Tyler Hicks pointed me at an additional article on RCU and I figured
it should probably be mentioned with the others.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
An IRC discussion uncovered many conflicting opinions on what types
of data may be atomically loaded and stored. This commit therefore
calls this out the official set: pointers, longs, ints, and chars (but
not shorts). This commit also gives some examples of compiler mischief
that can thwart atomicity.
Please note that this discussion is relevant to !SMP kernels if
CONFIG_PREEMPT=y: preemption can cause almost as much trouble as can SMP.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Chris Zankel <chris@zankel.net>
Running CPU-hotplug operations concurrently with rcutorture has
historically been a good way to find bugs in both RCU and CPU hotplug.
This commit therefore adds an rcutorture module parameter called
"onoff_interval" that causes a randomly selected CPU-hotplug operation to
be executed at the specified interval, in seconds. The default value of
"onoff_interval" is zero, which disables rcutorture-instigated CPU-hotplug
operations.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Although it is easy to run rcutorture tests under KVM, there is currently
no nice way to run such a test for a fixed time period, collect all of
the rcutorture data, and then shut the system down cleanly. This commit
therefore adds an rcutorture module parameter named "shutdown_secs" that
specified the run duration in seconds, after which rcutorture terminates
the test and powers the system down. The default value for "shutdown_secs"
is zero, which disables shutdown.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Update various files in Documentation/RCU to reflect srcu_read_lock_raw()
and srcu_read_unlock_raw(). Credit to Peter Zijlstra for suggesting
use of the existing _raw suffix instead of the earlier bulkref names.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
One of lclaudio's systems was seeing RCU CPU stall warnings from idle.
These turned out to be caused by a bug that stopped scheduling-clock
tick interrupts from being sent to a given CPU for several hundred seconds.
This commit therefore updates the documentation to call this out as a
possible cause for RCU CPU stall warnings.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Earlier versions of RCU used the scheduling-clock tick to detect idleness
by checking for the idle task, but handled idleness differently for
CONFIG_NO_HZ=y. But there are now a number of uses of RCU read-side
critical sections in the idle task, for example, for tracing. A more
fine-grained detection of idleness is therefore required.
This commit presses the old dyntick-idle code into full-time service,
so that rcu_idle_enter(), previously known as rcu_enter_nohz(), is
always invoked at the beginning of an idle loop iteration. Similarly,
rcu_idle_exit(), previously known as rcu_exit_nohz(), is always invoked
at the end of an idle-loop iteration. This allows the idle task to
use RCU everywhere except between consecutive rcu_idle_enter() and
rcu_idle_exit() calls, in turn allowing architecture maintainers to
specify exactly where in the idle loop that RCU may be used.
Because some of the userspace upcall uses can result in what looks
to RCU like half of an interrupt, it is not possible to expect that
the irq_enter() and irq_exit() hooks will give exact counts. This
patch therefore expands the ->dynticks_nesting counter to 64 bits
and uses two separate bitfields to count process/idle transitions
and interrupt entry/exit transitions. It is presumed that userspace
upcalls do not happen in the idle loop or from usermode execution
(though usermode might do a system call that results in an upcall).
The counter is hard-reset on each process/idle transition, which
avoids the interrupt entry/exit error from accumulating. Overflow
is avoided by the 64-bitness of the ->dyntick_nesting counter.
This commit also adds warnings if a non-idle task asks RCU to enter
idle state (and these checks will need some adjustment before applying
Frederic's OS-jitter patches (http://lkml.org/lkml/2011/10/7/246).
In addition, validation of ->dynticks and ->dynticks_nesting is added.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
There are a number of bugs that can leak or overuse lock classes,
which can cause the maximum number of lock classes (currently 8191)
to be exceeded. However, the documentation does not tell you how to
track down these problems. This commit addresses this shortcoming.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This removes comment tags intended for emacs configuration from
67 files in the Media API DocBook. Such comments are not really
helpful and violate the coding style rules.
