Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/gi…

…t/mmarek/kbuild-2.6

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  kbuild: make KBUILD_NOCMDDEP=1 handle empty built-in.o
  scripts/kallsyms.c: fix potential segfault
  scripts/gen_initramfs_list.sh: Convert to a /bin/sh script
  kbuild: Fix GNU make v3.80 compatibility
  kbuild: Fix passing -Wno-* options to gcc 4.4+
  kbuild: move scripts/basic/docproc.c to scripts/docproc.c
  kbuild: Fix Makefile.asm-generic for um
  kbuild: Allow to combine multiple W= levels
  kbuild: Disable -Wunused-but-set-variable for gcc 4.6.0
  Fix handling of backlash character in LINUX_COMPILE_BY name
  kbuild: asm-generic support
  kbuild: implement several W= levels
  kbuild: Fix build with binutils <= 2.19
  initramfs: Use KBUILD_BUILD_TIMESTAMP for generated entries
  kbuild: Allow to override LINUX_COMPILE_BY and LINUX_COMPILE_HOST macros
  kbuild: Drop unused LINUX_COMPILE_TIME and LINUX_COMPILE_DOMAIN macros
  kbuild: Use the deterministic mode of ar
  kbuild: Call gzip with -n
  kbuild: move KALLSYMS_EXTRA_PASS from Kconfig to Makefile
  Kconfig: improve KALLSYMS_ALL documentation

Fix up trivial conflict in Makefile

.gitignore

@@ -57,6 +57,7 @@ modules.builtin
 include/config
 include/linux/version.h
 include/generated
+arch/*/include/generated
 
 # stgit generated dirs
 patches-*

Documentation/DocBook/Makefile

@@ -73,7 +73,7 @@ installmandocs: mandocs
 ###
 #External programs used
 KERNELDOC = $(srctree)/scripts/kernel-doc
-DOCPROC   = $(objtree)/scripts/basic/docproc
+DOCPROC   = $(objtree)/scripts/docproc
 
 XMLTOFLAGS = -m $(srctree)/Documentation/DocBook/stylesheet.xsl
 XMLTOFLAGS += --skip-validation

Documentation/kbuild/kbuild.txt

@@ -201,3 +201,16 @@ KBUILD_ENABLE_EXTRA_GCC_CHECKS
 --------------------------------------------------
 If enabled over the make command line with "W=1", it turns on additional
 gcc -W... options for more extensive build-time checking.
+
+KBUILD_BUILD_TIMESTAMP
+--------------------------------------------------
+Setting this to a date string overrides the timestamp used in the
+UTS_VERSION definition (uname -v in the running kernel). The value has to
+be a string that can be passed to date -d. The default value
+is the output of the date command at one point during build.
+
+KBUILD_BUILD_USER, KBUILD_BUILD_HOST
+--------------------------------------------------
+These two variables allow to override the user@host string displayed during
+boot and in /proc/version. The default value is the output of the commands
+whoami and host, respectively.

Documentation/kbuild/makefiles.txt

@@ -40,11 +40,13 @@ This document describes the Linux kernel Makefiles.
 	   --- 6.6 Commands useful for building a boot image
 	   --- 6.7 Custom kbuild commands
 	   --- 6.8 Preprocessing linker scripts
+	   --- 6.9 Generic header files
 
 	=== 7 Kbuild syntax for exported headers
 		--- 7.1 header-y
 		--- 7.2 objhdr-y
 		--- 7.3 destination-y
+		--- 7.4 generic-y
 
 	=== 8 Kbuild Variables
 	=== 9 Makefile language
@@ -499,6 +501,18 @@ more details, with real examples.
 	gcc >= 3.00. For gcc < 3.00, -malign-functions=4 is used.
 	Note: cc-option-align uses KBUILD_CFLAGS for $(CC) options
 
+    cc-disable-warning
+	cc-disable-warning checks if gcc supports a given warning and returns
+	the commandline switch to disable it. This special function is needed,
+	because gcc 4.4 and later accept any unknown -Wno-* option and only
+	warn about it if there is another warning in the source file.
+
+	Example:
+		KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
+
+	In the above example, -Wno-unused-but-set-variable will be added to
+	KBUILD_CFLAGS only if gcc really accepts it.
+
     cc-version
 	cc-version returns a numerical version of the $(CC) compiler version.
 	The format is <major><minor> where both are two digits. So for example
@@ -955,6 +969,11 @@ When kbuild executes, the following steps are followed (roughly):
 	used when linking modules. This is often a linker script.
 	From commandline LDFLAGS_MODULE shall be used (see kbuild.txt).
 
