When waiting for high frequency requests, the finite amount of time
required to set up the irq and wait upon it limits the response rate. By
busywaiting on the request completion for a short while we can service
the high frequency waits as quick as possible. However, if it is a slow
request, we want to sleep as quickly as possible. The tradeoff between
waiting and sleeping is roughly the time it takes to sleep on a request,
on the order of a microsecond. Based on measurements of synchronous
workloads from across big core and little atom, I have set the limit for
busywaiting as 10 microseconds. In most of the synchronous cases, we can
reduce the limit down to as little as 2 miscroseconds, but that leaves
quite a few test cases regressing by factors of 3 and more.

The code currently uses the jiffie clock, but that is far too coarse (on
the order of 10 milliseconds) and results in poor interactivity as the
CPU ends up being hogged by slow requests. To get microsecond resolution
we need to use a high resolution timer. The cheapest of which is polling
local_clock(), but that is only valid on the same CPU. If we switch CPUs
because the task was preempted, we can also use that as an indicator that
 the system is too busy to waste cycles on spinning and we should sleep
instead.

__i915_spin_request was introduced in
commit 2def4ad9 [v4.2]
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Apr 7 16:20:41 2015 +0100

     drm/i915: Optimistically spin for the request completion

v2: Drop full u64 for unsigned long - the timer is 32bit wraparound safe,
so we can use native register sizes on smaller architectures. Mention
the approximate microseconds units for elapsed time and add some extra
comments describing the reason for busywaiting.

v3: Raise the limit to 10us
v4: Now 5us.
Reported-by: Jens Axboe <axboe@kernel.dk>
Link: https://lkml.org/lkml/2015/11/12/621Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: "Rogozhkin, Dmitry V" <dmitry.v.rogozhkin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Eero Tamminen <eero.t.tamminen@intel.com>
Cc: "Rantala, Valtteri" <valtteri.rantala@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449833608-22125-3-git-send-email-chris@chris-wilson.co.uk
(cherry picked from commit ca5b721e)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

The busywait in __i915_spin_request() does not respect pending signals
and so may consume the entire timeslice for the task instead of
returning to userspace to handle the signal.

In the worst case this could cause a delay in signal processing of 20ms,
which would be a noticeable jitter in cursor tracking. If a higher
resolution signal was being used, for example to provide fairness of a
server timeslices between clients, we could expect to detect some
unfairness between clients (i.e. some windows not updating as fast as
others). This issue was noticed when inspecting a report of poor
interactivity resulting from excessively high __i915_spin_request usage.

Fixes regression from
commit 2def4ad9 [v4.2]
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Apr 7 16:20:41 2015 +0100

     drm/i915: Optimistically spin for the request completion

v2: Try to assess the impact of the bug
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc; "Rogozhkin, Dmitry V" <dmitry.v.rogozhkin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Eero Tamminen <eero.t.tamminen@intel.com>
Cc: "Rantala, Valtteri" <valtteri.rantala@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449833608-22125-2-git-send-email-chris@chris-wilson.co.uk
(cherry picked from commit 91b0c352)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

If we fail to reconstruct the BIOS fb (e.g., because the FB is too
large), we'll be left with plane state that indicates the primary plane
is visible yet has a NULL fb.  This mismatch causes problems later on
(e.g., for the watermark code).  Since we've failed to reconstruct the
BIOS FB, the best solution is to just disable the primary plane and
pretend the BIOS never had it enabled.

v2: Add intel_pre_disable_primary() call (Maarten)

Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449171462-30763-2-git-send-email-matthew.d.roper@intel.com
(cherry picked from commit 200757f5)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

As we mark the preallocated objects as bound, we should also flag them
correctly as being map-and-fenceable (if appropriate!) so that later
users do not get confused and try and rebind the pinned vma in order to
get a map-and-fenceable binding.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: "Goel, Akash" <akash.goel@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: drm-intel-fixes@lists.freedesktop.org
Link: http://patchwork.freedesktop.org/patch/msgid/1448029000-10616-1-git-send-email-chris@chris-wilson.co.ukReviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit d0710abb)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

The cursor code tries to treat base==0 to mean disabled. That fails
when the cursor bo gets bound at ggtt offset 0, and the user is left
looking at an invisible cursor.

