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

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>

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Merge branch 'next' into for-linus

Prepare input updates for 4.10 merge window.

Merge branch 'topic/error' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-fixed

Merge branch 'drm-tda998x-mali' into drm-tda998x-devel

Merge tag 'v4.8' into next

Sync up with mainline to bring in I2C host notify changes and other
updates.

Merge tag 'v4.9-rc3' into xtensa-for-next

Linux 4.9-rc3

Merge tag 'irqchip-4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

Merge the first drop of irqchip updates for 4.9 from Marc Zyngier:

- ACPI IORT core code
-

Merge tag 'irqchip-4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

Merge the first drop of irqchip updates for 4.9 from Marc Zyngier:

- ACPI IORT core code
- IORT support for the GICv3 ITS
- A few of GIC cleanups

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Merge branch 'x86/urgent' into x86/asm, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Minor overlapping changes for both merge conflicts.

Resolution work done by Stephen Rothwell was used
as a reference.

Signed-off-by: D

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Minor overlapping changes for both merge conflicts.

Resolution work done by Stephen Rothwell was used
as a reference.

Signed-off-by: David S. Miller <davem@davemloft.net>

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Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next-queued

Backmerge because too many conflicts, and also we need to get at the
latest struct fence patches from Gustavo. Requested by

Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next-queued

Backmerge because too many conflicts, and also we need to get at the
latest struct fence patches from Gustavo. Requested by Chris Wilson.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

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Merge branch 'linus' into timers/urgent, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge branch 'linus' into locking/urgent, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'v4.8-rc1' into patchwork

Linux 4.8-rc1

* tag 'v4.8-rc1': (6093 commits)
Linux 4.8-rc1
block: rename bio bi_rw to bi_opf
target: iblock_execute_sync_cache() should use bio_set_op_at

Merge tag 'v4.8-rc1' into patchwork

Linux 4.8-rc1

* tag 'v4.8-rc1': (6093 commits)
Linux 4.8-rc1
block: rename bio bi_rw to bi_opf
target: iblock_execute_sync_cache() should use bio_set_op_attrs()
mm: make __swap_writepage() use bio_set_op_attrs()
block/mm: make bdev_ops->rw_page() take a bool for read/write
fs: return EPERM on immutable inode
ramoops: use persistent_ram_free() instead of kfree() for freeing prz
ramoops: use DT reserved-memory bindings
NTB: ntb_hw_intel: use local variable pdev
NTB: ntb_hw_intel: show BAR size in debugfs info
ntb_test: Add a selftest script for the NTB subsystem
ntb_perf: clear link_is_up flag when the link goes down.
ntb_pingpong: Add a debugfs file to get the ping count
ntb_tool: Add link status and files to debugfs
ntb_tool: Postpone memory window initialization for the user
ntb_perf: Wait for link before running test
ntb_perf: Return results by reading the run file
ntb_perf: Improve thread handling to increase robustness
ntb_perf: Schedule based on time not on performance
ntb_transport: Check the number of spads the hardware supports
...

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Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull more vfs updates from Al Viro:
"Assorted cleanups and fixes.

In the "trivial API change" department - ->

Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull more vfs updates from Al Viro:
"Assorted cleanups and fixes.

In the "trivial API change" department - ->d_compare() losing 'parent'
argument"

* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
cachefiles: Fix race between inactivating and culling a cache object
9p: use clone_fid()
9p: fix braino introduced in "9p: new helper - v9fs_parent_fid()"
vfs: make dentry_needs_remove_privs() internal
vfs: remove file_needs_remove_privs()
vfs: fix deadlock in file_remove_privs() on overlayfs
get rid of 'parent' argument of ->d_compare()
cifs, msdos, vfat, hfs+: don't bother with parent in ->d_compare()
affs ->d_compare(): don't bother with ->d_inode
fold _d_rehash() and __d_rehash() together
fold dentry_rcuwalk_invalidate() into its only remaining caller

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get rid of 'parent' argument of ->d_compare()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Merge remote-tracking branch 'linusw-gpio/for-next' into devm_gpiochip

Base for demv_gpiochip_add_data() and devm_gpiochip_remove().

Merge branch 'next' into for-linus

Prepare first round of input updates for 3.20.

Merge tag 'v3.19-rc4' into next

Merge with mainline to bring in the latest thermal and other changes.

Merge branches 'arm/omap', 'arm/msm', 'arm/rockchip', 'arm/renesas', 'arm/smmu', 'x86/vt-d', 'x86/amd' and 'core' into next

Conflicts:
drivers/iommu/arm-smmu.c

Merge branch 'topic/usb-resume' into for-next

Merge the proper mixer resume support for quirk codes.

Merge tag 'v3.18-rc4' into regulator-max77686

Linux 3.18-rc4

Merge tag 'v3.18-rc4' into regulator-max77802

Linux 3.18-rc4

Merge branch 'core' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

This branch contains a couple of changes that will conflict with the
Tegra SMMU driver rewrite. Since the driver is la

Merge branch 'core' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

This branch contains a couple of changes that will conflict with the
Tegra SMMU driver rewrite. Since the driver is largely rewritten the
conflict resolution is non-trivial.

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Merge tag 'tags/phy-dt-header' into mvebu/dt-usb_phy

shared header file which will be referenced from both
PHY driver and its associated Device Tree node(s)

Merge branch 'master' into for-3.19

Pull in to receive 54ef6df3f3f1 ("rcu: Provide counterpart to
rcu_dereference() for non-RCU situations").

Signed-off-by: Tejun Heo <tj@kernel.org>