+    KBUILD_ARFLAGS   Options for $(AR) when creating archives
+
+	$(KBUILD_ARFLAGS) set by the top level Makefile to "D" (deterministic
+	mode) if this option is supported by $(AR).
+
 --- 6.2 Add prerequisites to archprepare:
 
 	The archprepare: rule is used to list prerequisites that need to be
@@ -1209,6 +1228,14 @@ When kbuild executes, the following steps are followed (roughly):
 	The kbuild infrastructure for *lds file are used in several
 	architecture-specific files.
 
+--- 6.9 Generic header files
+
+	The directory include/asm-generic contains the header files
+	that may be shared between individual architectures.
+	The recommended approach how to use a generic header file is
+	to list the file in the Kbuild file.
+	See "7.4 generic-y" for further info on syntax etc.
+
 === 7 Kbuild syntax for exported headers
 
 The kernel include a set of headers that is exported to userspace.
@@ -1265,6 +1292,32 @@ See subsequent chapter for the syntax of the Kbuild file.
 	In the example above all exported headers in the Kbuild file
 	will be located in the directory "include/linux" when exported.
 
+	--- 7.4 generic-y
+
+	If an architecture uses a verbatim copy of a header from
+	include/asm-generic then this is listed in the file
+	arch/$(ARCH)/include/asm/Kbuild like this:
+
+		Example:
+			#arch/x86/include/asm/Kbuild
+			generic-y += termios.h
+			generic-y += rtc.h
+
+	During the prepare phase of the build a wrapper include
+	file is generated in the directory:
+
+		arch/$(ARCH)/include/generated/asm
+
+	When a header is exported where the architecture uses
+	the generic header a similar wrapper is generated as part
+	of the set of exported headers in the directory:
+
+		usr/include/asm
+
+	The generated wrapper will in both cases look like the following:
+
+		Example: termios.h
+			#include <asm-generic/termios.h>
 
 === 8 Kbuild Variables
 

Makefile

@@ -103,7 +103,7 @@ ifeq ("$(origin O)", "command line")
 endif
 
 ifeq ("$(origin W)", "command line")
-  export KBUILD_ENABLE_EXTRA_GCC_CHECKS := 1
+  export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
 endif
 
 # That's our default target when none is given on the command line
@@ -349,7 +349,8 @@ CFLAGS_GCOV	= -fprofile-arcs -ftest-coverage
 
 # Use LINUXINCLUDE when you must reference the include/ directory.
 # Needed to be compatible with the O= option
-LINUXINCLUDE    := -I$(srctree)/arch/$(hdr-arch)/include -Iinclude \
+LINUXINCLUDE    := -I$(srctree)/arch/$(hdr-arch)/include \
+                   -Iarch/$(hdr-arch)/include/generated -Iinclude \
                    $(if $(KBUILD_SRC), -I$(srctree)/include) \
                    -include include/generated/autoconf.h
 
@@ -382,6 +383,7 @@ export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV
 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
+export KBUILD_ARFLAGS
 
 # When compiling out-of-tree modules, put MODVERDIR in the module
 # tree rather than in the kernel tree. The kernel tree might
@@ -416,6 +418,12 @@ ifneq ($(KBUILD_SRC),)
 	    $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
 endif
 
+# Support for using generic headers in asm-generic
+PHONY += asm-generic
+asm-generic:
+	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
+	            obj=arch/$(SRCARCH)/include/generated/asm
+
 # To make sure we do not include .config for any of the *config targets
 # catch them early, and hand them over to scripts/kconfig/Makefile
 # It is allowed to specify more targets when calling make, including
@@ -559,6 +567,10 @@ ifndef CONFIG_CC_STACKPROTECTOR
 KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector)
 endif
 
+# This warning generated too much noise in a regular build.
+# Use make W=1 to enable this warning (see scripts/Makefile.build)
+KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
+
 ifdef CONFIG_FRAME_POINTER
 KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
 else
@@ -604,14 +616,17 @@ CHECKFLAGS     += $(NOSTDINC_FLAGS)
 KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
 
 # disable pointer signed / unsigned warnings in gcc 4.0
-KBUILD_CFLAGS += $(call cc-option,-Wno-pointer-sign,)
+KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign)
 
