Add documentation about typedefs for function prototypes and
move it to happen earlier.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

There is a mess on this chapter: it suggests that even
enums and unions should be documented with "struct". That's
not the way it should be ;-)

Fix it and move it to happen earlier.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Move its contents to happen earlier and improve the description
of return values, adding a subsection to it. Most of the contents
there came from kernel-doc-nano-HOWTO.txt.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The private members section can now be moved to be together
with the arguments section. Move it there and add an example
about the usage of public:
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add a new section to describe kernel-doc arguments,
adding examples about how identation should happen, as failing
to do that causes Sphinx to do the wrong thing.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

add missing indent whitespace to list item, fixes the warning:

- process/submit-checklist.rst:41: WARNING: Enumerated list ends without a blank
  line; unexpected unindent.
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
Reviewed-by: Darren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

ftrace-uses.rst is not yet included into any toctree, but since it is
a .rst file, it is parsed by the Sphinx build. Thats, why we see some
WARNINGS:

- trace/ftrace-uses.rst:53: WARNING: Definition list ends without a blank line; unexpected unindent.
- trace/ftrace-uses.rst:89: WARNING: Inline emphasis start-string without end-string.
- trace/ftrace-uses.rst:89: WARNING: Inline emphasis start-string without end-strin

Fixing the code-block directives results in a less noisy build, but the 'not
included' WARNING will be stay:

- trace/ftrace-uses.rst: WARNING: document isn't included in any toctree
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

A reference to printk-formats.txt didn't get updated when the file moved;
fix that.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

`Documentation/i2c/dev-interface` gives examples for accessing i2c from
userspace.

There's a note that warns developers about the two `i2c-dev.h` header
files which were shipped with the kernel and i2c-tools separately.

However, following i2c-tools commits suggest that the header files are now
identical (in functionality) and `i2c_*` helper functions are now defined
in a separate header called `i2c/smbus.h`, which is distributed with
i2c-tools:

commit 652619121974 ("Minimize differences with kernel flavor")
commit 93caf007f4cb ("Move SMBus helper functions to include/i2c/smbus.h")

Thus, I've converted the warning paragraph into a historical note and
updated the suggested header files.
Signed-off-by: Cengiz Can <cengizc@gmail.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Update Documentation/driver-api/usb/usb3-debug-port.rst. This update
includes the guide for using xHCI debug capability based TTY serial
link.

Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add my name to the list.
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add my name to the list.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Onewire devices has 6 byte long unique serial numbers, 1 byte family
code and 1 byte CRC. Linux sysfs presents the device folder in the
form of familyID-deviceID, so CRC is not shown. The consequence is
that the device serial number is always a 12 long hex-string, but
doc says 13 in one place. This is corrected by this change.
Reference: https://en.wikipedia.org/wiki/1-WireSigned-off-by: Gergo Huszty <huszty.gergo@digitaltrip.hu>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

All non-historic operating systems support the full range of Unicode here,
thus you can make filenames for example in Gothic (𐌼𐌴𐍉𐍅), the other Gothic
(𝓂ℯℴ𝓌) or the third Gothic (𝗆𝖾𝗈𝗐), or declare something as 💩.

Characters above U+FFFF are encoded on four bytes.
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Hashing addresses printed with printk specifier %p was implemented
recently. During development a number of issues were raised regarding
leaking kernel addresses to userspace. Other documentation was updated but
security/self-protection missed out.

Add self-protection documentation regarding printing kernel addresses.
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Recently the behaviour of printk specifier %pK was changed. The
documentation does not currently mirror this.

