Changes in Makefile

7f7f6f7a - Makefile: remove redundant tool coverage variables

Mon, 06 May 2024 13:35:43 +0000

Makefile: remove redundant tool coverage variablesNow Kbuild provides reasonable defaults for objtool, sanitizers, andprofilers.Remove redundant variables.Note:This commit changes the coverage for some objects: - include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV - include arch/sparc/vdso/vdso-image-*.o into UBSAN - include arch/sparc/vdso/vma.o into UBSAN - include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vma.o into GCOV, KCOV - include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOVI believe these are positive effects because all of them are kernelspace objects.Signed-off-by: Masahiro Yamada Reviewed-by: Kees Cook Tested-by: Roberto Sassu List of files: /linux-6.15/scripts/mod/Makefile

40745327 - modpost: Optimize symbol search from linear to binary search

Tue, 26 Sep 2023 12:40:44 +0000

modpost: Optimize symbol search from linear to binary searchModify modpost to use binary search for converting addresses backinto symbol references. Previously it used linear search.This change saves a few seconds of wall time for defconfig builds,but can save several minutes on allyesconfigs.Before:$ make LLVM=1 -j128 allyesconfig vmlinux -s KCFLAGS="-Wno-error"$ time scripts/mod/modpost -M -m -a -N -o vmlinux.symvers vmlinux.o198.38user 1.27system 3:19.71elapsedAfter:$ make LLVM=1 -j128 allyesconfig vmlinux -s KCFLAGS="-Wno-error"$ time scripts/mod/modpost -M -m -a -N -o vmlinux.symvers vmlinux.o11.91user 0.85system 0:12.78elapsedSigned-off-by: Jack Brennen Tested-by: Nick Desaulniers Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/mod/Makefile

d23dddf8 - scripts/mod: disable LTO for empty.c

Fri, 11 Dec 2020 18:46:28 +0000

scripts/mod: disable LTO for empty.cWith CONFIG_LTO_CLANG, clang generates LLVM IR instead of ELF objectfiles. As empty.o is used for probing target properties, disable LTOfor it to produce an object file instead.Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20201211184633.3213045-12-samitolvanen@google.com List of files: /linux-6.15/scripts/mod/Makefile

faabed29 - kbuild: introduce hostprogs-always-y and userprogs-always-y

Sat, 01 Aug 2020 12:27:18 +0000

kbuild: introduce hostprogs-always-y and userprogs-always-yTo build host programs, you need to add the program names to 'hostprogs'to use the necessary build rule, but it is not enough to build thembecause there is no dependency.There are two types of host programs: built as the prerequisite ofanother (e.g. gen_crc32table in lib/Makefile), or always built whenKbuild visits the Makefile (e.g. genksyms in scripts/genksyms/Makefile).The latter is typical in Makefiles under scripts/, which contains hostprograms globally used during the kernel build. To build them, you needto add them to both 'hostprogs' and 'always-y'.This commit adds hostprogs-always-y as a shorthand.The same applies to user programs. net/bpfilter/Makefile buildsbpfilter_umh on demand, hence always-y is unneeded. In contrast,programs under samples/ are added to both 'userprogs' and 'always-y'so they are always built when Kbuild visits the Makefiles.userprogs-always-y works as a shorthand.Signed-off-by: Masahiro Yamada Acked-by: Miguel Ojeda List of files: /linux-6.15/scripts/mod/Makefile

5f2fb52f - kbuild: rename hostprogs-y/always to hostprogs/always-y

Sat, 01 Feb 2020 16:49:24 +0000

kbuild: rename hostprogs-y/always to hostprogs/always-yIn old days, the "host-progs" syntax was used for specifying hostprograms. It was renamed to the current "hostprogs-y" in 2004.It is typically useful in scripts/Makefile because it allows Kbuild toselectively compile host programs based on the kernel configuration.This commit renames like follows: always -> always-y hostprogs-y -> hostprogsSo, scripts/Makefile will look like this: always-$(CONFIG_BUILD_BIN2C) += ... always-$(CONFIG_KALLSYMS) += ... ... hostprogs := $(always-y) $(always-m)I think this makes more sense because a host program is always a hostprogram, irrespective of the kernel configuration. We want to specifywhich ones to compile by CONFIG options, so always-y will be handier.The "always", "hostprogs-y", "hostprogs-m" will be kept for backwardcompatibility for a while.Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/mod/Makefile

