CROSS_COMPILE can be set in the environment.
  155. # A third alternative is to store a setting in .config so that plain
  156. # "make" in the configured kernel build directory always uses that.
  157. # Default value for CROSS_COMPILE is not to prefix executables
  158. # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
  159. export KBUILD_BUILDHOST := $(SUBARCH)
  160. ARCH ?= $(SUBARCH)
  161. CROSS_COMPILE ?= $(CONFIG_CROSS_COMPILE:"%"=%)
  162. # Architecture as present in compile.h
  163. UTS_MACHINE := $(ARCH)
  164. SRCARCH := $(ARCH)
  165. # Additional ARCH settings for x86
  166. ifeq ($(ARCH),i386)
  167. SRCARCH := x86
  168. endif
  169. ifeq ($(ARCH),x86_64)
  170. SRCARCH := x86
  171. endif
  172. # Additional ARCH settings for sparc
  173. ifeq ($(ARCH),sparc32)
  174. SRCARCH := sparc
  175. endif
  176. ifeq ($(ARCH),sparc64)
  177. SRCARCH := sparc
  178. endif
  179. # Additional ARCH settings for sh
  180. ifeq ($(ARCH),sh64)
  181. SRCARCH := sh
  182. endif
  183. # Where to locate arch specific headers
  184. hdr-arch := $(SRCARCH)
  185. ifeq ($(ARCH),m68knommu)
  186. hdr-arch := m68k
  187. endif
  188. KCONFIG_CONFIG ?= .config
  189. # SHELL used by kbuild
  190. CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
  191. else if [ -x /bin/bash ]; then echo /bin/bash; \
  192. else echo sh; fi ; fi)
  193. HOSTCC = gcc
  194. HOSTCXX = g++
  195. HOSTCFLAGS = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer
  196. HOSTCXXFLAGS = -O2
  197. # Decide whether to build built-in, modular, or both.
  198. # Normally, just do built-in.
  199. KBUILD_MODULES :=
  200. KBUILD_BUILTIN := 1
  201. # If we have only "make modules", don't compile built-in objects.
  202. # When we're building modules with modversions, we need to consider
  203. # the built-in objects during the descend as well, in order to
  204. # make sure the checksums are up to date before we record them.
  205. ifeq ($(MAKECMDGOALS),modules)
  206. KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
  207. endif
  208. # If we have "make <whatever> modules", compile modules
  209. # in addition to whatever we do anyway.
  210. # Just "make" or "make all" shall build modules as well
  211. ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
  212. KBUILD_MODULES := 1
  213. endif
  214. ifeq ($(MAKECMDGOALS),)
  215. KBUILD_MODULES := 1
  216. endif
  217. export KBUILD_MODULES KBUILD_BUILTIN
  218. export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
  219. # Beautify output
  220. # ---------------------------------------------------------------------------
  221. #
  222. # Normally, we echo the whole command before executing it. By making
  223. # that echo $($(quiet)$(cmd)), we now have the possibility to set
  224. # $(quiet) to choose other forms of output instead, e.g.
  225. #
  226. # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
  227. # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
  228. #
  229. # If $(quiet) is empty, the whole command will be printed.
  230. # If it is set to "quiet_", only the short version will be printed.
  231. # If it is set to "silent_", nothing will be printed at all, since
  232. # the variable $(silent_cmd_cc_o_c) doesn't exist.
  233. #
  234. # A simple variant is to prefix commands with $(Q) - that's useful
  235. # for commands that shall be hidden in non-verbose mode.
  236. #
  237. # $(Q)ln $@ :<
  238. #
  239. # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
  240. # If KBUILD_VERBOSE equals 1 then the above command is displayed.
  241. ifeq ($(KBUILD_VERBOSE),1)
  242. quiet =
  243. Q =
  244. else
  245. quiet=quiet_
  246. Q = @
  247. endif
  248. # If the user is running make -s (silent mode), suppress echoing of
  249. # commands
  250. ifneq ($(findstring s,$(MAKEFLAGS)),)
  251. quiet=silent_
  252. endif
  253. export quiet Q KBUILD_VERBOSE
  254. # Look for make include files relative to root of kernel src
  255. MAKEFLAGS += --include-dir=$(srctree)
  256. # We need some generic definitions (do not try to remake the file).
  257. $(srctree)/scripts/Kbuild.include: ;
  258. include $(srctree)/scripts/Kbuild.include
  259. # Make variables (CC, etc...)
  260. AS = $(CROSS_COMPILE)as
  261. LD = $(CROSS_COMPILE)ld
  262. CC = $(CROSS_COMPILE)gcc
  263. CPP = $(CC) -E
  264. AR = $(CROSS_COMPILE)ar
  265. NM = $(CROSS_COMPILE)nm
  266. STRIP = $(CROSS_COMPILE)strip
  267. OBJCOPY = $(CROSS_COMPILE)objcopy
  268. OBJDUMP = $(CROSS_COMPILE)objdump
  269. AWK = awk
  270. GENKSYMS = scripts/genksyms/genksyms
  271. INSTALLKERNEL := installkernel
  272. DEPMOD = /sbin/depmod
  273. KALLSYMS = scripts/kallsyms
  274. PERL = perl
  275. CHECK = sparse
  276. CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
  277. -Wbitwise -Wno-return-void $(CF)
  278. CFLAGS_MODULE =
  279. AFLAGS_MODULE =
  280. LDFLAGS_MODULE =
  281. CFLAGS_KERNEL =
  282. AFLAGS_KERNEL =
  283. CFLAGS_GCOV = -fprofile-arcs -ftest-coverage
  284. # Use LINUXINCLUDE when you must reference the include/ directory.
