2012-05-05 15:18:41 +07:00
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#!/bin/sh
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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>
2017-11-01 21:07:57 +07:00
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# SPDX-License-Identifier: GPL-2.0
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2012-05-05 15:18:41 +07:00
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#
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# link vmlinux
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#
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# vmlinux is linked from the objects selected by $(KBUILD_VMLINUX_INIT) and
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2018-02-10 21:25:04 +07:00
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# $(KBUILD_VMLINUX_MAIN) and $(KBUILD_VMLINUX_LIBS). Most are built-in.a files
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2017-06-19 22:52:05 +07:00
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# from top-level directories in the kernel tree, others are specified in
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# arch/$(ARCH)/Makefile. Ordering when linking is important, and
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# $(KBUILD_VMLINUX_INIT) must be first. $(KBUILD_VMLINUX_LIBS) are archives
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# which are linked conditionally (not within --whole-archive), and do not
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# require symbol indexes added.
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2012-05-05 15:18:41 +07:00
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#
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# vmlinux
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# ^
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# |
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# +-< $(KBUILD_VMLINUX_INIT)
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# | +--< init/version.o + more
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# |
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# +--< $(KBUILD_VMLINUX_MAIN)
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2018-02-10 21:25:04 +07:00
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# | +--< drivers/built-in.a mm/built-in.a + more
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2012-05-05 15:18:41 +07:00
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# |
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2017-06-19 22:52:05 +07:00
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# +--< $(KBUILD_VMLINUX_LIBS)
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# | +--< lib/lib.a + more
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# |
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2012-05-05 15:18:41 +07:00
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# +-< ${kallsymso} (see description in KALLSYMS section)
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#
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# vmlinux version (uname -v) cannot be updated during normal
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# descending-into-subdirs phase since we do not yet know if we need to
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# update vmlinux.
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# Therefore this step is delayed until just before final link of vmlinux.
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#
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# System.map is generated to document addresses of all kernel symbols
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# Error out on error
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set -e
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# Nice output in kbuild format
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# Will be supressed by "make -s"
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info()
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{
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if [ "${quiet}" != "silent_" ]; then
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printf " %-7s %s\n" ${1} ${2}
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fi
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}
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# Link of vmlinux.o used for section mismatch analysis
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# ${1} output file
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modpost_link()
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{
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kbuild: allow architectures to use thin archives instead of ld -r
ld -r is an incremental link used to create built-in.o files in build
subdirectories. It produces relocatable object files containing all
its input files, and these are are then pulled together and relocated
in the final link. Aside from the bloat, this constrains the final
link relocations, which has bitten large powerpc builds with
unresolvable relocations in the final link.
Alan Modra has recommended the kernel use thin archives for linking.
This is an alternative and means that the linker has more information
available to it when it links the kernel.
This patch enables a config option architectures can select, which
causes all built-in.o files to be built as thin archives. built-in.o
files in subdirectories do not get symbol table or index attached,
which improves speed and size. The final link pass creates a
built-in.o archive in the root output directory which includes the
symbol table and index. The linker then uses takes this file to link.
The --whole-archive linker option is required, because the linker now
has visibility to every individual object file, and it will otherwise
just completely avoid including those without external references
(consider a file with EXPORT_SYMBOL or initcall or hardware exceptions
as its only entry points). The traditional built works "by luck" as
built-in.o files are large enough that they're going to get external
references. However this optimisation is unpredictable for the kernel
(due to above external references), ineffective at culling unused, and
costly because the .o files have to be searched for references.
Superior alternatives for link-time culling should be used instead.
Build characteristics for inclink vs thinarc, on a small powerpc64le
pseries VM with a modest .config:
inclink thinarc
sizes
vmlinux 15 618 680 15 625 028
sum of all built-in.o 56 091 808 1 054 334
sum excluding root built-in.o 151 430
find -name built-in.o | xargs rm ; time make vmlinux
real 22.772s 21.143s
user 13.280s 13.430s
sys 4.310s 2.750s
- Final kernel pulled in only about 6K more, which shows how
ineffective the object file culling is.
