Commit graph

68,868 commits

Author SHA1 Message Date
Ingo Molnar
6273143359 Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull the v3.18 RCU changes from Paul E. McKenney:

"
  * Update RCU documentation.  These were posted to LKML at
    https://lkml.org/lkml/2014/8/28/378.

  * Miscellaneous fixes.  These were posted to LKML at
    https://lkml.org/lkml/2014/8/28/386.  An additional fix that
    eliminates a documented (but now inconvenient) deadlock between
    RCU hotplug and expedited grace periods was posted at
    https://lkml.org/lkml/2014/8/28/573.

  * Changes related to No-CBs CPUs and NO_HZ_FULL.  These were posted
    to LKML at https://lkml.org/lkml/2014/8/28/412.

  * Torture-test updates.  These were posted to LKML at
    https://lkml.org/lkml/2014/8/28/546 and at
    https://lkml.org/lkml/2014/9/11/1114.

  * RCU-tasks implementation.  These were posted to LKML at
    https://lkml.org/lkml/2014/8/28/540.
"

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-23 07:21:42 +02:00
Linus Torvalds
7c9a3730a5 Merge branch 'for-3.17-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fix from Tejun Heo:
 "create_singlethread_workqueue() is the old interface which is kept
  around for backward compatibility - each should be reviewed to
  determine whether singlethread usage was to save worker threads or for
  ordering guarantee and whether it's depended upon by memory reclaim
  path.

  While adding NUMA support for unbound workqueues during v3.10, I
  forgot to update it breaking the singlethread and ordering properties
  on NUMA setups.  The breakage was unfortunately rather subtle and went
  without being reported until now.

  The only missing piece is __WQ_ORDERED flag which makes the unbounded
  workqueue use a single backend queue across different NUMA nodes.
  It's fixed by making create_singlethread_workqueue() wrap
  alloc_ordered_workqueue() so that possible future updates are
  inherited automatically"

* 'for-3.17-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: apply __WQ_ORDERED to create_singlethread_workqueue()
2014-09-22 08:42:55 -07:00
Linus Torvalds
3c2ea7024a Staging / IIO fixes for 3.17-rc6
Here are some IIO and Staging driver fixes for 3.17-rc6.  They are all
 pretty simple, and resolve reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-3.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging / IIO fixes from Greg KH:
 "Here are some IIO and Staging driver fixes for 3.17-rc6.  They are all
  pretty simple, and resolve reported issues"

* tag 'staging-3.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: vt6655: buffer overflow in ioctl
  iio:magnetometer: bugfix magnetometers gain values
  iio: adc: at91: don't use the last converted data register
  iio: adc: xilinx-xadc: assign auxiliary channels address correctly
  iio: meter: ade7758: Fix indio_dev->trig assignment
  iio: inv_mpu6050: Fix indio_dev->trig assignment
  iio: gyro: itg3200: Fix indio_dev->trig assignment
  iio: st_sensors: Fix indio_dev->trig assignment
  iio: hid_sensor_hub: Fix indio_dev->trig assignment
  iio: adc: ad_sigma_delta: Fix indio_dev->trig assignment
  iio: accel: bma180: Fix indio_dev->trig assignment
  iio:trigger: modify return value for iio_trigger_get
  iio:inkern: fix overwritten -EPROBE_DEFER in of_iio_channel_get_by_name
2014-09-20 10:43:37 -07:00
Linus Torvalds
1734a6e47f Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
 "A bunch of radeon fixes for oops on module unload, and problems with
  resetting the dma engine, one nouveau fix for black boxes in rendering
  on my mbp retina, one sti fix, and a couple of intel fixes"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/nouveau: ltc/gf100-: fix cbc issues on certain boards
  drm/bochs: add missing drm_connector_register call
  drm/cirrus: add missing drm_connector_register call
  drm/radeon: Fix typo 'addr' -> 'entry' in rs400_gart_set_page
  drm/nouveau/runpm: fix module unload
  drm/radeon/px: fix module unload
  vgaswitcheroo: add vga_switcheroo_fini_domain_pm_ops
  drm/radeon: don't reset dma on r6xx-evergreen init
  drm/radeon: don't reset sdma on CIK init
  drm/radeon: don't reset dma on NI/SI init
  drm/radeon/dpm: fix resume on mullins
  drm/radeon: Disable HDP flush before every CS again for < r600
  drm/radeon: delete unused PTE_* defines
  drm/i915: Add limited color range readout for HDMI/DP ports on g4x/vlv/chv
  drm: sti: do not iterate over the info frame array
  drm/i915: Fix SRC_COPY width on 830/845g
2014-09-20 10:10:14 -07:00
Greg Kroah-Hartman
922b83b4aa First round of IIO fixes for the 3.17 cycle.
* Fix an overwritten error return that can prevent deferred probing when
   using of_iio_channel_get_by_name
 * A series that deals with an incorrect reference count when the default
   trigger is set within the main probe routine for a driver.  Can result
   in a double free if the trigger is changed.
 * Fix a buglet with xilinx-xadc concerning setup of the address for an
   aux channel.
 * At91 adc driver could sometimes get a touchscreen reading rather than
   the intended adc channel.  This is fixed by using the channel data register
   instead.
 * Fix some ST magnetometer gain values that differ in production parts from
   the prerelease ones used for driver development.
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Merge tag 'iio-fixes-3.17a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

First round of IIO fixes for the 3.17 cycle.