We lose the disabled->disabled optimization, but that seems like
something better handled at a slightly higher level.

Cc: drm-intel-fixes@lists.freedesktop.org
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450091808-32607-3-git-send-email-ville.syrjala@linux.intel.comReviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
(cherry picked from commit 663f3122)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Pull RTC fixes from Alexandre Belloni:
 "Late fixes for the RTC subsystem for 4.4:

  A fix for a nasty hardware bug in rk808 and an initialization
  reordering in da9063 to fix a possible crash"

* tag 'rtc-4.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux:
  rtc: da9063: fix access ordering error during RTC interrupt at system power on
  rtc: rk808: Compensate for Rockchip calendar deviation on November 31st

This fix alters the ordering of the IRQ and device registrations in the RTC
driver probe function. This change will apply to the RTC driver that supports
both DA9063 and DA9062 PMICs.

A problem could occur with the existing RTC driver if:

A system is started from a cold boot using the PMIC RTC IRQ to initiate a
power on operation. For instance, if an RTC alarm is used to start a
platform from power off.
The existing driver IRQ is requested before the device has been properly
registered.
i.e.
    ret = devm_request_threaded_irq()
comes before
    rtc->rtc_dev = devm_rtc_device_register();

In this case, the interrupt can be called before the device has been
registered and the handler can be called immediately. The IRQ handler
da9063_alarm_event() contains the function call

    rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);

which in turn tries to access the unavailable rtc->rtc_dev.

The fix is to reorder the functions inside the RTC probe. The IRQ is
requested after the RTC device resource has been registered so that
get_irq_byname is the last thing to happen.
Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

In A.D. 1582 Pope Gregory XIII found that the existing Julian calendar
insufficiently represented reality, and changed the rules about
calculating leap years to account for this. Similarly, in A.D. 2013
Rockchip hardware engineers found that the new Gregorian calendar still
contained flaws, and that the month of November should be counted up to
31 days instead. Unfortunately it takes a long time for calendar changes
to gain widespread adoption, and just like more than 300 years went by
before the last Protestant nation implemented Greg's proposal, we will
have to wait a while until all religions and operating system kernels
acknowledge the inherent advantages of the Rockchip system. Until then
we need to translate dates read from (and written to) Rockchip hardware
back to the Gregorian format.

This patch works by defining Jan 1st, 2016 as the arbitrary anchor date
on which Rockchip and Gregorian calendars are in sync. From that we can
translate arbitrary later dates back and forth by counting the number
of November/December transitons since the anchor date to determine the
offset between the calendars. We choose this method (rather than trying
to regularly "correct" the date stored in hardware) since it's the only
way to ensure perfect time-keeping even if the system may be shut down
for an unknown number of years. The drawback is that other software
reading the same hardware (e.g. mainboard firmware) must use the same
translation convention (including the same anchor date) to be able to
read and write correct timestamps from/to the RTC.
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Pull tty/serial fixes from Greg KH:
 "Here are some tty/serial driver fixes for 4.4-rc6 that resolve some
  reported problems.  All of these have been in linux-next.  The details
  are in the shortlog"

* tag 'tty-4.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: Fix GPF in flush_to_ldisc()
  serial: earlycon: Add missing spinlock initialization
  serial: sh-sci: Fix length of scatterlist
  n_tty: Fix poll() after buffer-limited eof push read
  serial: 8250_uniphier: fix dl_read and dl_write functions

Pull USB fixes from Greg KH:
 "Here are some USB and PHY fixes for 4.4-rc6.  All of them resolve some
  reported problems.  Full details in the shortlog"

* tag 'usb-4.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: fix invalid memory access in hub_activate()
  USB: ipaq.c: fix a timeout loop
  phy: core: Get a refcount to phy in devm_of_phy_get_by_index()
  phy: cygnus: pcie: add missing of_node_put
  phy: miphy365x: add missing of_node_put
  phy: miphy28lp: add missing of_node_put
  phy: rockchip-usb: add missing of_node_put
  phy: berlin-sata: add missing of_node_put
  phy: mt65xx-usb3: add missing of_node_put
  phy: brcmstb-sata: add missing of_node_put
  phy: sun9i-usb: add USB dependency

