1
Commit Graph

96 Commits

Author SHA1 Message Date
Masahiro Yamada
b1992c3772 kbuild: use $(src) instead of $(srctree)/$(src) for source directory
Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

    src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

  $(obj)     - directory in the object tree
  $(src)     - directory in the source tree  (changed by this commit)
  $(objtree) - the top of the kernel object tree
  $(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-05-10 04:34:52 +09:00
Masahiro Yamada
96a29581e7 genksyms: use getopt_long() unconditionally
getopt_long() is used by various tools in the kernel (e.g. Kconfig).

It should be fine to use it all the time.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-11-28 11:22:50 +09:00
Masahiro Yamada
a19937d829 genksyms: remove the remnant of the -s option
Commit 74d9317161 ("genksyms: remove symbol prefix support") removed
the -s (--symbol-prefix) option.

Clean up the left-over.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-11-28 11:22:50 +09:00
Masahiro Yamada
5ce2176b81 genksyms: adjust the output format to modpost
Make genksyms output symbol versions in the format modpost expects,
so the 'sed' is unneeded.

This commit makes *.symversions completely unneeded.

I will keep *.symversions in .gitignore and 'make clean' for a while.
Otherwise, 'git status' might be surprising.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-05-24 16:33:20 +09:00
Masahiro Yamada
7b4537199a kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS
include/{linux,asm-generic}/export.h defines a weak symbol, __crc_*
as a placeholder.

Genksyms writes the version CRCs into the linker script, which will be
used for filling the __crc_* symbols. The linker script format depends
on CONFIG_MODULE_REL_CRCS. If it is enabled, __crc_* holds the offset
to the reference of CRC.

It is time to get rid of this complexity.

Now that modpost parses text files (.*.cmd) to collect all the CRCs,
it can generate C code that will be linked to the vmlinux or modules.

Generate a new C file, .vmlinux.export.c, which contains the CRCs of
symbols exported by vmlinux. It is compiled and linked to vmlinux in
scripts/link-vmlinux.sh.

Put the CRCs of symbols exported by modules into the existing *.mod.c
files. No additional build step is needed for modules. As before,
*.mod.c are compiled and linked to *.ko in scripts/Makefile.modfinal.

No linker magic is used here. The new C implementation works in the
same way, whether CONFIG_RELOCATABLE is enabled or not.
CONFIG_MODULE_REL_CRCS is no longer needed.

Previously, Kbuild invoked additional $(LD) to update the CRCs in
objects, but this step is unneeded too.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-05-24 16:33:20 +09:00
Masahiro Yamada
9009b45581 .gitignore: prefix local generated files with a slash
The pattern prefixed with '/' matches files in the same directory,
but not ones in sub-directories.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Andra Paraschiv <andraprs@amazon.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-05-02 00:43:35 +09:00
Masahiro Yamada
382243f346 genksyms: fix stale comment
(shipped source) is a stale comment.

Since commit 833e622459 ("genksyms: generate lexer and parser during
build instead of shipping"), there is no source file to be shipped in
this directory.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-05-02 00:43:34 +09:00
Masahiro Yamada
13940738c2 genksyms: remove useless case DOTS
This switch statement does not list out all the cases. Since the
'default' covers all the rest, the 'DOTS' case is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-02-16 12:01:45 +09:00
Masahiro Yamada
e66e13a3c9 genksyms: remove dead code for ST_TABLE_*
No one sets lexstate to ST_TABLE_*. It is is very old code, and I do
not know what was the plan at that time. Let's remove the dead code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-02-16 12:01:45 +09:00
Masahiro Yamada
ab37d5a431 genksyms: make source_file a local variable in lexer
This is only used in yylex() in lex.l

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-02-16 12:01:44 +09:00
Marco Elver
9ab55d7f24 genksyms: Ignore module scoped _Static_assert()
The C11 _Static_assert() keyword may be used at module scope, and we
need to teach genksyms about it to not abort with an error. We currently
have a growing number of static_assert() (but also direct usage of
_Static_assert()) users at module scope:

	git grep -E '^_Static_assert\(|^static_assert\(' | grep -v '^tools' | wc -l
	135

More recently, when enabling CONFIG_MODVERSIONS with CONFIG_KCSAN, we
observe a number of warnings:

	WARNING: modpost: EXPORT symbol "<..all kcsan symbols..>" [vmlinux] [...]

