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 ac1f591249 ("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>
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>
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>
When EVM is enabled it forbids modification of metadata protected by
EVM unless there is already a valid EVM signature. If any modification
is made, the kernel will then generate a new EVM HMAC. However, this
does not map well on use cases which use only asymmetric EVM signatures,
as in this scenario the kernel is unable to generate new signatures.
This patch extends the /sys/kernel/security/evm interface to allow
userland to request that modification of these xattrs be permitted. This
is only permitted if no keys have already been loaded. In this
configuration, modifying the metadata will invalidate the EVM appraisal
on the file in question. This allows packaging systems to write out new
files, set the relevant extended attributes and then move them into
place.
There's also some refactoring of the use of evm_initialized in order to
avoid heading down codepaths that assume there's a key available.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The purpose of torture_runnable is to allow rcutorture and locktorture
to be started and stopped via sysfs when they are built into the kernel
(as in not compiled as loadable modules). However, the 0444 permissions
for both instances of torture_runnable prevent this use case from ever
being put into practice. Given that there have been no complaints
about this deficiency, it is reasonable to conclude that no one actually
makes use of this sysfs capability. The perf_runnable module parameter
for rcuperf is in the same situation.
This commit therefore removes both torture_runnable instances as well
as perf_runnable.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The GPIO polarity passed to phy-reset-gpio is ignored by the FEC
driver and it is assumed to be active low.
It can be active high only when the 'phy-reset-active-high' property
is present.
The current examples pass active high polarity and work fine, but
in order to improve the documentation make it explicit what the real
polarity is.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some platforms (e.g. TI's DRA7 USB2 instance) have more trouble
with the metastability workaround as it supports only
a High-Speed PHY and the PHY can enter into an Erratic state [1]
when the controller is set in SuperSpeed mode as part of
the metastability workaround.
This causes upto 2 seconds delay in enumeration on DRA7's USB2
instance in gadget mode.
If these platforms can be better off without the workaround,
provide a device tree property to suggest that so the workaround
is avoided.
[1] Device mode enumeration trace showing PHY Erratic Error.
irq/90-dwc3-969 [000] d... 52.323145: dwc3_event: event (00000901): Erratic Error [U0]
irq/90-dwc3-969 [000] d... 52.560646: dwc3_event: event (00000901): Erratic Error [U0]
irq/90-dwc3-969 [000] d... 52.798144: dwc3_event: event (00000901): Erratic Error [U0]
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Overlayfs is following redirects even when redirects are disabled. If this
is unintentional (probably the majority of cases) then this can be a
problem. E.g. upper layer comes from untrusted USB drive, and attacker
crafts a redirect to enable read access to otherwise unreadable
directories.
If "redirect_dir=off", then turn off following as well as creation of
redirects. If "redirect_dir=follow", then turn on following, but turn off
creation of redirects (which is what "redirect_dir=off" does now).
This is a backward incompatible change, so make it dependent on a config
option.
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
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
...
Pull media fixes from Mauro Carvalho Chehab:
"A series of fixes for the media subsytem:
- The largest amount of fixes in this series is with regards to
comments that aren't kernel-doc, but start with "/**".
A new check added for 4.15 makes it to produce a *huge* amount of
new warnings (I'm compiling here with W=1). Most of the patches in
this series fix those.
No code changes - just comment changes at the source files
- rc: some fixed in order to better handle RC repetition codes
- v4l-async: use the v4l2_dev from the root notifier when matching
sub-devices
- v4l2-fwnode: Check subdev count after checking port
- ov 13858 and et8ek8: compilation fix with randconfigs
- usbtv: a trivial new USB ID addition
- dibusb-common: don't do DMA on stack on firmware load
- imx274: Fix error handling, add MAINTAINERS entry
- sir_ir: detect presence of port"
* tag 'media/v4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (50 commits)
media: imx274: Fix error handling, add MAINTAINERS entry
media: v4l: async: use the v4l2_dev from the root notifier when matching sub-devices
media: v4l2-fwnode: Check subdev count after checking port
media: et8ek8: select V4L2_FWNODE
media: ov13858: Select V4L2_FWNODE
media: rc: partial revert of "media: rc: per-protocol repeat period"
media: dvb: i2c transfers over usb cannot be done from stack
media: dvb-frontends: complete kernel-doc markups
media: docs: add documentation for frontend attach info
media: dvb_frontends: fix kernel-doc macros
media: drivers: remove "/**" from non-kernel-doc comments
media: lm3560: add a missing kernel-doc parameter
media: rcar_jpu: fix two kernel-doc markups
media: vsp1: add a missing kernel-doc parameter
media: soc_camera: fix a kernel-doc markup
media: mt2063: fix some kernel-doc warnings
media: radio-wl1273: fix a parameter name at kernel-doc macro
media: s3c-camif: add missing description at s3c_camif_find_format()
media: mtk-vpu: add description for wdt fields at struct mtk_vpu
media: vdec: fix some kernel-doc warnings
...