6ac38934 - Revert "kbuild/Makefile: Prepare for using macros in inline assembly code to work around asm() related GCC inlining bugs"

Wed, 19 Dec 2018 10:27:05 +0000

Revert "kbuild/Makefile: Prepare for using macros in inline assembly code to work around asm() related GCC inlining bugs"This reverts commit 77b0bf55bc675233d22cd5df97605d516d64525e.See this commit for details about the revert: e769742d3584 ("Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"") Conflicts: arch/x86/MakefileReported-by: Masahiro Yamada Reviewed-by: Borislav Petkov Reviewed-by: Thomas Gleixner Cc: Juergen Gross Cc: Richard Biener Cc: Kees Cook Cc: Segher Boessenkool Cc: Ard Biesheuvel Cc: Peter Zijlstra Cc: Josh Poimboeuf Cc: Nadav Amit Cc: Linus Torvalds Cc: linux-kernel@vger.kernel.orgSigned-off-by: Ingo Molnar List of files: /linux-6.15/scripts/mod/Makefile

60df1aee - kbuild: move modpost out of 'scripts' target

Thu, 29 Nov 2018 03:13:24 +0000

kbuild: move modpost out of 'scripts' targetI am eagar to build under the scripts/ directory only with $(HOSTCC),but scripts/mod/ highly depends on the $(CC) and target arch headers.That it why the 'scripts' target must depend on 'asm-generic','gcc-plugins', and $(autoksyms_h).Move it to the 'prepare0' stage. I know this is a cheesy workaround,but better than the current situation.Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/mod/Makefile

77b0bf55 - kbuild/Makefile: Prepare for using macros in inline assembly code to work around asm() related GCC inlining bugs

Wed, 03 Oct 2018 21:30:52 +0000

kbuild/Makefile: Prepare for using macros in inline assembly code to work around asm() related GCC inlining bugsUsing macros in inline assembly allows us to work around bugsin GCC's inlining decisions.Compile macros.S and use it to assemble all C files.Currently only x86 will use it.Background:The inlining pass of GCC doesn't include an assembler, so it's not awareof basic properties of the generated code, such as its size in bytes,or that there are such things as discontiuous blocks of code and datadue to the newfangled linker feature called 'sections' ...Instead GCC uses a lazy and fragile heuristic: it does a linear count ofcertain syntactic and whitespace elements in inlined assembly block sourcecode, such as a count of new-lines and semicolons (!), as a poor substitutefor "code size and complexity".Unsurprisingly this heuristic falls over and breaks its neck whith certaincommon types of kernel code that use inline assembly, such as the frequentpractice of putting useful information into alternative sections.As a result of this fresh, 20+ years old GCC bug, GCC's inlining decisionsare effectively disabled for inlined functions that make use of such asm()blocks, because GCC thinks those sections of code are "large" - when inreality they are often result in just a very low number of machineinstructions.This absolute lack of inlining provess when GCC comes across such asm()blocks both increases generated kernel code size and causes performanceoverhead, which is particularly noticeable on paravirt kernels, which makefrequent use of these inlining facilities in attempt to stay out of theway when running on baremetal hardware.Instead of fixing the compiler we use a workaround: we set an assembly macroand call it from the inlined assembly block. As a result GCC considers theinline assembly block as a single instruction. (Which it often isn't but I digress.)This uglifies and bloats the source code - for example just the refcountrelated changes have this impact: Makefile | 9 +++++++-- arch/x86/Makefile | 7 +++++++ arch/x86/kernel/macros.S | 7 +++++++ scripts/Kbuild.include | 4 +++- scripts/mod/Makefile | 2 ++ 5 files changed, 26 insertions(+), 3 deletions(-)Yay readability and maintainability, it's not like assembly code is hard to readand maintain ...We also hope that GCC will eventually get fixed, but we are not holdingour breath for that. Yet we are optimistic, it might still happen, any decade now.[ mingo: Wrote new changelog describing the background. ]Tested-by: Kees Cook Signed-off-by: Nadav Amit Acked-by: Masahiro Yamada Acked-by: Peter Zijlstra (Intel) Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Michal Marek Cc: Peter Zijlstra Cc: Sam Ravnborg Cc: Thomas Gleixner Cc: linux-kbuild@vger.kernel.orgLink: http://lkml.kernel.org/r/20181003213100.189959-3-namit@vmware.comSigned-off-by: Ingo Molnar List of files: /linux-6.15/scripts/mod/Makefile