Pull md fixes from Neil Brown:
 "Four fixes for md:

   - two recently introduced regressions fixed.
   - one older bug in RAID10 - tagged for -stable since 4.2
   - one minor sysfs api improvement"

* tag 'md/4.4-rc5-fixes' of git://neil.brown.name/md:
  Fix remove_and_add_spares removes drive added as spare in slot_store
  md: fix bug due to nested suspend
  MD: change journal disk role to disk 0
  md/raid10: fix data corruption and crash during resync

Pull powerpc fixes from Michael Ellerman:
 - Partial revert of "powerpc: Individual System V IPC system calls"
 - pr_warn_once on unsupported OPAL_MSG type from Stewart
 - Fix deadlock in opal-irqchip introduced by "Fix double endian
   conversion" from Alistair

* tag 'powerpc-4.4-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/opal-irqchip: Fix deadlock introduced by "Fix double endian conversion"
  powerpc/powernv: pr_warn_once on unsupported OPAL_MSG type
  Partial revert of "powerpc: Individual System V IPC system calls"

Pull spi fixes from Mark Brown:
 "A couple of reference counting bugs here, one in spidev and one with
  holding an extra reference in the core that we never freed if we
  removed a device, plus a driver specific fix.  Both of the refcounting
  bugs are very old but they've only been found by observation so
  hopefully their impact has been low"

* tag 'spi-fix-v4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: fix parent-device reference leak
  spi: spidev: Hold spi_lock over all defererences of spi in release()
  spi-fsl-dspi: Fix CTAR Register access

Pull GPIO fixes from Linus Walleij:
 "Some GPIO fixes for the v4.4 series.  Most prominent: I revert the
  error propagation from the .get() function until we can fix up all the
  drivers properly for v4.5.

   - Revert the error number propagation from the .get() vtable entry
     temporarily, until we make the proper fixes to all drivers.
   - Fix the clamping behaviour in the generic GPIO driver.
   - Driver fix for the ath79 driver"

* tag 'gpio-v4.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: revert get() to non-errorprogating behaviour
  gpio: generic: clamp values from bgpio_get_set()
  gpio: ath79: Fix the logic to clear offset bit of AR71XX_GPIO_REG_OE register

Pull pin control fixes from Linus Walleij:
 - Driver fixes for Freescale i.MX7D, Intel, Broadcom 2835
 - One MAINTAINERS entry

* tag 'pinctrl-v4.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  MAINTAINERS: pinctrl: Add maintainers for pinctrl-single
  pinctrl: bcm2835: Fix initial value for direction_output
  pinctrl: intel: fix offset calculation issue of register PAD_OWN
  pinctrl: intel: fix bug of register offset calculation
  pinctrl: freescale: add ZERO_OFFSET_VALID flag for vf610 pinctrl

Pull i2c fixes from Wolfram Sang:
 "A set of 'usual' driver bugfixes for the I2C subsystem"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: rcar: disable runtime PM correctly in slave mode
  i2c: designware: Keep pm_runtime_enable/_disable calls in sync
  i2c: designware: fix IO timeout issue for AMD controller
  i2c: imx: init bus recovery info before adding i2c adapter
  i2c: do not use 0x in front of %pa
  i2c: davinci: Increase module clock frequency
  i2c: mv64xxx: The n clockdiv factor is 0 based on sunxi SoCs
  i2c: rk3x: populate correct variable for sda_falling_time

Pull input fixes from Dmitry Torokhov:
 "Just a few assorted driver fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: elants_i2c - fix wake-on-touch
  Input: elan_i2c - set input device's vendor and product IDs
  Input: sun4i-lradc-keys - fix typo in binding documentation
  Input: atmel_mxt_ts - add maxtouch to I2C table for module autoload
  Input: arizona-haptic - fix disabling of haptics device
  Input: aiptek - fix crash on detecting device without endpoints
  Input: atmel_mxt_ts - add generic platform data for Chromebooks
  Input: parkbd - clear unused function pointers
  Input: walkera0701 - clear unused function pointers
  Input: turbografx - clear unused function pointers
  Input: gamecon - clear unused function pointers
  Input: db9 - clear unused function pointers

