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>

32 files changed, 32 insertions, 0 deletions

diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index c4e6fe3..6519741 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 # Makefile for making ELF bootable images for booting on CHRP
 # using Open Firmware.
 #
diff --git a/arch/powerpc/boot/cpm-serial.c b/arch/powerpc/boot/cpm-serial.c
index 19dc15a..dfb5682 100644
--- a/arch/powerpc/boot/cpm-serial.c
+++ b/arch/powerpc/boot/cpm-serial.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * CPM serial console support.
  *
diff --git a/arch/powerpc/boot/cuboot.h b/arch/powerpc/boot/cuboot.h
index cd2aa7f..c2b2c58 100644
--- a/arch/powerpc/boot/cuboot.h
+++ b/arch/powerpc/boot/cuboot.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_CUBOOT_H_
 #define _PPC_BOOT_CUBOOT_H_
 
diff --git a/arch/powerpc/boot/dcr.h b/arch/powerpc/boot/dcr.h
index bf8f4ed..334ab8b 100644
--- a/arch/powerpc/boot/dcr.h
+++ b/arch/powerpc/boot/dcr.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_DCR_H_
 #define _PPC_BOOT_DCR_H_
 
diff --git a/arch/powerpc/boot/dts/virtex440-ml510.dts b/arch/powerpc/boot/dts/virtex440-ml510.dts
index 81a8dc2..81201d3 100644
--- a/arch/powerpc/boot/dts/virtex440-ml510.dts
+++ b/arch/powerpc/boot/dts/virtex440-ml510.dts
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Xilinx ML510 Reference Design support
  *
diff --git a/arch/powerpc/boot/elf.h b/arch/powerpc/boot/elf.h
index 1941bc5..f6aa7c2 100644
--- a/arch/powerpc/boot/elf.h
+++ b/arch/powerpc/boot/elf.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_ELF_H_
 #define _PPC_BOOT_ELF_H_
 
diff --git a/arch/powerpc/boot/epapr-wrapper.c b/arch/powerpc/boot/epapr-wrapper.c
index c101910..01262f5 100644
--- a/arch/powerpc/boot/epapr-wrapper.c
+++ b/arch/powerpc/boot/epapr-wrapper.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 extern void epapr_platform_init(unsigned long r3, unsigned long r4,
 				unsigned long r5, unsigned long r6,
 				unsigned long r7);
diff --git a/arch/powerpc/boot/fixed-head.S b/arch/powerpc/boot/fixed-head.S
index 8e14cd9..4346c75 100644
--- a/arch/powerpc/boot/fixed-head.S
+++ b/arch/powerpc/boot/fixed-head.S
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 	.text
 	.global _zimage_start
 _zimage_start:
diff --git a/arch/powerpc/boot/fsl-soc.h b/arch/powerpc/boot/fsl-soc.h
index 5da26fc..00b2cb8 100644
--- a/arch/powerpc/boot/fsl-soc.h
+++ b/arch/powerpc/boot/fsl-soc.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_FSL_SOC_H_
 #define _PPC_BOOT_FSL_SOC_H_
 
diff --git a/arch/powerpc/boot/io.h b/arch/powerpc/boot/io.h
index 394da55..5c6f90c 100644
--- a/arch/powerpc/boot/io.h
+++ b/arch/powerpc/boot/io.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _IO_H
 #define _IO_H
 
diff --git a/arch/powerpc/boot/libfdt_env.h b/arch/powerpc/boot/libfdt_env.h
index 7e3789e..f52c31b 100644
--- a/arch/powerpc/boot/libfdt_env.h
+++ b/arch/powerpc/boot/libfdt_env.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _ARCH_POWERPC_BOOT_LIBFDT_ENV_H
 #define _ARCH_POWERPC_BOOT_LIBFDT_ENV_H
 
diff --git a/arch/powerpc/boot/mktree.c b/arch/powerpc/boot/mktree.c
index e2ae243..dc603f3 100644
--- a/arch/powerpc/boot/mktree.c
+++ b/arch/powerpc/boot/mktree.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Makes a tree bootable image for IBM Evaluation boards.
  * Basically, just take a zImage, skip the ELF header, and stuff
diff --git a/arch/powerpc/boot/motload-head.S b/arch/powerpc/boot/motload-head.S
index 41cabb4..826dad0 100644
--- a/arch/powerpc/boot/motload-head.S
+++ b/arch/powerpc/boot/motload-head.S
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #include "ppc_asm.h"
 
 	.text
diff --git a/arch/powerpc/boot/mpc52xx-psc.c b/arch/powerpc/boot/mpc52xx-psc.c
index d4cb4e4..c2c0863 100644
--- a/arch/powerpc/boot/mpc52xx-psc.c
+++ b/arch/powerpc/boot/mpc52xx-psc.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * MPC5200 PSC serial console support.
  *
diff --git a/arch/powerpc/boot/mpc8xx.h b/arch/powerpc/boot/mpc8xx.h
index 3f59901..3852ed9 100644
--- a/arch/powerpc/boot/mpc8xx.h
+++ b/arch/powerpc/boot/mpc8xx.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_MPC8xx_H_
 #define _PPC_BOOT_MPC8xx_H_
 
diff --git a/arch/powerpc/boot/ns16550.c b/arch/powerpc/boot/ns16550.c
index 8c9ead9..b0da446 100644
--- a/arch/powerpc/boot/ns16550.c
+++ b/arch/powerpc/boot/ns16550.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * 16550 serial console support.
  *
diff --git a/arch/powerpc/boot/of.h b/arch/powerpc/boot/of.h
index 53f8f27..31b2f5d 100644
--- a/arch/powerpc/boot/of.h
+++ b/arch/powerpc/boot/of.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_OF_H_
 #define _PPC_BOOT_OF_H_
 
