To avoid duplicating this double filemap_fdatawrite_range() call for
inodes with async extents (compressed writes) so often.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

For compressed writes, after doing the first filemap_fdatawrite_range() we
don't get the pages tagged for writeback immediately. Instead we create
a workqueue task, which is run by other kthread, and keep the pages locked.
That other kthread compresses data, creates the respective ordered extent/s,
tags the pages for writeback and unlocks them. Therefore we need a second
call to filemap_fdatawrite_range() if we have compressed writes, as this
second call will wait for the pages to become unlocked, then see they became
tagged for writeback and finally wait for the writeback to finish.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Its return value is useless, its single caller ignores it and can't do
anything with it anyway, since it's a workqueue task and not the task
calling filemap_fdatawrite_range (writepages) nor filemap_fdatawait_range().
Failure is communicated to such functions via start and end of writeback
with the respective pages tagged with an error and AS_EIO flag set in the
inode's imapping.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Steps to reproduce:
 # mkfs.btrfs -f /dev/sdb
 # mount -t btrfs /dev/sdb /mnt -o compress=lzo
 # dd if=/dev/zero of=/mnt/data bs=$((33*4096)) count=1

after previous steps, inode will be detected as bad compression ratio,
and NOCOMPRESS flag will be set for that inode.

Reason is that compress have a max limit pages every time(128K), if a
132k write in, it will be splitted into two write(128k+4k), this bug
is a leftover for commit 68bb462d(Btrfs: don't compress for a small write)

Fix this problem by checking every time before compression, if it is a
small write(<=blocksize), we bail out and fall into nocompression directly.
Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>

Our compressed bio write end callback was essentially ignoring the error
parameter. When a write error happens, it must pass a value of 0 to the
inode's write_page_end_io_hook callback, SetPageError on the respective
pages and set AS_EIO in the inode's mapping flags, so that a call to
filemap_fdatawait_range() / filemap_fdatawait() can find out that errors
happened (we surely don't want silent failures on fsync for example).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Its return value is completely ignored by its single caller and it's
useless anyway, since errors are indicated through SetPageError and
the bit AS_EIO set in the flags of the inode's mapping. The caller
can't do anything with the value, as it's invoked from a workqueue
task and not by the task calling filemap_fdatawrite_range (which calls
the writepages address space callback, which in turn calls the inode's
fill_delalloc callback).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

If we had an error when processing one of the async extents from our list,
we were not processing the remaining async extents, meaning we would leak
those async_extent structs, never release the pages with the compressed
data and never unlock and clear the dirty flag from the inode's pages (those
that correspond to the uncompressed content).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

In inode.c:submit_compressed_extents(), if we fail before calling
btrfs_submit_compressed_write(), or when that function fails, we
were freeing the async_extent structure without releasing its pages
and freeing the pages array.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

In inode.c:submit_compressed_extents(), before calling btrfs_submit_compressed_write()
we start writeback for all pages, clear their dirty flag, unlock them, etc, but if
btrfs_submit_compressed_write() fails (at the moment it can only fail with -ENOMEM),
we never end the writeback on the pages, so any filemap_fdatawait_range() call will
hang forever. We were also not calling the writepage end io hook, which means the
corresponding ordered extent will never complete and all its waiters will block
forever, such as a full fsync (via btrfs_wait_ordered_range()).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

If we fail in submit_compressed_extents() before calling btrfs_submit_compressed_write(),
we start and end the writeback for the pages (clear their dirty flag, unlock them, etc)
but we don't tag the pages, nor the inode's mapping, with an error. This makes it
impossible for a caller of filemap_fdatawait_range() (fsync, or transaction commit
for e.g.) know that there was an error.

