From da541b20021c781f8b65492eeaee824e729599eb Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 27 Sep 2017 17:34:23 -0500 Subject: objtool: Skip unreachable warnings for GCC 4.4 and older The kbuild bot occasionally reports warnings like: drivers/scsi/pcmcia/aha152x_core.o: warning: objtool: seldo_run()+0x130: unreachable instruction These warnings are always with GCC 4.4. That version of GCC sometimes places unreachable instructions after calls to noreturn functions. The unreachable warnings aren't very important anyway. Just ignore them for old versions of GCC. Reported-by: kbuild test robot Signed-off-by: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/bc89b807d965b98ec18a0bb94f96a594bd58f2f2.1506551639.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- scripts/Makefile.build | 2 ++ 1 file changed, 2 insertions(+) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 2e3a10e79ca9..061d0c3a420a 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -265,6 +265,8 @@ objtool_args += --no-fp endif ifdef CONFIG_GCOV_KERNEL objtool_args += --no-unreachable +else +objtool_args += $(call cc-ifversion, -lt, 0405, --no-unreachable) endif # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory -- cgit v1.2.3 From 11af847446ed0d131cf24d16a7ef3d5ea7a49554 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Fri, 13 Oct 2017 15:02:00 -0500 Subject: x86/unwind: Rename unwinder config options to 'CONFIG_UNWINDER_*' Rename the unwinder config options from: CONFIG_ORC_UNWINDER CONFIG_FRAME_POINTER_UNWINDER CONFIG_GUESS_UNWINDER to: CONFIG_UNWINDER_ORC CONFIG_UNWINDER_FRAME_POINTER CONFIG_UNWINDER_GUESS ... in order to give them a more logical config namespace. Suggested-by: Ingo Molnar Signed-off-by: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/73972fc7e2762e91912c6b9584582703d6f1b8cc.1507924831.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- scripts/Makefile.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 061d0c3a420a..f965f477832e 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -258,7 +258,7 @@ ifneq ($(SKIP_STACK_VALIDATION),1) __objtool_obj := $(objtree)/tools/objtool/objtool -objtool_args = $(if $(CONFIG_ORC_UNWINDER),orc generate,check) +objtool_args = $(if $(CONFIG_UNWINDER_ORC),orc generate,check) ifndef CONFIG_FRAME_POINTER objtool_args += --no-fp -- cgit v1.2.3 From b24413180f5600bcb3bb70fbed5cf186b60864bd Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 1 Nov 2017 15:07:57 +0100 Subject: License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- scripts/Makefile.build | 1 + 1 file changed, 1 insertion(+) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 061d0c3a420a..26ad24aa231c 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -1,3 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0 # ========================================================================== # Building # ========================================================================== -- cgit v1.2.3 From 5cb0512c02ecd7e6214e912e4c150f4219ac78e0 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Thu, 2 Nov 2017 14:10:37 -0700 Subject: Kbuild: don't pass "-C" to preprocessor when processing linker scripts For some odd historical reason, we preprocessed the linker scripts with "-C", which keeps comments around. That makes no sense, since the comments are not meaningful for the build anyway. And it actually breaks things, since linker scripts can't have C++ style "//" comments in them, so keeping comments after preprocessing now limits us in odd and surprising ways in our header files for no good reason. The -C option goes back to pre-git and pre-bitkeeper times, but seems to have been historically used (along with "-traditional") for some odd-ball architectures (ia64, MIPS and SH). It probably didn't matter back then either, but might possibly have been used to minimize the difference between the original file and the pre-processed result. The reason for this may be lost in time, but let's not perpetuate it only because we can't remember why we did this crazy thing. This was triggered by the recent addition of SPDX lines to the source tree, where people apparently were confused about why header files couldn't use the C++ comment format. Cc: Thomas Gleixner Cc: Greg KH Signed-off-by: Linus Torvalds --- scripts/Makefile.