- Build performance looks improved due to less pagecache activity.
On IO constrained systems it could be a bigger win.
- Build size saving is significant.
Side note, the toochain understands archives, so there's some tricks,
$ ar t built-in.o # list all files you linked with
$ size built-in.o # and their sizes
$ objdump -d built-in.o # disassembly (unrelocated) with filenames
Implementation by sfr, minor tweaks by npiggin.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-08-24 19:29:19 +07:00
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local objects
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2018-02-10 21:25:03 +07:00
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objects="--whole-archive \
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2019-01-17 07:10:03 +07:00
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${KBUILD_VMLINUX_INIT} \
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${KBUILD_VMLINUX_MAIN} \
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2018-02-10 21:25:03 +07:00
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--no-whole-archive \
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--start-group \
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${KBUILD_VMLINUX_LIBS} \
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--end-group"
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2018-08-24 06:20:39 +07:00
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${LD} ${KBUILD_LDFLAGS} -r -o ${1} ${objects}
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2012-05-05 15:18:41 +07:00
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}
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# Link of vmlinux
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# ${1} - optional extra .o files
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# ${2} - output file
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vmlinux_link()
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{
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local lds="${objtree}/${KBUILD_LDS}"
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kbuild: allow architectures to use thin archives instead of ld -r
ld -r is an incremental link used to create built-in.o files in build
subdirectories. It produces relocatable object files containing all
its input files, and these are are then pulled together and relocated
in the final link. Aside from the bloat, this constrains the final
link relocations, which has bitten large powerpc builds with
unresolvable relocations in the final link.
Alan Modra has recommended the kernel use thin archives for linking.
This is an alternative and means that the linker has more information
available to it when it links the kernel.
This patch enables a config option architectures can select, which
causes all built-in.o files to be built as thin archives. built-in.o
files in subdirectories do not get symbol table or index attached,
which improves speed and size. The final link pass creates a
built-in.o archive in the root output directory which includes the
symbol table and index. The linker then uses takes this file to link.
The --whole-archive linker option is required, because the linker now
has visibility to every individual object file, and it will otherwise
just completely avoid including those without external references
(consider a file with EXPORT_SYMBOL or initcall or hardware exceptions
as its only entry points). The traditional built works "by luck" as
built-in.o files are large enough that they're going to get external
references. However this optimisation is unpredictable for the kernel
(due to above external references), ineffective at culling unused, and
costly because the .o files have to be searched for references.
Superior alternatives for link-time culling should be used instead.
Build characteristics for inclink vs thinarc, on a small powerpc64le
pseries VM with a modest .config:
inclink thinarc
sizes
vmlinux 15 618 680 15 625 028
sum of all built-in.o 56 091 808 1 054 334
sum excluding root built-in.o 151 430
find -name built-in.o | xargs rm ; time make vmlinux
real 22.772s 21.143s
user 13.280s 13.430s
sys 4.310s 2.750s
- Final kernel pulled in only about 6K more, which shows how
ineffective the object file culling is.
- Build performance looks improved due to less pagecache activity.
On IO constrained systems it could be a bigger win.
- Build size saving is significant.