Note that the return value of submit_compressed_extents() is useless, as that function
is executed by a workqueue task and not directly by the fill_delalloc callback. This
means the writepage/s callbacks of the inode's address space operations don't get that
return value.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

Pull ARM SoC fixes from Olof Johansson:
 "Another small set of fixes:

   - some DT compatible typo fixes
   - irq setup fix dealing with irq storms on orion
   - i2c quirk generalization for mvebu
   - a handful of smaller fixes for OMAP
   - a couple of added file patterns for OMAP entries in MAINTAINERS"

* tag 'armsoc-for-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: at91/dt: Fix sama5d3x typos
  pinctrl: dra: dt-bindings: Fix output pull up/down
  MAINTAINERS: Update entry for omap related .dts files to cover new SoCs
  MAINTAINERS: add more files under OMAP SUPPORT
  ARM: dts: AM437x-SK-EVM: Fix DCDC3 voltage
  ARM: dts: AM437x-GP-EVM: Fix DCDC3 voltage
  ARM: dts: AM43x-EPOS-EVM: Fix DCDC3 voltage
  ARM: dts: am335x-evm: Fix 5th NAND partition's name
  ARM: orion: Fix for certain sequence of request_irq can cause irq storm
  ARM: mvebu: armada xp: Generalize use of i2c quirk

Pull sparc fixes from David Miller:

 1) Fix NULL oops in Schizo PCI controller error handler.

 2) Fix race between xchg and other operations on 32-bit sparc, from
    Andreas Larsson.

 3) swab*() helpers need a dummy memory input operand to show data flow
    on 64-bit sparc.

 4) Fix RCU warnings due to missing irq_{enter,exit}() around
    generic_smp_call_function*() calls.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Fix constraints on swab helpers.
  sparc32: Implement xchg and atomic_xchg using ATOMIC_HASH locks
  sparc64: Do irq_{enter,exit}() around generic_smp_call_function*().
  sparc64: Fix crashes in schizo_pcierr_intr_other().

Pull md bugfix from Neil Brown:
 "One fix for md for 3.18.

  This fixes a regression introduced in 3.13"

* tag 'md/3.18-fix' of git://neil.brown.name/md:
  md: Always set RECOVERY_NEEDED when clearing RECOVERY_FROZEN

Some DT files had a typo with a missing "5" in sama5d3x first compatible string.
Signed-off-by: Peter Rosin <peda@axentia.se>
[nicolas.ferre@atmel.com: modify commit log]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge tag 'omap-fixes-against-v3.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Merge "omap fixes against v3.18-rc4" from Tony Lindgren:

Few omap fixes for hangs and wrong pinctrl defines, and update
MAINTAINERS file to avoid missing PMIC and SoC related patches:

- Fix random hangs on am437x because of incorrect default
  value for the DDR regulator

- Fix wrong partition name for NAND on am335x-evm

- Fix wrong pinctrl defines for dra7xx

- Update maintainers entries for PMICs and SoCs

* tag 'omap-fixes-against-v3.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  pinctrl: dra: dt-bindings: Fix output pull up/down
  MAINTAINERS: Update entry for omap related .dts files to cover new SoCs
  MAINTAINERS: add more files under OMAP SUPPORT
  ARM: dts: AM437x-SK-EVM: Fix DCDC3 voltage
  ARM: dts: AM437x-GP-EVM: Fix DCDC3 voltage
  ARM: dts: AM43x-EPOS-EVM: Fix DCDC3 voltage
  ARM: dts: am335x-evm: Fix 5th NAND partition's name
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge "mvebu fixes for v3.18" from Jason Cooper:

 - Armada XP
    - Generalize i2c quirk

 - orion
    - Fix irq storm caused by specific sequence of request_irq

* tag 'mvebu-fixes-3.18' of git://git.infradead.org/linux-mvebu:
  ARM: orion: Fix for certain sequence of request_irq can cause irq storm
  ARM: mvebu: armada xp: Generalize use of i2c quirk

md_check_recovery will skip any recovery and also clear
MD_RECOVERY_NEEDED if MD_RECOVERY_FROZEN is set.
So when we clear _FROZEN, we must set _NEEDED and ensure that
md_check_recovery gets run.
Otherwise we could miss out on something that is needed.

In particular, this can make it impossible to remove a
failed device from an array is the  'recovery-needed' processing
didn't happen.
Suitable for stable kernels since 3.13.