* Fix an overwritten error return that can prevent deferred probing when
  using of_iio_channel_get_by_name
* A series that deals with an incorrect reference count when the default
  trigger is set within the main probe routine for a driver.  Can result
  in a double free if the trigger is changed.
* Fix a buglet with xilinx-xadc concerning setup of the address for an
  aux channel.
* At91 adc driver could sometimes get a touchscreen reading rather than
  the intended adc channel.  This is fixed by using the channel data register
  instead.
* Fix some ST magnetometer gain values that differ in production parts from
  the prerelease ones used for driver development.
2014-09-19 15:29:39 -07:00
Linus Torvalds
b29f83aa8b PCI updates for v3.17:
Enumeration
     - Don't default exclusively to first video device (Bruno Prémont)
 
   PCI device hotplug
     - Remove "no hotplug settings from platform" warning (Bjorn Helgaas)
     - Add pci_ignore_hotplug() for VGA switcheroo (Bjorn Helgaas)
 
   Freescale i.MX6
     - Put LTSSM in "Detect" state before disabling (Lucas Stach)
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Merge tag 'pci-v3.17-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI fixes from Bjorn Helgaas:
 "These fix:

   - Boot video device detection on dual-GPU Apple systems
   - Hotplug fiascos on VGA switcheroo with radeon & nouveau drivers
   - Boot hang on Freescale i.MX6 systems
   - Excessive "no hotplug settings from platform" warnings

  In particular:

  Enumeration
    - Don't default exclusively to first video device (Bruno Prémont)

  PCI device hotplug
    - Remove "no hotplug settings from platform" warning (Bjorn Helgaas)
    - Add pci_ignore_hotplug() for VGA switcheroo (Bjorn Helgaas)

  Freescale i.MX6
    - Put LTSSM in "Detect" state before disabling (Lucas Stach)"

* tag 'pci-v3.17-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  vgaarb: Drop obsolete #ifndef
  vgaarb: Don't default exclusively to first video device with mem+io
  ACPIPHP / radeon / nouveau: Remove acpi_bus_no_hotplug()
  PCI: Remove "no hotplug settings from platform" warning
  PCI: Add pci_ignore_hotplug() to ignore hotplug events for a device
  PCI: imx6: Put LTSSM in "Detect" state before disabling it
  MAINTAINERS: Add Lucas Stach as co-maintainer for i.MX6 PCI driver
2014-09-19 10:50:30 -07:00
Christoph Hellwig
e8be1cf58d [SCSI] fix regression that accidentally disabled block-based tcq
The scsi blk-mq support accidentally flipped a conditional, which lead to
never enabling block based tcq when using the legacy request path.

Fixes: d285203cf6 scsi: add support for a blk-mq based I/O path.
Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-09-19 13:23:32 +01:00
Bjorn Helgaas
649ae75286 Merge branch 'pci/vga'; commit '6a73336bde' into for-linus
* pci/vga:
  vgaarb: Drop obsolete #ifndef
  vgaarb: Don't default exclusively to first video device with mem+io

* commit '6a73336bde':
  PCI: Remove "no hotplug settings from platform" warning
2014-09-18 23:05:06 -06:00
Dave Airlie
b5591bd6a6 Merge branch 'drm-fixes-3.17' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
- fix a resume hang on mullins
- fix an oops on module unload with vgaswitcheroo (radeon and nouveau)
- fix possible hangs DMA engine hangs due to hw bugs

* 'drm-fixes-3.17' of git://people.freedesktop.org/~agd5f/linux:
  drm/nouveau/runpm: fix module unload
  drm/radeon/px: fix module unload
  vgaswitcheroo: add vga_switcheroo_fini_domain_pm_ops
  drm/radeon: don't reset dma on r6xx-evergreen init
  drm/radeon: don't reset sdma on CIK init
  drm/radeon: don't reset dma on NI/SI init
  drm/radeon/dpm: fix resume on mullins
  drm/radeon: Disable HDP flush before every CS again for < r600
  drm/radeon: delete unused PTE_* defines
2014-09-19 10:34:06 +10:00
Paul E. McKenney
dd56af42bd rcu: Eliminate deadlock between CPU hotplug and expedited grace periods
Currently, the expedited grace-period primitives do get_online_cpus().
This greatly simplifies their implementation, but means that calls
to them holding locks that are acquired by CPU-hotplug notifiers (to
say nothing of calls to these primitives from CPU-hotplug notifiers)
can deadlock.  But this is starting to become inconvenient, as can be
seen here: https://lkml.org/lkml/2014/8/5/754.  The problem in this
case is that some developers need to acquire a mutex from a CPU-hotplug
notifier, but also need to hold it across a synchronize_rcu_expedited().
As noted above, this currently results in deadlock.

This commit avoids the deadlock and retains the simplicity by creating
a try_get_online_cpus(), which returns false if the get_online_cpus()
reference count could not immediately be incremented.  If a call to
try_get_online_cpus() returns true, the expedited primitives operate as
before.  If a call returns false, the expedited primitives fall back to
normal grace-period operations.  This falling back of course results in
increased grace-period latency, but only during times when CPU hotplug
operations are actually in flight.  The effect should therefore be
negligible during normal operation.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Tested-by: Lan Tianyu <tianyu.lan@intel.com>
2014-09-18 16:22:27 -07:00
Alex Deucher
766a53d059 vgaswitcheroo: add vga_switcheroo_fini_domain_pm_ops
Drivers should call this on unload to unregister pmops.

Bug:
https://bugzilla.kernel.org/show_bug.cgi?id=84431

Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
2014-09-18 19:21:20 -04:00
Bruno Prémont
ce6eacb07e vgaarb: Drop obsolete #ifndef
Commit 20cde69402 ("x86, ia64: Move EFI_FB vga_default_device()
initialization to pci_vga_fixup()") moved boot video device detection from
efifb to x86 and ia64 pci/fixup.c.

Remove the left-over #ifndef check that will always match since the
corresponding arch-specific define is gone with above patch.

Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Matthew Garrett <matthew.garrett@nebula.com>
2014-09-16 15:02:55 -06:00
Paul E. McKenney
59da22a020 rcutorture: Rename rcutorture_runnable parameter
This commit changes rcutorture_runnable to torture_runnable, which is
consistent with the names of the other parameters and is a bit shorter
as well.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-16 13:41:44 -07:00
Davidlohr Bueso
d36a7a0d5e torture: Address race in module cleanup
When performing module cleanups by calling torture_cleanup() the
'torture_type' string in nullified However, callers are not necessarily
done, and might still need to reference the variable. This impacts
both rcutorture and locktorture, causing printing things like:

[   94.226618] (null)-torture: Stopping lock_torture_writer task
[   94.226624] (null)-torture: Stopping lock_torture_stats task

Thus delay this operation until the very end of the cleanup process.
The consequence (which shouldn't matter for this kid of program) is,
of course, that we delay the window between rmmod and modprobing,
for instance in module_torture_begin().