Side note, the toochain understands archives, so there's some tricks,
$ ar t built-in.o # list all files you linked with
$ size built-in.o # and their sizes
$ objdump -d built-in.o # disassembly (unrelocated) with filenames
Implementation by sfr, minor tweaks by npiggin.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-08-24 19:29:19 +07:00
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local objects
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2012-05-05 15:18:41 +07:00
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if [ "${SRCARCH}" != "um" ]; then
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2018-02-10 21:25:03 +07:00
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objects="--whole-archive \
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2019-01-17 07:10:03 +07:00
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${KBUILD_VMLINUX_INIT} \
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${KBUILD_VMLINUX_MAIN} \
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2018-02-10 21:25:03 +07:00
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--no-whole-archive \
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--start-group \
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${KBUILD_VMLINUX_LIBS} \
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--end-group \
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${1}"
|
kbuild: allow architectures to use thin archives instead of ld -r
ld -r is an incremental link used to create built-in.o files in build
subdirectories. It produces relocatable object files containing all
its input files, and these are are then pulled together and relocated
in the final link. Aside from the bloat, this constrains the final
link relocations, which has bitten large powerpc builds with
unresolvable relocations in the final link.
Alan Modra has recommended the kernel use thin archives for linking.
This is an alternative and means that the linker has more information
available to it when it links the kernel.
This patch enables a config option architectures can select, which
causes all built-in.o files to be built as thin archives. built-in.o
files in subdirectories do not get symbol table or index attached,
which improves speed and size. The final link pass creates a
built-in.o archive in the root output directory which includes the
symbol table and index. The linker then uses takes this file to link.
The --whole-archive linker option is required, because the linker now
has visibility to every individual object file, and it will otherwise
just completely avoid including those without external references
(consider a file with EXPORT_SYMBOL or initcall or hardware exceptions
as its only entry points). The traditional built works "by luck" as
built-in.o files are large enough that they're going to get external
references. However this optimisation is unpredictable for the kernel
(due to above external references), ineffective at culling unused, and
costly because the .o files have to be searched for references.
Superior alternatives for link-time culling should be used instead.
Build characteristics for inclink vs thinarc, on a small powerpc64le
pseries VM with a modest .config:
inclink thinarc
sizes
vmlinux 15 618 680 15 625 028
sum of all built-in.o 56 091 808 1 054 334
sum excluding root built-in.o 151 430
find -name built-in.o | xargs rm ; time make vmlinux
real 22.772s 21.143s
user 13.280s 13.430s
sys 4.310s 2.750s
- Final kernel pulled in only about 6K more, which shows how
ineffective the object file culling is.
- Build performance looks improved due to less pagecache activity.
On IO constrained systems it could be a bigger win.
- Build size saving is significant.
Side note, the toochain understands archives, so there's some tricks,
$ ar t built-in.o # list all files you linked with
$ size built-in.o # and their sizes
$ objdump -d built-in.o # disassembly (unrelocated) with filenames
Implementation by sfr, minor tweaks by npiggin.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-08-24 19:29:19 +07:00
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|
2018-08-24 06:20:39 +07:00
|
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${LD} ${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux} -o ${2} \
|
kbuild: allow architectures to use thin archives instead of ld -r
ld -r is an incremental link used to create built-in.o files in build
subdirectories. It produces relocatable object files containing all
its input files, and these are are then pulled together and relocated
in the final link. Aside from the bloat, this constrains the final
link relocations, which has bitten large powerpc builds with
unresolvable relocations in the final link.
Alan Modra has recommended the kernel use thin archives for linking.
This is an alternative and means that the linker has more information
available to it when it links the kernel.
This patch enables a config option architectures can select, which
causes all built-in.o files to be built as thin archives. built-in.o
files in subdirectories do not get symbol table or index attached,
which improves speed and size. The final link pass creates a
built-in.o archive in the root output directory which includes the
symbol table and index. The linker then uses takes this file to link.
The --whole-archive linker option is required, because the linker now
has visibility to every individual object file, and it will otherwise
just completely avoid including those without external references
(consider a file with EXPORT_SYMBOL or initcall or hardware exceptions
as its only entry points). The traditional built works "by luck" as
built-in.o files are large enough that they're going to get external
references. However this optimisation is unpredictable for the kernel
(due to above external references), ineffective at culling unused, and
costly because the .o files have to be searched for references.
Superior alternatives for link-time culling should be used instead.