Cc: stable@vger.kernel.org (3.13+)
Reported-and-tested-by: Joe Lawrence <joe.lawrence@stratus.com>
Fixes: 30b8feb7Signed-off-by: NeilBrown <neilb@suse.de>

We are reading the memory location, so we have to have a memory
constraint in there purely for the sake of showing the data flow
to the compiler.
Reported-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull SCSI fixes from James Bottomley:
 "This is a set of six fixes and a MAINTAINER update.

  The fixes are two multipath (one in Test Unit Ready handling for the
  path checkers and one in the section of code that sends a start unit
  after failover; both of these were perturbed by the scsi-mq update), a
  CD-ROM door locking fix that was likewise introduced by scsi-mq and
  three driver fixes for a previous code update in cxgb4i, megaraid_sas
  and bnx2fc"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  bnx2fc: fix tgt spinlock locking
  megaraid_sas: fix bug in handling return value of pci_enable_msix_range()
  cxgb4i: send abort_rpl correctly
  cxgbi: add maintainer for cxgb3i/cxgb4i
  scsi: TUR path is down after adapter gets reset with multipath
  scsi: call device handler for failed TUR command
  scsi: only re-lock door after EH on devices that were reset

Pull x86 fixes from Ingo Molnar:
 "Microcode fixes, a Xen fix and a KASLR boot loading fix with certain
  memory layouts"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, microcode, AMD: Fix ucode patch stashing on 32-bit
  x86/core, x86/xen/smp: Use 'die_complete' completion when taking CPU down
  x86, microcode: Fix accessing dis_ucode_ldr on 32-bit
  x86, kaslr: Prevent .bss from overlaping initrd
  x86, microcode, AMD: Fix early ucode loading on 32-bit

Al Viro pointed out that the x86-64 csum_partial_copy_from_user() is
somewhat confused about what it should do on errors, notably it mostly
clears the uncopied end result buffer, but misses that for the initial
alignment case.

All users should check for errors, so it's dubious whether the clearing
is even necessary, and Al also points out that we should probably clean
up the calling conventions, but regardless of any future changes to this
function, the fact that it is inconsistent is just annoying.

So make the __get_user() failure path use the same error exit as all the
other errors do.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Miller <davem@davemloft.net>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull ARM fixes from Russell King:
 "Two fixes this time, one to ensure that the kuser helper option
  depends on MMU as they aren't available for noMMU targets (and if the
  option is selected, we end up oopsing.)

  The second fix plugs a corner case with the decompressor, ensuring
  that the instruction stream can see the relocated code in every case
  on ARMv7 CPUs"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8198/1: make kuser helpers depend on MMU
  ARM: 8191/1: decompressor: ensure I-side picks up relocated code

Pull parisc updates from Helge Deller:
 "Changes include:
   - wire up the bpf syscall
   - remove CONFIG_64BIT usage from some userspace-exported header files
   - use compat functions for msgctl, shmat, shmctl and semtimedop
     syscalls"

* 'parisc-3.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Avoid using CONFIG_64BIT in userspace exported headers
  parisc: Use compat layer for msgctl, shmat, shmctl and semtimedop syscalls
  parisc: Use BUILD_BUG() instead of undefined functions
  parisc: Wire up bpf syscall

Pull power supply updates from Sebastian Reichel:
 "Power supply and reset changes for the v3.18-rc:

   - misc. charger-manager fixes
   - year 2038 fix in ab8500_fg
   - fix error handling of bq2415x_charger"

* tag 'for-v3.18-rc' of git://git.infradead.org/battery-2.6:
  power: charger-manager: Fix accessing invalidated power supply after charger unbind
  power: charger-manager: Fix accessing invalidated power supply after fuel gauge unbind
  power: charger-manager: Avoid recursive thermal get_temp call
  power_supply: Add no_thermal property to prevent recursive get_temp calls
  power: bq2415x_charger: Fix memory leak on DTS parsing error
  power: bq2415x_charger: Properly handle ENODEV from power_supply_get_by_phandle
  power: ab8500_fg.c: use 64-bit time types

