When there isn't enough vring descriptor for adding to vq,
blk-mq will be put as stopped state until some of pending
descriptors are completed & freed.

Unfortunately, the vq's interrupt may come just before
blk-mq's BLK_MQ_S_STOPPED flag is set, so the blk-mq will
still be kept as stopped even though lots of descriptors
are completed and freed in the interrupt handler. The worst
case is that all pending descriptors are freed in the
interrupt handler, and the queue is kept as stopped forever.

This patch fixes the problem by starting/stopping blk-mq
with holding vq_lock.

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>

Conflicts:
	drivers/block/virtio_blk.c

Pull media fixes from Mauro Carvalho Chehab:
 "Most of the changes are drivers fixes (rtl28xuu, fc2580, ov7670,
  davinci, gspca, s5p-fimc and s5c73m3).

  There is also a compat32 fix and one infoleak fixup at the media
  controller"

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  [media] V4L2: fix VIDIOC_CREATE_BUFS in 64- / 32-bit compatibility mode
  [media] V4L2: ov7670: fix a wrong index, potentially Oopsing the kernel from user-space
  [media] media-device: fix infoleak in ioctl media_enum_entities()
  [media] fc2580: fix tuning failure on 32-bit arch
  [media] Prefer gspca_sonixb over sn9c102 for all devices
  [media] media: davinci: vpfe: make sure all the buffers unmapped and released
  [media] staging: media: davinci: vpfe: make sure all the buffers are released
  [media] media: davinci: vpbe_display: fix releasing of active buffers
  [media] media: davinci: vpif_display: fix releasing of active buffers
  [media] media: davinci: vpif_capture: fix releasing of active buffers
  [media] s5p-fimc: Fix YUV422P depth
  [media] s5c73m3: Add missing rename of v4l2_of_get_next_endpoint() function
  [media] rtl28xxu: silence error log about disabled rtl2832_sdr module
  [media] rtl28xxu: do not hard depend on staging SDR module

Pull staging driver fixes from Greg KH:
 "Here are five staging driver fixes for 3.15-rc6 that resolve some
  reported issues.  They are for the imx and rtl8723au drivers"

* tag 'staging-3.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: rtl8723au: Do not reset wdev->iftype in netdev_close()
  staging: rtl8723au: Use correct pipe type for USB interrupts
  imx-drm: imx-tve: correct DDC property name to 'ddc-i2c-bus'
  imx-drm: imx-drm-core: skip components whose parent device is disabled
  imx-drm: imx-drm-core: fix imx_drm_encoder_get_mux_id

Merge tag 'driver-core-3.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are two driver core (well, sysfs) fixes for 3.15-rc6 that resolve
  some reported issues and a regression from 3.13"

* tag 'driver-core-3.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  sysfs: make sure read buffer is zeroed
  kernfs, sysfs, cgroup: restrict extra perm check on open to sysfs

Pull PCI fixes from Bjorn Helgaas:
 "These are fixes for an SHPCHP hotplug regression, a "wait for pending
  transaction" problem (used in device reset paths), and an email
  address update.

  PCI device hotplug:
    - Fix SHPCHP bus speed mismatch issue (Marcel Apfelbaum)

  Miscellaneous:
    - Fix pci_wait_for_pending_transaction() (Gavin Shan)
    - Update email address (Ben Hutchings)"

* tag 'pci-v3.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: Wrong register used to check pending traffic
  PCI: shpchp: Check bridge's secondary (not primary) bus speed
  PCI: Update my email address

Pull /dev/random fix from Ted Ts'o:
 "This fixes a BUG_ON-causing regression that was introduced during the
  last merge window"

* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: fix BUG_ON caused by accounting simplification

Pull clock framework fixes from Mike Turquette:
 "Clock framework and driver fixes, all of which fix user-visible
  regressions.