  285. # Needed to be compatible with the O= option
  286. LINUXINCLUDE := -I$(srctree)/arch/$(hdr-arch)/include -Iinclude \
  287. $(if $(KBUILD_SRC), -I$(srctree)/include) \
  288. -include include/generated/autoconf.h
  289. KBUILD_CPPFLAGS := -D__KERNEL__
  290. KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
  291. -fno-strict-aliasing -fno-common \
  292. -Werror-implicit-function-declaration \
  293. -Wno-format-security \
  294. -fno-delete-null-pointer-checks
  295. KBUILD_AFLAGS_KERNEL :=
  296. KBUILD_CFLAGS_KERNEL :=
  297. KBUILD_AFLAGS := -D__ASSEMBLY__
  298. KBUILD_AFLAGS_MODULE := -DMODULE
  299. KBUILD_CFLAGS_MODULE := -DMODULE
  300. KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
  301. # Read KERNELRELEASE from include/config/kernel.release (if it exists)
  302. KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
  303. KERNELVERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
  304. export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
  305. export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
  306. export CPP AR NM STRIP OBJCOPY OBJDUMP
  307. export MAKE AWK GENKSYMS INSTALLKERNEL PERL UTS_MACHINE
  308. export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
  309. export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
  310. export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV
  311. export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
  312. export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
  313. export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
  314. # When compiling out-of-tree modules, put MODVERDIR in the module
  315. # tree rather than in the kernel tree. The kernel tree might
  316. # even be read-only.
  317. export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
  318. # Files to ignore in find ... statements
  319. RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o -name CVS -o -name .pc -o -name .hg -o -name .git \) -prune -o
  320. export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn --exclude CVS --exclude .pc --exclude .hg --exclude .git
  321. # ===========================================================================
  322. # Rules shared between *config targets and build targets
  323. # Basic helpers built in scripts/
  324. PHONY += scripts_basic
  325. scripts_basic:
  326. $(Q)$(MAKE) $(build)=scripts/basic
  327. $(Q)rm -f .tmp_quiet_recordmcount
  328. # To avoid any implicit rule to kick in, define an empty command.
  329. scripts/basic/%: scripts_basic ;
  330. PHONY += outputmakefile
  331. # outputmakefile generates a Makefile in the output directory, if using a
  332. # separate output directory. This allows convenient use of make in the
  333. # output directory.
  334. outputmakefile:
  335. ifneq ($(KBUILD_SRC),)
  336. $(Q)ln -fsn $(srctree) source
  337. $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
  338. $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
  339. endif
  340. # To make sure we do not include .config for any of the *config targets
  341. # catch them early, and hand them over to scripts/kconfig/Makefile
  342. # It is allowed to specify more targets when calling make, including
  343. # mixing *config targets and build targets.
  344. # For example 'make oldconfig all'.
  345. # Detect when mixed targets is specified, and make a second invocation
  346. # of make so .config is not included in this case either (for *config).
  347. no-dot-config-targets := clean mrproper distclean \
  348. cscope gtags TAGS tags help %docs check% coccicheck \
  349. include/linux/version.h headers_% \
  350. kernelversion %src-pkg
  351. config-targets := 0
  352. mixed-targets := 0
  353. dot-config := 1
  354. ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
  355. ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
  356. dot-config := 0
  357. endif
  358. endif
  359. ifeq ($(KBUILD_EXTMOD),)
  360. ifneq ($(filter config %config,$(MAKECMDGOALS)),)
  361. config-targets := 1
  362. ifneq ($(filter-out config %config,$(MAKECMDGOALS)),)
  363. mixed-targets := 1
  364. endif
  365. endif
  366. endif
  367. ifeq ($(mixed-targets),1)
  368. # ===========================================================================
  369. # We're called with mixed targets (*config and build targets).
  370. # Handle them one by one.
  371. %:: FORCE
  372. $(Q)$(MAKE) -C $(srctree) KBUILD_SRC= $@
  373. else
  374. ifeq ($(config-targets),1)
  375. # ===========================================================================
  376. # *config targets only - make sure prerequisites are updated, and descend
  377. # in scripts/kconfig to make the *config target
  378. # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
  379. # KBUILD_DEFCONFIG may point out an alternative default configuration
  380. # used for 'make defconfig'
  381. include $(srctree)/arch/$(SRCARCH)/Makefile
  382. export KBUILD_DEFCONFIG KBUILD_KCONFIG
  383. config: scripts_basic outputmakefile FORCE
  384. $(Q)mkdir -p include/linux include/config
  385. $(Q)$(MAKE) $(build)=scripts/kconfig $@
  386. %config: scripts_basic outputmakefile FORCE
  387. $(Q)mkdir -p include/linux include/config
  388. $(Q)$(MAKE) $(build)=scripts/kconfig $@
  389. else
  390. # ===========================================================================
  391. # Build targets only - this includes vmlinux, arch specific targets, clean
  392. # targets and others. In general all targets except *config targets.
  393. ifeq ($(KBUILD_EXTMOD),)
  394. # Additional helpers built in scripts/
  395. # Carefully list dependencies so we do not try to build scripts twice
  396. # in parallel
  397. PHONY += scripts
  398. scripts: scripts_basic include/config/auto.conf include/config/tristate.conf
  399. $(Q)$(MAKE) $(build)=$(@)
  400. # Objects we will link into vmlinux / subdirs we need to visit
  401. init-y := init/
  402. drivers-y := drivers/ sound/ firmware/
  403. net-y := net/
  404. libs-y := lib/
  405. core-y := usr/
  406. endif # KBUILD_EXTMOD
  407. ifeq ($(dot-config),1)
  408. # Read in config
  409. -include include/config/auto.conf
  410. ifeq ($(KBUILD_EXTMOD),)
  411. # Read in dependencies to all Kconfig* files, make sure to run
  412. # oldconfig if changes are detected.
  413. -include include/config/auto.conf.cmd
  414. # To avoid any implicit rule to kick in, define an empty command
  415. $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
  416. # If .config is newer than include/config/auto.conf, someone tinkered
  417. # with it and forgot to run make oldconfig.
  418. # if auto.conf.cmd is missing then we are probably in a cleaned tree so
  419. # we execute the config step to be sure to catch updated Kconfig files
  420. include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
  421. $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
  422. else
  423. # external modules needs include/generated/autoconf.h and include/config/auto.conf
  424. # but do not care if they are up-to-date. Use auto.conf to trigger the test
  425. PHONY += include/config/auto.conf
  426. include/config/auto.conf:
  427. $(Q)test -e include/generated/autoconf.h -a -e $@ || ( \
  428. echo; \
  429. echo " ERROR: Kernel configuration is invalid."; \
  430. echo " include/generated/autoconf.h or $@ are missing.";\
  431. echo " Run 'make oldconfig && make prepare' on kernel src to fix it."; \
  432. echo; \
  433. /bin/false)
  434. endif # KBUILD_EXTMOD
  435. else
  436. # Dummy target needed, because used as prerequisite
  437. include/config/auto.conf: ;
  438. endif # $(dot-config)
  439. # The all: target is the default when no target is given on the
  440. # command line.