Pull drm gixes from Dave Airlie:
 - exynos: infinite loop regressions fixed
 - i915: one regression
 - radeon: one race condition on monitor probing
 - noveau: two regressions
 - tegra: one vblank regression fix

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/tegra: dc: Add missing call to drm_vblank_on()
  drm/nouveau/nv50/disp: Fix modeset on G94
  drm/gk20a/fb: fix setting of large page size bit
  drm/radeon: add locking around atombios scratch space usage
  drm/i915: Fix obj->map_and_fenceable across tiling changes
  drm/exynos: fix possible infinite loop issue
  drm/exynos: g2d: fix null pointer dereference
  drm/exynos: resolve infinite loop issue on non multi-platform
  drm/exynos: resolve infinite loop issue on multi-platform

Sasha Levin reports:
 "gcc5 changes the default standard to c11, which makes kernel build
  unhappy

  Explicitly define the kernel standard to be gnu89 which should keep
  everything working exactly like it was before gcc5"

There are multiple small issues with the new default, but the biggest
issue seems to be that the old - and very useful - GNU extension to
allow a cast in front of an initializer has gone away.

Patch updated by Kirill:
 "I'm pretty sure all gcc versions you can build kernel with supports
  -std=gnu89.  cc-option is redunrant.

  We also need to adjust HOSTCFLAGS otherwise allmodconfig fails for me"

Note by Andrew Pinski:
 "Yes it was reported and both problems relating to this extension has
  been added to gnu99 and gnu11.  Though there are other issues with the
  kernel dealing with extern inline have different semantics between
  gnu89 and gnu99/11"

End result: we may be able to move up to a newer stdc model eventually,
but right now the newer models have some annoying deficiencies, so the
traditional "gnu89" model ends up being the preferred one.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Singed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

   - stable patches to fix NFSv4.x delegation reclaim error paths
   - fix a bug whereby we were advertising NFSv4.1 but using NFSv4.2
     features
   - fix a use-after-free problem with pNFS block layouts
   - fix a memory leak in the pNFS files O_DIRECT code
   - replace an intrusive and Oops-prone performance fix in the NFSv4
     atomic open code with a safer one-line version and revert the two
     original patches"

* tag 'nfs-for-3.18-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  sunrpc: fix sleeping under rcu_read_lock in gss_stringify_acceptor
  NFS: Don't try to reclaim delegation open state if recovery failed
  NFSv4: Ensure that we call FREE_STATEID when NFSv4.x stateids are revoked
  NFSv4: Fix races between nfs_remove_bad_delegation() and delegation return
  NFSv4.1: nfs41_clear_delegation_stateid shouldn't trust NFS_DELEGATED_STATE
  NFSv4: Ensure that we remove NFSv4.0 delegations when state has expired
  NFS: SEEK is an NFS v4.2 feature
  nfs: Fix use of uninitialized variable in nfs_getattr()
  nfs: Remove bogus assignment
  nfs: remove spurious WARN_ON_ONCE in write path
  pnfs/blocklayout: serialize GETDEVICEINFO calls
  nfs: fix pnfs direct write memory leak
  Revert "NFS: nfs4_do_open should add negative results to the dcache."
  Revert "NFS: remove BUG possibility in nfs4_open_and_get_state"
  NFSv4: Ensure nfs_atomic_open set the dentry verifier on ENOENT

Pull input subsystem updates from Dmitry Torokhov:
 "Mostly small fixups to PS/2 tochpad drivers (ALPS, Elantech,
  Synaptics) to better deal with specific hardware"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: elantech - update the documentation
  Input: elantech - provide a sysfs knob for crc_enabled
  Input: elantech - report the middle button of the touchpad
  Input: alps - ignore bad data on Dell Latitudes E6440 and E7440
  Input: alps - allow up to 2 invalid packets without resetting device
  Input: alps - ignore potential bare packets when device is out of sync
  Input: elantech - fix crc_enabled for Fujitsu H730
  Input: elantech - use elantech_report_trackpoint for hardware v4 too
  Input: twl4030-pwrbutton - ensure a wakeup event is recorded.
  Input: synaptics - add min/max quirk for Lenovo T440s

