Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Uses '!RWSEM_GENERIC_SPINLOCK' in place of 'Optimized asm/rwsem.h' as
Kconfig for 'rwsem-optimized': the new Kconfig expresses this feature
equivalently, while also enabling the script 'features-refresh.sh' to
operate on the corresponding arch support status file. Also refreshes
the status matrix by using the script 'features-refresh.sh'.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Commit 6077776b split 'HAVE_BPF_JIT' into cBPF and eBPF variant.
Adds arch support status files for the new variants, and removes the
status file corresponding to 'HAVE_BPT_JIT'. The new status matrices
were auto-generated using the script 'features-refresh.sh'.
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Now that the script 'features-refresh.sh' is available, uses this script
to refresh all the arch-support.txt files in place.
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Provides the script:

	Documentation/features/scripts/features-refresh.sh

which operates on the arch-support.txt files and refreshes them in place.

This way [1],

   "[...] we soft- decouple the refreshing of the entries from the
    introduction of the features, while still making it all easy to
    keep sync and to extend."

[1] http://lkml.kernel.org/r/20180328122211.GA25420@andreaSuggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Make the description of the kernel command line option "blkdevparts"
a bit more flowing and readable.

Fix a few typos.
Add the optional <size> and <offset> suffixes.
Note that size can be "-" to indicate all of the remaining space.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Cai Zhiyong <caizhiyong@huawei.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Update vfio_add_group_dev description to match the current API.
Signed-off-by: Dong Bo <dongbo4@huawei.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This came up in discussions when reviewing drm patches.
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Remove implementation details from sysfs parameter descriptions.
Also move the paragraph discussing fragmentation issues and their possible
solution to the "Design" section.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Make the description of stable_node_chains_prune_millisecs sysfs parameter
less implementation aware and add a few words about this parameter in the
"Design" section.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The description of "max_page_sharing" sysfs attribute includes lots of
implementation details that more naturally belong in the "Design"
section.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Include the KSM description from the source code comment, add a subsection
about reverse mapping and include kernel-doc references for KSM data
structures.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Aside from the formatting:
* fixed typos
* added section and sub-section headers
* moved ksmd overview after the description of KSM origins
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The existing comment provides a good overview of KSM implementation. Let's
update it to reflect recent additions of "chain" and "dup" variants of the
stable tree nodes and mark it as "DOC:" for inclusion into the KSM
documentation.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Using incorrect :functions: syntax (extra space) causes an odd kernel-doc
warning, so fix that.

Documentation/driver-api/device_connection.rst:42: ERROR: Error in "kernel-doc" directive:
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Rearrange some kernel-api chapters and sections to group them
together better.

- move Bit Operations from Basic C Library Functions to Basic
  Kernel Library Functions (now adjacent to Bitmap Operations since
  they are not typical C library functions)

- move Sorting from Math Functions to Basic Kernel Library Functions
  since sort functions are more Basic than Math Functions

- move Text Searching from Math Functions to Basic Kernel Library
  Functions (keep Sorting and Searching close to each other)

- combine CRC and Math functions together into the (newly named)
  CRC and Math Functions chapter
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

  Merge -rc2 to pick up the changes to
  Documentation/core-api/kernel-api.rst that hit mainline via the
  networking tree.  In their absence, subsequent patches cannot be
  applied.

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Several documents in Documentation/vm fit quite well into the "admin/user
guide" category. The documents that don't overload the reader with lots of
implementation details and provide coherent description of certain feature
can be moved to Documentation/admin-guide/mm.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

"pagemap from the Userspace Perspective" is not very descriptive for
unaware readers. Since the document describes how to examine a process page
tables, let's title it "Examining Process Page Tables"
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The hugetlbpage describes hugetlbfs from the user perspective and newer
hugetlbfs_reserv document targets kernel developers. Hence the section
about hugetlbfs kernel development naturally belongs there.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

* fixed mistypes
* added internal cross-references for sections
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This patch groups together section pertaining to the perf tools.  That way
everything is at the same place rather than spread out.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Adding a section that document how to use the Coresight framework and
drivers from the perf tools.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Field "owner" of struct coresight_desc has been removed a while back but
the documentation was not updated to reflect the changes.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add a description that the kernel headers should be used as far as it is
possible and then the system headers.
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Some lines used spaces instead of tabs at line start.
This can cause mangled lines in editors due to inconsistency.

Replace spaces for tabs where appropriate.
Signed-off-by: Thymo van Beers <thymovanbeers@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Thomas said:

There are a few bogus SPDX identifiers in various files and SPDX
Identifiers used in tree or about to be used which have no corresponding
License Text file in the LICENSES directory or use the new variant of the
GPL-2.0[+] license identifiers which are not mentioned in the GPL-2.0
Valid-License-Identifiers: tags.

There is no tool which can be used to scan the tree and also nothing which
helps people who submit patches to check their stuff before submission.

