linux/arch/mips/Kconfig.debug
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

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# SPDX-License-Identifier: GPL-2.0
menu "Kernel hacking"
config TRACE_IRQFLAGS_SUPPORT
bool
default y
source "lib/Kconfig.debug"
config EARLY_PRINTK
bool "Early printk" if EXPERT
depends on SYS_HAS_EARLY_PRINTK
default y
help
This option enables special console drivers which allow the kernel
to print messages very early in the bootup process.
This is useful for kernel debugging when your machine crashes very
early before the console code is initialized. For normal operation,
it is not recommended because it looks ugly on some machines and
doesn't cooperate with an X server. You should normally say N here,
unless you want to debug such a crash.
config EARLY_PRINTK_8250
bool
depends on EARLY_PRINTK && USE_GENERIC_EARLY_PRINTK_8250
default y
help
"8250/16550 and compatible serial early printk driver"
If you say Y here, it will be possible to use a 8250/16550 serial
port as the boot console.
config USE_GENERIC_EARLY_PRINTK_8250
bool
config CMDLINE_BOOL
bool "Built-in kernel command line"
default n
help
For most systems, it is firmware or second stage bootloader that
by default specifies the kernel command line options. However,
it might be necessary or advantageous to either override the
default kernel command line or add a few extra options to it.
For such cases, this option allows you to hardcode your own
command line options directly into the kernel. For that, you
should choose 'Y' here, and fill in the extra boot arguments
in CONFIG_CMDLINE.
The built-in options will be concatenated to the default command
line if CMDLINE_OVERRIDE is set to 'N'. Otherwise, the default
command line will be ignored and replaced by the built-in string.
Most MIPS systems will normally expect 'N' here and rely upon
the command line from the firmware or the second-stage bootloader.
config CMDLINE
string "Default kernel command string"
depends on CMDLINE_BOOL
default ""
help
On some platforms, there is currently no way for the boot loader to
pass arguments to the kernel. For these platforms, and for the cases
when you want to add some extra options to the command line or ignore
the default command line, you can supply some command-line options at
build time by entering them here. In other cases you can specify
kernel args so that you don't have to set them up in board prom
initialization routines.
For more information, see the CMDLINE_BOOL and CMDLINE_OVERRIDE
options.
config CMDLINE_OVERRIDE
bool "Built-in command line overrides firmware arguments"
default n
depends on CMDLINE_BOOL
help
By setting this option to 'Y' you will have your kernel ignore
command line arguments from firmware or second stage bootloader.
Instead, the built-in command line will be used exclusively.
Normally, you will choose 'N' here.
config SB1XXX_CORELIS
bool "Corelis Debugger"
depends on SIBYTE_SB1xxx_SOC
select DEBUG_INFO if !COMPILE_TEST
help
Select compile flags that produce code that can be processed by the
Corelis mksym utility and UDB Emulator.
config DEBUG_ZBOOT
bool "Enable compressed kernel support debugging"
depends on DEBUG_KERNEL && SYS_SUPPORTS_ZBOOT
default n
help
If you want to add compressed kernel support to a new board, and the
board supports uart16550 compatible serial port, please select
SYS_SUPPORTS_ZBOOT_UART16550 for your board and enable this option to
debug it.
If your board doesn't support uart16550 compatible serial port, you
can try to select SYS_SUPPORTS_ZBOOT and use the other methods to
debug it. for example, add a new serial port support just as
arch/mips/boot/compressed/uart-16550.c does.
After the compressed kernel support works, please disable this option
to reduce the kernel image size and speed up the booting procedure a
little.
config SPINLOCK_TEST
bool "Enable spinlock timing tests in debugfs"
depends on DEBUG_FS
default n
help
Add several files to the debugfs to test spinlock speed.
config SCACHE_DEBUGFS
bool "L2 cache debugfs entries"
depends on DEBUG_FS
help
Enable this to allow parts of the L2 cache configuration, such as
whether or not prefetching is enabled, to be exposed to userland
via debugfs.
If unsure, say N.
menuconfig MIPS_CPS_NS16550
bool "CPS SMP NS16550 UART output"
depends on MIPS_CPS
help
Output debug information via an ns16550 compatible UART if exceptions
occur early in the boot process of a secondary core.
if MIPS_CPS_NS16550
config MIPS_CPS_NS16550_BASE
hex "UART Base Address"
default 0x1b0003f8 if MIPS_MALTA
help
The base address of the ns16550 compatible UART on which to output
debug information from the early stages of core startup.
config MIPS_CPS_NS16550_SHIFT
int "UART Register Shift"
default 0 if MIPS_MALTA
help
The number of bits to shift ns16550 register indices by in order to
form their addresses. That is, log base 2 of the span between
adjacent ns16550 registers in the system.
endif # MIPS_CPS_NS16550
endmenu