Update documentation for sysctl kptr_restrict.
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/printk-formats.txt is a candidate for conversion to
ReStructuredText format. Some effort has already been made to do this
conversion even thought the suffix is currently .txt

Changes required to complete conversion

 - Move printk-formats.txt to core-api/printk-formats.rst
 - Add entry to Documentation/core-api/index.rst
 - Remove entry from Documentation/00-INDEX
 - Fix minor grammatical errors.
 - Order heading adornments as suggested by rst docs.
 - Use 'Passed by reference' uniformly.
 - Update pointer documentation around %px specifier.
 - Fix erroneous double backticks (to commas).
 - Remove extraneous double backticks (suggested by Jonathan Corbet).
 - Simplify documentation for kobject.
Signed-off-by: Tobin C. Harding <me@tobin.cc>
[jc: downcased "kernel"]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This warning will happen for every normal kernel docs build and doesn't
carry any useful information.  Should anybody actually depend on this
"version" variable (which isn't clear to me), the "unknown version" value
will be clue enough.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add default value review to the submit checklist, referring to the
preference for "default n" from the previous patch added to
Documentation/kbuild/kconfig-language.txt.

Cc: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <mmarek@suse.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-kbuild@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Document the preference [1] for new CONFIG options to "default n" (or
not use default at all) in order to minimizes changes to the config,
especially to avoid "make oldconfig" growing unnecessarily from release
to release.

Document the exceptions where it is acceptable to use "default y/m" for
new CONFIG options.

1. https://lkml.org/lkml/2017/11/18/257

Cc: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <mmarek@suse.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-kbuild@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Update kernel-doc notation in lib/uuid.c and then add UUID/GUID
function interfaces to kernel-api.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
[jc: tweaked the uuid_is_valid() kerneldoc]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add sort() and list_sort() to the kernel API documentation in a
new "Sorting" section.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Commit ac1f5912 ("kernel/watchdog.c: add sysctl knob
hardlockup_panic") added the hardlockup_panic sysctl, but did not add it
to Documentation/sysctl/kernel.txt.  Add this, and reference it from the
corresponding entry in Documentation/admin-guide/kernel-parameters.txt.
Signed-off-by: Scott Wood <swood@redhat.com>
Acked-by: Christoph von Recklinghausen <crecklin@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Fix the spelling of 'enumerate' in this document.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

...just enough to say what the purpose is and to solicit more
contributions.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

There is currently very little documentation in the kernel on maintainer
level tasks. In particular there are no documents on creating pull
requests to submit to Linus.

Quoting Greg Kroah-Hartman on LKML:

    Anyway, this actually came up at the kernel summit / maintainer
    meeting a few weeks ago, in that "how do I make a
    good pull request to Linus" is something we need to document.

    Here's what I do, and it seems to work well, so maybe we should turn
    it into the start of the documentation for how to do it.

(quote references: kernel summit, Europe 2017)

Create a new kernel documentation book 'how to be a maintainer'
(suggested by Jonathan Corbet). Add chapters on 'configuring git' and
'creating a pull request'.

Most of the content was written by Linus Torvalds and Greg Kroah-Hartman
in discussion on LKML. This is stated at the start of one of the
chapters and the original email thread is referenced in
'pull-requests.rst'.
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Some functions from refcount_t API provide different
memory ordering guarantees that their atomic counterparts.
This adds a document outlining these differences (
Documentation/core-api/refcount-vs-atomic.rst) as well as
some other minor improvements.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This link is dead:

    $ curl -vI http://usb.cs.tum.edu/usbdoc
    * Could not resolve host: usb.cs.tum.edu
    * Closing connection 0
    curl: (6) Could not resolve host: usb.cs.tum.edu

I found the document somewhere else. Let's replace it.
Signed-off-by: Stefan Tatschner <stefan.tatschner@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

On media, we now have an struct declared with:

struct lirc_fh {
        struct list_head list;
        struct rc_dev *rc;
        int                             carrier_low;
        bool                            send_timeout_reports;
        DECLARE_KFIFO_PTR(rawir, unsigned int);
        DECLARE_KFIFO_PTR(scancodes, struct lirc_scancode);
        wait_queue_head_t               wait_poll;
        u8                              send_mode;
        u8                              rec_mode;
};

gpiolib.c has a similar declaration with DECLARE_KFIFO().

