Commit Graph

11 Commits

Author SHA1 Message Date
Masahiro Yamada 2047ace966 kbuild: use always-y instead of extra-y
As commit d0e628cd81 ("kbuild: doc: clarify the difference between
extra-y and always-y") explained, extra-y should be used for listing
the prerequisites of vmlinux.

These targets are not related to vmlinux. always-y is a better fix.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
2021-02-16 12:01:45 +09:00
Masahiro Yamada 051f278e9d kbuild: replace KBUILD_SRCTREE with boolean building_out_of_srctree
Commit 25b146c5b8 ("kbuild: allow Kbuild to start from any directory")
deprecated KBUILD_SRCTREE.

It is only used in tools/testing/selftest/ to distinguish out-of-tree
build. Replace it with a new boolean flag, building_out_of_srctree.

I also replaced the conditional ($(srctree),.) because the next commit
will allow an absolute path to be used for $(srctree) even when building
in the source tree.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-07-11 00:05:09 +09:00
Masahiro Yamada a9a49c2ad9 kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build
KBUILD_SRC was conventionally used for some different purposes:
 [1] To remember the source tree path
 [2] As a flag to check if sub-make is already done
 [3] As a flag to check if Kbuild runs out of tree

For [1], we do not need to remember it because the top Makefile
can compute it by $(realpath $(dir $(lastword $(MAKEFILE_LIST))))

[2] has been replaced with self-commenting 'sub_make_done'.

For [3], we can distinguish in-tree/out-of-tree by comparing
$(srctree) and '.'

This commit converts [3] to prepare for the KBUILD_SRC removal.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-02 23:28:04 +09:00
Masahiro Yamada b513adf45c scripts/gdb: refactor rules for symlink creation
gdb-scripts is not a real object, but (ab)used like a phony target.

Rewrite the code in a more Kbuild-ish way. Add symlinks to extra-y
and use if_changed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-02-27 21:41:04 +09:00
Masahiro Yamada 1e5ff84ffe scripts/gdb: do not descend into scripts/gdb from scripts
Currently, Kbuild descends from scripts/Makefile to scripts/gdb/Makefile
just for creating symbolic links, but it does not need to do it so early.

Merge the two descending paths to simplify the code.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-02-27 21:40:09 +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
Masahiro Yamada 8e9b466799 kbuild: use $(abspath ...) instead of $(shell cd ... && /bin/pwd)
Kbuild conventionally uses $(shell cd ... && /bin/pwd) idiom to get
the absolute path of the directory because GNU Make 3.80, the minimal
supported version at that time, did not support $(abspath ...) or
$(realpath ...).

Commit 37d69ee308 ("docs: bump minimal GNU Make version to 3.81")
dropped the GNU Make 3.80 support, so we are now allowed to use those
make-builtin helpers.

This conversion will provide better portability without relying on
the pwd command or its location /bin/pwd.

I am intentionally using $(realpath ...) instead $(abspath ...) in
some places.  The difference between the two is $(realpath ...)
returns an empty string if the given path does not exist.  It is
convenient in places where we need to error-out if the makefile fails
to create an output directory.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Thierry Reding <treding@nvidia.com>
2017-09-01 08:50:32 +09:00
Kieran Bingham 834a35296a scripts/gdb: rebuild constants.py on dependancy change
The autogenerated constants.py file was only being built on the initial
call, and if the constants.py.in file changed.  As we are utilising the
CPP hooks, we can successfully use the call if_changed_dep rules to
determine when to rebuild the file based on it's inclusions.

Link: http://lkml.kernel.org/r/1467127337-11135-3-git-send-email-kieran@bingham.xyz
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-15 14:54:27 +09:00
Kieran Bingham abb035b482 scripts/gdb: silence 'nothing to do' message
The constants.py generation, involves a rule to link into the main
makefile.  This rule has no command and generates a spurious warning
message in the build logs when CONFIG_SCRIPTS_GDB is enabled.

Fix simply by giving a no-op action

Link: http://lkml.kernel.org/r/1467127337-11135-2-git-send-email-kieran@bingham.xyz
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-15 14:54:27 +09:00
Kieran Bingham f197d75fca scripts/gdb: provide linux constants
Some macro's and defines are needed when parsing memory, and without
compiling the kernel as -g3 they are not available in the debug-symbols.

We use the pre-processor here to extract constants to a dedicated module
for the linux debugger extensions

Top level Kbuild is used to call in and generate the constants file,
while maintaining dependencies on autogenerated files in
include/generated

Link: http://lkml.kernel.org/r/bc3df9c25f57ea72177c066a51a446fc19e2c27f.1462865983.git.jan.kiszka@siemens.com
Signed-off-by: Kieran Bingham <kieran.bingham@linaro.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.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>
2016-05-23 17:04:14 -07:00
Jan Kiszka 3ee7b3fa2c scripts/gdb: add infrastructure
This provides the basic infrastructure to load kernel-specific python
helper scripts when debugging the kernel in gdb.

The loading mechanism is based on gdb loading for <objfile>-gdb.py when
opening <objfile>.  Therefore, this places a corresponding link to the
main helper script into the output directory that contains vmlinux.

The main scripts will pull in submodules containing Linux specific gdb
commands and functions.  To avoid polluting the source directory with
compiled python modules, we link to them from the object directory.

Due to gdb.parse_and_eval and string redirection for gdb.execute, we
depend on gdb >= 7.2.

This feature is enabled via CONFIG_GDB_SCRIPTS.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Michal Marek <mmarek@suse.cz>		[kbuild stuff]
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-17 14:34:53 -08:00