b2441318 - License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Wed, 01 Nov 2017 14:07:57 +0000

License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseMany source files in the tree are missing licensing information, whichmakes it harder for compliance tools to determine the correct license.By default all files without license information are under the defaultlicense 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 bindingshorthand, which can be used instead of the full boiler plate text.This patch is based on work done by Thomas Gleixner and Kate Stewart andPhilippe Ombredanne.How this work was done:Patches were generated and checked against linux-4.14-rc6 for a subset ofthe 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 caseswhere non-standard license headers were used, and references to licensehad to be inferred by heuristics based on keywords.The analysis to determine which SPDX License Identifier to be applied toa file was done in a spreadsheet of side by side results from of theoutput of two independent scanners (ScanCode & Windriver) producing SPDXtag:value files created by Philippe Ombredanne. Philippe prepared thebase 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 filesassessed. Kate Stewart did a file by file comparison of the scannerresults in the spreadsheet to determine which SPDX license identifier(s)to be applied to the file. She confirmed any determination that was notimmediately 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 licenseidentifiers 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 thespreadsheet to determine the SPDX license identifiers to apply to thesource files by Kate, Philippe, Thomas and, in some cases, confirmationby lawyers working with the Linux Foundation.Kate also obtained a third independent scan of the 4.13 code base fromFOSSology, and compared selected files where the other two scannersdisagreed against that SPDX file, to see if there was new insights. TheWindriver scanner is based on an older version of FOSSology in part, sothey are related.Thomas did random spot checks in about 500 files from the spreadsheetsfor the uapi headers and agreed with SPDX license identifier in thefiles he inspected. For the non-uapi files Thomas did random spot checksin about 15000 files.In initial set of patches against 4.14-rc6, 3 files were found to havecopy/paste license identifier errors, and have been fixed to reflect thecorrect identifier.Additionally Philippe spent 10 hours this week doing a detailed manualinspection and review of the 12,461 patched files from the initial patchversion 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 correctThis produced a worksheet with 20 files needing minor correction. Thisworksheet was then exported into 3 different .csv files for thedifferent types of files to be modified.These .csv files were then reviewed by Greg. Thomas wrote a script toparse the csv files and add the proper SPDX tag to the file, in theformat that the file expected. This script was further refined by Gregbased on the output to detect more types of files automatically and todistinguish between header and source .c files (which need differentcomment types.) Finally Greg ran the script using the .csv files togenerate the patches.Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman List of files: /linux-6.15/scripts/mod/Makefile

ebf003f0 - kbuild: Consolidate header generation from ASM offset information

Wed, 12 Apr 2017 19:43:52 +0000

kbuild: Consolidate header generation from ASM offset informationLargely redundant code is used in different places to generate C headersfrom offset information extracted from assembly language output.Consolidate the code in Makefile.lib and use this instead.Signed-off-by: Matthias Kaehlcke Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/mod/Makefile