  As usual most fixes are for platform-specific clock drivers, but there
  are also two fixes to the clk core after recent changes to the way
  that clock unregistration is handled"

* tag 'clk-fixes-for-linus' of git://git.linaro.org/people/mike.turquette/linux:
  clk: tegra: Fix wrong value written to PLLE_AUX
  clk: shmobile: clk-mstp: change to using clock-indices
  clk: Fix slab corruption in clk_unregister()
  clk: Fix double free due to devm_clk_register()
  clk: socfpga: fix clock driver for 3.15
  clk: divider: Fix best div calculation for power-of-two and table dividers
  clk: bcm281xx: don't use unnamed structs or unions

Pull spi fixes from Mark Brown:
 "A few core fixes around outlying cases here, nothing that should
  affect most users but useful fixes.  The diffstat is rather larger
  than one might hope due some simple code motion in the fix for
  !CONFIG_DMA, the actual meaningful change is much smaller.

   - Fix handling of unsupported dual and quad mode support on slave
     registration so that drivers that can degrade gracefully do so,
     preventing regressions for drivers this is added.
   - Fix build in !CONFIG_DMA cases following addition of generic DMA
     mapping support.
   - Fix error handling for queue creation which due to wider kernel
     changes can be triggered more easily.
   - A couple of driver specific fixes"

* tag 'spi-v3.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi/pxa2xx: Prevent DMA from transferring too many bytes
  spi: core: Don't destroy master queue if we fail to create it
  spi: qup: Fix return value checking for pm_runtime_get_sync()
  spi: core: Protect DMA code by #ifdef CONFIG_HAS_DMA
  spi: core: Ignore unsupported Dual/Quad Transfer Mode bits

Pull GPIO fixes from Linus Walleij:
 - fix a null pointer bug in the ICH6 chipset driver
 - fix device tree registration for the mcp23s08 driver

* tag 'gpio-v3.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: mcp23s08: Bug fix of SPI device tree registration.
  gpio: ich: set regs and reglen for i3100 and ich6 chipset

Pull more cgroup fixes from Tejun Heo:
 "Three more patches to fix cgroup_freezer breakage due to the recent
  cgroup internal locking changes - an operation cgroup_freezer was
  using now requires sleepable context and cgroup_freezer was invoking
  that while holding a spin lock.  cgroup_freezer was using an overly
  elaborate hierarchical locking scheme.

  While it's possible to convert the hierarchical spinlocks directly to
  mutexes, this patch simplifies the overall locking so that it uses a
  global mutex.  This has the added benefit of avoiding iterating
  potentially huge number of tasks under a spinlock.  While the patch is
  on the larger side in the devel cycle, the changes made are mostly
  straight-forward and the locking logic is a lot simpler afterwards"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix rcu_read_lock() leak in update_if_frozen()
  cgroup_freezer: replace freezer->lock with freezer_mutex
  cgroup: introduce task_css_is_root()

Pull libata fixes from Tejun Heo:
 "Mostly device-specific fixes.  The only thing which isn't is the fix
  for zpodd oops-on-detach bug"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ahci: imx: PLL clock needs 100us to settle down
  ata: pata_at91 only works on sam9
  libata: clean up ZPODD when a port is detached
  ahci: imx: software workaround for phy reset issue in resume
  ahci: imx: add namespace for register enums
  ahci: disable DEVSLP for Intel Valleyview

Pull crypto fixes from Herbert Xu:
 "This fixes a NULL pointer dereference on allocation failure in caam,
  as well as a regression in the ctr mode on s390 that was added with
  the recent concurrency fixes"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: s390 - fix aes,des ctr mode concurrency finding.
  crypto: caam - add allocation failure handling in SPRINTFCAT macro

Pull scsi target fixes from Nicholas Bellinger:
 "This series include:

   - Close race between iser-target network portal shutdown + accepting
     new connection logins (sagi)
   - Fix free-after-use regression in tcm_fc post conversion to
     percpu-ida pre-allocation (nab)
   - Explicitly disable Immediate + Unsolicited Data for iser-target
     connections when T10-PI is enabled (sagi + nab)
   - Allow pi_prot_type + emulate_write_cache attributes to be set to
     zero regardless of backend support (andy)
   - memory leak fix (mikulas)"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target: fix memory leak on XCOPY
  target: Don't allow setting WC emulation if device doesn't support
  iscsi-target: Disable Immediate + Unsolicited Data with ISER Protection
  tcm_fc: Fix free-after-use regression in ft_free_cmd
  iscsi-target: Change BUG_ON to REJECT in iscsit_process_nop_out
  Target/iscsi,iser: Avoid accepting transport connections during stop stage
  Target/iser: Fix iscsit_accept_np and rdma_cm racy flow
  Target/iser: Fix wrong connection requests list addition
  target: Allow non-supporting backends to set pi_prot_type to 0