When running a preprocessed source through 'genksyms -w' a number of
syntax errors point at usage of static_assert()s. In the case of
kernel/kcsan/encoding.h, new static_assert()s had been introduced which
used expressions that appear to cause genksyms to not even be able to
recover from the syntax error gracefully (as it appears was the case
previously).

Therefore, make genksyms ignore all _Static_assert() and the contained
expression. With the fix, usage of _Static_assert() no longer cause
"syntax error" all over the kernel, and the above modpost warnings for
KCSAN are gone, too.

Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Joe Perches
e29a6d633e genksyms: keywords: Use __restrict not _restrict
Use the proper form of the RESTRICT keyword.

Quote the comments properly too.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-08-18 20:16:46 +09:00
Masahiro Yamada
faabed295c kbuild: introduce hostprogs-always-y and userprogs-always-y
To 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 them
because there is no dependency.

There are two types of host programs: built as the prerequisite of
another (e.g. gen_crc32table in lib/Makefile), or always built when
Kbuild visits the Makefile (e.g. genksyms in scripts/genksyms/Makefile).

The latter is typical in Makefiles under scripts/, which contains host
programs globally used during the kernel build. To build them, you need
to 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 builds
bpfilter_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 <masahiroy@kernel.org>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
2020-08-10 01:32:59 +09:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Masahiro Yamada
5f2fb52fac kbuild: rename hostprogs-y/always to hostprogs/always-y
In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

  always       ->  always-y
  hostprogs-y  ->  hostprogs

So, 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 host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-02-04 01:53:07 +09:00
Masahiro Yamada
77564a4829 genksyms: convert to SPDX License Identifier for lex.l and parse.y
I used the C comment style (/* ... */) for the flex and bison files
as in Kconfig (scripts/kconfig/{lexer.l,parser.y})

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-09-14 11:40:13 +09:00
Masahiro Yamada
69a94abb82 export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols
Arnd Bergmann reported false-positive modpost warnings detected by his
randconfig testing of linux-next.

Actually, this happens under the combination of CONFIG_MODVERSIONS
and CONFIG_TRIM_UNUSED_KSYMS since commit 15bfc2348d ("modpost:
check for static EXPORT_SYMBOL* functions").

For example, arch/arm/config/multi_v7_defconfig + CONFIG_MODVERSIONS
+ CONFIG_TRIM_UNUSED_KSYMS produces the following false-positives:

WARNING: "__lshrdi3" [vmlinux] is a static (unknown)
WARNING: "__ashrdi3" [vmlinux] is a static (unknown)
WARNING: "__aeabi_lasr" [vmlinux] is a static (unknown)
WARNING: "__aeabi_llsr" [vmlinux] is a static (unknown)
WARNING: "ftrace_set_clr_event" [vmlinux] is a static (unknown)
WARNING: "__muldi3" [vmlinux] is a static (unknown)
WARNING: "__aeabi_ulcmp" [vmlinux] is a static (unknown)
WARNING: "__ucmpdi2" [vmlinux] is a static (unknown)
WARNING: "__aeabi_lmul" [vmlinux] is a static (unknown)
WARNING: "__bswapsi2" [vmlinux] is a static (unknown)
WARNING: "__bswapdi2" [vmlinux] is a static (unknown)
WARNING: "__ashldi3" [vmlinux] is a static (unknown)
WARNING: "__aeabi_llsl" [vmlinux] is a static (unknown)

The root cause of the problem is not in the modpost, but in the
implementation of CONFIG_TRIM_UNUSED_KSYMS.

If there is at least one untrimmed symbol in the file, genksyms is
invoked to calculate CRC of *all* the exported symbols in that file
even if some of them have been trimmed due to no caller existing.

As a result, .tmp_*.ver files contain CRC of trimmed symbols, thus
unneeded, orphan __crc* symbols are added to objects. It had been
harmless until recently.

With commit 15bfc2348d ("modpost: check for static EXPORT_SYMBOL*
functions"), it is now harmful because the bogus __crc* symbols make
modpost call sym_update_crc() to add the symbols to the hash table,
but there is no one that clears the ->is_static member.

I gave Fixes to the first commit that uncovered the issue, but the
potential problem has long existed since commit f235541699
("export.h: allow for per-symbol configurable EXPORT_SYMBOL()").

Fixes: 15bfc2348d ("modpost: check for static EXPORT_SYMBOL* functions")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Arnd Bergmann <arnd@arndb.de>
2019-09-14 11:40:13 +09:00
Masahiro Yamada
e27128db62 kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN
KBUILD_ENABLE_EXTRA_GCC_CHECKS started as a switch to add extra warning
options for GCC, but now it is a historical misnomer since we use it
also for Clang, DTC, and even kernel-doc.