  441. # This allow a user to issue only 'make' to build a kernel including modules
  442. # Defaults to vmlinux, but the arch makefile usually adds further targets
  443. all: vmlinux
  444. ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
  445. KBUILD_CFLAGS += -Os
  446. else
  447. KBUILD_CFLAGS += -O2
  448. endif
  449. include $(srctree)/arch/$(SRCARCH)/Makefile
  450. ifneq ($(CONFIG_FRAME_WARN),0)
  451. KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
  452. endif
  453. # Force gcc to behave correct even for buggy distributions
  454. ifndef CONFIG_CC_STACKPROTECTOR
  455. KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector)
  456. endif
  457. ifdef CONFIG_FRAME_POINTER
  458. KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
  459. else
  460. # Some targets (ARM with Thumb2, for example), can't be built with frame
  461. # pointers. For those, we don't have FUNCTION_TRACER automatically
  462. # select FRAME_POINTER. However, FUNCTION_TRACER adds -pg, and this is
  463. # incompatible with -fomit-frame-pointer with current GCC, so we don't use
  464. # -fomit-frame-pointer with FUNCTION_TRACER.
  465. ifndef CONFIG_FUNCTION_TRACER
  466. KBUILD_CFLAGS += -fomit-frame-pointer
  467. endif
  468. endif
  469. ifdef CONFIG_DEBUG_INFO
  470. KBUILD_CFLAGS += -g
  471. KBUILD_AFLAGS += -gdwarf-2
  472. endif
  473. ifdef CONFIG_DEBUG_INFO_REDUCED
  474. KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly)
  475. endif
  476. ifdef CONFIG_FUNCTION_TRACER
  477. KBUILD_CFLAGS += -pg
  478. ifdef CONFIG_DYNAMIC_FTRACE
  479. ifdef CONFIG_HAVE_C_RECORDMCOUNT
  480. BUILD_C_RECORDMCOUNT := y
  481. export BUILD_C_RECORDMCOUNT
  482. endif
  483. endif
  484. endif
  485. # We trigger additional mismatches with less inlining
  486. ifdef CONFIG_DEBUG_SECTION_MISMATCH
  487. KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
  488. endif
  489. # arch Makefile may override CC so keep this after arch Makefile is included
  490. NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
  491. CHECKFLAGS += $(NOSTDINC_FLAGS)
  492. # warn about C99 declaration after statement
  493. KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
  494. # disable pointer signed / unsigned warnings in gcc 4.0
  495. KBUILD_CFLAGS += $(call cc-option,-Wno-pointer-sign,)
  496. # disable invalid "can't wrap" optimizations for signed / pointers
  497. KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
  498. # conserve stack if available
  499. KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
  500. # check for 'asm goto'
  501. ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y)
  502. KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
  503. endif
  504. # Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
  505. # But warn user when we do so
  506. warn-assign = \
  507. $(warning "WARNING: Appending $$K$(1) ($(K$(1))) from $(origin K$(1)) to kernel $$$(1)")
  508. ifneq ($(KCPPFLAGS),)
  509. $(call warn-assign,CPPFLAGS)
  510. KBUILD_CPPFLAGS += $(KCPPFLAGS)
  511. endif
  512. ifneq ($(KAFLAGS),)
  513. $(call warn-assign,AFLAGS)
  514. KBUILD_AFLAGS += $(KAFLAGS)
  515. endif
  516. ifneq ($(KCFLAGS),)
  517. $(call warn-assign,CFLAGS)
  518. KBUILD_CFLAGS += $(KCFLAGS)
  519. endif
  520. # Use --build-id when available.
  521. LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
  522. $(call cc-ldoption, -Wl$(comma)--build-id,))
  523. KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
  524. LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
  525. ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
  526. LDFLAGS_vmlinux += $(call ld-option, -X,)
  527. endif
  528. # Default kernel image to build when no specific target is given.
  529. # KBUILD_IMAGE may be overruled on the command line or
  530. # set in the environment
  531. # Also any assignments in arch/$(ARCH)/Makefile take precedence over
  532. # this default value
  533. export KBUILD_IMAGE ?= vmlinux
  534. #
  535. # INSTALL_PATH specifies where to place the updated kernel and system map
  536. # images. Default is /boot, but you can set it to other values
  537. export INSTALL_PATH ?= /boot
  538. #
  539. # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
  540. # relocations required by build roots. This is not defined in the
  541. # makefile but the argument can be passed to make if needed.
  542. #
  543. MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
  544. export MODLIB
  545. #
  546. # INSTALL_MOD_STRIP, if defined, will cause modules to be
  547. # stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
  548. # the default option --strip-debug will be used. Otherwise,
  549. # INSTALL_MOD_STRIP will used as the options to the strip command.
  550. ifdef INSTALL_MOD_STRIP
  551. ifeq ($(INSTALL_MOD_STRIP),1)
  552. mod_strip_cmd = $(STRIP) --strip-debug
  553. else
  554. mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
  555. endif # INSTALL_MOD_STRIP=1
  556. else
  557. mod_strip_cmd = true
  558. endif # INSTALL_MOD_STRIP
  559. export mod_strip_cmd
  560. ifeq ($(KBUILD_EXTMOD),)
  561. core-y += kernel/ mm/ fs/ ipc/ security/ crypto/ block/
  562. vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
  563. $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
  564. $(net-y) $(net-m) $(libs-y) $(libs-m)))
  565. vmlinux-alldirs := $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
  566. $(init-n) $(init-) \
  567. $(core-n) $(core-) $(drivers-n) $(drivers-) \
  568. $(net-n) $(net-) $(libs-n) $(libs-))))
  569. init-y := $(patsubst %/, %/built-in.o, $(init-y))
  570. core-y := $(patsubst %/, %/built-in.o, $(core-y))
  571. drivers-y := $(patsubst %/, %/built-in.o, $(drivers-y))
  572. net-y := $(patsubst %/, %/built-in.o, $(net-y))
  573. libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
  574. libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
  575. libs-y := $(libs-y1) $(libs-y2)
  576. # Build vmlinux
  577. # ---------------------------------------------------------------------------
  578. # vmlinux is built from the objects selected by $(vmlinux-init) and
  579. # $(vmlinux-main). Most are built-in.o files from top-level directories
  580. # in the kernel tree, others are specified in arch/$(ARCH)/Makefile.