Build characteristics for inclink vs thinarc, on a small powerpc64le
pseries VM with a modest .config:
inclink thinarc
sizes
vmlinux 15 618 680 15 625 028
sum of all built-in.o 56 091 808 1 054 334
sum excluding root built-in.o 151 430
find -name built-in.o | xargs rm ; time make vmlinux
real 22.772s 21.143s
user 13.280s 13.430s
sys 4.310s 2.750s
- Final kernel pulled in only about 6K more, which shows how
ineffective the object file culling is.
- Build performance looks improved due to less pagecache activity.
On IO constrained systems it could be a bigger win.
- Build size saving is significant.
Side note, the toochain understands archives, so there's some tricks,
$ ar t built-in.o # list all files you linked with
$ size built-in.o # and their sizes
$ objdump -d built-in.o # disassembly (unrelocated) with filenames
Implementation by sfr, minor tweaks by npiggin.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-08-24 19:29:19 +07:00
|
|
|
-T ${lds} ${objects}
|
2012-05-05 15:18:41 +07:00
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else
|
2018-02-10 21:25:03 +07:00
|
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objects="-Wl,--whole-archive \
|
2019-01-17 07:10:03 +07:00
|
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${KBUILD_VMLINUX_INIT} \
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${KBUILD_VMLINUX_MAIN} \
|
2018-02-10 21:25:03 +07:00
|
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-Wl,--no-whole-archive \
|
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-Wl,--start-group \
|
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${KBUILD_VMLINUX_LIBS} \
|
|
|
|
-Wl,--end-group \
|
|
|
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${1}"
|
kbuild: allow architectures to use thin archives instead of ld -r
ld -r is an incremental link used to create built-in.o files in build
subdirectories. It produces relocatable object files containing all
its input files, and these are are then pulled together and relocated
in the final link. Aside from the bloat, this constrains the final
link relocations, which has bitten large powerpc builds with
unresolvable relocations in the final link.
Alan Modra has recommended the kernel use thin archives for linking.
This is an alternative and means that the linker has more information
available to it when it links the kernel.
This patch enables a config option architectures can select, which
causes all built-in.o files to be built as thin archives. built-in.o
files in subdirectories do not get symbol table or index attached,
which improves speed and size. The final link pass creates a
built-in.o archive in the root output directory which includes the
symbol table and index. The linker then uses takes this file to link.
The --whole-archive linker option is required, because the linker now
has visibility to every individual object file, and it will otherwise
just completely avoid including those without external references
(consider a file with EXPORT_SYMBOL or initcall or hardware exceptions
as its only entry points). The traditional built works "by luck" as
built-in.o files are large enough that they're going to get external
references. However this optimisation is unpredictable for the kernel
(due to above external references), ineffective at culling unused, and
costly because the .o files have to be searched for references.
Superior alternatives for link-time culling should be used instead.
Build characteristics for inclink vs thinarc, on a small powerpc64le
pseries VM with a modest .config:
inclink thinarc
sizes
vmlinux 15 618 680 15 625 028
sum of all built-in.o 56 091 808 1 054 334
sum excluding root built-in.o 151 430
find -name built-in.o | xargs rm ; time make vmlinux
real 22.772s 21.143s
user 13.280s 13.430s
sys 4.310s 2.750s
- Final kernel pulled in only about 6K more, which shows how
ineffective the object file culling is.
- Build performance looks improved due to less pagecache activity.
On IO constrained systems it could be a bigger win.
- Build size saving is significant.