Rename it to more sensible, shorter KBUILD_EXTRA_WARN.

For the backward compatibility, KBUILD_ENABLE_EXTRA_GCC_CHECKS is still
supported (but not advertised in the documentation).

I also fixed up 'make help', and updated the documentation.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
2019-09-06 23:46:52 +09:00
Masahiro Yamada
6ba7dc6616 kbuild: make bison create C file and header in a single pattern rule
We generally expect bison to create not only a C file, but also a
header, which will be included from the lexer.

Currently, Kbuild generates them in separate rules. So, for instance,
when building Kconfig, you will notice bison is invoked twice:

  HOSTCC  scripts/kconfig/conf.o
  HOSTCC  scripts/kconfig/confdata.o
  HOSTCC  scripts/kconfig/expr.o
  LEX     scripts/kconfig/lexer.lex.c
  YACC    scripts/kconfig/parser.tab.h
  HOSTCC  scripts/kconfig/lexer.lex.o
  YACC    scripts/kconfig/parser.tab.c
  HOSTCC  scripts/kconfig/parser.tab.o
  HOSTCC  scripts/kconfig/preprocess.o
  HOSTCC  scripts/kconfig/symbol.o
  HOSTLD  scripts/kconfig/conf

Make handles such cases nicely in pattern rules [1]. Merge the two
rules so that one invokcation of bison can generate both of them.

  HOSTCC  scripts/kconfig/conf.o
  HOSTCC  scripts/kconfig/confdata.o
  HOSTCC  scripts/kconfig/expr.o
  LEX     scripts/kconfig/lexer.lex.c
  YACC    scripts/kconfig/parser.tab.[ch]
  HOSTCC  scripts/kconfig/lexer.lex.o
  HOSTCC  scripts/kconfig/parser.tab.o
  HOSTCC  scripts/kconfig/preprocess.o
  HOSTCC  scripts/kconfig/symbol.o
  HOSTLD  scripts/kconfig/conf

[1] Pattern rule

GNU Make manual says:
"Pattern rules may have more than one target. Unlike normal rules,
this does not act as many different rules with the same prerequisites
and recipe. If a pattern rule has multiple targets, make knows that
the rule's recipe is responsible for making all of the targets. The
recipe is executed only once to make all the targets. When searching
for a pattern rule to match a target, the target patterns of a rule
other than the one that matches the target in need of a rule are
incidental: make worries only about giving a recipe and prerequisites
to the file presently in question. However, when this file's recipe is
run, the other targets are marked as having been updated themselves."

https://www.gnu.org/software/make/manual/html_node/Pattern-Intro.html

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-08-14 01:10:42 +09:00
Will Deacon
a222061b85 genksyms: Teach parser about 128-bit built-in types
__uint128_t crops up in a few files that export symbols to modules, so
teach genksyms about it and the other GCC built-in 128-bit integer types
so that we don't end up skipping the CRC generation for some symbols due
to the parser failing to spot them:

  | WARNING: EXPORT symbol "kernel_neon_begin" [vmlinux] version
  |          generation failed, symbol will not be versioned.
  | ld: arch/arm64/kernel/fpsimd.o: relocation R_AARCH64_ABS32 against
  |     `__crc_kernel_neon_begin' can not be used when making a shared
  |     object
  | ld: arch/arm64/kernel/fpsimd.o:(.data+0x0): dangerous relocation:
  |     unsupported relocation

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-06-24 03:43:03 +09:00
Thomas Gleixner
1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Thomas Gleixner
457c899653 treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Masahiro Yamada
9cc342f6c4 treewide: prefix header search paths with $(srctree)/
Currently, the Kbuild core manipulates header search paths in a crazy
way [1].

To fix this mess, I want all Makefiles to add explicit $(srctree)/ to
the search paths in the srctree. Some Makefiles are already written in
that way, but not all. The goal of this work is to make the notation
consistent, and finally get rid of the gross hacks.

Having whitespaces after -I does not matter since commit 48f6e3cf5b
("kbuild: do not drop -I without parameter").

[1]: https://patchwork.kernel.org/patch/9632347/

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-18 11:49:57 +09:00
Masahiro Yamada
74d9317161 genksyms: remove symbol prefix support
CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX was selected by BLACKFIN, METAG.
They were removed by commit 4ba66a9760 ("arch: remove blackfin port"),
commit bb6fb6dfcc ("metag: Remove arch/metag/"), respectively.