  581. # Ordering when linking is important, and $(vmlinux-init) must be first.
  582. #
  583. # vmlinux
  584. # ^
  585. # |
  586. # +-< $(vmlinux-init)
  587. # | +--< init/version.o + more
  588. # |
  589. # +--< $(vmlinux-main)
  590. # | +--< driver/built-in.o mm/built-in.o + more
  591. # |
  592. # +-< kallsyms.o (see description in CONFIG_KALLSYMS section)
  593. #
  594. # vmlinux version (uname -v) cannot be updated during normal
  595. # descending-into-subdirs phase since we do not yet know if we need to
  596. # update vmlinux.
  597. # Therefore this step is delayed until just before final link of vmlinux -
  598. # except in the kallsyms case where it is done just before adding the
  599. # symbols to the kernel.
  600. #
  601. # System.map is generated to document addresses of all kernel symbols
  602. vmlinux-init := $(head-y) $(init-y)
  603. vmlinux-main := $(core-y) $(libs-y) $(drivers-y) $(net-y)
  604. vmlinux-all := $(vmlinux-init) $(vmlinux-main)
  605. vmlinux-lds := arch/$(SRCARCH)/kernel/vmlinux.lds
  606. export KBUILD_VMLINUX_OBJS := $(vmlinux-all)
  607. # Rule to link vmlinux - also used during CONFIG_KALLSYMS
  608. # May be overridden by arch/$(ARCH)/Makefile
  609. quiet_cmd_vmlinux__ ?= LD $@
  610. cmd_vmlinux__ ?= $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) -o $@ \
  611. -T $(vmlinux-lds) $(vmlinux-init) \
  612. --start-group $(vmlinux-main) --end-group \
  613. $(filter-out $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o FORCE ,$^)
  614. # Generate new vmlinux version
  615. quiet_cmd_vmlinux_version = GEN .version
  616. cmd_vmlinux_version = set -e; \
  617. if [ ! -r .version ]; then \
  618. rm -f .version; \
  619. echo 1 >.version; \
  620. else \
  621. mv .version .old_version; \
  622. expr 0$$(cat .old_version) + 1 >.version; \
  623. fi; \
  624. $(MAKE) $(build)=init
  625. # Generate System.map
  626. quiet_cmd_sysmap = SYSMAP
  627. cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap
  628. # Link of vmlinux
  629. # If CONFIG_KALLSYMS is set .version is already updated
  630. # Generate System.map and verify that the content is consistent
  631. # Use + in front of the vmlinux_version rule to silent warning with make -j2
  632. # First command is ':' to allow us to use + in front of the rule
  633. define rule_vmlinux__
  634. :
  635. $(if $(CONFIG_KALLSYMS),,+$(call cmd,vmlinux_version))
  636. $(call cmd,vmlinux__)
  637. $(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
  638. $(Q)$(if $($(quiet)cmd_sysmap), \
  639. echo ' $($(quiet)cmd_sysmap) System.map' &&) \
  640. $(cmd_sysmap) $@ System.map; \
  641. if [ $$? -ne 0 ]; then \
  642. rm -f $@; \
  643. /bin/false; \
  644. fi;
  645. $(verify_kallsyms)
  646. endef
  647. ifdef CONFIG_KALLSYMS
  648. # Generate section listing all symbols and add it into vmlinux $(kallsyms.o)
  649. # It's a three stage process:
  650. # o .tmp_vmlinux1 has all symbols and sections, but __kallsyms is
  651. # empty
  652. # Running kallsyms on that gives us .tmp_kallsyms1.o with
  653. # the right size - vmlinux version (uname -v) is updated during this step
  654. # o .tmp_vmlinux2 now has a __kallsyms section of the right size,
  655. # but due to the added section, some addresses have shifted.
  656. # From here, we generate a correct .tmp_kallsyms2.o
  657. # o The correct .tmp_kallsyms2.o is linked into the final vmlinux.
  658. # o Verify that the System.map from vmlinux matches the map from
  659. # .tmp_vmlinux2, just in case we did not generate kallsyms correctly.
  660. # o If CONFIG_KALLSYMS_EXTRA_PASS is set, do an extra pass using
  661. # .tmp_vmlinux3 and .tmp_kallsyms3.o. This is only meant as a
  662. # temporary bypass to allow the kernel to be built while the
  663. # maintainers work out what went wrong with kallsyms.
  664. ifdef CONFIG_KALLSYMS_EXTRA_PASS
  665. last_kallsyms := 3
  666. else
  667. last_kallsyms := 2
  668. endif
  669. kallsyms.o := .tmp_kallsyms$(last_kallsyms).o
  670. define verify_kallsyms
  671. $(Q)$(if $($(quiet)cmd_sysmap), \
  672. echo ' $($(quiet)cmd_sysmap) .tmp_System.map' &&) \
  673. $(cmd_sysmap) .tmp_vmlinux$(last_kallsyms) .tmp_System.map
  674. $(Q)cmp -s System.map .tmp_System.map || \
  675. (echo Inconsistent kallsyms data; \
  676. echo Try setting CONFIG_KALLSYMS_EXTRA_PASS; \
  677. rm .tmp_kallsyms* ; /bin/false )
  678. endef
  679. # Update vmlinux version before link
  680. # Use + in front of this rule to silent warning about make -j1
  681. # First command is ':' to allow us to use + in front of this rule
  682. cmd_ksym_ld = $(cmd_vmlinux__)
  683. define rule_ksym_ld
  684. :
  685. +$(call cmd,vmlinux_version)
  686. $(call cmd,vmlinux__)
  687. $(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
  688. endef
  689. # Generate .S file with all kernel symbols
  690. quiet_cmd_kallsyms = KSYM $@
  691. cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
  692. $(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
  693. .tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
  694. $(call if_changed_dep,as_o_S)
  695. .tmp_kallsyms%.S: .tmp_vmlinux% $(KALLSYMS)
  696. $(call cmd,kallsyms)
  697. # .tmp_vmlinux1 must be complete except kallsyms, so update vmlinux version
  698. .tmp_vmlinux1: $(vmlinux-lds) $(vmlinux-all) FORCE
  699. $(call if_changed_rule,ksym_ld)
  700. .tmp_vmlinux2: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms1.o FORCE
  701. $(call if_changed,vmlinux__)
  702. .tmp_vmlinux3: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms2.o FORCE
  703. $(call if_changed,vmlinux__)
  704. # Needs to visit scripts/ before $(KALLSYMS) can be used.
