Pull ARM SoC fixes from Arnd Bergmann:
 -  multiple omap2+ bug fixes
 - a regression on ux500 dt support
 - a build failure on shmobile

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: OMAP2+: omap2plus_defconfig: EHCI driver is not stable, disable it
  ARM: shmobile: fix platsmp.c build when ARCH_SH73A0=n
  ARM: ux500: Over-ride the DT device naming scheme for pinctrl
  ARM: ux500: Fix build errors/warnings when MACH_UX500_DT is not set
  of: address: Don't fail a lookup just because a node has no reg property
  ARM: OMAP2+: hwmod code/clockdomain data: fix 32K sync timer

Pull power management fix from Rafael Wysocki:
 "This removes ACPICA code that had already been removed once from the
  kernel already by commit 2780cc46 ("[ACPI] Fix suspend/resume
  lockup issue by leaving Bus Master Arbitration enabled"), because it
  was known to cause systems to lock up during resume from suspend, but
  was re-introduced by mistake during the v3.4 merge window."

* tag 'pm-for-3.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / PM: Leave Bus Master Arbitration enabled for suspend/resume

Pull printk fixes from Greg Kroah-Hartman:
 "Here are some more printk fixes for 3.5-rc6.  They resolve all known
  outstanding issues with the printk changes that have been happening.
  They have been tested by the people reporting the problems.

  This hopefully should be it for the printk stuff for 3.5-final.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'driver-core-3.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kmsg: merge continuation records while printing
  kmsg: /proc/kmsg - support reading of partial log records
  kmsg: make sure all messages reach a newly registered boot console
  kmsg: properly handle concurrent non-blocking read() from /proc/kmsg
  kmsg: add the facility number to the syslog prefix
  kmsg: escape the backslash character while exporting data
  printk: replacing the raw_spin_lock/unlock with raw_spin_lock/unlock_irq

Pull USB fixes from Greg Kroah-Hartman:
 "Here are a few fixes and new device ids for the 3.5-rc6 tree.

  The PCI changes resolve a long-standing issue with resuming some EHCI
  controllers.  It has been acked by the PCI maintainer, and he asked
  for it to go through my USB tree instead of his.

  The xhci patches also resolve a number of reported issues.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'usb-3.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  PCI: EHCI: fix crash during suspend on ASUS computers
  USB: cdc-wdm: fix lockup on error in wdm_read
  USB: metro-usb: fix tty_flip_buffer_push use
  USB: option: Add MEDIATEK product ids
  USB: option: add ZTE MF60
  xhci: Fix hang on back-to-back Set TR Deq Ptr commands.
  usb: Add support for root hub port status CAS

Pull misc fix from Greg Kroah-Hartman:
 "Here's a single MEI driver fix that resolves a regression from 3.4
  that a number of people have reported (and sent to me in different
  patches.)

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'char-misc-3.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  mei: pci_resume: set IRQF_ONESHOT for msi request_threaded_irq

Pull a late GPIO fix from Linus Walleij:
 "Grr! So typically -next washed out a bug in the bug fixes.  This v2 of
  the pull request fixes another OF/DT related issue caused by fixing
  another OF/DT related issue, courtesy of Gerard Sintselaar.

  So please pull the v2.  Or pull it on top of the other one, whatever.
  Sorry for the panic mode, I'm in the middle of the Swedish woods,
  supposedly on vacation."

* tag 'fixes-for-v3.5-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio/gpio-tps65910: gpio_chip.of_node referenced without CONFIG_OF_GPIO defined

The declaration of arch_release_thread_info() needs a semicolon.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

commit 626f9914 added code to initialize gpio_chip.of_node, but if
CONFIG_OF_GPIO is not defined gps-tps65910 fails to build with an
error complaining gpio_chip has no member of_node. I ran into this
while doing a allyesconfig build on linux-next.
Signed-off-by: Gerard Snitselaar <dev@snitselaar.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Pull GPIO fixes from Linus Walleij:
 "Yes, this is a *LATE* GPIO pull request with fixes for v3.5.

  Grant moved across the planet and accidentally fell off the grid, so
  he asked me to take over the GPIO merges for a while 10 days ago.

  Since then I went over the archives and collected this pile of fixes,
  and pulled two of them from the TI maintainer Kevin Hilman.  Then
  waited for them to at least hit linux-next once or twice."