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 26ad24aa231c..bb831d49bcfd 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -420,7 +420,7 @@ targets += $(extra-y) $(MAKECMDGOALS) $(always) # Linker scripts preprocessor (.lds.S -> .lds) # --------------------------------------------------------------------------- quiet_cmd_cpp_lds_S = LDS $@ - cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \ + cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -U$(ARCH) \ -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $< $(obj)/%.lds: $(src)/%.lds.S FORCE -- cgit v1.2.3 From 2982c953570b2bced858613d70443c2c6a90587b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 13 Nov 2017 19:29:35 +0900 Subject: kbuild: remove redundant $(wildcard ...) for cmd_files calculation I do not see any reason why $(wildcard ...) needs to be called twice for computing cmd_files. Remove the first one. Signed-off-by: Masahiro Yamada --- scripts/Makefile.build | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 061d0c3a420a..62d5314c3b71 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -583,8 +583,7 @@ FORCE: # optimization, we don't need to read them if the target does not # exist, we will rebuild anyway in that case. -targets := $(wildcard $(sort $(targets))) -cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd)) +cmd_files := $(wildcard $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd)) ifneq ($(cmd_files),) include $(cmd_files) -- cgit v1.2.3 From 591f66899784ae0afa13ff9a3eb5ce0a4358e48b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 13 Nov 2017 19:29:36 +0900 Subject: kbuild: filter-out PHONY targets from "targets" The variable "targets" contains object paths for which existing .*.cmd files should be included. scripts/Makefile.build automatically adds $(MAKECMDGOALS) to "targets" as follows: targets += $(extra-y) $(MAKECMDGOALS) $(always) The $(MAKECMDGOALS) is a PHONY target in several places. PHONY targets never create .*.cmd files. Signed-off-by: Masahiro Yamada --- scripts/Makefile.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 62d5314c3b71..6f603770b08e 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -562,7 +562,7 @@ $(multi-used-m): FORCE $(call multi_depend, $(multi-used-m), .o, -objs -y -m) targets += $(multi-used-y) $(multi-used-m) - +targets := $(filter-out $(PHONY), $(targets)) # Descending # --------------------------------------------------------------------------- -- cgit v1.2.3 From 8a78756eb545a6fb8007fa154a626ca2bc208027 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 13 Nov 2017 19:29:37 +0900 Subject: kbuild: create object directories simpler and faster For the out-of-tree build, scripts/Makefile.build creates output directories, but this operation is not efficient. scripts/Makefile.lib calculates obj-dirs as follows: obj-dirs := $(dir $(multi-objs) $(obj-y)) Please notice $(sort ...) is not used here. Usually the result is as many "./" as objects here. For a lot of duplicated paths, the following command is invoked. _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d))) Then, the costly shell command is run over and over again. I see many points for optimization: [1] Use $(sort ...) to cut down duplicated paths before passing them to system call [2] Use single $(shell ...) instead of repeating it with $(foreach ...) This will reduce forking. [3] We can calculate obj-dirs more simply. Most of objects are already accumulated in $(targets). So, $(dir $(targets)) is fine and more comprehensive. I also removed ugly code in arch/x86/entry/vdso/Makefile. This is now really unnecessary. Signed-off-by: Masahiro Yamada Acked-by: Ingo Molnar Tested-by: Douglas Anderson --- scripts/Makefile.build | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 6f603770b08e..496ecd825c71 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -64,15 +64,6 @@ ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(h include scripts/Makefile.host endif -ifneq ($(KBUILD_SRC),) -# Create output directory if not already present -_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj)) - -# Create directories for object files if directory does not exist -# Needed when obj-y := dir/file.o syntax is used -_dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d))) -endif - ifndef obj $(warning kbuild: Makefile.build is included improperly) endif @@ -589,6 +580,12 @@ ifneq ($(cmd_files),) include $(cmd_files) endif +ifneq ($(KBUILD_SRC),) +# Create directories for object files if they do not exist +obj-dirs := $(sort $(obj) $(patsubst %/,%, $(dir $(targets)))) +$(shell mkdir -p $(obj-dirs)) +endif + # Declare the contents of the .PHONY variable as phony. We keep that # information in a variable se we can use it in if_changed and friends. -- cgit v1.2.3 From c4da7ed0e7d715b159b11efd10408510ffed1aa3 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 13 Nov 2017 19:29:38 +0900 Subject: kbuild: optimize object directory creation for incremental build The previous commit largely optimized the object directory creation. We can optimize it more for incremental build. There are already *.cmd