From 71a83ec7da8910f374a1c82e96d2704aa45d9238 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Tue, 5 Apr 2011 13:24:57 +0300 Subject: [PATCH 01/20] Kconfig: improve KALLSYMS_ALL documentation Dumb users like myself are not able to grasp from the existing KALLSYMS_ALL documentation that this option is not what they need. Improve the help message and make it clearer that KALLSYMS is enough in the majority of use cases, and KALLSYMS_ALL should really be used very rarely. Signed-off-by: Artem Bityutskiy Signed-off-by: Michal Marek --- init/Kconfig | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/init/Kconfig b/init/Kconfig index 56240e724d9a..563065df29a5 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -968,12 +968,18 @@ 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. + 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). - Say N. + 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 KALLSYMS_EXTRA_PASS bool "Do an extra kallsyms pass" From 1e2795a1191bb5ff05e80d77feffd51ac875c06d Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Tue, 5 Apr 2011 13:24:58 +0300 Subject: [PATCH 02/20] kbuild: move KALLSYMS_EXTRA_PASS from Kconfig to Makefile At the moment we have the CONFIG_KALLSYMS_EXTRA_PASS Kconfig switch, which users can enable or disable while configuring the kernel. This option is then used by 'make' to determine whether an extra kallsyms pass is needed or not. However, this approach is not nice and confusing, and this patch moves CONFIG_KALLSYMS_EXTRA_PASS from Kconfig to Makefile instead. The rationale is below. 1. CONFIG_KALLSYMS_EXTRA_PASS is really about the build time, not run-time. There is no real need for it to be in Kconfig. It is just an additional work-around which should be used only in rare cases, when someone breaks kallsyms, so Kbuild/Makefile is much better place for this option. 2. Grepping CONFIG_KALLSYMS_EXTRA_PASS shows that many defconfigs have it enabled, probably not because they try to work-around a kallsyms bug, but just because the Kconfig help text is confusing and does not really make it clear that this option should not be used unless except when kallsyms is broken. 3. And since many people have CONFIG_KALLSYMS_EXTRA_PASS enabled in their Kconfig, we do might fail to notice kallsyms bugs in time. E.g., many testers use "make allyesconfig" to test builds, which will enable CONFIG_KALLSYMS_EXTRA_PASS and kallsyms breakage will not be noticed. To address that, this patch: 1. Kills CONFIG_KALLSYMS_EXTRA_PASS 2. Changes Makefile so that people can use "make KALLSYMS_EXTRA_PASS=1" to enable the extra pass if needed. Additionally, they may define KALLSYMS_EXTRA_PASS as an environment variable. 3. By default KALLSYMS_EXTRA_PASS is disabled and if kallsyms has issues, "make" should print a warning and suggest using KALLSYMS_EXTRA_PASS Signed-off-by: Artem Bityutskiy [mmarek: Removed make help text, is not necessary] Signed-off-by: Michal Marek --- Makefile | 13 ++++++++----- init/Kconfig | 12 ------------ 2 files changed, 8 insertions(+), 17 deletions(-) diff --git a/Makefile b/Makefile index ba7a55ccd890..c3bd316b16f4 100644 --- a/Makefile +++ b/Makefile @@ -797,15 +797,17 @@ 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 +818,8 @@ 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 diff --git a/init/Kconfig b/init/Kconfig index 563065df29a5..0edda616640f 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -981,18 +981,6 @@ config KALLSYMS_ALL Say N unless you really need all symbols. -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. - - config HOTPLUG bool "Support for hot-pluggable devices" if EXPERT default y From 6ae9ecb86188cc8419024cdb299f18d4ae4f5713 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 31 Mar 2011 15:47:55 +0200 Subject: [PATCH 03/20] kbuild: Call gzip with -n The timestamps recorded in the .gz files add no value. Signed-off-by: Michal Marek --- scripts/Makefile.lib | 2 +- scripts/gen_initramfs_list.sh | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 1c702ca8aac8..93b2b5938a2e 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -197,7 +197,7 @@ cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ # --------------------------------------------------------------------------- quiet_cmd_gzip = GZIP $@ -cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -f -9 > $@) || \ +cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \ (rm -f $@ ; false) # DTC diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh index 55caecdad995..4a43fe12d179 100644 --- a/scripts/gen_initramfs_list.sh +++ b/scripts/gen_initramfs_list.sh @@ -226,7 +226,7 @@ cpio_list= output="/dev/stdout" output_file="" is_cpio_compressed= -compr="gzip -9 -f" +compr="gzip -n -9 -f" arg="$1" case "$arg" in @@ -240,7 +240,7 @@ case "$arg" in output_file="$1" cpio_list="$(mktemp ${TMPDIR:-/tmp}/cpiolist.XXXXXX)" output=${cpio_list} - echo "$output_file" | grep -q "\.gz$" && compr="gzip -9 -f" + echo "$output_file" | grep -q "\.gz$" && compr="gzip -n -9 -f" echo "$output_file" | grep -q "\.bz2$" && compr="bzip2 -9 -f" echo "$output_file" | grep -q "\.lzma$" && compr="lzma -9 -f" echo "$output_file" | grep -q "\.xz$" && \ From 09ff9fecc039d60fff6c11d47522af61e89fff56 