No more architecture enables CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX,
hence the -s (--symbol-prefix) option is unnecessary.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
2018-05-17 22:43:35 +09:00
Mauro Rossi
0da7e43261 genksyms: fix typo in parse.tab.{c,h} generation rules
'quet' is replaced by 'quiet' in scripts/genksyms/Makefile

Signed-off-by: Mauro Rossi <issor.oruam@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-05 10:24:53 +09:00
Masahiro Yamada
b23d1a241f kbuild: add %.lex.c and %.tab.[ch] to 'targets' automatically
Files generated by if_changed* must be added to 'targets' to include
*.cmd files.  Otherwise, they would be regenerated every time.

The build system automatically adds objects to 'targets' where
appropriate, such as obj-y, extra-y, etc. but does nothing for
intermediate files.  So, each Makefile needs to add them by itself.

There are some common cases where objects are generated by chained
rules.  Lexers and parsers are compiled like follows:

   %.lex.o <- %.lex.c <- %.l
   %.tab.o <- %.tab.c <- %.y

They are common patterns, so it is reasonable to take care of them
in the core Makefile instead of requiring each Makefile to do so.

At this moment, you cannot delete 'target += zconf.lex.c' in the
Kconfig Makefile because zconf.lex.c is included from zconf.tab.c
instead of being compiled separately.  It should be deleted after
Kconfig is more refactored.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Frank Rowand <frowand.list@gmail.com>
2018-04-07 19:04:02 +09:00
Masahiro Yamada
833e622459 genksyms: generate lexer and parser during build instead of shipping
Now that the kernel build supports flex and bison, remove the _shipped
files and generate them during the build instead.

There are no more shipped lexer and parser, so I ripped off the rules
in scripts/Malefile.lib that were used for REGENERATE_PARSERS.

The genksyms parser has ambiguous grammar, which would emit warnings:

 scripts/genksyms/parse.y: warning: 9 shift/reduce conflicts [-Wconflicts-sr]
 scripts/genksyms/parse.y: warning: 5 reduce/reduce conflicts [-Wconflicts-rr]

They are normally suppressed, but displayed when W=1 is given.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-04-07 19:04:02 +09:00
Masahiro Yamada
9a8dfb394c kbuild: clean up *.lex.c and *.tab.[ch] patterns from top-level Makefile
Files suffixed by .lex.c, .tab.[ch] are generated lexers, parsers,
respectively.  Clean them up globally from the top Makefile.

Some of the final host programs those lexer/parser are linked into
are necessary for building external modules, but the intermediates
are unneeded.  They can be cleaned away by 'make clean' instead of
'make mrproper'.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Frank Rowand <frowand.list@gmail.com>
2018-04-07 19:04:02 +09:00
Masahiro Yamada
5988930027 .gitignore: move *.lex.c *.tab.[ch] patterns to the top-level .gitignore
These patterns are common to host programs that require lexer and parser.
Move them to the top .gitignore.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Frank Rowand <frowand.list@gmail.com>
2018-04-07 19:04:02 +09:00
Masahiro Yamada
36c1681678 genksyms: drop *.hash.c from .gitignore
This is a left-over of commit bb3290d916 ("Remove gperf usage from
toolchain").

We do not generate a hash function any more.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-13 21:50:13 +09:00
Greg Kroah-Hartman
b24413180f 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 <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Linus Torvalds
3aea311c1b genksyms: fix gperf removal conversion
I had stupidly missed one special use of 'is_reserved_word()' when I
converted the code to avoid gperf.

I had changed that function to return the token ID directly rather than
a pointer to the token descriptor structure, but that meant that the
test for "is this a reserved word" changed from checking the return
value against NULL, to checking that it wasn't negative.

And while I had converted the main token parser over, I missed the
special case of the typeof phrase handling.  And since our dependency
chain for genksyms does not include the genksyms program itself
changing, my kernel rebuild didn't show the problem.

Fixes: bb3290d916 ("Remove gperf usage from toolchain")
Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 14:32:34 -07:00
Linus Torvalds
bb3290d916 Remove gperf usage from toolchain
It turns out that gperf-3.1 changed types in the generated code in ways
that aren't even trivially detectable without having to generate a test-file.