Pull arm64 fixes from Catalin Marinas:

 - fix EFI stub cache maintenance causing aborts during boot on certain
   platforms

 - handle byte stores in __clear_user without panicking

 - fix race condition in aarch64_insn_patch_text_sync() (instruction
   patching)

 - Couple of type fixes

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: ARCH_PFN_OFFSET should be unsigned long
  Correct the race condition in aarch64_insn_patch_text_sync()
  arm64: __clear_user: handle exceptions on strb
  arm64: Fix data type for physical address
  arm64: efi: Fix stub cache maintenance

Merge tag 'platform-drivers-x86-v3.18-3' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86

Pull x86 platform drivers fixlets from Darren Hart:
 "Just two patches to remove hp_accel events from the keyboard bus
  stream via an i8042 filter"

* tag 'platform-drivers-x86-v3.18-3' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
  platform: hp_accel: Add SERIO_I8042 as a dependency since it now includes i8042.h/serio.h
  platform: hp_accel: add a i8042 filter to remove HPQ6000 data from kb bus stream

Pull libata fixes from Tejun Heo:
 "The most notable is the revert of lock splitting optimization in ahci.
  This also made the IRQ handling threaded even when there's only one
  IRQ in use.  The conversion missed IRFQ_SHARED leading to screaming
  IRQs problem in some cases and the threaded IRQ handling showed
  performance regression in some LKP test cases.  The changes are
  reverted for now.  It'll probably be retried once threaded IRQ
  handling is removed from ahci.

  Other than that, there's one fix for ahci and several patches adding
  device IDs"

* 'for-3.18-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ahci: fix AHCI parameters not taken into account
  ata: sata_rcar: Add r8a7793 device support
  ahci: Add Device IDs for Intel Sunrise Point PCH
  ahci: disable MSI instead of NCQ on Samsung pci-e SSDs on macbooks
  Revert "AHCI: Optimize single IRQ interrupt processing"
  Revert "AHCI: Do not acquire ata_host::lock from single IRQ handler"
  ata: sata_rcar: Disable DIPM mode for r8a7790 ES1

Pull block layer fixes from Jens Axboe:
 "Four small fixes that should be merged for the current 3.18-rc series.
  This pull request contains:

   - a minor bugfix for computation of best IO priority given two
     merging requests.  From Jan Kara.

   - the final (final) merge count issue that has been plaguing
     virtio-blk.  From Ming Lei.

   - enable parallel reinit notify for blk-mq queues, to combine the
     cost of an RCU grace period across lots of devices.  From Tejun
     Heo.

   - an error handling fix for the SCSI_IOCTL_SEND_COMMAND ioctl.  From
     Tony Battersby"

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: blk-merge: fix blk_recount_segments()
  scsi: Fix more error handling in SCSI_IOCTL_SEND_COMMAND
  blk-mq: make mq_queue_reinit_notify() freeze queues in parallel
  block: Fix computation of merged request priority

Pull ACPI and power management fixes from Rafael Wysocki:
 "These are three regression fixes, two recent (generic power domains,
  suspend-to-idle) and one older (cpufreq), an ACPI blacklist entry for
  one more machine having problems with Windows 8 compatibility, a minor
  cpufreq driver fix (cpufreq-dt) and a fixup for new callback
  definitions (generic power domains).

  Specifics:

   - Fix a crash in the suspend-to-idle code path introduced by a recent
     commit that forgot to check a pointer against NULL before
     dereferencing it (Dmitry Eremin-Solenikov).

   - Fix a boot crash on Exynos5 introduced by a recent commit making
     that platform use generic Device Tree bindings for power domains
     which exposed a weakness in the generic power domains framework
     leading to that crash (Ulf Hansson).

   - Fix a crash during system resume on systems where cpufreq depends
     on Operation Performance Points (OPP) for functionality, but
     CONFIG_OPP is not set.  This leads the cpufreq driver registration
     to fail, but the resume code attempts to restore the pre-suspend
     cpufreq configuration (which does not exist) nevertheless and
     crashes.  From Geert Uytterhoeven.