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 31 Mar 2011 16:09:47 +0200 Subject: [PATCH 04/20] kbuild: Use the deterministic mode of ar Signed-off-by: Michal Marek --- scripts/Makefile.build | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index d5f925abe4d2..5f87d3709f9f 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -345,7 +345,7 @@ quiet_cmd_link_o_target = LD $@ cmd_link_o_target = $(if $(strip $(obj-y)),\ $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \ $(cmd_secanalysis),\ - rm -f $@; $(AR) rcs $@) + rm -f $@; $(AR) rcsD $@) $(builtin-target): $(obj-y) FORCE $(call if_changed,link_o_target) @@ -371,7 +371,7 @@ $(modorder-target): $(subdir-ym) FORCE # ifdef lib-target quiet_cmd_link_l_target = AR $@ -cmd_link_l_target = rm -f $@; $(AR) rcs $@ $(lib-y) +cmd_link_l_target = rm -f $@; $(AR) rcsD $@ $(lib-y) $(lib-target): $(lib-y) FORCE $(call if_changed,link_l_target) From 061296dc2c14f852604fc6849669fe0b78bb1eda Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 31 Mar 2011 17:13:55 +0200 Subject: [PATCH 05/20] kbuild: Drop unused LINUX_COMPILE_TIME and LINUX_COMPILE_DOMAIN macros Signed-off-by: Michal Marek --- scripts/mkcompile_h | 16 ++-------------- 1 file changed, 2 insertions(+), 14 deletions(-) diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h index 50ad317a4bf9..82416a81df5e 100755 --- a/scripts/mkcompile_h +++ b/scripts/mkcompile_h @@ -63,21 +63,9 @@ UTS_TRUNCATE="cut -b -$UTS_LEN" echo \#define UTS_VERSION \"`echo $UTS_VERSION | $UTS_TRUNCATE`\" - echo \#define LINUX_COMPILE_TIME \"`date +%T`\" echo \#define LINUX_COMPILE_BY \"`whoami`\" echo \#define LINUX_COMPILE_HOST \"`hostname | $UTS_TRUNCATE`\" - domain=`dnsdomainname 2> /dev/null` - if [ -z "$domain" ]; then - domain=`domainname 2> /dev/null` - fi - - if [ -n "$domain" ]; then - echo \#define LINUX_COMPILE_DOMAIN \"`echo $domain | $UTS_TRUNCATE`\" - else - echo \#define LINUX_COMPILE_DOMAIN - fi - echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | tail -n 1`\" ) > .tmpcompile @@ -91,8 +79,8 @@ UTS_TRUNCATE="cut -b -$UTS_LEN" # first line. if [ -r $TARGET ] && \ - grep -v 'UTS_VERSION\|LINUX_COMPILE_TIME' $TARGET > .tmpver.1 && \ - grep -v 'UTS_VERSION\|LINUX_COMPILE_TIME' .tmpcompile > .tmpver.2 && \ + grep -v 'UTS_VERSION' $TARGET > .tmpver.1 && \ + grep -v 'UTS_VERSION' .tmpcompile > .tmpver.2 && \ cmp -s .tmpver.1 .tmpver.2; then rm -f .tmpcompile else From 53e6892c0411006848882eacfcfea9e93681b55d Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Tue, 5 Apr 2011 14:32:30 +0200 Subject: [PATCH 06/20] kbuild: Allow to override LINUX_COMPILE_BY and LINUX_COMPILE_HOST macros Make it possible to override the user@host string displayed during boot and in /proc/version by the environment variables KBUILD_BUILD_USER and KBUILD_BUILD_HOST. Several distributions patch scripts/mkcompile_h to achieve this, so let's provide an official way. Also, document the KBUILD_BUILD_TIMESTAMP variable while at it. Signed-off-by: Michal Marek --- Documentation/kbuild/kbuild.txt | 12 ++++++++++++ scripts/mkcompile_h | 14 ++++++++++++-- 2 files changed, 24 insertions(+), 2 deletions(-) diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index f1431d099fce..f11ebb33e4a6 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -201,3 +201,15 @@ 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 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. diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h index 82416a81df5e..7ad6bf7a09ff 100755 --- a/scripts/mkcompile_h +++ b/scripts/mkcompile_h @@ -42,6 +42,16 @@ if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then else TIMESTAMP=$KBUILD_BUILD_TIMESTAMP fi +if test -z "$KBUILD_BUILD_USER"; then + LINUX_COMPILE_BY=`whoami` +else + LINUX_COMPILE_BY=$KBUILD_BUILD_USER +fi +if test -z "$KBUILD_BUILD_HOST"; then + LINUX_COMPILE_HOST=`hostname` +else + LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST +fi UTS_VERSION="#$VERSION" CONFIG_FLAGS="" @@ -63,8 +73,8 @@ UTS_TRUNCATE="cut -b -$UTS_LEN" echo \#define UTS_VERSION \"`echo $UTS_VERSION | $UTS_TRUNCATE`\" - echo \#define LINUX_COMPILE_BY \"`whoami`\" - echo \#define LINUX_COMPILE_HOST \"`hostname | $UTS_TRUNCATE`\" + echo \#define LINUX_COMPILE_BY \"`echo $LINUX_COMPILE_BY | $UTS_TRUNCATE`\" + echo \#define LINUX_COMPILE_HOST \"`echo $LINUX_COMPILE_HOST | $UTS_TRUNCATE`\" echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | tail -n 1`\" ) > .tmpcompile From a8b8017c34fefcb763d8b06c294b58d1c480b2e4 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 31 Mar 2011 23:16:42 +0200 Subject: [PATCH 07/20] initramfs: Use KBUILD_BUILD_TIMESTAMP for generated entries gen_init_cpio gets the current time and uses it for each symlink, special file, and directory. Grab the current time once and make it possible to override it with the KBUILD_BUILD_TIMESTAMP variable for reproducible builds. Signed-off-by: Michal Marek --- Documentation/kbuild/kbuild.txt | 3 +- scripts/gen_initramfs_list.sh | 9 +++++- usr/gen_init_cpio.c | 53 +++++++++++++++++++++++++-------- 3 files changed, 50 insertions(+), 15 deletions(-) diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index f11ebb33e4a6..646e2c114fff 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -205,7 +205,8 @@ 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 default value +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 diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh index 4a43fe12d179..d44cf675bc22 100644 --- a/scripts/gen_initramfs_list.sh +++ b/scripts/gen_initramfs_list.sh @@ -287,8 +287,15 @@ done # we are carefull to delete tmp files if [ ! -z ${output_file} ]; then if [ -z ${cpio_file} ]; then + timestamp= + if test -n "$KBUILD_BUILD_TIMESTAMP"; then + timestamp="$(date -d"$KBUILD_BUILD_TIMESTAMP" +%s || :)" + if test -n "$timestamp"; then + timestamp="-t $timestamp" + fi + fi cpio_tfile="$(mktemp ${TMPDIR:-/tmp}/cpiofile.XXXXXX)" - usr/gen_init_cpio ${cpio_list} > ${cpio_tfile} + usr/gen_init_cpio $timestamp ${cpio_list} > ${cpio_tfile} else cpio_tfile=${cpio_file} fi diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c index 7f06884ecd41..af0f22fb1ef7 100644 --- a/usr/gen_init_cpio.c +++ b/usr/gen_init_cpio.c @@ -22,6 +22,7 @@ static unsigned int offset; static unsigned int ino = 721; +static time_t default_mtime; struct file_handler { const char *type; @@ -102,7 +103,6 @@ static int cpio_mkslink(const char *name, const char *target, unsigned int mode, uid_t uid, gid_t gid) { char s[256]; - time_t mtime = time(NULL); if (name[0] == '/') name++; @@ -114,7 +114,7 @@ static int cpio_mkslink(const char *name, const char *target, (long) uid, /* uid */ (long) gid, /* gid */ 1, /* nlink */ - (long) mtime, /* mtime */ + (long) default_mtime, /* mtime */ (unsigned)strlen(target)+1, /* filesize */ 3, /* major */ 1, /* minor */ @@ -152,7 +152,6 @@ static int cpio_mkgeneric(const char *name, unsigned int mode, uid_t uid, gid_t gid) { char s[256]; - time_t mtime = time(NULL); if (name[0] == '/') name++; @@ -164,7 +163,7 @@ static int cpio_mkgeneric(const char *name, unsigned int mode, (long) uid, /* uid */ (long) gid, /* gid */ 2, /* nlink */ - (long) mtime, /* mtime */ + (long) default_mtime, /* mtime */ 0, /* filesize */ 3, /* major */ 1, /* minor */ @@ -242,7 +241,6 @@ static int cpio_mknod(const char *name, unsigned int mode, unsigned int maj, unsigned int min) { char s[256]; - time_t mtime = time(NULL); if (dev_type == 'b') mode |= S_IFBLK; @@ -259,7 +257,7 @@ static int cpio_mknod(const char *name, unsigned int mode, (long) uid, /* uid */ (long) gid, /* gid */ 1, /* nlink */ - (long) mtime, /* mtime */ + (long) default_mtime, /* mtime */ 0, /* filesize */ 3, /* major */ 1, /* minor */ @@ -460,7 +458,7 @@ static int cpio_mkfile_line(const char *line) static void usage(const char *prog) { fprintf(stderr, "Usage:\n" - "\t%s \n" + "\t%s [-t ] \n" "\n" " is a file containing newline separated entries that\n" "describe the files to be included in the initramfs archive:\n" @@ -491,7 +489,11 @@ static void usage(const char *prog) "nod /dev/console 0600 0 0 c 5 1\n" "dir /root 0700 0 0\n" "dir /sbin 0755 0 0\n" - "file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n", + "file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n" + "\n" + " is time in seconds since Epoch that will be used\n" + "as mtime for symlinks, special files and directories. The default\n" + "is to use the current time for these entries.\n", prog); } @@ -529,17 +531,42 @@ int main (int argc, char *argv[]) char *args, *type; int ec = 0; int line_nr = 0; + const char *filename; - if (2 != argc) { + default_mtime = time(NULL); + while (1) { + int opt = getopt(argc, argv, "t:h"); + char *invalid; + + if (opt == -1) + break; + switch (opt) { + case 't': + default_mtime = strtol(optarg, &invalid, 10); + if (!*optarg || *invalid) { + fprintf(stderr, "Invalid timestamp: %s\n", + optarg); + usage(argv[0]); + exit(1); + } + break; + case 'h': + case '?': + usage(argv[0]); + exit(opt == 'h' ? 0 : 1); + } + } + + if (argc - optind != 1) { usage(argv[0]); exit(1); } - - if (!strcmp(argv[1], "-")) + filename = argv[optind]; + if (!strcmp(filename, "-")) cpio_list = stdin; - else if (! (cpio_list = fopen(argv[1], "r"))) { + else if (!(cpio_list = fopen(filename, "r"))) { fprintf(stderr, "ERROR: unable to open '%s': %s\n\n", - argv[1], strerror(errno)); + filename, strerror(errno)); usage(argv[0]); exit(1); } From 40df759e2b9ec945f1a5ddc61b3fdfbb6583257e Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Wed, 20 Apr 2011 13:45:30 +0200 Subject: [PATCH 08/20] kbuild: Fix build with binutils <= 2.19 The D option of ar is only available in newer versions. Signed-off-by: Michal Marek --- Documentation/kbuild/makefiles.txt | 5 +++++ Makefile | 4 ++++ scripts/Kbuild.include | 5 +++++ scripts/Makefile.build | 4 ++-- 4 files changed, 16 insertions(+), 2 deletions(-) diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 5d145bb443c0..40e082bb8c52 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -955,6 +955,11 @@ 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 diff --git a/Makefile b/Makefile index c3bd316b16f4..d7c42319fe1e 100644 --- a/Makefile +++ b/Makefile @@ -382,6 +382,7 @@ 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 @@ -612,6 +613,9 @@ 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 diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index ed2773edfe71..fae2d8d8cb09 