Pull i2c fixes from Wolfram Sang:
 "Some I2C bugfixes for 3.15.  Typical stuff, I'd say"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: rcar: bail out on zero length transfers
  i2c: qup: Fix pm_runtime_get_sync usage
  i2c: s3c2410: resume race fix
  i2c: nomadik: Don't use IS_ERR for devm_ioremap
  i2c: designware: Mask all interrupts during i2c controller enable

Pull ACPI and power management fixes from Rafael Wysocki:
 "Still fixing regressions (partly by reverting commits that broke
  things for people), fixing other stable-candidate bugs and adding some
  blacklist entries for ACPI video and _OSI.

  Two ACPICA regression fixes (one recent and one for a 3.14 commit), a
  fix for an ACPI-related regression in TPM (introduced in 3.14), a
  revert of the ACPI AC driver conversion in 3.13 that went wrong for an
  unknown reason, two reverts of commits that attempted to remove an old
  user space interface in /proc and broke some utilities, in 3.13 too, a
  fix for a CPU hotplug bug in the ACPI processor driver (stable
  material), two (stable candidate) fixes for intel_pstate and a few new
  blacklist entries, mostly for systems that shipped with Windows 8.

  Specifics:

   - ACPICA fix for a stale pointer access introduced by a recent commit
     in the XSDT validation code from Lv Zheng.

   - ACPICA fix for the default value of the command line switch to
     favor 32-bit FADT addresses (in case there's a conflict between a
     64-bit and a 32-bit address).  The previous default was that the
     32-bit version would take precedence and we tried to change it to
     the other way around and it didn't work.  From Lv Zheng.

   - A TPM commit related to ACPI _DSM in 3.14 caused the driver to
     refuse to load if a specific _DSM was missing and that broke resume
     from system suspend on Chromebooks that require the TPM hardware to
     be restored to a working state during resume by the OS.  Restore
     the old behavior to load the driver if the _DSM in question is not
     present, but prevent it from using the feature the _DSM is for.

   - ACPI AC driver conversion in 3.13 broke thermal management on at
     least one machine and has to be reverted.  From Guenter Roeck.

   - Two reverts of 3.13 commits that attempted to remove the old ACPI
     battery interface in /proc, but turned out to break some utilities
     still using that interface.  From Lan Tianyu.

   - ACPI processor driver fix to prevent acpi_processor_add() from
     modifying the CPU device's .offline field which leads to breakage
     if the initial online of the CPU fails.  From Igor Mammedov.

   - Two intel_pstate fixes, one to take a BayTrail documentation update
     into account and one to avoid forcing the maximum P-state on init
     which causes CPU PM trouble on systems with P-states coordination
     when one of the CPU cores is initialized after an offline/online
     cycle triggered by user space.  Both stable candidates, from Dirk
     Brandewie.

   - Fix for the ACPI video DMI blacklist entry for Dell Inspiron 7520
     from Aaron Lu.

   - Two new ACPI video blacklist entries for machines shipping with
     Win8 that need to use native backlight so that it can be controlled
     in a usual way (which doesn't work otherwise due bugs in the ACPI
     tables) from Hans de Goede.

   - Two ACPI _OSI quirks for systems that need them to work correctly
     with Linux from Edward Lin and Hans de Goede"