Currently, those produce the following error:

	./include/media/rc-core.h:96: warning: No description found for parameter 'int'
	./include/media/rc-core.h:96: warning: No description found for parameter 'lirc_scancode'
	./include/media/rc-core.h:96: warning: Excess struct member 'rawir' description in 'lirc_fh'
	./include/media/rc-core.h:96: warning: Excess struct member 'scancodes' description in 'lirc_fh'
	../drivers/gpio/gpiolib.c:601: warning: No description found for parameter '16'
	../drivers/gpio/gpiolib.c:601: warning: Excess struct member 'events' description in 'lineevent_state'

So, teach kernel-doc how to parse DECLARE_KFIFO() and DECLARE_KFIFO_PTR().

While here, relax at the past DECLARE_foo() macros, accepting a random
number of spaces after comma.

The addition of DECLARE_KFIFO() was
Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Corrected a typo.
Signed-off-by: Marco Donato Torsello <marcodonato.torsello@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The URLs in mono.rst redirect to pages on www.mono-project.com, so let's
update them. I took the liberty to update the compilation instructions
to the Linux-specific version, because readers of the kernel
documentation will most likely use Linux.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

HPFS does not set SB_I_VERSION and does not use the i_version counter
internally.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Mikulas Patocka <mikulas@twibright.com>
Reviewed-by: Mikulas Patocka <mikulas@twibright.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sign_extend32 counts the sign bit parameter from 0, not from 1.  So we
have to use "11" for 12th bit, not "12".

This mistake means we have not allowed negative op and cmp args since
commit 30d6e0a4 ("futex: Remove duplicated code and fix undefined
behaviour") till now.

Fixes: 30d6e0a4 ("futex: Remove duplicated code and fix undefined behaviour")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull btrfs fixes from David Sterba:
 "This contains a few fixes (error handling, quota leak, FUA vs
  nobarrier mount option).

  There's one one worth mentioning separately - an off-by-one fix that
  leads to overwriting first byte of an adjacent page with 0, out of
  bounds of the memory allocated by an ioctl. This is under a privileged
  part of the ioctl, can be triggerd in some subvolume layouts"

* tag 'for-4.15-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: Fix possible off-by-one in btrfs_search_path_in_tree
  Btrfs: disable FUA if mounted with nobarrier
  btrfs: fix missing error return in btrfs_drop_snapshot
  btrfs: handle errors while updating refcounts in update_ref_for_cow
  btrfs: Fix quota reservation leak on preallocated files

Pull ARM SoC fixes from Olof Johansson:

 - A revert of all SCPI changes from the 4.15 merge window. They had
   regressions on the Amlogic platforms, and the submaintainer isn't
   around to fix these bugs due to vacation, etc. So we agreed to revert
   and revisit in next release cycle.

 - A series fixing a number of bugs for ARM CCN interconnect, around
   module unload, smp_processor_id() in preemptable context, and fixing
   some memory allocation failure checks.

 - A handful of devicetree fixes for different platforms, fixing
   warnings and errors that were previously ignored by the compiler.

 - The usual set of mostly minor fixes for different platforms.

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (42 commits)
  ARM64: dts: meson-gx: fix UART pclk clock name
  ARM: omap2: hide omap3_save_secure_ram on non-OMAP3 builds
  arm: dts: nspire: Add missing #phy-cells to usb-nop-xceiv
  ARM: dts: Fix dm814x missing phy-cells property
  ARM: dts: Fix elm interrupt compiler warning
  bus: arm-ccn: fix module unloading Error: Removing state 147 which has instances left.
  bus: arm-cci: Fix use of smp_processor_id() in preemptible context
  bus: arm-ccn: Fix use of smp_processor_id() in preemptible context
  bus: arm-ccn: Simplify code
  bus: arm-ccn: Check memory allocation failure
  bus: arm-ccn: constify attribute_group structures.
  firmware: arm_scpi: Revert updates made during v4.15 merge window
  arm: dts: marvell: Add missing #phy-cells to usb-nop-xceiv
  arm64: dts: sort vendor subdirectories in Makefile alphabetically
  meson-gx-socinfo: Fix package id parsing
  ARM: meson: fix spelling mistake: "Couln't" -> "Couldn't"
  ARM: dts: meson: fix the memory region of the GPIO interrupt controller
  ARM: dts: meson: correct the sort order for the the gpio_intc node
  MAINTAINERS: exclude other Socionext SoC DT files from ARM/UNIPHIER entry
  arm64: dts: uniphier: remove unnecessary interrupt-parent
  ...