   - Add a new ACPI blacklist entry for Dell Vostro 3546 that has
     problems if it is reported as Windows 8 compatible to the BIOS
     (Adam Lee).

   - Fix swapped arguments in an error message in the cpufreq-dt driver
     (Abhilash Kesavan).

   - Fix up the prototypes of new callbacks in struct generic_pm_domain
     to make them more useful.  Users of those callbacks will be added
     in 3.19 and it's better for them to be based on the correct struct
     definition in mainline from the start.  From Ulf Hansson and Kevin
     Hilman"

* tag 'pm+acpi-3.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / Domains: Fix initial default state of the need_restore flag
  PM / sleep: Fix entering suspend-to-IDLE if no freeze_oops is set
  PM / Domains: Change prototype for the attach and detach callbacks
  cpufreq: Avoid crash in resume on SMP without OPP
  cpufreq: cpufreq-dt: Fix arguments in clock failure error message
  ACPI / blacklist: blacklist Win8 OSI for Dell Vostro 3546

Pull firewire fix from Stefan Richter:
 "IEEE 1394 (FireWire) subsystem fix: The character device file
  interface for raw 1394 I/O took uninitialized kernel stack as
  substitute for missing ioctl() argument data.  This could partially
  show up in subsequent read() output"

* tag 'firewire-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
  firewire: cdev: prevent kernel stack leaking into ioctl arguments

Pull vfs fix from Al Viro:
 "Fix for a really embarrassing braino in iov_iter.  Kudos to paulus..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Fix thinko in iov_iter_single_seg_count

* pm-domains:
  PM / Domains: Fix initial default state of the need_restore flag
  PM / Domains: Change prototype for the attach and detach callbacks

* pm-sleep:
  PM / sleep: Fix entering suspend-to-IDLE if no freeze_oops is set

* pm-cpufreq:
  cpufreq: Avoid crash in resume on SMP without OPP
  cpufreq: cpufreq-dt: Fix arguments in clock failure error message

* acpi-blacklist:
  ACPI / blacklist: blacklist Win8 OSI for Dell Vostro 3546

Found by the UC-KLEE tool:  A user could supply less input to
firewire-cdev ioctls than write- or write/read-type ioctl handlers
expect.  The handlers used data from uninitialized kernel stack then.

This could partially leak back to the user if the kernel subsequently
generated fw_cdev_event_'s (to be read from the firewire-cdev fd)
which notably would contain the _u64 closure field which many of the
ioctl argument structures contain.

The fact that the handlers would act on random garbage input is a
lesser issue since all handlers must check their input anyway.

The fix simply always null-initializes the entire ioctl argument buffer
regardless of the actual length of expected user input.  That is, a
runtime overhead of memset(..., 40) is added to each firewirew-cdev
ioctl() call.  [Comment from Clemens Ladisch:  This part of the stack is
most likely to be already in the cache.]

Remarks:
  - There was never any leak from kernel stack to the ioctl output
    buffer itself.  IOW, it was not possible to read kernel stack by a
    read-type or write/read-type ioctl alone; the leak could at most
    happen in combination with read()ing subsequent event data.
  - The actual expected minimum user input of each ioctl from
    include/uapi/linux/firewire-cdev.h is, in bytes:
    [0x00] = 32, [0x05] =  4, [0x0a] = 16, [0x0f] = 20, [0x14] = 16,
    [0x01] = 36, [0x06] = 20, [0x0b] =  4, [0x10] = 20, [0x15] = 20,
    [0x02] = 20, [0x07] =  4, [0x0c] =  0, [0x11] =  0, [0x16] =  8,
    [0x03] =  4, [0x08] = 24, [0x0d] = 20, [0x12] = 36, [0x17] = 12,
    [0x04] = 20, [0x09] = 24, [0x0e] =  4, [0x13] = 40, [0x18] =  4.
Reported-by: David Ramos <daramos@stanford.edu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

Pull virtio bugfix from Michael S Tsirkin:
 "This fixes a crash in virtio console multi-channel mode that got
  introduced in -rc1"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_console: move early VQ enablement