* tag 'pm+acpi-3.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / video: Revert native brightness quirk for ThinkPad T530
  intel_pstate: remove setting P state to MAX on init
  ACPICA: Tables: Restore old behavor to favor 32-bit FADT addresses.
  ACPI / video: correct DMI tag for Dell Inspiron 7520
  intel_pstate: Set turbo VID for BayTrail
  ACPI / TPM: Fix resume regression on Chromebooks
  ACPI / proc: Do not say when /proc interfaces will be deleted in Kconfig
  ACPI / processor: do not mark present at boot but not onlined CPU as onlined
  ACPI: Revert "ACPI / AC: convert ACPI ac driver to platform bus"
  ACPI / blacklist: Add dmi_enable_osi_linux quirk for Asus EEE PC 1015PX
  ACPI: blacklist win8 OSI for Dell Inspiron 7737
  ACPI / video: Add use_native_backlight quirks for more systems
  ACPI: Revert "ACPI / Battery: Remove battery's proc directory"
  ACPI: Revert "ACPI: Remove CONFIG_ACPI_PROCFS_POWER and cm_sbsc.c"
  ACPICA: Tables: Fix invalid pointer accesses in acpi_tb_parse_root_table().

Pull device mapper fixes from Mike Snitzer:
 "A dm-crypt fix for a cpu hotplug crash that switches from using
  per-cpu data to a mempool allocation (which offers allocation with cpu
  locality, and there is no inter-cpu communication on slab allocation).

  A couple dm-thinp stable fixes to address "out-of-data-space" issues.

  A dm-multipath fix for a LOCKDEP warning introduced in 3.15-rc1"

* tag 'dm-3.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm mpath: fix lock order inconsistency in multipath_ioctl
  dm thin: add timeout to stop out-of-data-space mode holding IO forever
  dm thin: allow metadata commit if pool is in PM_OUT_OF_DATA_SPACE mode
  dm crypt: fix cpu hotplug crash by removing per-cpu structure

Pull device tree fixes from Grant Likely:
 "Drivercore bugfixes for v3.15

  This branch contains bug fixes important to get into v3.15.  There is
  a fix for modifying properties seen during early boot, a fix for an
  incorrect prototype when CONFIG_OF=n, and a couple of corrections to
  device tree memory nodes on a few platforms"

* tag 'dt-for-linus' of git://git.secretlab.ca/git/linux:
  mips: dts: Fix missing device_type="memory" property in memory nodes
  arm: dts: Fix missing device_type="memory" for ste-ccu8540
  of: fix CONFIG_OF=n prototype of of_node_full_name()
  of: make of_update_property() usable earlier in the boot process

Pull sound fixes from Takashi Iwai:
 "Unfortunately this update became bigger than previous pull requests,
  which is almost a pattern in rc5-6.  But, the only obvious big changes
  are for the new Intel DSP ASoC drivers, so the impact must be fairly
  limited.

  Other than that, usual small fixes in various fields: HD-audio, ASoC
  core and ASoC fsl and codec drivers"

* tag 'sound-3.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (26 commits)
  ALSA: sb_mixer: missing return statement
  ASoC: wm8962: Update register CLASS_D_CONTROL_1 to be non-volatile
  ASoC: Intel: Fix Baytrail SST DSP firmware loading
  ALSA: hda - mask buggy stream DMA0 for Broadwell display controller
  ALSA: hda - Add new GPU codec ID to snd-hda
  ASoC: fsl_esai: Set PCRC and PRRC registers at the end of hw_params()
  ASoC: fsl_esai: Only bypass sck_div for EXTAL source
  ASoC: fsl_esai: Fix incorrect condition within ratio range check for FP
  ASoC: dapm: Fix SUSPEND -> OFF bias sequence
  ASoC: dapm: Skip CODEC<->CODEC links in connect_dai_link_widgets()
  ASoC: pcm: Fix incorrect condition check for case SNDRV_PCM_TRIGGER_SUSPEND
  ALSA: hda - add headset mic detect quirks for three Dell laptops
  ASoC: Update Cirrus Logic CODEC maintainers.
  ASoC: Intel: Fix block offset calculations.
  ASoC: Intel: Fix check for pdata usage before dereference.
  ASoC: Intel: Fix stream position pointer.
  ASoC: Intel: Fix allow hw_params to be called more than once.
  ASoC: Intel: Fix Audio DSP usage when IOMMU is enabled.
  ASoC: Intel: Fix Haswell/Broadwell DSP page table creation.
  ASoC: Intel: Fix allocated block list usage when adding blocks.
  ...