When we also are I2C slave, we need to disable runtime PM because the
address detection mechanism needs to be active all the time. However, we
can reenable runtime PM once the slave instance was unregistered. So,
use pm_runtime_get_sync/put to achieve this, since it has proper
refcounting. pm_runtime_allow/forbid is like a global knob controllable
from userspace which is unsuitable here.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

Pull power management fixes from Rafael Wysocki:
 "These fix a potential regression introduced during the 4.3 cycle
  (generic power domains framework), a nasty bug that has been present
  forever (power capping RAPL driver), a build issue (Tegra cpufreq
  driver) and a minor ugliness introduced recently (intel_pstate).

  Specifics:

   - Fix a potential regression in the generic power domains framework
     introduced during the 4.3 development cycle that may lead to
     spurious failures of system suspend in certain situations (Ulf
     Hansson).

   - Fix a problem in the power capping RAPL (Running Average Power
     Limits) driver that causes it to initialize successfully on some
     systems where it is not supposed to do that which is due to an
     incorrect check in an initialization routine (Prarit Bhargava).

   - Fix a build problem in the cpufreq Tegra driver that depends on the
     regulator framework, but that dependency is not reflected in
     Kconfig (Arnd Bergmann).

   - Fix a recent mistake in the intel_pstate driver where a numeric
     constant is used directly instead of a symbol defined specifically
     for the case in question (Prarit Bhargava)"

* tag 'pm+acpi-4.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  powercap / RAPL: fix BIOS lock check
  cpufreq: intel_pstate: Minor cleanup for FRAC_BITS
  cpufreq: tegra: add regulator dependency for T124
  PM / Domains: Allow runtime PM callbacks to be re-used during system PM

Pull SCSI fixes from James Bottomley:
 "Three fixes this time, two in SES picked up by KASAN for various types
  of buffer overrun.  The first is a USB array which returns page 8
  whatever is asked for and causes us to overrun with incorrect data
  format assumptions and the second is an invalid iteration of page 10
  (the additional information page).

  The final fix is a reversion of a NULL deref fix which caused
  suspend/resume not to be called in pairs leading to incorrect device
  operation (Jens has queued a more proper fix for the problem in
  block)"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  ses: fix additional element traversal bug
  Revert "SCSI: Fix NULL pointer dereference in runtime PM"
  ses: Fix problems with simple enclosures

When sending "SLEEP" command to the controller it ceases scanning
completely and is unable to wake the system up from sleep, so if it is
configured as a wakeup source we should simply configure interrupt for
wakeup and rely on idle logic within the controller to reduce power
consumption while it is not used.
Signed-off-by: James Chen <james.chen@emc.com.tw>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Pull media fixes from Mauro Carvalho Chehab.

* tag 'media/v4.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  [media] airspy: increase USB control message buffer size
  [media] hackrf: move RF gain ctrl enable behind module parameter
  [media] hackrf: fix possible null ptr on debug printing
  [media] Revert "[media] ivtv: avoid going past input/audio array"

Pull btrfs fixes from Chris Mason:
 "A couple of small fixes"

* 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: check prepare_uptodate_page() error code earlier
  Btrfs: check for empty bitmap list in setup_cluster_bitmaps
  btrfs: fix misleading warning when space cache failed to load
  Btrfs: fix transaction handle leak in balance
  Btrfs: fix unprotected list move from unused_bgs to deleted_bgs list

Merge misc fixes from Andrew Morton:
 "Three patches"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  include/linux/mmdebug.h: should include linux/bug.h
  mm/zswap: change incorrect strncmp use to strcmp
  proc: fix -ESRCH error when writing to /proc/$pid/coredump_filter

mmdebug.h uses BUILD_BUG_ON_INVALID(), assuming someone else included
linux/bug.h.  Include it ourselves.