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -141,6 +141,11 @@ 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)) + ###### ### diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 5f87d3709f9f..e1244ef308ce 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -345,7 +345,7 @@ quiet_cmd_link_o_target = LD $@ cmd_link_o_target = $(if $(strip $(obj-y)),\ $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \ $(cmd_secanalysis),\ - rm -f $@; $(AR) rcsD $@) + rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@) $(builtin-target): $(obj-y) FORCE $(call if_changed,link_o_target) @@ -371,7 +371,7 @@ $(modorder-target): $(subdir-ym) FORCE # ifdef lib-target quiet_cmd_link_l_target = AR $@ -cmd_link_l_target = rm -f $@; $(AR) rcsD $@ $(lib-y) +cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y) $(lib-target): $(lib-y) FORCE $(call if_changed,link_l_target) From 28bc20dccadc610c56e27255aeef2938141a0cd3 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Wed, 27 Apr 2011 22:15:27 +0200 Subject: [PATCH 09/20] kbuild: implement several W= levels Building a kernel with "make W=1" produces far too much noise to be useful. Divide the warning options in three groups: W=1 - warnings that may be relevant and does not occur too often W=2 - warnings that occur quite often but may still be relevant W=3 - the more obscure warnings, can most likely be ignored When building the whole kernel, those levels produce: W=1 - 4859 warnings W=2 - 1394 warnings W=3 - 86666 warnings respectively. Warnings have been counted with Geert's script at http://www.kernel.org/pub/linux/kernel/people/geert/linux-log/linux-log-summary.pl Many warnings occur from .h files so fixing one file may have a nice effect on the total number of warnings. With these changes I am actually tempted to try W=1 now and then. Previously there was just too much noise. Borislav: - make the W= levels exclusive - move very noisy and making little sense for the kernel warnings to W=3 - drop -Woverlength-strings due to useless warning message - copy explanatory text for the different warning levels to 'make help' - recount warnings per level Signed-off-by: Sam Ravnborg Signed-off-by: Borislav Petkov Cc: Dave Jones Cc: Geert Uytterhoeven Signed-off-by: Michal Marek --- Makefile | 8 ++++-- scripts/Makefile.build | 65 ++++++++++++++++++++++++------------------ 2 files changed, 44 insertions(+), 29 deletions(-) diff --git a/Makefile b/Makefile index d7c42319fe1e..d43429f4ced8 100644 --- a/Makefile +++ b/Makefile @@ -103,7 +103,7 @@ ifeq ("$(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 @@ -1274,7 +1274,11 @@ 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 '' @echo 'Execute "make" or "make all" to build all targets marked with [*] ' @echo 'For further info see the ./README file' diff --git a/scripts/Makefile.build b/scripts/Makefile.build index e1244ef308ce..9c0c48127946 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -51,36 +51,47 @@ ifeq ($(KBUILD_NOPEDANTIC),) endif # -# make W=1 settings +# make W=... settings # -# $(call cc-option... ) handles gcc -W.. options which +# W=1 - warnings that may be relevant and does not occur too often +# W=2 - warnings that occur quite often but may still be relevant +# W=3 - the more obscure warnings, can most likely be ignored +# +# $(call cc-option, -W...) handles gcc -W.. options which # are not supported by all versions of the compiler ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS -KBUILD_EXTRA_WARNINGS := -Wextra -KBUILD_EXTRA_WARNINGS += -Wunused -Wno-unused-parameter -KBUILD_EXTRA_WARNINGS += -Waggregate-return -KBUILD_EXTRA_WARNINGS += -Wbad-function-cast -KBUILD_EXTRA_WARNINGS += -Wcast-qual -KBUILD_EXTRA_WARNINGS += -Wcast-align -KBUILD_EXTRA_WARNINGS += -Wconversion -KBUILD_EXTRA_WARNINGS += -Wdisabled-optimization -KBUILD_EXTRA_WARNINGS += -Wlogical-op -KBUILD_EXTRA_WARNINGS += -Wmissing-declarations -KBUILD_EXTRA_WARNINGS += -Wmissing-format-attribute -KBUILD_EXTRA_WARNINGS += $(call cc-option, -Wmissing-include-dirs,) -KBUILD_EXTRA_WARNINGS += -Wmissing-prototypes -KBUILD_EXTRA_WARNINGS += -Wnested-externs -KBUILD_EXTRA_WARNINGS += -Wold-style-definition -KBUILD_EXTRA_WARNINGS += $(call cc-option, -Woverlength-strings,) -KBUILD_EXTRA_WARNINGS += -Wpacked -KBUILD_EXTRA_WARNINGS += -Wpacked-bitfield-compat -KBUILD_EXTRA_WARNINGS += -Wpadded -KBUILD_EXTRA_WARNINGS += -Wpointer-arith -KBUILD_EXTRA_WARNINGS += -Wredundant-decls -KBUILD_EXTRA_WARNINGS += -Wshadow -KBUILD_EXTRA_WARNINGS += -Wswitch-default -KBUILD_EXTRA_WARNINGS += $(call cc-option, -Wvla,) -KBUILD_CFLAGS += $(KBUILD_EXTRA_WARNINGS) +warning-1 := -Wextra -Wunused -Wno-unused-parameter +warning-1 += -Wmissing-declarations +warning-1 += -Wmissing-format-attribute +warning-1 += -Wmissing-prototypes +warning-1 += -Wold-style-definition +warning-1 += $(call cc-option, -Wmissing-include-dirs) + +warning-2 := -Waggregate-return +warning-2 += -Wcast-align +warning-2 += -Wdisabled-optimization +warning-2 += -Wnested-externs +warning-2 += -Wshadow +warning-2 += $(call cc-option, -Wlogical-op) + +warning-3 := -Wbad-function-cast +warning-3 += -Wcast-qual +warning-3 += -Wconversion +warning-3 += -Wpacked +warning-3 += -Wpadded +warning-3 += -Wpointer-arith +warning-3 += -Wredundant-decls +warning-3 += -Wswitch-default +warning-3 += $(call cc-option, -Wpacked-bitfield-compat) +warning-3 += $(call cc-option, -Wvla) + +warning := $(warning-$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)) + +ifeq ("$(warning)","") + $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown) +endif + +KBUILD_CFLAGS += $(warning) endif include scripts/Makefile.lib From d8ecc5cd8e227bc318513b5306ae88a474b8886d Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Wed, 27 Apr 2011 22:29:49 +0200 Subject: [PATCH 10/20] kbuild: asm-generic support There is an increasing amount of header files shared between individual architectures in asm-generic. To avoid a lot of dummy wrapper files that just include the corresponding file in asm-generic provide some basic support in kbuild for this. With the following patch an architecture can maintain a list of files in the file arch/$(ARCH)/include/asm/Kbuild To use a generic file just add: generic-y += For each file listed kbuild will generate the necessary wrapper in arch/$(ARCH)/include/generated/asm. When installing userspace headers a wrapper is likewise created. The original inspiration for this came from the unicore32 patchset - although a different method is used. The patch includes several improvements from Arnd Bergmann. Michael Marek contributed Makefile.asm-generic. Remis Baima did an intial implementation along to achive the same - see https://patchwork.kernel.org/patch/13352/ Signed-off-by: Sam Ravnborg Acked-by: Guan Xuetao Tested-by: Guan Xuetao Acked-by: Arnd Bergmann Cc: Remis Lima Baima Signed-off-by: Michal Marek --- .gitignore | 1 + Documentation/kbuild/makefiles.txt | 36 ++++++++++++++++++++++++++++++ Makefile | 16 +++++++++---- scripts/Makefile.asm-generic | 23 +++++++++++++++++++ scripts/Makefile.headersinst | 10 ++++++++- 5 files changed, 81 insertions(+), 5 deletions(-) create mode 100644 scripts/Makefile.asm-generic diff --git a/.gitignore b/.gitignore index 5d56a3fd0de6..9dacde0a4b2d 100644 --- a/.gitignore +++ b/.gitignore @@ -57,6 +57,7 @@ modules.builtin include/config include/linux/version.h include/generated +arch/*/include/generated # stgit generated dirs patches-* diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 40e082bb8c52..835b64acf0b4 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/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 @@ -1214,6 +1216,14 @@ 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. @@ -1270,6 +1280,32 @@ 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/$(ARCH)/include/generated/asm + + When a header is exported where the architecture uses + the generic header a similar wrapper is generated as part + of the set of exported headers in the directory: + + usr/include/asm + + The generated wrapper will in both cases look like the following: + + Example: termios.h + #include === 8 Kbuild Variables diff --git a/Makefile b/Makefile index d43429f4ced8..e509cc704968 100644 --- a/Makefile +++ b/Makefile @@ -349,7 +349,8 @@ CFLAGS_GCOV = -fprofile-arcs -ftest-coverage # Use LINUXINCLUDE when you must reference the include/ directory. # Needed to be compatible with the O= option -LINUXINCLUDE := -I$(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 @@ -417,6 +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 @@ -954,7 +961,7 @@ 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 @@ -1028,7 +1035,7 @@ 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) $(build)=scripts build_unifdef PHONY += headers_install_all @@ -1143,7 +1150,8 @@ CLEAN_FILES += vmlinux System.map \ .tmp_kallsyms* .tmp_version .tmp_vmlinux* .tmp_System.map # Directories & files removed with 'make mrproper' -MRPROPER_DIRS += include/config usr/include include/generated +MRPROPER_DIRS += include/config usr/include include/generated \ + arch/*/include/generated MRPROPER_FILES += .config .config.old .version .old_version \ include/linux/version.h \ Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS diff --git a/scripts/Makefile.asm-generic b/scripts/Makefile.asm-generic new file mode 100644 index 000000000000..a687cb697e35 --- /dev/null +++ b/scripts/Makefile.asm-generic @@ -0,0 +1,23 @@ +# include/asm-generic contains a lot of files that are used +# verbatim by several architectures. +# +# This Makefile reads the file arch/$(SRCARCH)/include/asm/Kbuild +# and for each file listed in this file with generic-y creates +# a small wrapper file in $(obj) (arch/$(SRCARCH)/include/generated/asm) + +kbuild-file := $(srctree)/arch/$(SRCARCH)/include/asm/Kbuild +include $(kbuild-file) + +include scripts/Kbuild.include + +# Create output directory if not already present +_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj)) + +quiet_cmd_wrap = WRAP $@ +cmd_wrap = echo "\#include " >$@ + +all: $(patsubst %, $(obj)/%, $(generic-y)) + +$(obj)/%.h: + $(call cmd,wrap) + diff --git a/scripts/Makefile.headersinst b/scripts/Makefile.headersinst index f89cb87f5c01..a57f5bd5a13d 100644 --- a/scripts/Makefile.headersinst +++ b/scripts/Makefile.headersinst @@ -27,8 +27,13 @@ header-y := $(filter-out %/, $(header-y)) install-file := $(install)/.install check-file := $(install)/.check +# generic-y list all files an architecture uses from asm-generic +# Use this to build a list of headers which require a wrapper +wrapper-files := $(filter $(header-y), $(generic-y)) + # all headers files for this dir -all-files := $(header-y) $(objhdr-y) +header-y := $(filter-out $(generic-y), $(header-y)) +all-files := $(header-y) $(objhdr-y) $(wrapper-files) input-files := $(addprefix $(srctree)/$(obj)/,$(header-y)) \ $(addprefix $(objtree)/$(obj)/,$(objhdr-y)) output-files := $(addprefix $(install)/, $(all-files)) @@ -47,6 +52,9 @@ quiet_cmd_install = INSTALL $(printdir) ($(words $(all-files))\ cmd_install = \ $(PERL) $< $(srctree)/$(obj) $(install) $(SRCARCH) $(header-y); \ $(PERL) $< $(objtree)/$(obj) $(install) $(SRCARCH) $(objhdr-y); \ + for F in $(wrapper-files); do \ + echo "\#include " > $(install)/$$F; \ + done; \ touch $@ quiet_cmd_remove = REMOVE $(unwanted) From f07726048d599acd6bac438e304645a78db753c0 Mon Sep 17 00:00:00 2001 From: Marcin Nowakowski Date: Mon, 25 Apr 2011 13:35:21 +0100 Subject: [PATCH 11/20] Fix handling of backlash character in LINUX_COMPILE_BY name When using a domain login, `whoami` returns the login in user\domain format. This leads to either warnings on unrecognised escape sequences or escaped characters being generated for the user. This patch ensures that any backslash is escaped to a double-backslash to make sure the name is preserved correctly. This patch does not enforce escaping on the KBUILD_BUILD_USER variable, as this is something the user has control of and can escape if required. Signed-off-by: Marcin Nowakowski Signed-off-by: Michal Marek --- scripts/mkcompile_h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h index 7ad6bf7a09ff..f221ddf69080 100755 --- a/scripts/mkcompile_h +++ b/scripts/mkcompile_h @@ -43,7 +43,7 @@ else TIMESTAMP=$KBUILD_BUILD_TIMESTAMP fi if test -z "$KBUILD_BUILD_USER"; then - LINUX_COMPILE_BY=`whoami` + LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/') else LINUX_COMPILE_BY=$KBUILD_BUILD_USER fi From af0e5d565d2fffcd97d1e2d89669d627cc04e8b8 Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Thu, 21 Apr 2011 17:28:13 -0400 Subject: [PATCH 12/20] kbuild: Disable -Wunused-but-set-variable for gcc 4.6.0 Disable the new -Wunused-but-set-variable that was added in gcc 4.6.0 It produces more false positives than useful warnings. This can still be enabled using W=1 Signed-off-by: Dave Jones Acked-by: Sam Ravnborg Tested-by: Sam Ravnborg Signed-off-by: Michal Marek --- Makefile | 4 ++++ scripts/Makefile.build | 1 + 2 files changed, 5 insertions(+) diff --git a/Makefile b/Makefile index e509cc704968..4527dc23a724 100644 --- a/Makefile +++ b/Makefile @@ -567,6 +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-option, -Wno-unused-but-set-variable) + ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls else diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 9c0c48127946..9fb19c0fbf8c 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -66,6 +66,7 @@ warning-1 += -Wmissing-format-attribute warning-1 += -Wmissing-prototypes warning-1 += -Wold-style-definition warning-1 += $(call cc-option, -Wmissing-include-dirs) +warning-1 += $(call cc-option, -Wunused-but-set-variable) warning-2 := -Waggregate-return warning-2 += -Wcast-align From a6de553da01c2c110c647fbd1c5bad29f5a82487 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Fri, 29 Apr 2011 14:45:31 +0200 Subject: [PATCH 13/20] kbuild: Allow to combine multiple W= levels Add support for make W=12, make W=123 and so on, to enable warnings from multiple W= levels. Normally, make W= does not include warnings from the previous level. Signed-off-by: Michal Marek Acked-by: Sam Ravnborg Reviewed-By: Valdis Kletnieks --- Makefile | 2 +- scripts/Makefile.build | 8 ++++++-- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/Makefile b/Makefile index 4527dc23a724..d34250266f47 100644 --- a/Makefile +++ b/Makefile @@ -1290,7 +1290,7 @@ help: @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 '' @echo 'Execute "make" or "make all" to build all targets marked with [*] ' @echo 'For further info see the ./README file' diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 9fb19c0fbf8c..f133641f815a 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -60,6 +60,8 @@ endif # $(call cc-option, -W...) handles gcc -W.. options which # are not supported by all versions of the compiler ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS +warning- := $(empty) + warning-1 := -Wextra -Wunused -Wno-unused-parameter warning-1 += -Wmissing-declarations warning-1 += -Wmissing-format-attribute @@ -86,9 +88,11 @@ warning-3 += -Wswitch-default warning-3 += $(call cc-option, -Wpacked-bitfield-compat) warning-3 += $(call cc-option, -Wvla) -warning := $(warning-$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)) +warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) +warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) +warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) -ifeq ("$(warning)","") +ifeq ("$(strip $(warning))","") $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown) endif From 7a04fc94d9e45de50827ba6ff764f22990d55823 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Mon, 2 May 2011 18:01:06 +0200 Subject: [PATCH 14/20] kbuild: Fix