 # disable invalid "can't wrap" optimizations for signed / pointers
 KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
 
 # conserve stack if available
 KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
 
+# use the deterministic mode of AR if available
+KBUILD_ARFLAGS := $(call ar-option,D)
+
 # check for 'asm goto'
 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y)
 	KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
@@ -797,15 +812,17 @@ ifdef CONFIG_KALLSYMS
 # o The correct .tmp_kallsyms2.o is linked into the final vmlinux.
 # o Verify that the System.map from vmlinux matches the map from
 #   .tmp_vmlinux2, just in case we did not generate kallsyms correctly.
-# o If CONFIG_KALLSYMS_EXTRA_PASS is set, do an extra pass using
+# o If 'make KALLSYMS_EXTRA_PASS=1" was used, do an extra pass using
 #   .tmp_vmlinux3 and .tmp_kallsyms3.o.  This is only meant as a
 #   temporary bypass to allow the kernel to be built while the
 #   maintainers work out what went wrong with kallsyms.
 
-ifdef CONFIG_KALLSYMS_EXTRA_PASS
-last_kallsyms := 3
-else
 last_kallsyms := 2
+
+ifdef KALLSYMS_EXTRA_PASS
+ifneq ($(KALLSYMS_EXTRA_PASS),0)
+last_kallsyms := 3
+endif
 endif
 
 kallsyms.o := .tmp_kallsyms$(last_kallsyms).o
@@ -816,7 +833,8 @@ define verify_kallsyms
 	  $(cmd_sysmap) .tmp_vmlinux$(last_kallsyms) .tmp_System.map
 	$(Q)cmp -s System.map .tmp_System.map ||                             \
 		(echo Inconsistent kallsyms data;                            \
-		 echo Try setting CONFIG_KALLSYMS_EXTRA_PASS;                \
+		 echo This is a bug - please report about it;                \
+		 echo Try "make KALLSYMS_EXTRA_PASS=1" as a workaround;      \
 		 rm .tmp_kallsyms* ; /bin/false )
 endef
 
@@ -947,7 +965,7 @@ ifneq ($(KBUILD_SRC),)
 endif
 
 # prepare2 creates a makefile if using a separate output directory
-prepare2: prepare3 outputmakefile
+prepare2: prepare3 outputmakefile asm-generic
 
 prepare1: prepare2 include/linux/version.h include/generated/utsrelease.h \
                    include/config/auto.conf
@@ -1021,7 +1039,7 @@ hdr-inst := -rR -f $(srctree)/scripts/Makefile.headersinst obj
 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
 
 PHONY += __headers
-__headers: include/linux/version.h scripts_basic FORCE
+__headers: include/linux/version.h scripts_basic asm-generic FORCE
 	$(Q)$(MAKE) $(build)=scripts build_unifdef
 
 PHONY += headers_install_all
@@ -1136,7 +1154,8 @@ CLEAN_FILES +=	vmlinux System.map \
                 .tmp_kallsyms* .tmp_version .tmp_vmlinux* .tmp_System.map
 
 # Directories & files removed with 'make mrproper'
-MRPROPER_DIRS  += include/config usr/include include/generated
+MRPROPER_DIRS  += include/config usr/include include/generated          \
+                  arch/*/include/generated
 MRPROPER_FILES += .config .config.old .version .old_version             \
                   include/linux/version.h                               \
 		  Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
@@ -1267,7 +1286,11 @@ help:
 	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
 	@echo  '  make C=1   [targets] Check all c source with $$CHECK (sparse by default)'
 	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
-	@echo  '  make W=1   [targets] Enable extra gcc checks'
+	@echo  '  make W=n   [targets] Enable extra gcc checks, n=1,2,3 where'
+	@echo  '		1: warnings which may be relevant and do not occur too often'
+	@echo  '		2: warnings which occur quite often but may still be relevant'
+	@echo  '		3: more obscure warnings, can most likely be ignored'
+	@echo  '		Multiple levels can be combined with W=12 or W=123'
 	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
 	@echo  ''
 	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
@@ -1291,6 +1314,7 @@ $(help-board-dirs): help-%:
 # Documentation targets
 # ---------------------------------------------------------------------------
 %docs: scripts_basic FORCE
+	$(Q)$(MAKE) $(build)=scripts build_docproc
 	$(Q)$(MAKE) $(build)=Documentation/DocBook $@
 