c0dd6716 - objtool: Mark non-standard object files and directories

Mon, 29 Feb 2016 04:22:34 +0000

objtool: Mark non-standard object files and directoriesCode which runs outside the kernel's normal mode of operation often doesunusual things which can cause a static analysis tool like objtool toemit false positive warnings: - boot image - vdso image - relocation - realmode - efi - head - purgatory - modpostSet OBJECT_FILES_NON_STANDARD for their related files and directories,which will tell objtool to skip checking them. It's ok to skip thembecause they don't affect runtime stack traces.Also skip the following code which does the right thing with respect toframe pointers, but is too "special" to be validated by a tool: - entry - mcountAlso skip the test_nx module because it modifies its exception handlingtable at runtime, which objtool can't understand. Fortunately it'sjust a test module so it doesn't matter much.Currently objtool is the only user of OBJECT_FILES_NON_STANDARD, but itmight eventually be useful for other tools.Signed-off-by: Josh Poimboeuf Cc: Andrew Morton Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Chris J Arges Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.orgLink: http://lkml.kernel.org/r/366c080e3844e8a5b6a0327dc7e8c2b90ca3baeb.1456719558.git.jpoimboe@redhat.comSigned-off-by: Ingo Molnar List of files: /linux-6.15/scripts/mod/Makefile

bd701343 - improve modalias building

Wed, 29 May 2013 12:18:56 +0000

improve modalias buildingFor one, there's no point in the respective pieces to be rebuiltunconditionally on each and every rebuild.Second there's no need to invent a custom rule for generating the .sfile from the .c source - we can simply use the generic rule here.And finally, $(obj) should be used to refer to files in the build tree(rather than spelling out the subdirectory).Signed-off-by: Jan Beulich Signed-off-by: Michal Marek List of files: /linux-6.15/scripts/mod/Makefile

f82935eb - scripts/mod: Spelling s/DEVICEVTABLE/DEVICETABLE/

Fri, 17 May 2013 12:18:35 +0000

scripts/mod: Spelling s/DEVICEVTABLE/DEVICETABLE/Signed-off-by: Geert Uytterhoeven Signed-off-by: Michal Marek List of files: /linux-6.15/scripts/mod/Makefile

22fc4273 - Fix cleaning in scripts/mod

Sat, 04 May 2013 14:32:53 +0000

Fix cleaning in scripts/modMake sure devicetable-offsets.h is cleaned in the scripts/mod directorySigned-off-by: Andreas Schwab Tested-by: Geert Uytterhoeven Signed-off-by: Michal Marek List of files: /linux-6.15/scripts/mod/Makefile

6543becf - mod/file2alias: make modalias generation safe for cross compiling

Sun, 20 Jan 2013 16:58:47 +0000

mod/file2alias: make modalias generation safe for cross compilingUse the target compiler to compute the offsets for the fields of thedevice_id structures, so that it won't be broken by different alignmentsbetween the host and target ABIs.This also fixes missing endian corrections for some modaliases.Signed-off-by: Andreas Schwab Signed-off-by: Michal Marek List of files: /linux-6.15/scripts/mod/Makefile

9e1b9b80 - module: make MODULE_SYMBOL_PREFIX into a CONFIG option

Sat, 07 Nov 2009 21:03:54 +0000

module: make MODULE_SYMBOL_PREFIX into a CONFIG optionThe next commit will require the use of MODULE_SYMBOL_PREFIX in.tmp_exports-asm.S. Currently it is mixed in with C structuredefinitions in "asm/module.h". Move the definition of this arch optioninto Kconfig, so it can be easily accessed by any code.This also lets modpost.c use the same definition. Previously modpostrelied on a hardcoded list of architectures in mk_elfconfig.c.A build test for blackfin, one of the two MODULE_SYMBOL_PREFIX archs,showed the generated code was unchanged. vmlinux was identical savefor build ids, and an apparently randomized suffix on a single "__key"symbol in the kallsyms data).Signed-off-by: Alan Jenkins Acked-by: Mike Frysinger (blackfin)CC: Sam Ravnborg Signed-off-by: Rusty Russell List of files: /linux-6.15/scripts/mod/Makefile

1da177e4 - Linux-2.6.12-rc2

Sat, 16 Apr 2005 22:20:36 +0000

Linux-2.6.12-rc2Initial git repository build. I'm not bothering with the full history,even though we have it. We can create a separate "historical" gitarchive of that later if we want to, and in the meantime it's about3.2GB when imported into git - space that would just make the earlygit days unnecessarily complicated, when we don't have a lot of goodinfrastructure for it.Let it rip! List of files: /linux-6.15/scripts/mod/Makefile