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-16 13:41:06 -07:00
Paul E. McKenney
96b4672703 Merge branch 'rcu-tasks.2014.09.10a' into HEAD
rcu-tasks.2014.09.10a: Add RCU-tasks flavor of RCU.
2014-09-16 10:10:44 -07:00
Paul E. McKenney
e98d06dd6c Merge branches 'doc.2014.09.07a', 'fixes.2014.09.10a', 'nocb-nohz.2014.09.16b' and 'torture.2014.09.07a' into HEAD
doc.2014.09.07a: Documentation updates.
fixes.2014.09.10a: Miscellaneous fixes.
nocb-nohz.2014.09.16b: No-CBs CPUs and NO_HZ_FULL updates.
torture.2014.09.07a: Torture-test updates.
2014-09-16 10:08:34 -07:00
Paul E. McKenney
f4579fc57c rcu: Fix attempt to avoid unsolicited offloading of callbacks
Commit b58cc46c5f (rcu: Don't offload callbacks unless specifically
requested) failed to adjust the callback lists of the CPUs that are
known to be no-CBs CPUs only because they are also nohz_full= CPUs.
This failure can result in callbacks that are posted during early boot
getting stranded on nxtlist for CPUs whose no-CBs property becomes
apparent late, and there can also be spurious warnings about offline
CPUs posting callbacks.

This commit fixes these problems by adding an early-boot rcu_init_nohz()
that properly initializes the no-CBs CPUs.

Note that kernels built with CONFIG_RCU_NOCB_CPU_ALL=y or with
CONFIG_RCU_NOCB_CPU=n do not exhibit this bug.  Neither do kernels
booted without the nohz_full= boot parameter.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2014-09-16 10:07:59 -07:00
Bjorn Helgaas
f91ce35e47 ACPIPHP / radeon / nouveau: Remove acpi_bus_no_hotplug()
Revert parts of f244d8b623 ("ACPIPHP / radeon / nouveau: Fix VGA
switcheroo problem related to hotplug").

A previous commit 5493b31f0b55 ("PCI: Add pci_ignore_hotplug() to ignore
hotplug events for a device") added equivalent functionality implemented in
a different way for both acpiphp and pciehp.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Rajat Jain <rajatxjain@gmail.com>
2014-09-15 13:15:34 -06:00
Linus Torvalds
3630056d96 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 "This fixes the newly added drbg generator so that it actually works on
  32-bit machines.  Previously the code was only tested on 64-bit and on
  32-bit it overflowed and simply doesn't work"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: drbg - remove check for uninitialized DRBG handle
  crypto: drbg - backport "fix maximum value checks on 32 bit systems"
2014-09-15 07:23:21 -07:00
Linus Torvalds
9226b5b440 vfs: avoid non-forwarding large load after small store in path lookup
The performance regression that Josef Bacik reported in the pathname
lookup (see commit 99d263d4c5 "vfs: fix bad hashing of dentries") made
me look at performance stability of the dcache code, just to verify that
the problem was actually fixed.  That turned up a few other problems in
this area.

There are a few cases where we exit RCU lookup mode and go to the slow
serializing case when we shouldn't, Al has fixed those and they'll come
in with the next VFS pull.

But my performance verification also shows that link_path_walk() turns
out to have a very unfortunate 32-bit store of the length and hash of
the name we look up, followed by a 64-bit read of the combined hash_len
field.  That screws up the processor store to load forwarding, causing
an unnecessary hickup in this critical routine.

It's caused by the ugly calling convention for the "hash_name()"
function, and easily fixed by just making hash_name() fill in the whole
'struct qstr' rather than passing it a pointer to just the hash value.

With that, the profile for this function looks much smoother.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-14 17:28:32 -07:00
Linus Torvalds
1536340e7c Merge branches 'locking-urgent-for-linus' and 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull futex and timer fixes from Thomas Gleixner:
 "A oneliner bugfix for the jinxed futex code:

   - Drop hash bucket lock in the error exit path.  I really could slap
     myself for intruducing that bug while fixing all the other horror
     in that code three month ago ...

  and the timer department is not too proud about the following fixes:

   - Deal with a long standing rounding bug in the timeval to jiffies
     conversion.  It's a real issue and this fix fell through the cracks
     for quite some time.

   - Another round of alarmtimer fixes.  Finally this code gets used
     more widely and the subtle issues hidden for quite some time are
     noticed and fixed.  Nothing really exciting, just the itty bitty
     details which bite the serious users here and there"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: Unlock hb->lock in futex_wait_requeue_pi() error path

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  alarmtimer: Lock k_itimer during timer callback
  alarmtimer: Do not signal SIGEV_NONE timers
  alarmtimer: Return relative times in timer_gettime
  jiffies: Fix timeval conversion to jiffies
2014-09-13 14:22:12 -07:00
Linus Torvalds
23d0db76ff Make hash_64() use a 64-bit multiply when appropriate
The hash_64() function historically does the multiply by the
GOLDEN_RATIO_PRIME_64 number with explicit shifts and adds, because
unlike the 32-bit case, gcc seems unable to turn the constant multiply
into the more appropriate shift and adds when required.

However, that means that we generate those shifts and adds even when the
architecture has a fast multiplier, and could just do it better in
hardware.

Use the now-cleaned-up CONFIG_ARCH_HAS_FAST_MULTIPLIER (together with
"is it a 64-bit architecture") to decide whether to use an integer
multiply or the explicit sequence of shift/add instructions.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-13 11:24:03 -07:00
Linus Torvalds
fc486b03ca Fix "xen_add_mach_to_phys_entry: cannot add" problem on xen on arm and
arm64.
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Merge tag 'stable/for-linus-3.17-b-rc4-arm-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen ARM bugfix from Stefano Stabellini:
 "The patches fix the "xen_add_mach_to_phys_entry: cannot add" bug that
  has been affecting xen on arm and arm64 guests since 3.16.  They
  require a few hypervisor side changes that just went in xen-unstable.