Makefile.asm-generic for um Do nothing if arch/$(SRCARCH)/include/asm/Kbuild does not exist, which is the case of um. Reported-by: Randy Dunlap Signed-off-by: Michal Marek Acked-by: Randy Dunlap Acked-by: Sam Ravnborg --- scripts/Makefile.asm-generic | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/Makefile.asm-generic b/scripts/Makefile.asm-generic index a687cb697e35..490122c3e2aa 100644 --- a/scripts/Makefile.asm-generic +++ b/scripts/Makefile.asm-generic @@ -6,7 +6,7 @@ # a small wrapper file in $(obj) (arch/$(SRCARCH)/include/generated/asm) kbuild-file := $(srctree)/arch/$(SRCARCH)/include/asm/Kbuild -include $(kbuild-file) +-include $(kbuild-file) include scripts/Kbuild.include From bffd2020a972a188750e5cf4b9566950dfdf25a2 Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Mon, 2 May 2011 22:48:03 +0200 Subject: [PATCH 15/20] kbuild: move scripts/basic/docproc.c to scripts/docproc.c Move docproc from scripts/basic to scripts so it is only built for *doc targets instead of every time the kernel is built. --- Documentation/DocBook/Makefile | 2 +- Makefile | 1 + scripts/.gitignore | 1 + scripts/Makefile | 7 +++++-- scripts/basic/.gitignore | 2 -- scripts/basic/Makefile | 3 +-- scripts/{basic => }/docproc.c | 0 7 files changed, 9 insertions(+), 7 deletions(-) rename scripts/{basic => }/docproc.c (100%) diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile index 8436b018c289..3cebfa0d1611 100644 --- a/Documentation/DocBook/Makefile +++ b/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 diff --git a/Makefile b/Makefile index d34250266f47..bc9eae424af8 100644 --- a/Makefile +++ b/Makefile @@ -1313,6 +1313,7 @@ $(help-board-dirs): help-%: # Documentation targets # --------------------------------------------------------------------------- %docs: scripts_basic FORCE + $(Q)$(MAKE) $(build)=scripts build_docproc $(Q)$(MAKE) $(build)=Documentation/DocBook $@ else # KBUILD_EXTMOD diff --git a/scripts/.gitignore b/scripts/.gitignore index e2741d23bab8..105b21f08185 100644 --- a/scripts/.gitignore +++ b/scripts/.gitignore @@ -8,3 +8,4 @@ bin2c unifdef ihex2fw recordmcount +docproc diff --git a/scripts/Makefile b/scripts/Makefile index fcea26168bca..df7678febf27 100644 --- a/scripts/Makefile +++ b/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 diff --git a/scripts/basic/.gitignore b/scripts/basic/.gitignore index bf8b199ec598..a776371a3502 100644 --- a/scripts/basic/.gitignore +++ b/scripts/basic/.gitignore @@ -1,3 +1 @@ -hash fixdep -docproc diff --git a/scripts/basic/Makefile b/scripts/basic/Makefile index 4c324a1f1e0e..4fcef87bb875 100644 --- a/scripts/basic/Makefile +++ b/scripts/basic/Makefile @@ -7,9 +7,8 @@ # .config is included by main Makefile. # --------------------------------------------------------------------------- # fixdep: Used to generate dependency information during build process -# docproc: Used in Documentation/DocBook -hostprogs-y := fixdep docproc +hostprogs-y := fixdep always := $(hostprogs-y) # fixdep is needed to compile other host programs diff --git a/scripts/basic/docproc.c b/scripts/docproc.c similarity index 100% rename from scripts/basic/docproc.c rename to scripts/docproc.c From 8417da6f2128008c431c7d130af6cd3d9079922e Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Mon, 2 May 2011 12:51:15 +0200 Subject: [PATCH 16/20] kbuild: Fix passing -Wno-* options to gcc 4.4+ Starting with 4.4, gcc will happily accept -Wno- in the cc-option test and complain later when compiling a file that has some other warning. This rather unexpected behavior is intentional as per http://gcc.gnu.org/PR28322, so work around it by testing for support of the opposite option (without the no-). Introduce a new Makefile function cc-disable-warning that does this and update two uses of cc-option in the toplevel Makefile. Reported-and-tested-by: Stephen Rothwell Signed-off-by: Michal Marek --- Documentation/kbuild/makefiles.txt | 12 ++++++++++++ Makefile | 4 ++-- scripts/Kbuild.include | 5 +++++ 3 files changed, 19 insertions(+), 2 deletions(-) diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 835b64acf0b4..47435e56c5da 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -501,6 +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 where both are two digits. So for example diff --git a/Makefile b/Makefile index bc9eae424af8..5cf4eb03fb3e 100644 --- a/Makefile +++ b/Makefile @@ -569,7 +569,7 @@ 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-option, -Wno-unused-but-set-variable) +KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable) ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls @@ -616,7 +616,7 @@ 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) diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index fae2d8d8cb09..c034dd7161a6 100644 --- a/scripts/Kbuild.include +++ b/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 $(CC)) From 43f67c98161c65f1b2e3af3a9ce6741850072c06 Mon Sep 17 00:00:00 2001 From: Kevin Cernekee Date: Tue, 10 May 2011 15:47:16 -0700 Subject: [PATCH 17/20] kbuild: Fix GNU make v3.80 compatibility According to Documentation/Changes, the kernel should be buildable with GNU make 3.80+. Commit 88d7be031f9f975bb3f50a0b5ef3796a671e7edf (kbuild: Use a single