This saves build-failures such as:

  arch/arm64/include/asm/pgtable.h: In function 'set_pte_at':
  arch/arm64/include/asm/pgtable.h:281:3: error: implicit declaration of function 'BUILD_BUG_ON_INVALID' [-Werror=implicit-function-declaration]
   VM_WARN_ONCE(!pte_young(pte),

Fixes: 02602a18 ("bug: completely remove code generated by disabled VM_BUG_ON()")
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Change the use of strncmp in zswap_pool_find_get() to strcmp.

The use of strncmp is no longer correct, now that zswap_zpool_type is
not an array; sizeof() will return the size of a pointer, which isn't
the right length to compare.  We don't need to use strncmp anyway,
because the existing params and the passed in params are all guaranteed
to be null terminated, so strcmp should be used.
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Reported-by: Weijie Yang <weijie.yang@samsung.com>
Cc: Seth Jennings <sjennings@variantweb.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Writing to /proc/$pid/coredump_filter always returns -ESRCH because commit
774636e1 ("proc: convert to kstrto*()/kstrto*_from_user()") removed
the setting of ret after the get_proc_task call and incorrectly left it as
-ESRCH.  Instead, return 0 when successful.

Example breakage:

  echo 0 > /proc/self/coredump_filter
  bash: echo: write error: No such process

Fixes: 774636e1 ("proc: convert to kstrto*()/kstrto*_from_user()")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org> [4.3+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'hwmon-for-linus-v4.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:

 - Select CONFIG_BITREVERSE for sht15 driver to avoid build failure if
   it is not configured.

 - Force wait for conversion time for the first valid data in tmp102
   driver to avoid reporting erroneous data to the thermal subsystem.

* tag 'hwmon-for-linus-v4.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (sht15) Select CONFIG_BITREVERSE
  hwmon: (tmp102) Force wait for conversion time for the first valid data

Pull IOMMU fixes from Joerg Roedel:
 "Two similar fixes for the Intel and AMD IOMMU drivers to add proper
  access checks before calling handle_mm_fault"

* tag 'iommu-fixes-v4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Do access checks before calling handle_mm_fault()
  iommu/amd: Do proper access checking before calling handle_mm_fault()

Pull xen bug fixes from David Vrabel:
 - XSA-155 security fixes to backend drivers.
 - XSA-157 security fixes to pciback.

* tag 'for-linus-4.4-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen-pciback: fix up cleanup path when alloc fails
  xen/pciback: Don't allow MSI-X ops if PCI_COMMAND_MEMORY is not set.
  xen/pciback: For XEN_PCI_OP_disable_msi[|x] only disable if device has MSI(X) enabled.
  xen/pciback: Do not install an IRQ handler for MSI interrupts.
  xen/pciback: Return error on XEN_PCI_OP_enable_msix when device has MSI or MSI-X enabled
  xen/pciback: Return error on XEN_PCI_OP_enable_msi when device has MSI or MSI-X enabled
  xen/pciback: Save xen_pci_op commands before processing it
  xen-scsiback: safely copy requests
  xen-blkback: read from indirect descriptors only once
  xen-blkback: only read request operation from shared ring once
  xen-netback: use RING_COPY_REQUEST() throughout
  xen-netback: don't use last request to determine minimum Tx credit
  xen: Add RING_COPY_REQUEST()
  xen/x86/pvh: Use HVM's flush_tlb_others op
  xen: Resume PMU from non-atomic context
  xen/events/fifo: Consume unprocessed events when a CPU dies

Pull ARC architecture fixes from Vineet Gupta:
 "Fixes for:

 - perf interrupts on SMP: Not enabled (at boot) and disabled (at runtime)
 - stack unwinder regression (for modules, ignoring dwarf3)
 - nsim hosed for non default kernel link base builds"

* tag 'arc-fixes-for-4.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: smp: Rename platform hook @init_cpu_smp -> @init_per_cpu
  ARC: rename smp operation init_irq_cpu() to init_per_cpu()
  ARC: dw2 unwind: Ignore CIE version !=1 gracefully instead of bailing
  ARC: dw2 unwind: Reinstante unwinding out of modules
  ARC: [plat-sim] unbork non default CONFIG_LINUX_LINK_BASE
  ARC: intc: Document arc_request_percpu_irq() better
  ARCv2: perf: Ensure perf intr gets enabled on all cores
  ARC: intc: No need to clear IRQ_NOAUTOEN
  ARCv2: intc: Fix random perf irq disabling in SMP setup
  ARC: [axs10x] cap ethernet phy to 100 Mbit/sec