  A couple of days ago David sent out a pull request with a few other
  Xen fixes (it is already in master).  Sorry we didn't synchronized
  better among us"

* tag 'stable/for-linus-3.17-b-rc4-arm-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/arm: remove mach_to_phys rbtree
  xen/arm: reimplement xen_dma_unmap_page & friends
  xen/arm: introduce XENFEAT_grant_map_identity
2014-09-12 17:45:27 -07:00
Andrew Hunter
d78c9300c5 jiffies: Fix timeval conversion to jiffies
timeval_to_jiffies tried to round a timeval up to an integral number
of jiffies, but the logic for doing so was incorrect: intervals
corresponding to exactly N jiffies would become N+1. This manifested
itself particularly repeatedly stopping/starting an itimer:

setitimer(ITIMER_PROF, &val, NULL);
setitimer(ITIMER_PROF, NULL, &val);

would add a full tick to val, _even if it was exactly representable in
terms of jiffies_ (say, the result of a previous rounding.)  Doing
this repeatedly would cause unbounded growth in val.  So fix the math.

Here's what was wrong with the conversion: we essentially computed
(eliding seconds)

jiffies = usec  * (NSEC_PER_USEC/TICK_NSEC)

by using scaling arithmetic, which took the best approximation of
NSEC_PER_USEC/TICK_NSEC with denominator of 2^USEC_JIFFIE_SC =
x/(2^USEC_JIFFIE_SC), and computed:

jiffies = (usec * x) >> USEC_JIFFIE_SC

and rounded this calculation up in the intermediate form (since we
can't necessarily exactly represent TICK_NSEC in usec.) But the
scaling arithmetic is a (very slight) *over*approximation of the true
value; that is, instead of dividing by (1 usec/ 1 jiffie), we
effectively divided by (1 usec/1 jiffie)-epsilon (rounding
down). This would normally be fine, but we want to round timeouts up,
and we did so by adding 2^USEC_JIFFIE_SC - 1 before the shift; this
would be fine if our division was exact, but dividing this by the
slightly smaller factor was equivalent to adding just _over_ 1 to the
final result (instead of just _under_ 1, as desired.)

In particular, with HZ=1000, we consistently computed that 10000 usec
was 11 jiffies; the same was true for any exact multiple of
TICK_NSEC.

We could possibly still round in the intermediate form, adding
something less than 2^USEC_JIFFIE_SC - 1, but easier still is to
convert usec->nsec, round in nanoseconds, and then convert using
time*spec*_to_jiffies.  This adds one constant multiplication, and is
not observably slower in microbenchmarks on recent x86 hardware.

Tested: the following program:

int main() {
  struct itimerval zero = {{0, 0}, {0, 0}};
  /* Initially set to 10 ms. */
  struct itimerval initial = zero;
  initial.it_interval.tv_usec = 10000;
  setitimer(ITIMER_PROF, &initial, NULL);
  /* Save and restore several times. */
  for (size_t i = 0; i < 10; ++i) {
    struct itimerval prev;
    setitimer(ITIMER_PROF, &zero, &prev);
    /* on old kernels, this goes up by TICK_USEC every iteration */
    printf("previous value: %ld %ld %ld %ld\n",
           prev.it_interval.tv_sec, prev.it_interval.tv_usec,
           prev.it_value.tv_sec, prev.it_value.tv_usec);
    setitimer(ITIMER_PROF, &prev, NULL);
  }
    return 0;
}

Cc: stable@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Turner <pjt@google.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Reviewed-by: Paul Turner <pjt@google.com>
Reported-by: Aaron Jacobs <jacobsa@google.com>
Signed-off-by: Andrew Hunter <ahh@google.com>
[jstultz: Tweaked to apply to 3.17-rc]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-09-12 13:59:03 -07:00
Tejun Heo
e09c2c2954 workqueue: apply __WQ_ORDERED to create_singlethread_workqueue()
create_singlethread_workqueue() is a compat interface for single
threaded workqueue which maps to ordered workqueue w/ rescuer in the
current implementation.  create_singlethread_workqueue() currently
implemented by invoking alloc_workqueue() w/ appropriate parameters.

8719dceae2 ("workqueue: reject adjusting max_active or applying
attrs to ordered workqueues") introduced __WQ_ORDERED to protect
ordered workqueues against dynamic attribute changes which can break
ordering guarantees but forgot to apply it to
create_singlethread_workqueue().  This in itself is okay as nobody
currently uses dynamic attribute change on workqueues created with
create_singlethread_workqueue().

However, 4c16bd327c ("workqueue: implement NUMA affinity for unbound
workqueues") broke singlethreaded guarantee for ordered workqueues
through allocating a separate pool_workqueue on each NUMA node by
default.  A later change 8a2b753844 ("workqueue: fix ordered
workqueues in NUMA setups") fixed it by allocating only one global
pool_workqueue if __WQ_ORDERED is set.

Combined, the __WQ_ORDERED omission in create_singlethread_workqueue()
became critical breaking its single threadedness and ordering
guarantee.

Let's make create_singlethread_workqueue() wrap
alloc_ordered_workqueue() instead so that it inherits __WQ_ORDERED and
can implicitly track future ordered_workqueue changes.

v2: I missed that __WQ_ORDERED now protects against pwq splitting
    across NUMA nodes and incorrectly described the patch as a
    nice-to-have fix to protect against future dynamic attribute
    usages.  Oleg pointed out that this is actually a critical
    breakage due to 8a2b753844 ("workqueue: fix ordered workqueues
    in NUMA setups").

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Mike Anderson <mike.anderson@us.ibm.com>
Cc: Oleg Nesterov <onestero@redhat.com>
Cc: Gustavo Luiz Duarte <gduarte@redhat.com>
Cc: Tomas Henzl <thenzl@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 4c16bd327c ("workqueue: implement NUMA affinity for unbound workqueues")
2014-09-13 05:13:08 +09:00
Linus Torvalds
90a3c48fbf USB fixes for 3.17-rc5
Here are some USB and PHY fixes for 3.17-rc5.
 