Side note, the toochain understands archives, so there's some tricks,
$ ar t built-in.o # list all files you linked with
$ size built-in.o # and their sizes
$ objdump -d built-in.o # disassembly (unrelocated) with filenames
Implementation by sfr, minor tweaks by npiggin.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-08-24 19:29:19 +07:00
|
|
|
|
2018-02-10 21:25:03 +07:00
|
|
|
${CC} ${CFLAGS_vmlinux} -o ${2} \
|
|
|
|
-Wl,-T,${lds} \
|
|
|
|
${objects} \
|
kbuild: allow architectures to use thin archives instead of ld -r
ld -r is an incremental link used to create built-in.o files in build
subdirectories. It produces relocatable object files containing all
its input files, and these are are then pulled together and relocated
in the final link. Aside from the bloat, this constrains the final
link relocations, which has bitten large powerpc builds with
unresolvable relocations in the final link.
Alan Modra has recommended the kernel use thin archives for linking.
This is an alternative and means that the linker has more information
available to it when it links the kernel.
This patch enables a config option architectures can select, which
causes all built-in.o files to be built as thin archives. built-in.o
files in subdirectories do not get symbol table or index attached,
which improves speed and size. The final link pass creates a
built-in.o archive in the root output directory which includes the
symbol table and index. The linker then uses takes this file to link.
The --whole-archive linker option is required, because the linker now
has visibility to every individual object file, and it will otherwise
just completely avoid including those without external references
(consider a file with EXPORT_SYMBOL or initcall or hardware exceptions
as its only entry points). The traditional built works "by luck" as
built-in.o files are large enough that they're going to get external
references. However this optimisation is unpredictable for the kernel
(due to above external references), ineffective at culling unused, and
costly because the .o files have to be searched for references.
Superior alternatives for link-time culling should be used instead.
Build characteristics for inclink vs thinarc, on a small powerpc64le
pseries VM with a modest .config:
inclink thinarc
sizes
vmlinux 15 618 680 15 625 028
sum of all built-in.o 56 091 808 1 054 334
sum excluding root built-in.o 151 430
find -name built-in.o | xargs rm ; time make vmlinux
real 22.772s 21.143s
user 13.280s 13.430s
sys 4.310s 2.750s
- Final kernel pulled in only about 6K more, which shows how
ineffective the object file culling is.
- Build performance looks improved due to less pagecache activity.
On IO constrained systems it could be a bigger win.
- Build size saving is significant.
Side note, the toochain understands archives, so there's some tricks,
$ ar t built-in.o # list all files you linked with
$ size built-in.o # and their sizes
$ objdump -d built-in.o # disassembly (unrelocated) with filenames
Implementation by sfr, minor tweaks by npiggin.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-08-24 19:29:19 +07:00
|
|
|
-lutil -lrt -lpthread
|
2012-05-05 15:18:41 +07:00
|
|
|
rm -f linux
|
|
|
|
fi
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
# Create ${2} .o file with all symbols from the ${1} object file
|
|
|
|
kallsyms()
|
|
|
|
{
|
|
|
|
info KSYM ${2}
|
|
|
|
local kallsymopt;
|
|
|
|
|
|
|
|
if [ -n "${CONFIG_KALLSYMS_ALL}" ]; then
|
2012-09-07 04:11:25 +07:00
|
|
|
kallsymopt="${kallsymopt} --all-symbols"
|
2012-05-05 15:18:41 +07:00
|
|
|
fi
|
|
|
|
|
2016-03-16 04:58:12 +07:00
|
|
|
if [ -n "${CONFIG_KALLSYMS_ABSOLUTE_PERCPU}" ]; then
|
2014-03-17 10:35:46 +07:00
|
|
|
kallsymopt="${kallsymopt} --absolute-percpu"
|
|
|
|
fi
|
|
|
|
|
kallsyms: add support for relative offsets in kallsyms address table
Similar to how relative extables are implemented, it is possible to emit
the kallsyms table in such a way that it contains offsets relative to
some anchor point in the kernel image rather than absolute addresses.