Pull sound fixes from Takashi Iwai:
 "As usual in rc6, this update contains only a few HD-audio and
  USB-audio device-specific quirks: yet another Thinkpad noise fixes,
  Dell headphone mic fixes, and AudioQuest DragonFly fixes"

* tag 'sound-4.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Add a fixup for Thinkpad X1 Carbon 2nd
  ALSA: hda - Set codec to D3 at reboot/shutdown on Thinkpads
  ALSA: hda - Apply click noise workaround for Thinkpads generically
  ALSA: hda - Fix headphone mic input on a few Dell ALC293 machines
  ALSA: usb-audio: Add sample rate inquiry quirk for AudioQuest DragonFly
  ALSA: usb-audio: Add a more accurate volume quirk for AudioQuest DragonFly

Pull MTD fixes from Brian Norris:
 "I was holding out on this pull request for a bit, since there are a
  few other small issues being discussed that look like 4.4-rc
  regressions.  Hopefully I can get those stabilized soon, but these are
  ready at any rate:

   - A little bit of a last-minute change for the device tree "fixed
     partition" binding.  This is needed because we might want to reuse
     the 'partitions' subnode for other sorts of partitioning
     descriptions -- e.g., for describing which on-flash partition
     format(s) might be used on the system.

   - Also tone down a warning message, since it is probably going to
     show up on a lot of systems where it should just be ignored"

* tag 'for-linus-20151217' of git://git.infradead.org/linux-mtd:
  doc: dt: mtd: partitions: add compatible property to "partitions" node
  mtd: ofpart: don't complain about missing 'partitions' node too loudly

Commit 8520f380 ("USB: change hub initialization sleeps to
delayed_work") changed the hub_activate() routine to make part of it
run in a workqueue.  However, the commit failed to take a reference to
the usb_hub structure or to lock the hub interface while doing so.  As
a result, if a hub is plugged in and quickly unplugged before the work
routine can run, the routine will try to access memory that has been
deallocated.  Or, if the hub is unplugged while the routine is
running, the memory may be deallocated while it is in active use.

This patch fixes the problem by taking a reference to the usb_hub at
the start of hub_activate() and releasing it at the end (when the work
is finished), and by locking the hub interface while the work routine
is running.  It also adds a check at the start of the routine to see
if the hub has already been disconnected, in which nothing should be
done.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Alexandru Cornea <alexandru.cornea@intel.com>
Tested-by: Alexandru Cornea <alexandru.cornea@intel.com>
Fixes: 8520f380 ("USB: change hub initialization sleeps to delayed_work")
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The code expects the loop to end with "retries" set to zero but, because
it is a post-op, it will end set to -1.  I have fixed this by moving the
decrement inside the loop.

Fixes: 014aa2a3 ('USB: ipaq: minor ipaq_open() cleanup.')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Driver requested device firmware version string during probe using
only 24 byte long buffer. That buffer is too small for newer firmware
versions, which causes device firmware hang - device stops responding
to any commands after that. Increase buffer size to 128 which should
be enough for any current and future version strings.

Link: https://github.com/airspy/host/issues/27

Cc: <stable@vger.kernel.org> # 3.17+
Reported-by: Benjamin Vernoux <bvernoux@gmail.com>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

Used Avago MGA-81563 RF amplifier could be destroyed pretty easily
with too strong signal or transmitting to bad antenna.
Add module parameter 'enable_rf_gain_ctrl' which allows enabling
RF gain control - otherwise, default without the module parameter,
RF gain control is set to 'grabbed' state which prevents setting
value to the control.
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/usb/hackrf/hackrf.c:1533 hackrf_probe()
error: we previously assumed 'dev' could be null (see line 1366)
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

This patch broke ivtv logic, as reported at
 https://bugzilla.redhat.com/show_bug.cgi?id=1278942

This reverts commit 09290cc8.

Cc: stable@vger.kernel.org # for v4.1 and upper
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>