 Nothing major here, just a number of tiny fixes for reported issues, and
 some new device ids as well.
 
 All have been tested in linux-next.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.17-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are some USB and PHY fixes for 3.17-rc5.

  Nothing major here, just a number of tiny fixes for reported issues,
  and some new device ids as well.

  All have been tested in linux-next"

* tag 'usb-3.17-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (46 commits)
  xhci: fix oops when xhci resumes from hibernate with hw lpm capable devices
  usb: xhci: Fix OOPS in xhci error handling code
  xhci: Fix null pointer dereference if xhci initialization fails
  storage: Add single-LUN quirk for Jaz USB Adapter
  uas: Add missing le16_to_cpu calls to asm1051 / asm1053 usb-id check
  usb: chipidea: msm: Initialize PHY on reset event
  usb: chipidea: msm: Use USB PHY API to control PHY state
  usb: hub: take hub->hdev reference when processing from eventlist
  uas: Disable uas on ASM1051 devices
  usb: dwc2/gadget: avoid disabling ep0
  usb: dwc2/gadget: delay enabling irq once hardware is configured properly
  usb: dwc2/gadget: do not call disconnect method in pullup
  usb: dwc2/gadget: break infinite loop in endpoint disable code
  usb: dwc2/gadget: fix phy initialization sequence
  usb: dwc2/gadget: fix phy disable sequence
  uwb: init beacon cache entry before registering uwb device
  USB: ftdi_sio: Add support for GE Healthcare Nemo Tracker device
  USB: document the 'u' flag for usb-storage quirks parameter
  usb: host: xhci: fix compliance mode workaround
  usb: dwc3: fix TRB completion when multiple TRBs are started
  ...
2014-09-12 11:59:10 -07:00
Stefano Stabellini
5ebc77de83 xen/arm: introduce XENFEAT_grant_map_identity
The flag tells us that the hypervisor maps a grant page to guest
physical address == machine address of the page in addition to the
normal grant mapping address. It is needed to properly issue cache
maintenance operation at the completion of a DMA operation involving a
foreign grant.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Denis Schneider <v1ne2go@gmail.com>
2014-09-11 18:11:52 +00:00
Linus Torvalds
c8c16e3624 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:
 "An update to Synaptics PS/2 driver to handle "ForcePads" (currently
  found in HP EliteBook 1040 laptops), a change for Elan PS/2 driver to
  detect newer touchpads, bunch of devices get annotated as Trackpoint
  and/or Pointer to help userspace classify and handle them, plus
  assorted driver fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: serport - add compat handling for SPIOCSTYPE ioctl
  Input: atmel_mxt_ts - fix double free of input device
  Input: synaptics - add support for ForcePads
  Input: matrix_keypad - use request_any_context_irq()
  Input: atmel_mxt_ts - downgrade warning about empty interrupts
  Input: wm971x - fix typo in module parameter description
  Input: cap1106 - fix register definition
  Input: add missing POINTER / DIRECT properties to a bunch of drivers
  Input: add INPUT_PROP_POINTING_STICK property
  Input: elantech - fix detection of touchpad on ASUS s301l
2014-09-11 10:08:36 -07:00
David Drysdale
b01d072065 shm: add memfd.h to UAPI export list
The new header file memfd.h from commit 9183df25fe ("shm: add
memfd_create() syscall") should be exported.

Signed-off-by: David Drysdale <drysdale@google.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-10 15:42:12 -07:00
Bjorn Helgaas
b440bde74f PCI: Add pci_ignore_hotplug() to ignore hotplug events for a device
Powering off a hot-pluggable device, e.g., with pci_set_power_state(D3cold),
normally generates a hot-remove event that unbinds the driver.

Some drivers expect to remain bound to a device even while they power it
off and back on again.  This can be dangerous, because if the device is
removed or replaced while it is powered off, the driver doesn't know that
anything changed.  But some drivers accept that risk.

Add pci_ignore_hotplug() for use by drivers that know their device cannot
be removed.  Using pci_ignore_hotplug() tells the PCI core that hot-plug
events for the device should be ignored.

The radeon and nouveau drivers use this to switch between a low-power,
integrated GPU and a higher-power, higher-performance discrete GPU.  They
power off the unused GPU, but they want to remain bound to it.

This is a reimplementation of f244d8b623 ("ACPIPHP / radeon / nouveau:
Fix VGA switcheroo problem related to hotplug") but extends it to work with
both acpiphp and pciehp.

This fixes a problem where systems with dual GPUs using the radeon drivers
become unusable, freezing every few seconds (see bugzillas below).  The
resume of the radeon device may also fail, e.g.,

This fixes problems on dual GPU systems where the radeon driver becomes
unusable because of problems while suspending the device, as in bug 79701:

    [drm] radeon: finishing device.
    radeon 0000:01:00.0: Userspace still has active objects !
    radeon 0000:01:00.0: ffff8800cb4ec288 ffff8800cb4ec000 16384 4294967297 force free
    ...
    WARNING: CPU: 0 PID: 67 at /home/apw/COD/linux/drivers/gpu/drm/radeon/radeon_gart.c:234 radeon_gart_unbind+0xd2/0xe0 [radeon]()
    trying to unbind memory from uninitialized GART !

or while resuming it, as in bug 77261:

    radeon 0000:01:00.0: ring 0 stalled for more than 10158msec
    radeon 0000:01:00.0: GPU lockup ...
    radeon 0000:01:00.0: GPU pci config reset
    pciehp 0000:00:01.0:pcie04: Card not present on Slot(1-1)
    radeon 0000:01:00.0: GPU reset succeeded, trying to resume
    *ERROR* radeon: dpm resume failed
    radeon 0000:01:00.0: Wait for MC idle timedout !