  705. $(KALLSYMS): scripts ;
  706. # Generate some data for debugging strange kallsyms problems
  707. debug_kallsyms: .tmp_map$(last_kallsyms)
  708. .tmp_map%: .tmp_vmlinux% FORCE
  709. ($(OBJDUMP) -h $< | $(AWK) '/^ +[0-9]/{print $$4 " 0 " $$2}'; $(NM) $<) | sort > $@
  710. .tmp_map3: .tmp_map2
  711. .tmp_map2: .tmp_map1
  712. endif # ifdef CONFIG_KALLSYMS
  713. # Do modpost on a prelinked vmlinux. The finally linked vmlinux has
  714. # relevant sections renamed as per the linker script.
  715. quiet_cmd_vmlinux-modpost = LD $@
  716. cmd_vmlinux-modpost = $(LD) $(LDFLAGS) -r -o $@ \
  717. $(vmlinux-init) --start-group $(vmlinux-main) --end-group \
  718. $(filter-out $(vmlinux-init) $(vmlinux-main) FORCE ,$^)
  719. define rule_vmlinux-modpost
  720. :
  721. +$(call cmd,vmlinux-modpost)
  722. $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost $@
  723. $(Q)echo 'cmd_$@ := $(cmd_vmlinux-modpost)' > $(dot-target).cmd
  724. endef
  725. # vmlinux image - including updated kernel symbols
  726. vmlinux: $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o $(kallsyms.o) FORCE
  727. ifdef CONFIG_HEADERS_CHECK
  728. $(Q)$(MAKE) -f $(srctree)/Makefile headers_check
  729. endif
  730. ifdef CONFIG_SAMPLES
  731. $(Q)$(MAKE) $(build)=samples
  732. endif
  733. ifdef CONFIG_BUILD_DOCSRC
  734. $(Q)$(MAKE) $(build)=Documentation
  735. endif
  736. $(call vmlinux-modpost)
  737. $(call if_changed_rule,vmlinux__)
  738. $(Q)rm -f .old_version
  739. # build vmlinux.o first to catch section mismatch errors early
  740. ifdef CONFIG_KALLSYMS
  741. .tmp_vmlinux1: vmlinux.o
  742. endif
  743. modpost-init := $(filter-out init/built-in.o, $(vmlinux-init))
  744. vmlinux.o: $(modpost-init) $(vmlinux-main) FORCE
  745. $(call if_changed_rule,vmlinux-modpost)
  746. # The actual objects are generated when descending,
  747. # make sure no implicit rule kicks in
  748. $(sort $(vmlinux-init) $(vmlinux-main)) $(vmlinux-lds): $(vmlinux-dirs) ;
  749. # Handle descending into subdirectories listed in $(vmlinux-dirs)
  750. # Preset locale variables to speed up the build process. Limit locale
  751. # tweaks to this spot to avoid wrong language settings when running
  752. # make menuconfig etc.
  753. # Error messages still appears in the original language
  754. PHONY += $(vmlinux-dirs)
  755. $(vmlinux-dirs): prepare scripts
  756. $(Q)$(MAKE) $(build)=$@
  757. # Store (new) KERNELRELASE string in include/config/kernel.release
  758. include/config/kernel.release: include/config/auto.conf FORCE
  759. $(Q)rm -f $@
  760. $(Q)echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))" > $@
  761. # Things we need to do before we recursively start building the kernel
  762. # or the modules are listed in "prepare".
  763. # A multi level approach is used. prepareN is processed before prepareN-1.
  764. # archprepare is used in arch Makefiles and when processed asm symlink,
  765. # version.h and scripts_basic is processed / created.
  766. # Listed in dependency order
  767. PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
  768. # prepare3 is used to check if we are building in a separate output directory,
  769. # and if so do:
  770. # 1) Check that make has not been executed in the kernel src $(srctree)
  771. prepare3: include/config/kernel.release
  772. ifneq ($(KBUILD_SRC),)
  773. @$(kecho) ' Using $(srctree) as source for kernel'
  774. $(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
  775. echo " $(srctree) is not clean, please run 'make mrproper'";\
  776. echo " in the '$(srctree)' directory.";\
  777. /bin/false; \
  778. fi;
  779. endif
  780. # prepare2 creates a makefile if using a separate output directory
  781. prepare2: prepare3 outputmakefile
  782. prepare1: prepare2 include/linux/version.h include/generated/utsrelease.h \
  783. include/config/auto.conf
  784. $(cmd_crmodverdir)
  785. archprepare: prepare1 scripts_basic
  786. prepare0: archprepare FORCE
  787. $(Q)$(MAKE) $(build)=.
  788. $(Q)$(MAKE) $(build)=. missing-syscalls
  789. # All the preparing..
  790. prepare: prepare0
  791. # Generate some files
  792. # ---------------------------------------------------------------------------
  793. # KERNELRELEASE can change from a few different places, meaning version.h
  794. # needs to be updated, so this check is forced on all builds
  795. uts_len := 64
  796. define filechk_utsrelease.h
  797. if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
  798. echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
  799. exit 1; \
  800. fi; \
  801. (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\";)
  802. endef
  803. define filechk_version.h
  804. (echo \#define LINUX_VERSION_CODE $(shell \
  805. expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
  806. echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))';)
  807. endef
  808. include/linux/version.h: $(srctree)/Makefile FORCE
  809. $(call filechk,version.h)
  810. include/generated/utsrelease.h: include/config/kernel.release FORCE
  811. $(call filechk,utsrelease.h)
  812. PHONY += headerdep
  813. headerdep:
  814. $(Q)find include/ -name '*.h' | xargs --max-args 1 scripts/headerdep.pl
  815. # ---------------------------------------------------------------------------
  816. PHONY += depend dep
  817. depend dep:
  818. @echo '*** Warning: make $@ is unnecessary now.'