Pull DeviceTree fixes from Rob Herring:
"Another set of DT fixes:
- Fixes from overlay code rework. A trifecta of fixes to the locking,
an out of bounds access, and a memory leak in of_overlay_apply()
- Clean-up at25 eeprom binding document
- Remove leading '0x' in unit-addresses from binding docs"
* tag 'devicetree-fixes-for-4.15-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
of: overlay: Make node skipping in init_overlay_changeset() clearer
of: overlay: Fix out-of-bounds write in init_overlay_changeset()
of: overlay: Fix (un)locking in of_overlay_apply()
of: overlay: Fix memory leak in of_overlay_apply() error path
dt-bindings: eeprom: at25: Document device-specific compatible values
dt-bindings: eeprom: at25: Grammar s/are can/can/
dt-bindings: Remove leading 0x from bindings notation
of: overlay: Remove else after goto
of: Spelling s/changset/changeset/
of: unittest: Remove bogus overlay mutex release from overlay_data_add()
Chris requested this backmerge for a reconciliation on
drm_print.h between drm-misc-next and drm-intel-next-queued
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
This adds basic support for BQ27521 battery monitor, used in Nokia N9
and N950. In particular, battery voltage is important to be able to
tell when the battery is almost empty. Emptying battery on N950 is
pretty painful, as flasher needs to be used to recover phone in such case.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Andrew F. Davis <afd@ti.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
The xHCI driver currently has the IMOD set to 160, which
translates to an IMOD interval of 40,000ns (160 * 250)ns
Commit 0cbd4b34cd ("xhci: mediatek: support MTK xHCI host controller")
introduced a QUIRK for the MTK platform to adjust this interval to 20,
which translates to an IMOD interval of 5,000ns (20 * 250)ns. This is
due to the fact that the MTK controller IMOD interval is 8 times
as much as defined in xHCI spec.
Instead of adding more quirk bits for additional platforms, this patch
introduces the ability for vendors to set the IMOD_INTERVAL as is
optimal for their platform. By using device_property_read_u32() on
"imod-interval-ns", the IMOD INTERVAL can be specified in nano seconds.
If no interval is specified, the default of 40,000ns (IMOD=160) will be
used.
No bounds checking has been implemented due to the fact that a vendor
may have violated the spec and would need to specify a value outside of
the max 8,000 IRQs/second limit specified in the xHCI spec.
Tested-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xHCI compatible USB host controllers(i.e. super-speed USB3 controllers)
can be implemented with the Debug Capability(DbC). It presents a debug
device which is fully compliant with the USB framework and provides the
equivalent of a very high performance full-duplex serial link. The debug
capability operation model and registers interface are defined in 7.6.8
of the xHCI specification, revision 1.1.
The DbC debug device shares a root port with the xHCI host. By default,
the debug capability is disabled and the root port is assigned to xHCI.
When the DbC is enabled, the root port will be assigned to the DbC debug
device, and the xHCI sees nothing on this port. This implementation uses
a sysfs node named <dbc> under the xHCI device to manage the enabling
and disabling of the debug capability.
When the debug capability is enabled, it will present a debug device
through the debug port. This debug device is fully compliant with the
USB3 framework, and it can be enumerated by a debug host on the other
end of the USB link. As soon as the debug device is configured, a TTY
serial device named /dev/ttyDBC0 will be created.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2017-12-07
The following pull-request contains BPF updates for your net-next tree.
The main changes are:
1) Detailed documentation of BPF development process from Daniel.
2) Addition of is_fullsock, snd_cwnd and srtt_us fields to bpf_sock_ops
from Lawrence.