It's just not worth using tools and libraries from clowns that don't
understand or care about compatibility.  So get rid of gperf.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-19 11:02:53 -07:00
Nicolas Iooss
3def03441e genksyms: add printf format attribute to error_with_pos()
When compiling with -Wsuggest-attribute=format in HOSTCFLAGS, gcc
complains that error_with_pos() may be declared with a printf format
attribute:

    scripts/genksyms/genksyms.c:726:3: warning: function might be
    possible candidate for ‘gnu_printf’ format attribute
    [-Wsuggest-attribute=format]
       vfprintf(stderr, fmt, args);
       ^~~~~~~~

This would allow catching printf-format errors at compile time in
callers to error_with_pos(). Add this attribute.

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-06-06 01:22:48 +09:00
Masahiro Yamada
ef44bca87c Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull Michal's unmerged branch into the new Kbuild repository.

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  genksyms: Regenerate parser
  genksyms: Fix segfault with invalid declarations
2017-03-11 01:18:25 +09:00
Ard Biesheuvel
56067812d5 kbuild: modversions: add infrastructure for emitting relative CRCs
This add the kbuild infrastructure that will allow architectures to emit
vmlinux symbol CRCs as 32-bit offsets to another location in the kernel
where the actual value is stored. This works around problems with CRCs
being mistaken for relocatable symbols on kernels that self relocate at
runtime (i.e., powerpc with CONFIG_RELOCATABLE=y)

For the kbuild side of things, this comes down to the following:

 - introducing a Kconfig symbol MODULE_REL_CRCS

 - adding a -R switch to genksyms to instruct it to emit the CRC symbols
   as references into the .rodata section

 - making modpost distinguish such references from absolute CRC symbols
   by the section index (SHN_ABS)

 - making kallsyms disregard non-absolute symbols with a __crc_ prefix

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-03 08:28:25 -08:00
Michal Marek
fde42bfcd2 genksyms: Regenerate parser
Regenerate the parser after d920f7c662 ("genksyms: Fix segfault with
invalid declarations").

Reported-and-tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
2017-01-05 13:01:13 +01:00
Michal Marek
d920f7c662 genksyms: Fix segfault with invalid declarations
Do not try to recover too early and segfault when parsing invalid
declarations such as

echo 'int (int);' | scripts/genksyms/genksyms
echo 'int a, (int);' | scripts/genksyms/genksyms
echo 'extern void *__inline_memcpy((void *), (const void *), (__kernel_size_t));' | scripts/genksyms/genksyms

The last one was a real-life bug with
include/asm-generic/asm-prototypes.h on x86_64.

Reported-and-tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
2017-01-05 13:00:54 +01:00
Michal Marek
7e441fe759 genksyms: Regenerate parser
Regenerate the keyword table and parser after commit 0efdb22823
("kbuild/genksyms: handle va_list type").

Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-29 15:57:40 +01:00
Nicholas Piggin
0efdb22823 kbuild/genksyms: handle va_list type
genksyms currently does not handle va_list. Add the __builtin_va_list
keyword as a type. This reduces the amount of syntax errors thrown,
but so far no export symbol has a type with a va_list argument, so
there is currently no bug in the end result.

Note: this patch does not regenerate shipped parser files.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-29 15:53:19 +01:00
Michal Marek
5c6f3225d0 kbuild: Regenerate genksyms lexer
Update the lexer after 4fab91605a ("kbuild: genksyms fix for typeof
handling").

Signed-off-by: Michal Marek <mmarek@suse.com>
2016-08-25 20:03:51 +02:00
Nicholas Piggin
4fab91605a kbuild: genksyms fix for typeof handling
The tokenizer misses counting an open-parenthesis when parsing a
non-trivial typeof beginning with an open-parenthesis. This function
in include/linux/ceph/libceph.h

static type *lookup_##name(struct rb_root *root,
                           typeof(((type *)0)->keyfld) key)

When instantiated in net/ceph/mon_client.c, causes subsequent symbols
including an EXPORT_SYMBOL in that file to be lost.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-08-25 18:55:37 +02:00
Maxim Zhukov
4deaaa4deb scripts: genksyms: fix resource leak
This commit fixed resource leak at func main

Signed-off-by: Maxim Zhukov <mussitantesmortem@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 09:24:49 +02:00
Michal Marek
a78f70e8d6 genksyms: Handle string literals with spaces in reference files
The reference files use spaces to separate tokens, however, we must
preserve spaces inside string literals. Currently the only case in the
tree is struct edac_raw_error_desc in <linux/edac.h>:

$ KBUILD_SYMTYPES=1 make -s drivers/edac/amd64_edac.symtypes
$ mv drivers/edac/amd64_edac.{symtypes,symref}
$ KBUILD_SYMTYPES=1 make -s drivers/edac/amd64_edac.symtypes
drivers/edac/amd64_edac.c:527: warning: amd64_get_dram_hole_info: modversion changed because of changes in struct edac_raw_error_desc

Signed-off-by: Michal Marek <mmarek@suse.com>
2015-12-09 15:19:23 +01:00
Michal Marek
5b733faca6 genksyms: Regenerate parser
Rebuild the parser after commit 1c722503fa (genksyms: Duplicate
function pointer type definitions segfault), using bison 2.7.