On 64-bit architectures, it cuts the size of the kallsyms address table
in half, since offsets between kernel symbols can typically be expressed
in 32 bits. This saves several hundreds of kilobytes of permanent
.rodata on average. In addition, the kallsyms address table is no
longer subject to dynamic relocation when CONFIG_RELOCATABLE is in
effect, so the relocation work done after decompression now doesn't have
to do relocation updates for all these values. This saves up to 24
bytes (i.e., the size of a ELF64 RELA relocation table entry) per value,
which easily adds up to a couple of megabytes of uncompressed __init
data on ppc64 or arm64. Even if these relocation entries typically
compress well, the combined size reduction of 2.8 MB uncompressed for a
ppc64_defconfig build (of which 2.4 MB is __init data) results in a ~500
KB space saving in the compressed image.
Since it is useful for some architectures (like x86) to retain the
ability to emit absolute values as well, this patch also adds support
for capturing both absolute and relative values when
KALLSYMS_ABSOLUTE_PERCPU is in effect, by emitting absolute per-cpu
addresses as positive 32-bit values, and addresses relative to the
lowest encountered relative symbol as negative values, which are
subtracted from the runtime address of this base symbol to produce the
actual address.
Support for the above is enabled by default for all architectures except
IA-64 and Tile-GX, whose symbols are too far apart to capture in this
manner.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 04:58:19 +07:00
|
|
|
if [ -n "${CONFIG_KALLSYMS_BASE_RELATIVE}" ]; then
|
|
|
|
kallsymopt="${kallsymopt} --base-relative"
|
|
|
|
fi
|
|
|
|
|
2012-05-09 00:53:46 +07:00
|
|
|
local aflags="${KBUILD_AFLAGS} ${KBUILD_AFLAGS_KERNEL} \
|
|
|
|
${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS}"
|
2012-05-05 15:18:41 +07:00
|
|
|
|
2016-02-05 17:25:05 +07:00
|
|
|
local afile="`basename ${2} .o`.S"
|
|
|
|
|
|
|
|
${NM} -n ${1} | scripts/kallsyms ${kallsymopt} > ${afile}
|
|
|
|
${CC} ${aflags} -c -o ${2} ${afile}
|
2012-05-05 15:18:41 +07:00
|
|
|
}
|
|
|
|
|
|
|
|
# Create map file with all symbols from ${1}
|
|
|
|
# See mksymap for additional details
|