clean rule for kernel and external modules) introduced the "$(or" construct, which requires make 3.81. This causes "make clean" to malfunction when it is used with external modules. Replace "$(or" with an equivalent "$(if" expression, to restore backward compatibility. Signed-off-by: Kevin Cernekee Cc: stable@kernel.org Signed-off-by: Michal Marek --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 5cf4eb03fb3e..d96f56e1bfcd 100644 --- a/Makefile +++ b/Makefile @@ -1398,7 +1398,7 @@ 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' \ From 153f01147065cb3628493dcb79417bc4474320c7 Mon Sep 17 00:00:00 2001 From: Jamey Sharp Date: Thu, 5 May 2011 12:03:47 -0700 Subject: [PATCH 18/20] scripts/gen_initramfs_list.sh: Convert to a /bin/sh script Replace bashisms with POSIX-compatible shell scripting. Notably, de-duplicate '/' using a sed command from elsewhere in the same script rather than "${name//\/\///}". Commit by Jamey Sharp and Josh Triplett. Signed-off-by: Jamey Sharp Signed-off-by: Josh Triplett Cc: Andrew Morton Signed-off-by: Michal Marek --- scripts/gen_initramfs_list.sh | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh index d44cf675bc22..8da7890310d6 100644 --- a/scripts/gen_initramfs_list.sh +++ b/scripts/gen_initramfs_list.sh @@ -1,4 +1,4 @@ -#!/bin/bash +#!/bin/sh # Copyright (C) Martin Schlemmer # Copyright (C) 2006 Sam Ravnborg # @@ -105,9 +105,9 @@ list_parse() { # for links, devices etc the format differs. See gen_init_cpio for details parse() { local location="$1" - local name="${location/${srcdir}//}" + local name="/${location#${srcdir}}" # change '//' into '/' - name="${name//\/\///}" + name=$(echo "$name" | sed -e 's://*:/:g') local mode="$2" local uid="$3" local gid="$4" @@ -117,8 +117,8 @@ parse() { [ "$root_gid" = "squash" ] && gid=0 || [ "$gid" -eq "$root_gid" ] && gid=0 local str="${mode} ${uid} ${gid}" - [ "${ftype}" == "invalid" ] && return 0 - [ "${location}" == "${srcdir}" ] && return 0 + [ "${ftype}" = "invalid" ] && return 0 + [ "${location}" = "${srcdir}" ] && return 0 case "${ftype}" in "file") @@ -192,7 +192,7 @@ input_file() { if [ -f "$1" ]; then ${dep_list}header "$1" is_cpio="$(echo "$1" | sed 's/^.*\.cpio\(\..*\)\?/cpio/')" - if [ $2 -eq 0 -a ${is_cpio} == "cpio" ]; then + if [ $2 -eq 0 -a ${is_cpio} = "cpio" ]; then cpio_file=$1 echo "$1" | grep -q '^.*\.cpio\..*' && is_cpio_compressed="compressed" [ ! -z ${dep_list} ] && echo "$1" @@ -204,7 +204,7 @@ input_file() { else echo "$1 \\" cat "$1" | while read type dir file perm ; do - if [ "$type" == "file" ]; then + if [ "$type" = "file" ]; then echo "$file \\"; fi done From e0a04b11e4059cab033469617c2a3ce2d8cab416 Mon Sep 17 00:00:00 2001 From: Xiaochen Wang Date: Sun, 1 May 2011 11:41:41 +0800 Subject: [PATCH 19/20] scripts/kallsyms.c: fix potential segfault Description: This bug hardly appears during real kernel compiling, because the vmlinux symbols table is huge. But we can still catch it under strict condition , as follows. $ echo "c101b97b T do_fork" | ./scripts/kallsyms --all-symbols #include ...... ...... .globl kallsyms_token_table ALGN kallsyms_token_table: Segmentation fault (core dumped) $ If symbols table is small, all entries in token_profit[0x10000] may decrease to 0 after several calls of compress_symbols() in optimize_result(). In that case, find_best_token() always return 0 and best_table[i] is set to "\0\0" and best_table_len[i] is set to 2. As a result, expand_symbol(best_table[0]="\0\0", best_table_len[0]=2, buf) in write_src() will run in infinite recursion until stack overflows, causing segfault. This patch checks the find_best_token() return value. If all entries in token_profit[0x10000] become 0 according to return value, it breaks the loop in optimize_result(). And expand_symbol() works well when best_table_len[i] is 0. Signed-off-by: Xiaochen Wang Acked-by: Paulo Marques Signed-off-by: Michal Marek --- scripts/kallsyms.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 60dd3eb9366e..487ac6f37ca2 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -500,6 +500,8 @@ static void optimize_result(void) /* find the token with the breates profit value */ best = find_best_token(); + if (token_profit[best] == 0) + break; /* place it in the "best" table */ best_table_len[i] = 2; From c4d5ee13984f57b2f881635c49045151679f5e8a Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Mon, 16 May 2011 16:37:34 +0200 Subject: [PATCH 20/20] kbuild: make KBUILD_NOCMDDEP=1 handle empty built-in.o Based on a patch by Rabin Vincent. Fix building with KBUILD_NOCMDDEP=1, which currently does not work because it does not build built-in.o with no dependencies: LD fs/notify/built-in.o ld: cannot find fs/notify/dnotify/built-in.o: No such file or directory ld: cannot find fs/notify/inotify/built-in.o: No such file or directory ld: cannot find fs/notify/fanotify/built-in.o: No such file or directory Reported-and-tested-by: Rabin Vincent Signed-off-by: Michal Marek --- scripts/Kbuild.include | 2 ++ 1 file changed, 2 insertions(+) diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index c034dd7161a6..be39cd1c74cf 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -197,6 +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,