Pull MIPS fixes from Ralf Baechle:
 "MIPS fixes for various loose ends:

   - Fix workarounds for R4000 erratum.
   - Patch up DEC, Siemens-Nixdorf and Loongson hardware support.
   - Wire up renameat2 syscall.
   - Delete unused file - it was causing false warnings from maintenance
     scripts.
   - Revert a patch because it's functionality is now implemented twice
     which causes superfluous /proc/cpuinfo output.
   - Fix a microMIPS regression"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: mm: Fix broken microMIPS kernel regression.
  MIPS: Add new AUDIT_ARCH token for the N32 ABI on MIPS64
  MIPS: Wire up renameat2 syscall.
  MIPS: inst.h: Rename BITFIELD_FIELD to __BITFIELD_FIELD.
  MIPS: Remove file missed when removing rm9k support a while ago.
  MIPS/loongson2_cpufreq: Fix CPU clock rate setting
  MIPS: Loongson: No need to select GENERIC_HARDIRQS_NO__DO_IRQ
  MIPS: csum_partial.S CPU_DADDI_WORKAROUNDS bug fix
  MIPS: __strncpy_from_user_asm CPU_DADDI_WORKAROUNDS bug fix
  MIPS: __delay CPU_DADDI_WORKAROUNDS bug fix
  MIPS: DEC/SNI: O32 wrapper stack switching fixes
  MIPS: DEC: Bus error handler <asm/cpu-type.h> fixes
  MAINTAINERS: TURBOchannel: Update entry
  Revert "MIPS: MT: proc: Add support for printing VPE and TC ids"

Pull parisc fixes from Helge Deller:
 "There are two patches in here:

  The first patch greatly improves latency and corrects the memory
  ordering in our light-weight atomic locking syscall.

  The second patch ratelimits printing of userspace segfaults in the
  same way as it's done on other platforms.  This fixes a possible DOS
  on parisc since it prevents the syslog to grow too fast.  For example,
  when the debian acl2 package was built on our debian buildd servers,
  this package produced lots of gigabytes in syslog in very short time
  and thus filled our harddisks, which then turned the server nearly
  completely unaccessible and unresponsive"

* 'parisc-3.15-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Improve LWS-CAS performance
  parisc: ratelimit userspace segfault printing

Pull two arm64 fixes from Catalin Marinas:
 - arm64 migrate_irqs() fix following commit ffde1de6 (irqchip: Gic:
   Support forced affinity setting)
 - fix arm64 pud_huge() to return 0 when only 2 levels page tables are
   used (__PAGETABLE_PMD_FOLDED defined and pmd_huge already covers
   block entries at the first level), otherwise KVM gets confused

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: fix pud_huge() for 2-level pagetables
  arm64: use cpu_online_mask when using forced irq_set_affinity

Pull Metag architecture and related fixes from James Hogan:
 "Mostly fixes for metag and parisc relating to upgrowing stacks.

   - Fix missing compiler barriers in metag memory barriers.
   - Fix BUG_ON on metag when RLIMIT_STACK hard limit is increased
     beyond safe value.
   - Make maximum stack size configurable.  This reduces the default
     user stack size back to 80MB (especially on parisc after their
     removal of _STK_LIM_MAX override).  This only affects metag and
     parisc.
   - Remove metag _STK_LIM_MAX override to match other arches and follow
     parisc, now that it is safe to do so (due to the BUG_ON fix
     mentioned above).
   - Finally now that both metag and parisc _STK_LIM_MAX overrides have
     been removed, it makes sense to remove _STK_LIM_MAX altogether"

* tag 'metag-for-v3.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag:
  asm-generic: remove _STK_LIM_MAX
  metag: Remove _STK_LIM_MAX override
  parisc,metag: Do not hardcode maximum userspace stack size
  metag: Reduce maximum stack size to 256MB
  metag: fix memory barriers

Pull drm/intel fixes from Dave Airlie:
 "Just some intel fixes.