  819. # ---------------------------------------------------------------------------
  820. # Firmware install
  821. INSTALL_FW_PATH=$(INSTALL_MOD_PATH)/lib/firmware
  822. export INSTALL_FW_PATH
  823. PHONY += firmware_install
  824. firmware_install: FORCE
  825. @mkdir -p $(objtree)/firmware
  826. $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_install
  827. # ---------------------------------------------------------------------------
  828. # Kernel headers
  829. #Default location for installed headers
  830. export INSTALL_HDR_PATH = $(objtree)/usr
  831. hdr-inst := -rR -f $(srctree)/scripts/Makefile.headersinst obj
  832. # If we do an all arch process set dst to asm-$(hdr-arch)
  833. hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
  834. PHONY += __headers
  835. __headers: include/linux/version.h scripts_basic FORCE
  836. $(Q)$(MAKE) $(build)=scripts scripts/unifdef
  837. PHONY += headers_install_all
  838. headers_install_all:
  839. $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh install
  840. PHONY += headers_install
  841. headers_install: __headers
  842. $(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/asm/Kbuild),, \
  843. $(error Headers not exportable for the $(SRCARCH) architecture))
  844. $(Q)$(MAKE) $(hdr-inst)=include
  845. $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/asm $(hdr-dst)
  846. PHONY += headers_check_all
  847. headers_check_all: headers_install_all
  848. $(Q)$(CONFIG_SHELL) $(srctree)/scripts/headers.sh check
  849. PHONY += headers_check
  850. headers_check: headers_install
  851. $(Q)$(MAKE) $(hdr-inst)=include HDRCHECK=1
  852. $(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/asm $(hdr-dst) HDRCHECK=1
  853. # ---------------------------------------------------------------------------
  854. # Modules
  855. ifdef CONFIG_MODULES
  856. # By default, build modules as well
  857. all: modules
  858. # Build modules
  859. #
  860. # A module can be listed more than once in obj-m resulting in
  861. # duplicate lines in modules.order files. Those are removed
  862. # using awk while concatenating to the final file.
  863. PHONY += modules
  864. modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin
  865. $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order
  866. @$(kecho) ' Building modules, stage 2.';
  867. $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
  868. $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modbuild
  869. modules.builtin: $(vmlinux-dirs:%=%/modules.builtin)
  870. $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin
  871. %/modules.builtin: include/config/auto.conf
  872. $(Q)$(MAKE) $(modbuiltin)=$*
  873. # Target to prepare building external modules
  874. PHONY += modules_prepare
  875. modules_prepare: prepare scripts
  876. # Target to install modules
  877. PHONY += modules_install
  878. modules_install: _modinst_ _modinst_post
  879. PHONY += _modinst_
  880. _modinst_:
  881. @if [ -z "`$(DEPMOD) -V 2>/dev/null | grep module-init-tools`" ]; then \
  882. echo "Warning: you may need to install module-init-tools"; \
  883. echo "See http://www.codemonkey.org.uk/docs/post-halloween-2.6.txt";\
  884. sleep 1; \
  885. fi
  886. @rm -rf $(MODLIB)/kernel
  887. @rm -f $(MODLIB)/source
  888. @mkdir -p $(MODLIB)/kernel
  889. @ln -s $(srctree) $(MODLIB)/source
  890. @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
  891. rm -f $(MODLIB)/build ; \
  892. ln -s $(objtree) $(MODLIB)/build ; \
  893. fi
  894. @cp -f $(objtree)/modules.order $(MODLIB)/
  895. @cp -f $(objtree)/modules.builtin $(MODLIB)/
  896. $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
  897. # This depmod is only for convenience to give the initial
  898. # boot a modules.dep even before / is mounted read-write. However the
  899. # boot script depmod is the master version.
  900. PHONY += _modinst_post
  901. _modinst_post: _modinst_
  902. $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst
  903. $(call cmd,depmod)
  904. else # CONFIG_MODULES
  905. # Modules not configured
  906. # ---------------------------------------------------------------------------
  907. modules modules_install: FORCE
  908. @echo
  909. @echo "The present kernel configuration has modules disabled."
  910. @echo "Type 'make config' and enable loadable module support."
  911. @echo "Then build a kernel with module support enabled."
  912. @echo
  913. @exit 1
  914. endif # CONFIG_MODULES
  915. ###
  916. # Cleaning is done on three levels.
  917. # make clean Delete most generated files
  918. # Leave enough to build external modules
  919. # make mrproper Delete the current configuration, and all generated files
  920. # make distclean Remove editor backup files, patch leftover files and the like
  921. # Directories & files removed with 'make clean'
  922. CLEAN_DIRS += $(MODVERDIR)
  923. CLEAN_FILES += vmlinux System.map \
  924. .tmp_kallsyms* .tmp_version .tmp_vmlinux* .tmp_System.map
  925. # Directories & files removed with 'make mrproper'
  926. MRPROPER_DIRS += include/config usr/include include/generated
  927. MRPROPER_FILES += .config .config.old .version .old_version \
  928. include/linux/version.h \
  929. Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
  930. # clean - Delete most, but leave enough to build external modules
  931. #
  932. clean: rm-dirs := $(CLEAN_DIRS)
  933. clean: rm-files := $(CLEAN_FILES)
  934. clean-dirs := $(addprefix _clean_, . $(vmlinux-alldirs) Documentation)
  935. PHONY += $(clean-dirs) clean archclean
  936. $(clean-dirs):
  937. $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
  938. clean: archclean
  939. # mrproper - Delete all generated files, including .config
  940. #
  941. mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
  942. mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
  943. mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
  944. PHONY += $(mrproper-dirs) mrproper archmrproper
  945. $(mrproper-dirs):
  946. $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
  947. mrproper: clean archmrproper $(mrproper-dirs)
  948. $(call cmd,rmdirs)
  949. $(call cmd,rmfiles)
  950. # distclean
  951. #
  952. PHONY += distclean
  953. distclean: mrproper
  954. @find $(srctree) $(RCS_FIND_IGNORE) \
  955. \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
  956. -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
  957. -o -name '.*.rej' -o -size 0 \
  958. -o -name '*%' -o -name '.*.cmd' -o -name 'core' \) \
  959. -type f -print | xargs rm -f
  960. # Packaging of the kernel to various formats
  961. # ---------------------------------------------------------------------------
  962. # rpm target kept for backward compatibility
  963. package-dir := $(srctree)/scripts/package
  964. %src-pkg: FORCE
  965. $(Q)$(MAKE) $(build)=$(package-dir) $@
  966. %pkg: include/config/kernel.release FORCE
  967. $(Q)$(MAKE) $(build)=$(package-dir) $@
  968. rpm: include/config/kernel.release FORCE
  969. $(Q)$(MAKE) $(build)=$(package-dir) $@