Signed-off-by: Michal Marek <mmarek@suse.com>
2015-08-20 14:57:47 +02:00
Richard Yao
1c722503fa genksyms: Duplicate function pointer type definitions segfault
I noticed that genksyms will segfault when it sees duplicate function
pointer type declaration when I placed the same function pointer
definition in two separate headers in a local branch as an intermediate
step of some refactoring. This can be reproduced by piping the following
minimal test case into `genksyms -r /dev/null` or alternatively, putting
it into a C file attempting a build:

typedef int (*f)();
typedef int (*f)();

Attaching gdb to genksyms to understand this failure is useless without
changing CFLAGS to emit debuginfo. Once you have debuginfo, you will
find that the failure is that `char *s` was NULL and the program
executed `while(*s)`. At which point, further debugging requires
familiarity with compiler front end / parser development.

What happens is that flex identifies the first instance of the token "f"
as IDENT and the yacc parser adds it to the symbol table. On the second
instance, flex will identify "f" as TYPE, which triggers an error case
in the yacc parser. Given that TYPE would have been IDENT had it not
been in the symbol table, the the segmentaion fault could be avoided by
treating TYPE as IDENT in the affected rule.

Some might consider placing identical function pointer type declarations
in different headers to be poor style might consider a failure to be
beneficial. However, failing through a segmentation fault makes the
cause non-obvious and can waste the time of anyone who encounters it.

Signed-off-by: Richard Yao <richard.yao@clusterhq.com>
Acked-by: Madhuri Yechuri <madhuriyechuri@clusterhq.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2015-08-20 14:55:55 +02:00
Jan Beulich
dc53324060 genksyms: fix typeof() handling
Recent increased use of typeof() throughout the tree resulted in a
number of symbols (25 in a typical distro config of ours) not getting a
proper CRC calculated for them anymore, due to the parser in genksyms
not coping with several of these uses (interestingly in the majority of
[if not all] cases the problem is due to the use of typeof() in code
preceding a certain export, not in the declaration/definition of the
exported function/object itself; I wasn't able to find a way to address
this more general parser shortcoming).

The use of parameter_declaration is a little more relaxed than would be
ideal (permitting not just a bare type specification, but also one with
identifier), but since the same code is being passed through an actual
compiler, there's no apparent risk of allowing through any broken code.

Otoh using parameter_declaration instead of the ad hoc
"decl_specifier_seq '*'" / "decl_specifier_seq" pair allows all types to
be handled rather than just plain ones and pointers to plain ones.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:20:52 -07:00
James Hogan
d70f82acf3 genksyms: pass symbol-prefix instead of arch
Pass symbol-prefix to genksyms instead of arch, so that the decision
what symbol prefix to use is kept in one place.

Basically genksyms used to take a -a $ARCH argument and it used that to
determine whether to add an underscore symbol prefix. It's now changed
to take a -s $SYMBOL_PREFIX argument so that the caller decides whether
a symbol prefix is required. The build system then uses
CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX to determine whether to pass the
argument.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-20 11:27:27 +10:30
James Hogan
97c3ec6308 genksyms: fix metag symbol prefix on crc symbols
Meta uses symbol prefixes, so add "metag" to the list of architectures
to set the mod_prefix to "_" for. This fixes __crc_* symbols to add the
extra underscore to match _CRC_SYMBOL macro in <linux/export.h> and so
that modpost finds them.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
2013-03-02 20:11:13 +00:00
Fernando Luis Vázquez Cao
603d8c0adb scripts/genksyms: clean lex/yacc generated files
Add "keywords.hash.c", "lex.lex.c", "parse.tab.c" and "parse.tab.h" to
clean-list so that they get automagically deleted at clean/mrproper
time.

Signed-off-by: Fernando Luis Vazquez Cao<fernando@oss.ntt.co.jp>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-01-08 14:48:15 +01:00