  I have some radeon ones but I need to get some patches dropped from
  the pull req"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: Increase WM memory latency values on SNB
  drm/i915: restore backlight precision when converting from ACPI
  drm/i915: Use the first mode if there is no preferred mode in the EDID
  drm/i915/dp: force eDP lane count to max available lanes on BDW
  drm/i915/vlv: reset VLV media force wake request register
  drm/i915/SDVO: For sysfs link put directory and target in correct order
  drm/i915: use lane count and link rate from VBT as minimums for eDP
  drm/i915: clean up VBT eDP link param decoding
  drm/i915: consider the source max DP lane count too

Pull x86 fixes from Peter Anvin.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86-64, modify_ldt: Make support for 16-bit segments a runtime option
  x86, mm, hugetlb: Add missing TLB page invalidation for hugetlb_cow()
  x86, rdrand: When nordrand is specified, disable RDSEED as well

Pull timer fix from Thomas Gleixner:
 "A single bug fix for a long standing issue:

   - Updating the expiry value of a relative timer _after_ letting the
     idle logic select a target cpu for the timer based on its stale
     expiry value is outright stupid.  Thanks to Viresh for spotting the
     brainfart"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Set expiry time before switch_hrtimer_base()

Pull irq fixes from Thomas Gleixner:
 "Two small updates from the irq departement:

   - Provide missing inline stub for a SMP only function

   - Add sub-maintainer for the drivers/irqchip/ part of the irq
     subsystem.  YAY!"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  MAINTAINERS: Add co-maintainer for drivers/irqchip
  genirq: Provide irq_force_affinity fallback for non-SMP

13c589d5 ("sysfs: use seq_file when reading regular files")
switched sysfs from custom read implementation to seq_file to enable
later transition to kernfs.  After the change, the buffer passed to
->show() is acquired through seq_get_buf(); unfortunately, this
introduces a subtle behavior change.  Before the commit, the buffer
passed to ->show() was always zero as it was allocated using
get_zeroed_page().  Because seq_file doesn't clear buffers on
allocation and neither does seq_get_buf(), after the commit, depending
on the behavior of ->show(), we may end up exposing uninitialized data
to userland thus possibly altering userland visible behavior and
leaking information.

Fix it by explicitly clearing the buffer.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Ron <ron@debian.org>
Fixes: 13c589d5 ("sysfs: use seq_file when reading regular files")
Cc: stable <stable@vger.kernel.org> # 3.13+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Intel fixes for regressions, black screens and hangs, for 3.15.

* tag 'drm-intel-fixes-2014-05-16' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Increase WM memory latency values on SNB
  drm/i915: restore backlight precision when converting from ACPI
  drm/i915: Use the first mode if there is no preferred mode in the EDID
  drm/i915/dp: force eDP lane count to max available lanes on BDW
  drm/i915/vlv: reset VLV media force wake request register
  drm/i915/SDVO: For sysfs link put directory and target in correct order
  drm/i915: use lane count and link rate from VBT as minimums for eDP
  drm/i915: clean up VBT eDP link param decoding
  drm/i915: consider the source max DP lane count too

The commit e783c51c (ahci: imx: software workaround for phy reset issue
in resume) calls imx_sata_phy_reset() to reset phy immediately after
SATA MPLL is enabled.  It seems working fine mostly, but fails in some
case as below.

...
ahci-imx 2200000.sata: failed to reset phy: -110
ahci-imx: probe of 2200000.sata failed with error -110

After talking to the designer, we learnt that when enabling i.MX6Q SATA
MPLL, we need to wait 100us for it to settle down for safety.  Add this
required delay to fix above failure.
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

The incorrect register offset is passed to pci_wait_for_pending(), which is
caused by commit 157e876f ("PCI: Add pci_wait_for_pending() (refactor
pci_wait_for_pending_transaction())").

Fixes: 157e876f ("PCI: Add pci_wait_for_pending() (refactor pci_wait_for_pending_transaction())
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Williamson <alex.williamson@gmail.com>
CC: stable@vger.kernel.org	# v3.14+

On each processed XCOPY command, two "kmalloc-512" memory objects are
leaked. These represent two allocations of struct xcopy_pt_cmd in
target_core_xcopy.c.

The reason for the memory leak is that the cmd_kref field is not
initialized (thus, it is zero because the allocations were done with
kzalloc). When we decrement zero kref in target_put_sess_cmd, the result
is not zero, thus target_release_cmd_kref is not called.