diff --git a/arch/powerpc/boot/planetcore.h b/arch/powerpc/boot/planetcore.h
index d53c733..5311db0 100644
--- a/arch/powerpc/boot/planetcore.h
+++ b/arch/powerpc/boot/planetcore.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_PLANETCORE_H_
 #define _PPC_BOOT_PLANETCORE_H_
 
diff --git a/arch/powerpc/boot/pq2.h b/arch/powerpc/boot/pq2.h
index 481698c..f577b3b 100644
--- a/arch/powerpc/boot/pq2.h
+++ b/arch/powerpc/boot/pq2.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_PQ2_H_
 #define _PPC_BOOT_PQ2_H_
 
diff --git a/arch/powerpc/boot/pseries-head.S b/arch/powerpc/boot/pseries-head.S
index 6ef6e02..1b1a638 100644
--- a/arch/powerpc/boot/pseries-head.S
+++ b/arch/powerpc/boot/pseries-head.S
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #include "ppc_asm.h"
 
 	.text
diff --git a/arch/powerpc/boot/redboot.h b/arch/powerpc/boot/redboot.h
index ace0b7f..8f319b1 100644
--- a/arch/powerpc/boot/redboot.h
+++ b/arch/powerpc/boot/redboot.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_REDBOOT_H
 #define _PPC_REDBOOT_H
 
diff --git a/arch/powerpc/boot/rs6000.h b/arch/powerpc/boot/rs6000.h
index d70517c..a9d8791 100644
--- a/arch/powerpc/boot/rs6000.h
+++ b/arch/powerpc/boot/rs6000.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /* IBM RS/6000 "XCOFF" file definitions for BFD.
    Copyright (C) 1990, 1991 Free Software Foundation, Inc.
    FIXME: Can someone provide a transliteration of this name into ASCII?
diff --git a/arch/powerpc/boot/stdio.h b/arch/powerpc/boot/stdio.h
index adffc58..884d595 100644
--- a/arch/powerpc/boot/stdio.h
+++ b/arch/powerpc/boot/stdio.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_STDIO_H_
 #define _PPC_BOOT_STDIO_H_
 
diff --git a/arch/powerpc/boot/stdlib.h b/arch/powerpc/boot/stdlib.h
index 1bf01ac..0a61fcd 100644
--- a/arch/powerpc/boot/stdlib.h
+++ b/arch/powerpc/boot/stdlib.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_STDLIB_H_
 #define _PPC_BOOT_STDLIB_H_
 
diff --git a/arch/powerpc/boot/string.h b/arch/powerpc/boot/string.h
index 50091cc..3fb7117 100644
--- a/arch/powerpc/boot/string.h
+++ b/arch/powerpc/boot/string.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_STRING_H_
 #define _PPC_BOOT_STRING_H_
 #include <stddef.h>
diff --git a/arch/powerpc/boot/swab.h b/arch/powerpc/boot/swab.h
index d0e1431..11d2069 100644
--- a/arch/powerpc/boot/swab.h
+++ b/arch/powerpc/boot/swab.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PPC_BOOT_SWAB_H_
 #define _PPC_BOOT_SWAB_H_
 
diff --git a/arch/powerpc/boot/types.h b/arch/powerpc/boot/types.h
index af6b66b..8a4c418 100644
--- a/arch/powerpc/boot/types.h
+++ b/arch/powerpc/boot/types.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _TYPES_H_
 #define _TYPES_H_
 
diff --git a/arch/powerpc/boot/virtex405-head.S b/arch/powerpc/boot/virtex405-head.S
index 3edb13f..00bab7d 100644
--- a/arch/powerpc/boot/virtex405-head.S
+++ b/arch/powerpc/boot/virtex405-head.S
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #include "ppc_asm.h"
 
 	.text
diff --git a/arch/powerpc/boot/xz_config.h b/arch/powerpc/boot/xz_config.h
index 5c6afdb..e22e5b3 100644
--- a/arch/powerpc/boot/xz_config.h
+++ b/arch/powerpc/boot/xz_config.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __XZ_CONFIG_H__
 #define __XZ_CONFIG_H__
 
diff --git a/arch/powerpc/boot/zImage.coff.lds.S b/arch/powerpc/boot/zImage.coff.lds.S
index de4c9e3..1179512 100644
--- a/arch/powerpc/boot/zImage.coff.lds.S
+++ b/arch/powerpc/boot/zImage.coff.lds.S
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 OUTPUT_ARCH(powerpc:common)
 ENTRY(_zimage_start_opd)
 EXTERN(_zimage_start_opd)
diff --git a/arch/powerpc/boot/zImage.lds.S b/arch/powerpc/boot/zImage.lds.S
index f080abf..4ac1e36 100644
--- a/arch/powerpc/boot/zImage.lds.S
+++ b/arch/powerpc/boot/zImage.lds.S
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #include <asm-generic/vmlinux.lds.h>
 
 #ifdef CONFIG_PPC64_BOOT_WRAPPER
diff --git a/arch/powerpc/boot/zImage.ps3.lds.S b/arch/powerpc/boot/zImage.ps3.lds.S
index aaa469c..7b2ff2e 100644
--- a/arch/powerpc/boot/zImage.ps3.lds.S
+++ b/arch/powerpc/boot/zImage.ps3.lds.S
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 OUTPUT_ARCH(powerpc:common)
 ENTRY(_zimage_start)
 EXTERN(_zimage_start)