Signed-off-by: Sylwester Nawrocki <snjw23@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This resolves the conflict in the
drivers/staging/iio/industrialio-core.c file due to two different
changes made to resolve the same problem.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This lets us handle the PS3 merge easier, as well as syncing up with
other USB fixes already in the -rc4 tree.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Several snapshot ioctls were marked for removal quite some time ago,
since they were deprecated. Remove them.
Suggested-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda/realtek - Fix lost speaker volume controls
ALSA: hda/realtek - Create "Bass Speaker" for two speaker pins
ALSA: hda/realtek - Don't create extra controls with channel suffix
ALSA: hda - Fix remaining VREF mute-LED NID check in post-3.1 changes
ALSA: hda - Fix GPIO LED setup for IDT 92HD75 codecs
ASoC: Provide a more complete DMA driver stub
ASoC: Remove references to corgi and spitz from machine driver document
ASoC: Make SND_SOC_MX27VIS_AIC32X4 depend on I2C
ASoC: Fix dependency for SND_SOC_RAUMFELD and SND_PXA2XX_SOC_HX4700
ASoC: uda1380: Return proper error in uda1380_modinit failure path
ASoC: kirkwood: Make SND_KIRKWOOD_SOC_OPENRD and SND_KIRKWOOD_SOC_T5325 depend on I2C
ASoC: Mark WM8994 ADC muxes as virtual
ALSA: hda/realtek - Fix Oops in alc_mux_select()
ALSA: sis7019 - give slow codecs more time to reset
Update the documentation to explain the perils of directly using
mutex_[un]lock(&pm_mutex) and recommend the usage of the safe
APIs [un]lock_system_sleep() instead.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
For now they are a minimal binding. It needs to be amended with
vendor-specific settings for phy setup and link tuning, etc.
v2: Added bindings specification and phy_type properties
Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Stephen Warren <swarren@nvidia.com>
This code has been on the list to remove for a long
time, so disable it by default, add a warning to its
Kconfig, and schedule it for removal in 3.5.
The only known dependency, hal, has not required it
since its 0.5.12 release, which was in early 2009
and hal has since been deprecated completely.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This doesn't interact with resizing well, since it doesn't set the
size of the device to the size at the snapshot. It's also an expensive
operation to be synchronous. Rollback can still be done with the
userspace rbd tool.
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.com>
With this patch the OProfile Basic Mode Sampling support for System z
is enhanced with a counter file system. That way hardware sampling
can be configured using the user space tools with only little
modifications.
With the patch by default new cpu_types (s390/z10, s390/z196) are
returned in order to indicate that we are running a CPU which provides
the hardware sampling facility. Existing user space tools will
complain about an unknown cpu type. In order to be compatible with
existing user space tools the `cpu_type' module parameter has been
added. Setting the parameter to `timer' will force the module to
return `timer' as cpu_type. The module will still try to use hardware
sampling if available and the hwsampling virtual filesystem will be
also be available for configuration. So this has a different effect
than using the generic oprofile module parameter `timer=1'.
If the basic mode sampling is enabled on the machine and the
cpu_type=timer parameter is not used the kernel module will provide
the following virtual filesystem:
/dev/oprofile/0/enabled
/dev/oprofile/0/event
/dev/oprofile/0/count
/dev/oprofile/0/unit_mask
/dev/oprofile/0/kernel
/dev/oprofile/0/user
In the counter file system only the values of 'enabled', 'count',
'kernel', and 'user' are evaluated by the kernel module. Everything
else must contain fixed values.
The 'event' value only supports a single event - HWSAMPLING with value
0.
The 'count' value specifies the hardware sampling rate as it is passed
to the CPU measurement facility.
The 'kernel' and 'user' flags can now be used to filter for samples
when using hardware sampling.
Additionally also the following file will be created:
/dev/oprofile/timer/enabled
This will always be the inverted value of /dev/oprofile/0/enabled. 0
is not accepted without hardware sampling.