|
|
|
mksysmap()
|
|
|
|
{
|
|
|
|
${CONFIG_SHELL} "${srctree}/scripts/mksysmap" ${1} ${2}
|
|
|
|
}
|
|
|
|
|
2012-05-29 00:32:28 +07:00
|
|
|
sortextable()
|
|
|
|
{
|
|
|
|
${objtree}/scripts/sortextable ${1}
|
|
|
|
}
|
|
|
|
|
2012-05-05 15:18:41 +07:00
|
|
|
# Delete output files in case of error
|
|
|
|
cleanup()
|
|
|
|
{
|
|
|
|
rm -f .tmp_System.map
|
|
|
|
rm -f .tmp_kallsyms*
|
|
|
|
rm -f .tmp_vmlinux*
|
|
|
|
rm -f System.map
|
|
|
|
rm -f vmlinux
|
|
|
|
rm -f vmlinux.o
|
|
|
|
}
|
|
|
|
|
2015-05-07 07:36:04 +07:00
|
|
|
on_exit()
|
|
|
|
{
|
|
|
|
if [ $? -ne 0 ]; then
|
|
|
|
cleanup
|
|
|
|
fi
|
|
|
|
}
|
|
|
|
trap on_exit EXIT
|
|
|
|
|
|
|
|
on_signals()
|
|
|
|
{
|
|
|
|
exit 1
|
|
|
|
}
|
|
|
|
trap on_signals HUP INT QUIT TERM
|
|
|
|
|
2012-05-05 15:18:41 +07:00
|
|
|
#
|
|
|
|
#
|
|
|
|
# Use "make V=1" to debug this script
|
|
|
|
case "${KBUILD_VERBOSE}" in
|
|
|
|
*1*)
|
|
|
|
set -x
|
|
|
|
;;
|
|
|
|
esac
|
|
|
|
|
|
|
|
if [ "$1" = "clean" ]; then
|
|
|
|
cleanup
|
|
|
|
exit 0
|
|
|
|
fi
|
|
|
|
|
|
|
|
# We need access to CONFIG_ symbols
|
2013-02-25 19:47:53 +07:00
|
|
|
case "${KCONFIG_CONFIG}" in
|
|
|
|
*/*)
|
|
|
|
. "${KCONFIG_CONFIG}"
|
|
|
|
;;
|
|
|
|
*)
|
|
|
|
# Force using a file from the current directory
|
|
|
|
. "./${KCONFIG_CONFIG}"
|
|
|
|
esac
|
2012-05-05 15:18:41 +07:00
|
|
|
|
|
|
|
# Update version
|
|
|
|
info GEN .version
|
2017-09-22 12:31:13 +07:00
|
|
|
if [ -r .version ]; then
|
|
|
|
VERSION=$(expr 0$(cat .version) + 1)
|
|
|
|
echo $VERSION > .version
|
2012-05-05 15:18:41 +07:00
|
|
|
else
|
2017-09-22 12:31:13 +07:00
|
|
|
rm -f .version
|
|
|
|
echo 1 > .version
|
2012-05-05 15:18:41 +07:00
|
|
|
fi;
|
|
|
|
|
|
|
|
# final build of init/
|
2018-02-21 11:25:07 +07:00
|
|
|
${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init
|
2012-05-05 15:18:41 +07:00
|
|
|
|
2016-11-23 23:41:43 +07:00
|
|
|
#link vmlinux.o
|
|
|
|
info LD vmlinux.o
|
|
|
|
modpost_link vmlinux.o
|
|
|
|
|
|
|
|
# modpost vmlinux.o to check for section mismatches
|
|
|
|
${MAKE} -f "${srctree}/scripts/Makefile.modpost" vmlinux.o
|
|
|
|
|
2012-05-05 15:18:41 +07:00
|
|
|
kallsymso=""
|
|
|
|
kallsyms_vmlinux=""