The following series cleans that up:

 - Add GPL-2.0-only and GPL-2.0-or-later identifiers to the GPL2.0 license
   and the Linux-syscall-note exception

 - Add X11, Apache-2.0, CC-BY-SA-4.0, CCDL-1.0, Linux-OpenIB license texts
   to the LICENSES directory along with the required documentation texts

 - Add a checker script which can read a single file or even a patch from
   the command line or does a full git tree scan

[Thomas also wins some sort of special prize for including an SPDX-checking
patch that complains about itself!]

The SPDX-License-Identifiers are growing in the kernel and so grow
expression failures and license IDs are used which have no corresponding
license text file in the LICENSES directory.

Add a script which gathers information from the LICENSES directory,
i.e. the various tags in the licenses and exception files and then scans
either input from stdin, which it treats as a single file or if started
without arguments it scans the full kernel tree.

It checks whether the license expression syntax is correct and also
validates whether the license identifiers used in the expressions are
available in the LICENSES files.

scripts/spdxcheck.py -h
usage: spdxcheck.py [-h] [-m MAXLINES] [-v] [path [path ...]]

SPDX expression checker

positional arguments:
  path                  Check path or file. If not given full git tree scan.
                        For stdin use "-"

optional arguments:
  -h, --help            show this help message and exit
  -m MAXLINES, --maxlines MAXLINES
                        Maximum number of lines to scan in a file. Default 15
  -v, --verbose         Verbose statistics output

include/dt-bindings/reset/amlogic,meson-axg-reset.h: 9:41 Invalid License ID: BSD

drivers/pinctrl/sh-pfc/pfc-r8a77965.c: 1:28 Invalid License ID: GPL-2.
include/dt-bindings/reset/amlogic,meson-axg-reset.h: 9:41 Invalid License ID: BSD

arch/x86/kernel/jailhouse.c: 1:28 Invalid License ID: GPL2.0
include/dt-bindings/reset/amlogic,meson-axg-reset.h: 9:41 Invalid License ID: BSD

arch/arm/mach-s3c24xx/h1940-bluetooth.c: 1:28 Invalid License ID: GPL-1.0
arch/x86/kernel/jailhouse.c: 1:28 Invalid License ID: GPL2.0
drivers/pinctrl/sh-pfc/pfc-r8a77965.c: 1:28 Invalid License ID: GPL-2.
include/dt-bindings/reset/amlogic,meson-axg-reset.h: 9:41 Invalid License ID: BSD
arch/x86/include/asm/jailhouse_para.h: 1:28 Invalid License ID: GPL2.0

arch/arm/mach-s3c24xx/h1940-bluetooth.c: 1:28 Invalid License ID: GPL-1.0
arch/x86/kernel/jailhouse.c: 1:28 Invalid License ID: GPL2.0
drivers/pinctrl/sh-pfc/pfc-r8a77965.c: 1:28 Invalid License ID: GPL-2.
include/dt-bindings/reset/amlogic,meson-axg-reset.h: 9:41 Invalid License ID: BSD
arch/x86/include/asm/jailhouse_para.h: 1:28 Invalid License ID: GPL2.0

License files:               14
Exception files:              1
License IDs                  19
Exception IDs                 1

Files checked:            61332
Lines checked:           669181
Files with SPDX:          16169
Files with errors:            5

real	0m2.642s
user	0m2.231s
sys	0m0.467s

That's a full tree sweep on my laptop. Note, this runs single threaded.

It scans by default the first 15 lines for a SPDX identifier where the
current max inside a top comment is at line 10. But that's going to be
faster once the identifiers are all in the first two lines as documented.

The python wizards will surely know how to do that smarter and faster, but
its at least better than no tool at all.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[jc: Fixed ironically erroneous SPDX tag and did chmod +x ]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The infiniband code uses a variant of the OpenIB license. This license is
BSD-2-Clause with the MIT disclaimer. The linux kernel uses this license
extensively throughout the driver subsystem since 2005. Note that the
OpenIB.org license is a true match to BSD-2-Clause.

The license text was copied from:

    https://spdx.org/licenses/Linux-OpenIB.html#licenseTextSigned-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add the full text of the CC-BY-SA-4.0 license to the kernel tree.  It was
copied directly from:

   https://spdx.org/licenses/CC-BY-SA-4.0.html#licenseTextSigned-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add the full text of the CDDL-1.0 to the kernel tree.  It was copied directly
from:

   https://spdx.org/licenses/CDDL-1.0.html#licenseTextSigned-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add the full text of the Apache License version 2 to the kernel tree.  It
was copied directly from:

   https://spdx.org/licenses/Apache-2.0.html#licenseTextSigned-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add the full text of the X11 to the kernel tree.  It was copied directly
from:

   https://spdx.org/licenses/X11.html#licenseTextSigned-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Quite some files have been flagged with the new GPL-2.0-only and
GPL-2.0-or-later identifiers which replace the original GPL-2.0 and
GPL-2.0+ identifiers in the SPDX license identifier specification, but the
identifiers are not mentioned as valid in the GPL-2.0 license file.

Add them to the license file and to the Linux-syscall-note exception to
make everything consistent again.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This patch corrects some spelling typo in ftrace-users.rst
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>