Signed-off-by: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
net: Silence seq_scale() unused warning
ipv4:correct description for tcp_max_syn_backlog
pasemi_mac: Fix building as module
netback: Fix alert message.
r8169: fix Rx index race between FIFO overflow recovery and NAPI handler.
r8169: Rx FIFO overflow fixes.
ipv4: Fix peer validation on cached lookup.
ipv4: make sure RTO_ONLINK is saved in routing cache
iwlwifi: change the default behavior of watchdog timer
iwlwifi: do not re-configure HT40 after associated
iwlagn: fix HW crypto for TX-only keys
Revert "mac80211: clear sta.drv_priv on reconfiguration"
mac80211: fill rate filter for internal scan requests
cfg80211: amend regulatory NULL dereference fix
cfg80211: fix race on init and driver registration
Since commit c5ed63d66f24(tcp: fix three tcp sysctls tuning),
sysctl_max_syn_backlog is determined by tcp_hashinfo->ehash_mask,
and the minimal value is 128, and it will increase in proportion to the
memory of machine.
The original description for tcp_max_syn_backlog and sysctl_max_syn_backlog
are out of date.
Changelog:
V2: update description for sysctl_max_syn_backlog
Signed-off-by: Weiping Pan <panweiping3@gmail.com>
Reviewed-by: Shan Wei <shanwei88@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Document the device tree binding for the WM8903 codec, and modify the
driver to extract platform data from the device tree, if present.
Based on work by John Bonesio, but significantly reworked since then.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This patch adds support for Roccat Isku keyboard.
Userland tools can be found at http://sourceforge.net/projects/roccat
Signed-off-by: Stefan Achatz <erazor_de@users.sourceforge.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This patch adds a per-pci-device subdirectory in sysfs called:
/sys/bus/pci/devices/<device>/msi_irqs
This sub-directory exports the set of msi vectors allocated by a given
pci device, by creating a numbered sub-directory for each vector beneath
msi_irqs. For each vector various attributes can be exported.
Currently the only attribute is called mode, which tracks the
operational mode of that vector (msi vs. msix)
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Commit dfb09f9b7a ("x86, amd: Avoid cache aliasing penalties
on AMD family 15h") introduced a kernel command line parameter
called 'align_va_addr' which still refers to arguments used in
an earlier version of the patch and which got changed without
updating the documentation. Correct that omission.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Frank Arnold <frank.arnold@amd.com>
Link: http://lkml.kernel.org/r/1321873819-29541-1-git-send-email-bp@amd64.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The commit 2c043bcbf2 ("regulator: pass additional of_node to
regulator_register()") added an additional parameter to the
regulator_register() API.
Update the Documentation accordingly to reflect the change
in the function signature.
Reported-by: Thomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This essentially reverts:
2b666859ec: x86: Default to vsyscall=native for now
The ABI breakage should now be fixed by:
commit 48c4206f5b02f28c4c78a1f5b491d3772fb64fb9
Author: Andy Lutomirski <luto@mit.edu>
Date: Thu Oct 20 08:48:19 2011 -0700
x86-64: Set siginfo and context on vsyscall emulation faults
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/93154af3b2b6d208906ae02d80d92cf60c6fa94f.1320712291.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Currently, messages are just output on the detection of stack
overflow, which is not sufficient for systems that need a
high reliability. This is because in general the overflow may
corrupt data, and the additional corruption may occur due to
reading them unless systems stop.
This patch adds the sysctl parameter
kernel.panic_on_stackoverflow and causes a panic when detecting
the overflows of kernel, IRQ and exception stacks except user
stack according to the parameter. It is disabled by default.
Signed-off-by: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: yrl.pp-manager.tt@hitachi.com
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20111129060836.11076.12323.stgit@ltc219.sdl.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Open vSwitch is a multilayer Ethernet switch targeted at virtualized
environments. In addition to supporting a variety of features
expected in a traditional hardware switch, it enables fine-grained
programmatic extension and flow-based control of the network.