Link: https://bugzilla.kernel.org/show_bug.cgi?id=77261
Link: https://bugzilla.kernel.org/show_bug.cgi?id=79701
Reported-by: Shawn Starr <shawn.starr@rogers.com>
Reported-by: Jose P. <lbdkmjdf@sharklasers.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Rajat Jain <rajatxjain@gmail.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Dave Airlie <airlied@redhat.com>
CC: stable@vger.kernel.org	# v3.15+
2014-09-10 13:45:01 -06:00
Hans de Goede
7611392fe8 Input: add INPUT_PROP_POINTING_STICK property
It is useful for userspace to know that there not dealing with a regular
mouse but rather with a pointing stick (e.g. a trackpoint) so that
userspace can e.g. automatically enable middle button scrollwheel
emulation.

It is impossible to tell the difference from the evdev info without
resorting to putting a list of device / driver names in userspace, this is
undesirable.

Add a property which allows userspace to see if a device is a pointing
stick, and set it on all the pointing stick drivers.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-09-08 14:58:11 -07:00
Linus Torvalds
b531f5dd9c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix skb leak in mac802154, from Martin Townsend

 2) Use select not depends on NF_NAT for NFT_NAT, from Pablo Neira
    Ayuso

 3) Fix union initializer bogosity in vxlan, from Gerhard Stenzel

 4) Fix RX checksum configuration in stmmac driver, from Giuseppe
    CAVALLARO

 5) Fix TSO with non-accelerated VLANs in e1000, e1000e, bna, ehea,
    i40e, i40evf, mvneta, and qlge, from Vlad Yasevich

 6) Fix capability checks in phy_init_eee(), from Giuseppe CAVALLARO

 7) Try high order allocations more sanely for SKBs, specifically if a
    high order allocation fails, fall back directly to zero order pages
    rather than iterating down one order at a time.  From Eric Dumazet

 8) Fix a memory leak in openvswitch, from Li RongQing

 9) amd-xgbe initializes wrong spinlock, from Thomas Lendacky

10) RTNL locking was busted in setsockopt for anycast and multicast, fix
    from Sabrina Dubroca

11) Fix peer address refcount leak in ipv6, from Nicolas Dichtel

12) DocBook typo fixes, from Masanari Iida

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (101 commits)
  ipv6: restore the behavior of ipv6_sock_ac_drop()
  amd-xgbe: Enable interrupts for all management counters
  amd-xgbe: Treat certain counter registers as 64 bit
  greth: moved TX ring cleaning to NAPI rx poll func
  cnic : Cleanup CONFIG_IPV6 & VLAN check
  net: treewide: Fix typo found in DocBook/networking.xml
  bnx2x: Fix link problems for 1G SFP RJ45 module
  3c59x: avoid panic in boomerang_start_xmit when finding page address:
  netfilter: add explicit Kconfig for NETFILTER_XT_NAT
  ipv6: use addrconf_get_prefix_route() to remove peer addr
  ipv6: fix a refcnt leak with peer addr
  net-timestamp: only report sw timestamp if reporting bit is set
  drivers/net/fddi/skfp/h/skfbi.h: Remove useless PCI_BASE_2ND macros
  l2tp: fix race while getting PMTU on PPP pseudo-wire
  ipv6: fix rtnl locking in setsockopt for anycast and multicast
  VMXNET3: Check for map error in vmxnet3_set_mc
  openvswitch: distinguish between the dropped and consumed skb
  amd-xgbe: Fix initialization of the wrong spin lock
  openvswitch: fix a memory leak
  netfilter: fix missing dependencies in NETFILTER_XT_TARGET_LOG
  ...
2014-09-07 19:56:38 -07:00
Paul E. McKenney
284a8c93af rcu: Per-CPU operation cleanups to rcu_*_qs() functions
The rcu_bh_qs(), rcu_preempt_qs(), and rcu_sched_qs() functions use
old-style per-CPU variable access and write to ->passed_quiesce even
if it is already set.  This commit therefore updates to use the new-style
per-CPU variable access functions and avoids the spurious writes.
This commit also eliminates the "cpu" argument to these functions because
they are always invoked on the indicated CPU.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:27:35 -07:00
Paul E. McKenney
1d082fd061 rcu: Remove local_irq_disable() in rcu_preempt_note_context_switch()
The rcu_preempt_note_context_switch() function is on a scheduling fast
path, so it would be good to avoid disabling irqs.  The reason that irqs
are disabled is to synchronize process-level and irq-handler access to
the task_struct ->rcu_read_unlock_special bitmask.  This commit therefore
makes ->rcu_read_unlock_special instead be a union of bools with a short
allowing single-access checks in RCU's __rcu_read_unlock().  This results
in the process-level and irq-handler accesses being simple loads and
stores, so that irqs need no longer be disabled.  This commit therefore
removes the irq disabling from rcu_preempt_note_context_switch().

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:27:34 -07:00
Paul E. McKenney
01a8133034 rcu: Remove redundant preempt_disable() from rcu_note_voluntary_context_switch()
In theory, synchronize_sched() requires a read-side critical section
to order against.  In practice, preemption can be thought of as
being disabled across every machine instruction, at least for those
machine instructions that are not in the idle loop and not on offline
CPUs.  So this commit removes the redundant preempt_disable() from
rcu_note_voluntary_context_switch().

Please note that the single instruction in question is the store of
zero to ->rcu_tasks_holdout.  The "if" is simply a performance optimization
that avoids unnecessary stores.  To see this, keep in mind that both
the "if" condition and the store are in a quiescent state.  Therefore,
even if the task is preempted for a full grace period (presumably due
to its having done a context switch beforehand), the store will be
recording a legitimate quiescent state.