  970. # Brief documentation of the typical targets used
  971. # ---------------------------------------------------------------------------
  972. boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
  973. boards := $(notdir $(boards))
  974. board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
  975. board-dirs := $(sort $(notdir $(board-dirs:/=)))
  976. help:
  977. @echo 'Cleaning targets:'
  978. @echo ' clean - Remove most generated files but keep the config and'
  979. @echo ' enough build support to build external modules'
  980. @echo ' mrproper - Remove all generated files + config + various backup files'
  981. @echo ' distclean - mrproper + remove editor backup and patch files'
  982. @echo ''
  983. @echo 'Configuration targets:'
  984. @$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
  985. @echo ''
  986. @echo 'Other generic targets:'
  987. @echo ' all - Build all targets marked with [*]'
  988. @echo '* vmlinux - Build the bare kernel'
  989. @echo '* modules - Build all modules'
  990. @echo ' modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
  991. @echo ' firmware_install- Install all firmware to INSTALL_FW_PATH'
  992. @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)'
  993. @echo ' dir/ - Build all files in dir and below'
  994. @echo ' dir/file.[oisS] - Build specified target only'
  995. @echo ' dir/file.lst - Build specified mixed source/assembly target only'
  996. @echo ' (requires a recent binutils and recent build (System.map))'
  997. @echo ' dir/file.ko - Build module including final link'
  998. @echo ' modules_prepare - Set up for building external modules'
  999. @echo ' tags/TAGS - Generate tags file for editors'
  1000. @echo ' cscope - Generate cscope index'
  1001. @echo ' gtags - Generate GNU GLOBAL index'
  1002. @echo ' kernelrelease - Output the release version string'
  1003. @echo ' kernelversion - Output the version stored in Makefile'
  1004. @echo ' headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
  1005. echo ' (default: $(INSTALL_HDR_PATH))'; \
  1006. echo ''
  1007. @echo 'Static analysers'
  1008. @echo ' checkstack - Generate a list of stack hogs'
  1009. @echo ' namespacecheck - Name space analysis on compiled kernel'
  1010. @echo ' versioncheck - Sanity check on version.h usage'
  1011. @echo ' includecheck - Check for duplicate included header files'
  1012. @echo ' export_report - List the usages of all exported symbols'
  1013. @echo ' headers_check - Sanity check on exported headers'
  1014. @echo ' headerdep - Detect inclusion cycles in headers'
  1015. @$(MAKE) -f $(srctree)/scripts/Makefile.help checker-help
  1016. @echo ''
  1017. @echo 'Kernel packaging:'
  1018. @$(MAKE) $(build)=$(package-dir) help
  1019. @echo ''
  1020. @echo 'Documentation targets:'
  1021. @$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
  1022. @echo ''
  1023. @echo 'Architecture specific targets ($(SRCARCH)):'
  1024. @$(if $(archhelp),$(archhelp),\
  1025. echo ' No architecture specific help defined for $(SRCARCH)')
  1026. @echo ''
  1027. @$(if $(boards), \
  1028. $(foreach b, $(boards), \
  1029. printf " %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
  1030. echo '')
  1031. @$(if $(board-dirs), \
  1032. $(foreach b, $(board-dirs), \
  1033. printf " %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
  1034. printf " %-16s - Show all of the above\\n" help-boards; \
  1035. echo '')
  1036. @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
  1037. @echo ' make V=2 [targets] 2 => give reason for rebuild of target'
  1038. @echo ' make O=dir [targets] Locate all output files in "dir", including .config'
  1039. @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)'
  1040. @echo ' make C=2 [targets] Force check of all c source with $$CHECK'
  1041. @echo ''
  1042. @echo 'Execute "make" or "make all" to build all targets marked with [*] '
  1043. @echo 'For further info see the ./README file'
  1044. help-board-dirs := $(addprefix help-,$(board-dirs))
  1045. help-boards: $(help-board-dirs)
  1046. boards-per-dir = $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig))
  1047. $(help-board-dirs): help-%:
  1048. @echo 'Architecture specific targets ($(SRCARCH) $*):'
  1049. @$(if $(boards-per-dir), \
  1050. $(foreach b, $(boards-per-dir), \
  1051. printf " %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
  1052. echo '')
  1053. # Documentation targets
  1054. # ---------------------------------------------------------------------------
  1055. %docs: scripts_basic FORCE
  1056. $(Q)$(MAKE) $(build)=Documentation/DocBook $@
  1057. else # KBUILD_EXTMOD
  1058. ###
  1059. # External module support.
  1060. # When building external modules the kernel used as basis is considered
  1061. # read-only, and no consistency checks are made and the make
  1062. # system is not used on the basis kernel. If updates are required
  1063. # in the basis kernel ordinary make commands (without M=...) must
  1064. # be used.
  1065. #
  1066. # The following are the only valid targets when building external
  1067. # modules.
  1068. # make M=dir clean Delete all automatically generated files
  1069. # make M=dir modules Make all modules in specified dir
  1070. # make M=dir Same as 'make M=dir modules'
  1071. # make M=dir modules_install
  1072. # Install the modules built in the module directory
  1073. # Assumes install directory is already created
  1074. # We are always building modules
  1075. KBUILD_MODULES := 1
  1076. PHONY += crmodverdir
  1077. crmodverdir:
  1078. $(cmd_crmodverdir)
  1079. PHONY += $(objtree)/Module.symvers
  1080. $(objtree)/Module.symvers:
  1081. @test -e $(objtree)/Module.symvers || ( \
  1082. echo; \
  1083. echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
  1084. echo " is missing; modules will have no dependencies and modversions."; \
  1085. echo )
  1086. module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
  1087. PHONY += $(module-dirs) modules
  1088. $(module-dirs): crmodverdir $(objtree)/Module.symvers
  1089. $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
  1090. modules: $(module-dirs)
  1091. @$(kecho) ' Building modules, stage 2.';
  1092. $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
  1093. PHONY += modules_install
  1094. modules_install: _emodinst_ _emodinst_post
  1095. install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
  1096. PHONY += _emodinst_
  1097. _emodinst_:
  1098. $(Q)mkdir -p $(MODLIB)/$(install-dir)
  1099. $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
  1100. PHONY += _emodinst_post
  1101. _emodinst_post: _emodinst_
  1102. $(call cmd,depmod)
  1103. clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
  1104. PHONY += $(clean-dirs) clean
  1105. $(clean-dirs):
  1106. $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
  1107. clean: rm-dirs := $(MODVERDIR)
  1108. clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
  1109. help:
  1110. @echo ' Building external modules.'