files in the output directory. The existing *.cmd files have been picked up by $(wildcard ...). Obviously, directories containing them exist too, so we can skip "mkdir -p". With this, Kbuild runs almost zero "mkdir -p" in incremental building. Signed-off-by: Masahiro Yamada --- scripts/Makefile.build | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 496ecd825c71..8624924a2991 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -583,8 +583,13 @@ endif ifneq ($(KBUILD_SRC),) # Create directories for object files if they do not exist obj-dirs := $(sort $(obj) $(patsubst %/,%, $(dir $(targets)))) +# If cmd_files exist, their directories apparently exist. Skip mkdir. +exist-dirs := $(sort $(patsubst %/,%, $(dir $(cmd_files)))) +obj-dirs := $(strip $(filter-out $(exist-dirs), $(obj-dirs))) +ifneq ($(obj-dirs),) $(shell mkdir -p $(obj-dirs)) endif +endif # Declare the contents of the .PHONY variable as phony. We keep that # information in a variable se we can use it in if_changed and friends. -- cgit v1.2.3 From f7adc3124da019878186f1ebe98a13a1af041afd Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 8 Nov 2017 01:31:46 +0900 Subject: kbuild: create built-in.o automatically if parent directory wants it "obj-y += foo/" syntax requires Kbuild to visit the "foo" subdirectory and link built-in.o from that directory. This means foo/Makefile is responsible for creating built-in.o even if there is no object to link (in this case, built-in.o is an empty archive). We have had several fixups like commit 4b024242e8a4 ("kbuild: Fix linking error built-in.o no such file or directory"), then ended up with a complex condition as follows: ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),) builtin-target := $(obj)/built-in.o endif We still have more cases not covered by the above, so we need to add obj- := dummy.o in several places just for creating empty built-in.o. A key point is, the parent Makefile knows whether built-in.o is needed or not. If a subdirectory needs to create built-in.o, its parent can tell the fact when descending. If non-empty $(need-builtin) flag is passed from the parent, built-in.o should be created. $(obj-y) should be still checked to support the single target "%/". All of ugly tricks will go away. Signed-off-by: Masahiro Yamada Reviewed-by: Sam Ravnborg --- scripts/Makefile.build | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index f171225383cc..fc7f312bc0a7 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -76,7 +76,7 @@ lib-target := $(obj)/lib.a obj-y += $(obj)/lib-ksyms.o endif -ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),) +ifneq ($(strip $(obj-y) $(need-builtin)),) builtin-target := $(obj)/built-in.o endif @@ -561,7 +561,7 @@ targets := $(filter-out $(PHONY), $(targets)) PHONY += $(subdir-ym) $(subdir-ym): - $(Q)$(MAKE) $(build)=$@ + $(Q)$(MAKE) $(build)=$@ need-builtin=$(if $(findstring $@,$(subdir-obj-y)),1) # Add FORCE to the prequisites of a target to force it to be always rebuilt. # --------------------------------------------------------------------------- -- cgit v1.2.3 From 3a025e1d1c2ea42fa497c9c6b21c284e0f69e28b Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Mon, 20 Nov 2017 10:40:40 -0800 Subject: Add optional check for bad kernel-doc comments Implement a '-none' output mode for kernel-doc which will only output warning messages, and suppresses the warning message about there being no kernel-doc in the file. If the build has requested additional warnings, automatically check all .c files. This patch does not check .h files. Enabling the warning by default would add about 1300 warnings, so it's default off for now. People who care can use this to check they didn't break the docs and maybe we'll get all the warnings fixed and be able to enable this check by default in the future. Signed-off-by: Matthew Wilcox Signed-off-by: Jonathan Corbet --- scripts/Makefile.build | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'scripts/Makefile.build') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 2e3a10e79ca9..aceac0ba0745 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -108,6 +108,10 @@ ifneq ($(KBUILD_CHECKSRC),0) endif endif +ifneq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),) + cmd_checkdoc = $(srctree)/scripts/kernel-doc -none $< ; +endif + # Do section mismatch analysis for each module/built-in.o ifdef CONFIG_DEBUG_SECTION_MISMATCH cmd_secanalysis = ; scripts/mod/modpost $@ @@ -289,6 +293,7 @@ define rule_cc_o_c $(call echo-cmd,checksrc) $(cmd_checksrc) \ $(call cmd_and_fixdep,cc_o_c) \ $(cmd_modversions_c) \ + $(cmd_checkdoc) \ $(call echo-cmd,objtool) $(cmd_objtool) \ $(call echo-cmd,record_mcount) $(cmd_record_mcount) endef -- cgit v1.2.3