Pull KVM fixes from Radim Krčmář:
 "ARM:
   - A number of issues in the vgic discovered using SMATCH
   - A bit one-off calculation in out stage base address mask (32-bit
     and 64-bit)
   - Fixes to single-step debugging instructions that trap for other
     reasons such as MMMIO aborts
   - Printing unavailable hyp mode as error
   - Potential spinlock deadlock in the vgic
   - Avoid calling vgic vcpu free more than once
   - Broken bit calculation for big endian systems

 s390:
   - SPDX tags
   - Fence storage key accesses from problem state
   - Make sure that irq_state.flags is not used in the future

  x86:
   - Intercept port 0x80 accesses to prevent host instability (CVE)
   - Use userspace FPU context for guest FPU (mainly an optimization
     that fixes a double use of kernel FPU)
   - Do not leak one page per module load
   - Flush APIC page address cache from MMU invalidation notifiers"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (28 commits)
  KVM: x86: fix APIC page invalidation
  KVM: s390: Fix skey emulation permission check
  KVM: s390: mark irq_state.flags as non-usable
  KVM: s390: Remove redundant license text
  KVM: s390: add SPDX identifiers to the remaining files
  KVM: VMX: fix page leak in hardware_setup()
  KVM: VMX: remove I/O port 0x80 bypass on Intel hosts
  x86,kvm: remove KVM emulator get_fpu / put_fpu
  x86,kvm: move qemu/guest FPU switching out to vcpu_run
  KVM: arm/arm64: Fix broken GICH_ELRSR big endian conversion
  KVM: arm/arm64: kvm_arch_destroy_vm cleanups
  KVM: arm/arm64: Fix spinlock acquisition in vgic_set_owner
  kvm: arm: don't treat unavailable HYP mode as an error
  KVM: arm/arm64: Avoid attempting to load timer vgic state without a vgic
  kvm: arm64: handle single-step of hyp emulated mmio instructions
  kvm: arm64: handle single-step during SError exceptions
  kvm: arm64: handle single-step of userspace mmio instructions
  kvm: arm64: handle single-stepping trapped instructions
  KVM: arm/arm64: debug: Introduce helper for single-step
  arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one
  ...

* fixes:
  ARM64: dts: meson-gx: fix UART pclk clock name
  ARM: dts: Fix dm814x missing phy-cells property
  ARM: dts: Fix elm interrupt compiler warning
  bus: arm-ccn: fix module unloading Error: Removing state 147 which has instances left.
  bus: arm-cci: Fix use of smp_processor_id() in preemptible context
  bus: arm-ccn: Fix use of smp_processor_id() in preemptible context
  bus: arm-ccn: Simplify code
  bus: arm-ccn: Check memory allocation failure
  bus: arm-ccn: constify attribute_group structures.
  meson-gx-socinfo: Fix package id parsing
  ARM: meson: fix spelling mistake: "Couln't" -> "Couldn't"
  ARM: dts: meson: fix the memory region of the GPIO interrupt controller
  ARM: dts: meson: correct the sort order for the the gpio_intc node

Merge tag 'amlogic-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-amlogic into fixes

Amlogic fixes for v4.15-rc
- GPIO interrupt fixes
- socinfo fix for GX series
- fix typo

* tag 'amlogic-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-amlogic:
  ARM64: dts: meson-gx: fix UART pclk clock name
  meson-gx-socinfo: Fix package id parsing
  ARM: meson: fix spelling mistake: "Couln't" -> "Couldn't"
  ARM: dts: meson: fix the memory region of the GPIO interrupt controller
  ARM: dts: meson: correct the sort order for the the gpio_intc node
Signed-off-by: Olof Johansson <olof@lixom.net>