Reported-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

Conflicts:
	include/linux/rcupdate.h
2014-09-07 16:27:32 -07:00
Paul E. McKenney
176f8f7a52 rcu: Make TASKS_RCU handle nohz_full= CPUs
Currently TASKS_RCU would ignore a CPU running a task in nohz_full=
usermode execution.  There would be neither a context switch nor a
scheduling-clock interrupt to tell TASKS_RCU that the task in question
had passed through a quiescent state.  The grace period would therefore
extend indefinitely.  This commit therefore makes RCU's dyntick-idle
subsystem record the task_struct structure of the task that is running
in dyntick-idle mode on each CPU.  The TASKS_RCU grace period can
then access this information and record a quiescent state on
behalf of any CPU running in dyntick-idle usermode.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:27:30 -07:00
Paul E. McKenney
69c604557c rcutorture: Add torture tests for RCU-tasks
This commit adds torture tests for RCU-tasks.  It also fixes a bug that
would segfault for an RCU flavor lacking a callback-barrier function.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2014-09-07 16:27:24 -07:00
Paul E. McKenney
3f95aa81d2 rcu: Make TASKS_RCU handle tasks that are almost done exiting
Once a task has passed exit_notify() in the do_exit() code path, it
is no longer on the task lists, and is therefore no longer visible
to rcu_tasks_kthread().  This means that an almost-exited task might
be preempted while within a trampoline, and this task won't be waited
on by rcu_tasks_kthread().  This commit fixes this bug by adding an
srcu_struct.  An exiting task does srcu_read_lock() just before calling
exit_notify(), and does the corresponding srcu_read_unlock() after
doing the final preempt_disable().  This means that rcu_tasks_kthread()
can do synchronize_srcu() to wait for all mostly-exited tasks to reach
their final preempt_disable() region, and then use synchronize_sched()
to wait for those tasks to finish exiting.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:27:22 -07:00
Paul E. McKenney
53c6d4edf8 rcu: Add synchronous grace-period waiting for RCU-tasks
It turns out to be easier to add the synchronous grace-period waiting
functions to RCU-tasks than to work around their absense in rcutorture,
so this commit adds them.  The key point is that the existence of
call_rcu_tasks() means that rcutorture needs an rcu_barrier_tasks().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:27:21 -07:00
Paul E. McKenney
bde6c3aa99 rcu: Provide cond_resched_rcu_qs() to force quiescent states in long loops
RCU-tasks requires the occasional voluntary context switch
from CPU-bound in-kernel tasks.  In some cases, this requires
instrumenting cond_resched().  However, there is some reluctance
to countenance unconditionally instrumenting cond_resched() (see
http://lwn.net/Articles/603252/), so this commit creates a separate
cond_resched_rcu_qs() that may be used in place of cond_resched() in
locations prone to long-duration in-kernel looping.

This commit currently instruments only RCU-tasks.  Future possibilities
include also instrumenting RCU, RCU-bh, and RCU-sched in order to reduce
IPI usage.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:27:20 -07:00
Paul E. McKenney
8315f42295 rcu: Add call_rcu_tasks()
This commit adds a new RCU-tasks flavor of RCU, which provides
call_rcu_tasks().  This RCU flavor's quiescent states are voluntary
context switch (not preemption!) and userspace execution (not the idle
loop -- use some sort of schedule_on_each_cpu() if you need to handle the
idle tasks.  Note that unlike other RCU flavors, these quiescent states
occur in tasks, not necessarily CPUs.  Includes fixes from Steven Rostedt.

This RCU flavor is assumed to have very infrequent latency-tolerant
updaters.  This assumption permits significant simplifications, including
a single global callback list protected by a single global lock, along
with a single task-private linked list containing all tasks that have not
yet passed through a quiescent state.  If experience shows this assumption
to be incorrect, the required additional complexity will be added.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:27:19 -07:00
Joe Perches
eea203fea3 rcu: Use pr_alert/pr_cont for printing logs
User pr_alert/pr_cont for printing the logs from rcutorture module directly
instead of writing it to a buffer and then printing it. This allows us from not
having to allocate such buffers. Also remove a resulting empty function.

I tested this using the parse-torture.sh script as follows:

$ dmesg | grep torture > log.txt
$ bash parse-torture.sh log.txt test
$

There were no warnings which means that parsing went fine.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:24:47 -07:00
Paul E. McKenney
9fdd3bc900 rcu: Break more call_rcu() deadlock involving scheduler and perf
Commit 96d3fd0d31 (rcu: Break call_rcu() deadlock involving scheduler
and perf) covered the case where __call_rcu_nocb_enqueue() needs to wake
the rcuo kthread due to the queue being initially empty, but did not
do anything for the case where the queue was overflowing.  This commit
therefore also defers wakeup for the overflow case.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:18:17 -07:00
Oleg Nesterov
85b39d305b rcu: Uninline rcu_read_lock_held()
This commit uninlines rcu_read_lock_held(). According to "size vmlinux"
this saves 28549 in .text:

	- 5541731 3014560 14757888 23314179
	+ 5513182 3026848 14757888 23297918

Note: it looks as if the data grows by 12288 bytes but this is not true,
it does not actually grow. But .data starts with ALIGN(THREAD_SIZE) and
since .text shrinks the padding grows, and thus .data grows too as it
seen by /bin/size. diff System.map:

	- ffffffff81510000 D _sdata
	- ffffffff81510000 D init_thread_union
	+ ffffffff81509000 D _sdata
	+ ffffffff8150c000 D init_thread_union

Perhaps we can change vmlinux.lds.S to .data itself, so that /bin/size
can't "wrongly" report that .data grows if .text shinks.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:18:13 -07:00
Pranith Kumar
521d24ee59 rcu: Return bool type in rcu_lockdep_current_cpu_online()
Return true instead of 1 in rcu_lockdep_current_cpu_online() as this
has bool as return type.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-07 16:18:11 -07:00
David S. Miller
45ce829dd0 Merge tag 'master-2014-09-04' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
John W. Linville says:

====================
pull request: wireless 2014-09-05

Please pull this batch of fixes intended for the 3.17 stream...

For the mac80211 bits, Johannes says:

"Here are a few fixes for mac80211. One has been discussed for a while
and adds a terminating NUL-byte to the alpha2 sent to userspace, which
shouldn't be necessary but since many places treat it as a string we
couldn't move to just sending two bytes.