|
|
|
|
if [ -n "${CONFIG_KALLSYMS}" ]; then
|
|
|
|
|
|
|
|
# kallsyms support
|
|
|
|
# Generate section listing all symbols and add it into vmlinux
|
|
|
|
# It's a three step process:
|
|
|
|
# 1) Link .tmp_vmlinux1 so it has all symbols and sections,
|
|
|
|
# but __kallsyms is empty.
|
|
|
|
# Running kallsyms on that gives us .tmp_kallsyms1.o with
|
|
|
|
# the right size
|
|
|
|
# 2) Link .tmp_vmlinux2 so it now has a __kallsyms section of
|
|
|
|
# the right size, but due to the added section, some
|
|
|
|
# addresses have shifted.
|
|
|
|
# From here, we generate a correct .tmp_kallsyms2.o
|
2016-11-23 23:41:37 +07:00
|
|
|
# 3) That link may have expanded the kernel image enough that
|
|
|
|
# more linker branch stubs / trampolines had to be added, which
|
|
|
|
# introduces new names, which further expands kallsyms. Do another
|
|
|
|
# pass if that is the case. In theory it's possible this results
|
|
|
|
# in even more stubs, but unlikely.
|
|
|
|
# KALLSYMS_EXTRA_PASS=1 may also used to debug or work around
|
|
|
|
# other bugs.
|
|
|
|
# 4) The correct ${kallsymso} is linked into the final vmlinux.
|
2012-05-05 15:18:41 +07:00
|
|
|
#
|
|
|
|
# a) Verify that the System.map from vmlinux matches the map from
|
|
|
|
# ${kallsymso}.
|
|
|
|
|
|
|
|
kallsymso=.tmp_kallsyms2.o
|
|
|
|
kallsyms_vmlinux=.tmp_vmlinux2
|
|
|
|
|
|
|
|
# step 1
|
|
|
|
vmlinux_link "" .tmp_vmlinux1
|
|
|
|
kallsyms .tmp_vmlinux1 .tmp_kallsyms1.o
|
|
|
|
|
|
|
|
# step 2
|
|
|
|
vmlinux_link .tmp_kallsyms1.o .tmp_vmlinux2
|
|
|
|
kallsyms .tmp_vmlinux2 .tmp_kallsyms2.o
|
|
|
|
|
2016-11-23 23:41:37 +07:00
|
|
|
# step 3
|
kbuild: Use ls(1) instead of stat(1) to obtain file size
stat(1) is not standardized and different implementations have their own
(conflicting) flags for querying the size of a file.
ls(1) provides the same information (value of st.st_size) in the 5th
column, except when the file is a character or block device. This output
is standardized[0]. The -n option turns on -l, which writes lines
formatted like
"%s %u %s %s %u %s %s\n", <file mode>, <number of links>,
<owner name>, <group name>, <size>, <date and time>,
<pathname>
but instead of writing the <owner name> and <group name>, it writes the
numeric owner and group IDs (this avoids /etc/passwd and /etc/group
lookups as well as potential field splitting issues).
The <size> field is specified as "the value that would be returned for
the file in the st_size field of struct stat".
To avoid duplicating logic in several locations in the tree, create
scripts/file-size.sh and update callers to use that instead of stat(1).
[0] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/ls.html#tag_20_73_10
Signed-off-by: Michael Forney <forney@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-19 07:54:02 +07:00
|
|
|
size1=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" .tmp_kallsyms1.o)
|
|
|
|
size2=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" .tmp_kallsyms2.o)
|
2016-11-23 23:41:37 +07:00
|
|
|
|
|
|
|
if [ $size1 -ne $size2 ] || [ -n "${KALLSYMS_EXTRA_PASS}" ]; then
|
2012-05-05 15:18:41 +07:00
|
|
|
kallsymso=.tmp_kallsyms3.o
|
|
|
|
kallsyms_vmlinux=.tmp_vmlinux3
|
|
|
|
|
|
|
|
vmlinux_link .tmp_kallsyms2.o .tmp_vmlinux3
|
|
|
|
|
|
|
|
kallsyms .tmp_vmlinux3 .tmp_kallsyms3.o
|
|
|
|
fi
|
|
|
|
fi
|
|
|
|
|
|
|
|
info LD vmlinux
|
|
|
|
vmlinux_link "${kallsymso}" vmlinux
|
|
|
|
|
2012-05-29 00:32:28 +07:00
|
|
|
if [ -n "${CONFIG_BUILDTIME_EXTABLE_SORT}" ]; then
|
|
|
|
info SORTEX vmlinux
|
|
|
|
sortextable vmlinux
|
|
|
|
fi
|
|
|
|
|
2012-05-05 15:18:41 +07:00
|
|
|
info SYSMAP System.map
|
|
|
|
mksysmap vmlinux System.map
|
|
|
|
|
|
|
|
# step a (see comment above)
|
|
|
|
if [ -n "${CONFIG_KALLSYMS}" ]; then
|
|
|
|
mksysmap ${kallsyms_vmlinux} .tmp_System.map
|
|
|
|
|
|
|
|
if ! cmp -s System.map .tmp_System.map; then
|
2012-07-08 04:04:40 +07:00
|
|
|
echo >&2 Inconsistent kallsyms data
|
2012-08-10 16:55:11 +07:00
|
|
|
echo >&2 Try "make KALLSYMS_EXTRA_PASS=1" as a workaround
|
2012-05-05 15:18:41 +07:00
|
|
|
exit 1
|
|
|
|
fi
|
|
|
|
fi
|