 else # KBUILD_EXTMOD
@@ -1375,7 +1399,7 @@ endif # KBUILD_EXTMOD
 clean: $(clean-dirs)
 	$(call cmd,rmdirs)
 	$(call cmd,rmfiles)
-	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
+	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
 		\( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
 		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
 		-o -name '*.symtypes' -o -name 'modules.order' \

init/Kconfig

@@ -959,24 +959,18 @@ config KALLSYMS_ALL
 	bool "Include all symbols in kallsyms"
 	depends on DEBUG_KERNEL && KALLSYMS
 	help
-	   Normally kallsyms only contains the symbols of functions, for nicer
-	   OOPS messages.  Some debuggers can use kallsyms for other
-	   symbols too: say Y here to include all symbols, if you need them 
-	   and you don't care about adding 300k to the size of your kernel.
-
-	   Say N.
-
-config KALLSYMS_EXTRA_PASS
-	bool "Do an extra kallsyms pass"
-	depends on KALLSYMS
-	help
-	   If kallsyms is not working correctly, the build will fail with
-	   inconsistent kallsyms data.  If that occurs, log a bug report and
-	   turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
-	   Always say N here unless you find a bug in kallsyms, which must be
-	   reported.  KALLSYMS_EXTRA_PASS is only a temporary workaround while
-	   you wait for kallsyms to be fixed.
-
+	   Normally kallsyms only contains the symbols of functions for nicer
+	   OOPS messages and backtraces (i.e., symbols from the text and inittext
+	   sections). This is sufficient for most cases. And only in very rare
+	   cases (e.g., when a debugger is used) all symbols are required (e.g.,
+	   names of variables from the data sections, etc).
+
+	   This option makes sure that all symbols are loaded into the kernel
+	   image (i.e., symbols from all sections) in cost of increased kernel
+	   size (depending on the kernel configuration, it may be 300KiB or
+	   something like this).
+
+	   Say N unless you really need all symbols.
 
 config HOTPLUG
 	bool "Support for hot-pluggable devices" if EXPERT

scripts/.gitignore

@@ -8,3 +8,4 @@ bin2c
 unifdef
 ihex2fw
 recordmcount
+docproc

scripts/Kbuild.include

@@ -118,6 +118,11 @@ cc-option-yn = $(call try-run,\
 cc-option-align = $(subst -functions=0,,\
 	$(call cc-option,-falign-functions=0,-malign-functions=0))
 
+# cc-disable-warning
+# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
+cc-disable-warning = $(call try-run,\
+	$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -xc /dev/null -o "$$TMP",-Wno-$(strip $(1)))
+
 # cc-version
 # Usage gcc-ver := $(call cc-version)
 cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
@@ -141,6 +146,11 @@ cc-ldoption = $(call try-run,\
 ld-option = $(call try-run,\
 	$(CC) /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
 
+# ar-option
+# Usage: KBUILD_ARFLAGS := $(call ar-option,D)
+# Important: no spaces around options
+ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
+
 ######
 
 ###
@@ -187,6 +197,8 @@ ifneq ($(KBUILD_NOCMDDEP),1)
 # User may override this check using make KBUILD_NOCMDDEP=1
 arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
                     $(filter-out $(cmd_$@),   $(cmd_$(1))) )
+else
+arg-check = $(if $(strip $(cmd_$@)),,1)
 endif
 
 # >'< substitution is for echo to work,

scripts/Makefile

@@ -6,6 +6,7 @@
 # pnmttologo:    Convert pnm files to logo files
 # conmakehash:   Create chartable
 # conmakehash:	 Create arrays for initializing the kernel console tables
+# docproc:       Used in Documentation/DocBook
 
 hostprogs-$(CONFIG_KALLSYMS)     += kallsyms
 hostprogs-$(CONFIG_LOGO)         += pnmtologo
@@ -16,12 +17,14 @@ hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount
 always		:= $(hostprogs-y) $(hostprogs-m)
 
 # The following hostprogs-y programs are only build on demand
-hostprogs-y += unifdef
+hostprogs-y += unifdef docproc
 
-# This target is used internally to avoid "is up to date" messages
+# These targets are used internally to avoid "is up to date" messages
 PHONY += build_unifdef
 build_unifdef: scripts/unifdef FORCE
 	@:
+build_docproc: scripts/docproc FORCE
+	@:
 
 subdir-$(CONFIG_MODVERSIONS) += genksyms
 subdir-y                     += mod