In addition to that, we have two VLAN fixes from Felix, a mesh fix, a
fix for the recently introduced RX aggregation offload, a revert for
a broken patch (that luckily didn't really cause any harm) and a small
fix for alignment in debugfs."

For the iwlwifi bits, Emmanuel says:

"I revert a patch that disabled CTS to self in dvm because users
reported issues. The revert is CCed to stable since the offending
patch was sent to stable too. I also bump the firmware API versions
since a new firmware is coming up. On top of that, Marcel fixes a
bug I introduced while fixing a bug in our Kconfig file."

Please let me know if there are problems!
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-07 16:11:10 -07:00
Linus Torvalds
6fef37c9a7 ACPI and power management fixes for 3.17-rc4
- Fix for recently broken test_suspend= command line argument
    (Rafael J Wysocki).
 
  - Fixes for regressions related to the ACPI video driver caused
    by switching the default to native backlight handling in 3.16
    from Hans de Goede.
 
  - Fix for a sysfs attribute of ACPI device objects that returns
    stale values sometimes due to the fact that they are cached
    instead of executing the appropriate method (_SUN) every time
    (broken in 3.14).  From Yasuaki Ishimatsu.
 
  - Fix for a deadlock between cpuidle_lock and cpu_hotplug.lock
    in the ACPI processor driver from Jiri Kosina.
 
  - Runtime output validation for the ACPI _DSD device configuration
    object missing from the support for it that has been introduced
    recently.  From Mika Westerberg.
 
  - Fix for an unuseful and misleading RAPL (Running Average Power
    Limit) domain detection message in the RAPL driver from Jacob Pan.
 
  - New Intel Haswell CPU ID for the RAPL driver from Jason Baron.
 
  - New Clevo W350etq blacklist entry for the ACPI EC driver
    from Lan Tianyu.
 
  - Cleanup for the intel_pstate driver and the core generic PM
    domains code from Gabriele Mazzotta and Geert Uytterhoeven.
 
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Merge tag 'pm+acpi-3.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael Wysocki:
 "These are regression fixes (ACPI sysfs, ACPI video, suspend test),
  ACPI cpuidle deadlock fix, missing runtime validation of ACPI _DSD
  output, a fix and a new CPU ID for the RAPL driver, new blacklist
  entry for the ACPI EC driver and a couple of trivial cleanups
  (intel_pstate and generic PM domains).

  Specifics:

   - Fix for recently broken test_suspend= command line argument (Rafael
     Wysocki).

   - Fixes for regressions related to the ACPI video driver caused by
     switching the default to native backlight handling in 3.16 from
     Hans de Goede.

   - Fix for a sysfs attribute of ACPI device objects that returns stale
     values sometimes due to the fact that they are cached instead of
     executing the appropriate method (_SUN) every time (broken in
     3.14).  From Yasuaki Ishimatsu.

   - Fix for a deadlock between cpuidle_lock and cpu_hotplug.lock in the
     ACPI processor driver from Jiri Kosina.

   - Runtime output validation for the ACPI _DSD device configuration
     object missing from the support for it that has been introduced
     recently.  From Mika Westerberg.

   - Fix for an unuseful and misleading RAPL (Running Average Power
     Limit) domain detection message in the RAPL driver from Jacob Pan.

   - New Intel Haswell CPU ID for the RAPL driver from Jason Baron.

   - New Clevo W350etq blacklist entry for the ACPI EC driver from Lan
     Tianyu.

   - Cleanup for the intel_pstate driver and the core generic PM domains
     code from Gabriele Mazzotta and Geert Uytterhoeven"

* tag 'pm+acpi-3.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / cpuidle: fix deadlock between cpuidle_lock and cpu_hotplug.lock
  ACPI / scan: not cache _SUN value in struct acpi_device_pnp
  cpufreq: intel_pstate: Remove unneeded variable
  powercap / RAPL: change domain detection message
  powercap / RAPL: add support for CPU model 0x3f
  PM / domains: Make generic_pm_domain.name const
  PM / sleep: Fix test_suspend= command line option
  ACPI / EC: Add msi quirk for Clevo W350etq
  ACPI / video: Disable native_backlight on HP ENVY 15 Notebook PC
  ACPI / video: Add a disable_native_backlight quirk
  ACPI / video: Fix use_native_backlight selection logic
  ACPICA: ACPI 5.1: Add support for runtime validation of _DSD package.
2014-09-07 11:57:27 -07:00
Linus Torvalds
ebc54f278f Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "Three fixlets from the timer departement:

   - Update the timekeeper before updating vsyscall and pvclock.  This
     fixes the kvm-clock regression reported by Chris and Paolo.

   - Use the proper irq work interface from NMI.  This fixes the
     regression reported by Catalin and Dave.

   - Clarify the compat_nanosleep error handling mechanism to avoid
     future confusion"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Update timekeeper before updating vsyscall and pvclock
  compat: nanosleep: Clarify error handling
  nohz: Restore NMI safe local irq work for local nohz kick
2014-09-07 10:37:48 -07:00
Linus Torvalds
925e0ea47c Two trivial MTD updates for 3.17-rc4:
* A tiny comment tweak, to kill a bunch of DocBook warnings added during the
    merge window
 
  * A small fixup to the OTP routines' error handling
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Merge tag 'for-linus-20140905' of git://git.infradead.org/linux-mtd

Pull mtd fixes from Brian Norris:
 "Two trivial MTD updates for 3.17-rc4:

   - a tiny comment tweak, to kill a bunch of DocBook warnings added
     during the merge window

   - a small fixup to the OTP routines' error handling"

* tag 'for-linus-20140905' of git://git.infradead.org/linux-mtd:
  mtd: nand: fix DocBook warnings on nand_sdr_timings doc
  mtd: cfi_cmdset_0002: check return code for get_chip()
2014-09-06 12:12:09 -07:00
Masanari Iida
e793c0f70e net: treewide: Fix typo found in DocBook/networking.xml
This patch fix spelling typo found in DocBook/networking.xml.
It is because the neworking.xml is generated from comments
in the source, I have to fix typo in comments within the source.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-05 17:35:28 -07:00