  1111. @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
  1112. @echo ''
  1113. @echo ' modules - default target, build the module(s)'
  1114. @echo ' modules_install - install the module'
  1115. @echo ' clean - remove generated files in module directory only'
  1116. @echo ''
  1117. # Dummies...
  1118. PHONY += prepare scripts
  1119. prepare: ;
  1120. scripts: ;
  1121. endif # KBUILD_EXTMOD
  1122. clean: $(clean-dirs)
  1123. $(call cmd,rmdirs)
  1124. $(call cmd,rmfiles)
  1125. @find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
  1126. \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
  1127. -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
  1128. -o -name '*.symtypes' -o -name 'modules.order' \
  1129. -o -name modules.builtin -o -name '.tmp_*.o.*' \
  1130. -o -name '*.gcno' \) -type f -print | xargs rm -f
  1131. # Generate tags for editors
  1132. # ---------------------------------------------------------------------------
  1133. quiet_cmd_tags = GEN $@
  1134. cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
  1135. tags TAGS cscope gtags: FORCE
  1136. $(call cmd,tags)
  1137. # Scripts to check various things for consistency
  1138. # ---------------------------------------------------------------------------
  1139. includecheck:
  1140. find * $(RCS_FIND_IGNORE) \
  1141. -name '*.[hcS]' -type f -print | sort \
  1142. | xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
  1143. versioncheck:
  1144. find * $(RCS_FIND_IGNORE) \
  1145. -name '*.[hcS]' -type f -print | sort \
  1146. | xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
  1147. coccicheck:
  1148. $(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
  1149. namespacecheck:
  1150. $(PERL) $(srctree)/scripts/namespace.pl
  1151. export_report:
  1152. $(PERL) $(srctree)/scripts/export_report.pl
  1153. endif #ifeq ($(config-targets),1)
  1154. endif #ifeq ($(mixed-targets),1)
  1155. PHONY += checkstack kernelrelease kernelversion
  1156. # UML needs a little special treatment here. It wants to use the host
  1157. # toolchain, so needs $(SUBARCH) passed to checkstack.pl. Everyone
  1158. # else wants $(ARCH), including people doing cross-builds, which means
  1159. # that $(SUBARCH) doesn't work here.
  1160. ifeq ($(ARCH), um)
  1161. CHECKSTACK_ARCH := $(SUBARCH)
  1162. else
  1163. CHECKSTACK_ARCH := $(ARCH)
  1164. endif
  1165. checkstack:
  1166. $(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
  1167. $(PERL) $(src)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
  1168. kernelrelease:
  1169. @echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
  1170. kernelversion:
  1171. @echo $(KERNELVERSION)
  1172. # Single targets
  1173. # ---------------------------------------------------------------------------
  1174. # Single targets are compatible with:
  1175. # - build with mixed source and output
  1176. # - build with separate output dir 'make O=...'
  1177. # - external modules
  1178. #
  1179. # target-dir => where to store outputfile
  1180. # build-dir => directory in kernel source tree to use
  1181. ifeq ($(KBUILD_EXTMOD),)
  1182. build-dir = $(patsubst %/,%,$(dir $@))
  1183. target-dir = $(dir $@)
  1184. else
  1185. zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
  1186. build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
  1187. target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
  1188. endif
  1189. %.s: %.c prepare scripts FORCE
  1190. $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
  1191. %.i: %.c prepare scripts FORCE
  1192. $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
  1193. %.o: %.c prepare scripts FORCE
  1194. $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
  1195. %.lst: %.c prepare scripts FORCE
  1196. $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
  1197. %.s: %.S prepare scripts FORCE
  1198. $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
  1199. %.o: %.S prepare scripts FORCE
  1200. $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
  1201. %.symtypes: %.c prepare scripts FORCE
  1202. $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
  1203. # Modules
  1204. /: prepare scripts FORCE
  1205. $(cmd_crmodverdir)
  1206. $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
  1207. $(build)=$(build-dir)
  1208. %/: prepare scripts FORCE
  1209. $(cmd_crmodverdir)
  1210. $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
  1211. $(build)=$(build-dir)
  1212. %.ko: prepare scripts FORCE
  1213. $(cmd_crmodverdir)
  1214. $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
  1215. $(build)=$(build-dir) $(@:.ko=.o)
  1216. $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
  1217. # FIXME Should go into a make.lib or something
  1218. # ===========================================================================
  1219. quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
  1220. cmd_rmdirs = rm -rf $(rm-dirs)
  1221. quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
  1222. cmd_rmfiles = rm -f $(rm-files)
  1223. # Run depmod only if we have System.map and depmod is executable
  1224. quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
  1225. cmd_depmod = \
  1226. if [ -r System.map -a -x $(DEPMOD) ]; then \
  1227. $(DEPMOD) -ae -F System.map \
  1228. $(if $(strip $(INSTALL_MOD_PATH)), -b $(INSTALL_MOD_PATH) ) \
  1229. $(KERNELRELEASE); \
  1230. fi
  1231. # Create temporary dir for module support files
  1232. # clean it up only when building all modules
  1233. cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
  1234. $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)
  1235. a_flags = -Wp,-MD,$(depfile) $(KBUILD_AFLAGS) $(AFLAGS_KERNEL) \
  1236. $(KBUILD_AFLAGS_KERNEL) \
  1237. $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(KBUILD_CPPFLAGS) \
  1238. $(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(basetarget).o)
  1239. quiet_cmd_as_o_S = AS $@
  1240. cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
  1241. # read all saved command lines
  1242. targets := $(wildcard $(sort $(targets)))
  1243. cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
  1244. ifneq ($(cmd_files),)
  1245. $(cmd_files): ; # Do not try to update included dependency files
  1246. include $(cmd_files)
  1247. endif
  1248. # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=dir
  1249. # Usage:
  1250. # $(Q)$(MAKE) $(clean)=dir
  1251. clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj
  1252. endif # skip-makefile
  1253. PHONY += FORCE
  1254. FORCE:
  1255. # Declare the contents of the .PHONY variable as phony. We keep that
  1256. # information in a variable so we can use it in if_changed and friends.
  1257. .PHONY: $(PHONY)