This patch fixes the bug by moving kref initialization from
target_get_sess_cmd to transport_init_se_cmd (this function is called from
target_core_xcopy.c, so it will correctly initialize cmd_kref). It can be
easily verified that all code that calls target_get_sess_cmd also calls
transport_init_se_cmd earlier, thus moving kref_init shouldn't introduce
any new problems.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org	# 3.12+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Commit ee1de406 ("random: simplify accounting logic") simplified
things too much, in that it allows the following to trigger an
overflow that results in a BUG_ON crash:

dd if=/dev/urandom of=/dev/zero bs=67108707 count=1

Thanks to Peter Zihlstra for discovering the crash, and Hannes
Frederic for analyizing the root cause.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Greg Price <price@mit.edu>

The value written to PLLE_AUX was incorrect due to a wrong variable
being used. Without this fix SATA does not work.

Cc: stable@vger.kernel.org
Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Tested-by: Mikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
[mturquette@linaro.org: improved changelog]

wdev->ifdev should be set by .change_virtual_intf(). This solves the
problem of WARN() messages on module unload.
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

* acpi-video:
  ACPI / video: Revert native brightness quirk for ThinkPad T530

Seems it helps some users, but causes issues for other users:
https://bugzilla.redhat.com/show_bug.cgi?id=1089545

So lets drop it for now until we've figured out a better fix.

Fixes: 43d94902 (ACPI / video: Add use_native_backlight quirks for more systems)
References: https://bugzilla.redhat.com/show_bug.cgi?id=1089545
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Use a correct pipe type when filling un interrupt urbs. This should
finally take care of the WARN() messages on the console when USB urbs
are submitted.
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The following happens when trying to run a kvm guest on a kernel
configured for 64k pages. This doesn't happen with 4k pages:

  BUG: failure at include/linux/mm.h:297/put_page_testzero()!
  Kernel panic - not syncing: BUG!
  CPU: 2 PID: 4228 Comm: qemu-system-aar Tainted: GF            3.13.0-0.rc7.31.sa2.k32v1.aarch64.debug #1
  Call trace:
  [<fffffe0000096034>] dump_backtrace+0x0/0x16c
  [<fffffe00000961b4>] show_stack+0x14/0x1c
  [<fffffe000066e648>] dump_stack+0x84/0xb0
  [<fffffe0000668678>] panic+0xf4/0x220
  [<fffffe000018ec78>] free_reserved_area+0x0/0x110
  [<fffffe000018edd8>] free_pages+0x50/0x88
  [<fffffe00000a759c>] kvm_free_stage2_pgd+0x30/0x40
  [<fffffe00000a5354>] kvm_arch_destroy_vm+0x18/0x44
  [<fffffe00000a1854>] kvm_put_kvm+0xf0/0x184
  [<fffffe00000a1938>] kvm_vm_release+0x10/0x1c
  [<fffffe00001edc1c>] __fput+0xb0/0x288
  [<fffffe00001ede4c>] ____fput+0xc/0x14
  [<fffffe00000d5a2c>] task_work_run+0xa8/0x11c
  [<fffffe0000095c14>] do_notify_resume+0x54/0x58

In arch/arm/kvm/mmu.c:unmap_range(), we end up doing an extra put_page()
on the stage2 pgd which leads to the BUG in put_page_testzero(). This
happens because a pud_huge() test in unmap_range() returns true when it
should always be false with 2-level pages tables used by 64k pages.
This patch removes support for huge puds if 2-level pagetables are
being used.
Signed-off-by: Mark Salter <msalter@redhat.com>
[catalin.marinas@arm.com: removed #ifndef around PUD_SIZE check]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org> # v3.11+

A few platforms lack a 'device_type = "memory"' for their memory
nodes, relying on an old ppc quirk in order to discover its memory.
Add the missing data so that all parsing code can find memory nodes
correctly.
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Acked-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>

The current .dts for ste-ccu8540 lacks a 'device_type = "memory"' for
its memory node, relying on an old ppc quirk in order to discover its
memory. Fix the data so that all parsing code can handle it correctly.
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: devicetree@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>