This control is useful in a wide variety of applications but is
particularly important in multi-server virtualization deployments,
which are often characterized by highly dynamic endpoints and the need
to maintain logical abstractions for multiple tenants.
The Open vSwitch datapath provides an in-kernel fast path for packet
forwarding. It is complemented by a userspace daemon, ovs-vswitchd,
which is able to accept configuration from a variety of sources and
translate it into packet processing rules.
See http://openvswitch.org for more information and userspace
utilities.
Signed-off-by: Jesse Gross <jesse@nicira.com>
* 'usb-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (21 commits)
usb: ftdi_sio: add PID for Propox ISPcable III
Revert "xHCI: reset-on-resume quirk for NEC uPD720200"
xHCI: fix bug in xhci_clear_command_ring()
usb: gadget: fsl_udc: fix dequeuing a request in progress
usb: fsl_mxc_udc.c: Remove compile-time dependency of MX35 SoC type
usb: fsl_mxc_udc.c: Fix build issue by including missing header file
USB: fsl_udc_core: use usb_endpoint_xfer_isoc to judge ISO XFER
usb: udc: Fix gadget driver's speed check in various UDC drivers
usb: gadget: fix g_serial regression
usb: renesas_usbhs: fixup driver speed
usb: renesas_usbhs: fixup gadget.dev.driver when udc_stop.
usb: renesas_usbhs: fixup signal the driver that cable was disconnected
usb: renesas_usbhs: fixup device_register timing
usb: musb: PM: fix context save/restore in suspend/resume path
USB: linux-cdc-acm.inf: add support for the acm_ms gadget
EHCI : Fix a regression in the ISO scheduler
xHCI: reset-on-resume quirk for NEC uPD720200
USB: whci-hcd: fix endian conversion in qset_clear()
USB: usb-storage: unusual_devs entry for Kingston DT 101 G2
usb: option: add SIMCom SIM5218
...
This patch adds kmemleak callbacks from the percpu allocator, reducing a
number of false positives caused by kmemleak not scanning such memory
blocks. The percpu chunks are never reported as leaks because of current
kmemleak limitations with the __percpu pointer not pointing directly to
the actual chunks.
Reported-by: Huajun Li <huajun.li.lee@gmail.com>
Acked-by: Christoph Lameter <cl@gentwo.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This driver works with both, static platform data and device tree
bindings. It has been tested on a TQM855L board with two AN82527
CAN controllers on the local bus.
CC: Devicetree-discuss@lists.ozlabs.org
CC: linuxppc-dev@ozlabs.org
CC: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix meta data raid-repair merge problem
Btrfs: skip allocation attempt from empty cluster
Btrfs: skip block groups without enough space for a cluster
Btrfs: start search for new cluster at the beginning
Btrfs: reset cluster's max_size when creating bitmap
Btrfs: initialize new bitmaps' list
Btrfs: fix oops when calling statfs on readonly device
Btrfs: Don't error on resizing FS to same size
Btrfs: fix deadlock on metadata reservation when evicting a inode
Fix URL of btrfs-progs git repository in docs
btrfs scrub: handle -ENOMEM from init_ipath()
There exist tilt switches that simply report their tilt-state via
some gpios. The number and orientation of their axes can vary
depending on the switch used and the build of the device. Also two
or more one-axis switches could be combined to provide multi-dimensional
orientation.
One example of a device using such a switch is the family of Qisda
ebook readers, where the switch provides information about the
landscape / portrait orientation of the device. The example in
Documentation/input/gpio-tilt.txt documents exactly this one-axis
device.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Rick Jones reported that TCP_CONGESTION sockopt performed on a listener
was ignored for its children sockets : right after accept() the
congestion control for new socket is the system default one.
This seems an oversight of the initial design (quoted from Stephen)
Based on prior investigation and patch from Rick.
Reported-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Yuchung Cheng <ycheng@google.com>
Tested-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>