3) Minor follow up for bpf_skb_set_tunnel_key() from William.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The w1 master driver includes a complete open drain emulation
reimplementation among other things.
This converts the driver and all board files using it to use
GPIO descriptors associated with the device to look up the
GPIO wire, as well ass the optional pull-up GPIO line.
When probed from the device tree, the driver will just pick
descriptors and use them right off. For the two board files
in the kernel, we add descriptor lookups so we do not need
to keep any old platform data handling around for the GPIO
lines.
As the platform data is also a state container for this driver,
we augment it to contain the GPIO descriptors.
w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone
since this pair was a reimplementation of open drain emulation
which is now handled by gpiolib.
The special "linux,open-drain" flag is a bit of mishap here:
it has the same semantic as the same flags in I2C: it means
that something in the platform is setting up the line as
open drain behind our back. We handle this the same way as
in I2C.
To drive the pull-up, we need to bypass open drain emulation
in gpiolib for the line, and this is done by driving it high
using gpiod_set_raw_value() which has been augmented to have
the semantic of overriding the open drain emulation.
We also augment the documentation to reflect the way to pass
GPIO descriptors from the machine.
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
UAPI Changes:
- Add "panel orientation" property to DRM to indicate orientation of the
panel vs the device's casing (Hans de Goede)
Core Changes:
- misc doc and bug fixes
Driver Changes:
- sun4i: Many improvements to the DE driver like multi-plane support and
YUV formats (Jernej Skrabec)
* tag 'drm-misc-next-2017-12-07' of git://anongit.freedesktop.org/drm/drm-misc: (50 commits)
drm/sun4i: Fix uninitialized variables in vi layer
drm/fb-helper: Fix potential NULL pointer dereference
gpu: drm: stm: Adopt SPDX identifiers
gpu: drm: sti: Adopt SPDX identifiers
drm/fsl-dcu: Use drm_mode_config_helper_suspend/resume()
drm/sun4i: Wire in DE2 YUV support
drm/sun4i: Expand DE2 scaler lib with YUV support
drm/sun4i: Add DE2 definitions for YUV formats
drm/sun4i: Add DE2 CSC library
drm/sun4i: Add CCSC property to DE2 configuration
drm/sun4i: Add support for HW scaling to DE2
drm/sun4i: Add scaler configuration to DE2 mixers
drm/sun4i: Add support for DE2 VI planes
drm/sun4i: Reorganize UI layer code in DE2
drm/sun4i: Add support for all HW supported DE2 RGB formats
drm/sun4i: Add multi plane support to DE2 driver
drm/sun4i: Move interlace related code in DE2
drm/sun4i: Move channel size related code in DE2
drm/sun4i: Move line width setting in DE2
drm/sun4i: Use values calculated by atomic check
...
of_cpufreq_cooling_register() isn't used by anyone and so can be
removed, but then we would be left with two routines:
cpufreq_cooling_register() and of_cpufreq_power_cooling_register() that
would look odd.
Remove current implementation of of_cpufreq_cooling_register() and
rename of_cpufreq_power_cooling_register() as
of_cpufreq_cooling_register(). This simplifies lots of stuff.
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
All the callers of of_cpufreq_power_cooling_register() have almost
identical code and it makes more sense to move that code into the helper
as its all about reading DT properties.
This got rid of lot of redundant code.
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add documentation describing how device tree can be used to configure
wireless chips supported by the mt76 driver.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
If a task sleeps in a set of patched functions uninterruptedly, it could
block the whole transition indefinitely. Thus it may be useful to clear
its TIF_PATCH_PENDING to allow the process to finish.
Admin can do that now by writing to force sysfs attribute in livepatch
sysfs directory. TIF_PATCH_PENDING is then cleared for all tasks and the
transition can finish successfully.
Important note! Administrator should not use this feature without a
clearance from a patch distributor. It must be checked that by doing so
the consistency model guarantees are not violated. Removal (rmmod) of
patch modules is permanently disabled when the feature is used. It
cannot be guaranteed there is no task sleeping in such module.
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The AXP813 has only two GPIOs. GPIO0 can either be used as a GPIO, an
LDO regulator or an ADC. GPIO1 can be used either as a GPIO or an LDO
regulator.
Moreover, the status bit of the GPIOs when in input mode is not offset
by 4 unlike the AXP209.
Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