GPIO fixes for v3.5:
 - Invalid context restore on bank 0 for OMAP driver in runtime
   suspend/resume cycle
 - Check for NULL platform data in sta-2x11 driver
 - Constrain selection of the V1 MSM GPIO driver to applicable platforms
   (Kconfig issue)
 - Make sure the correct output value is set in the wm8994 driver
 - Export devm_gpio_request_one() so it can be used in modules.
   Apparently some in-kernel modules can be configured to use this
   leading to breakage.
 - Check that the GPIO is valid in the lantiq driver
 - Fix the flag bits introduced for v3.5, so they don't overlap
 - Fix a device tree intialization bug for imx21-compatible devices
 - Carry over the OF node to the TPS65910 GPIO chip struct

* tag 'fixes-for-v3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: tps65910: initialize of_node of gpio_chip
  gpio/mxc: make irqs work for fsl,imx21-gpio devices
  gpio: fix bits conflict for gpio flags
  mips: pci-lantiq: Fix check for valid gpio
  gpio: export devm_gpio_request_one
  gpiolib: wm8994: Pay attention to the value set when enabling as output
  gpio/msm_v1: CONFIG_GPIO_MSM_V1 is only available on three SoCs
  gpio-sta2x11: don't use pdata if null
  gpio/omap: fix invalid context restore of gpio bank-0
  gpio/omap: fix irq loss while in idle with debounce on

Pull powerpc fixes from Benjamin Herrenschmidt:
 "It looks like my rewrite of our lazy irq scheme is still exposing
  "interesting" issues left and right.  The previous fixes are now
  causing an occasional BUG_ON to trigger (which this patch turns into a
  WARN_ON while at it), due to another issue of disconnect of the lazy
  irq state vs the processor state in the idle loop on pseries and
  cell.

  This should fix it properly once for all moving the nasty code to a
  common helper function.

  There's also couple more fixes for some debug stuff that didn't build
  (and helped resolving those problems so it's worth having), along with
  a compile fix for newer gcc's."

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  tty/hvc_opal: Fix debug function name
  powerpc/numa: Avoid stupid uninitialized warning from gcc
  powerpc: Fix build of some debug irq code
  powerpc: More fixes for lazy IRQ vs. idle

This is an old suspend/resume lockup fix:

	commit 2780cc46
	Author: Len Brown <len.brown@intel.com>
	Date:   Thu Dec 23 13:43:30 2004 -0500

	    [ACPI] Fix suspend/resume lockup issue
	    by leaving Bus Master Arbitration enabled.
	    The ACPI spec mandates it be disabled only for C3.

	    http://bugzilla.kernel.org/show_bug.cgi?id=3599Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

The bug snuck back in in commit 2feec47d (ACPICA: ACPI 5: Support
for new FADT SleepStatus, SleepControl registers, 2012-02-14),
presumably by copy/pasting a copy of the code without that fix for the
legacy case.

On affected machines, after that commit, the machine locks up hard on
resume from suspend.  The same fix as seven years ago still works.

Addresses <https://bugzilla.kernel.org/show_bug.cgi?id=43641>.
Reported-bisected-and-tested-by: Octavio Alvarez <alvarezp@alvarezp.com>
Reported-by: Adrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

This reverts commit 107a84e6.

Meelis Roos reports a regression since 3.5-rc5 that stops Sun Fire V100
and Sun Netra X1 sparc64 machines from booting, hanging after enabling
serial console.  He bisected it to commit 107a84e6.

Rob Herring explains:
 "The problem is match combinations of compatible plus name and/or type
  fail to match correctly.  I have a fix for this, but given how late it
  is for 3.5 I think it is best to revert this for now.  There could be
  other cases that rely on the current although wrong behavior.  I will
  post an updated version for 3.6."
Bisected-and-reported-by: Meelis Roos <mroos@linux.ee>
Requested-by: Rob Herring <rob.herring@calxeda.com>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

when the default irq quick handler is used then IRQF_ONESHOT must be set
otherwise the request fails and following error is displayed:

mei 0000:00:16.0: irq 48 for MSI/MSI-X
genirq: Threaded irq requested with handler=NULL and !ONESHOT for irq 48
mei 0000:00:16.0: request_threaded_irq failed: irq = 48.
dpm_run_callback(): pci_pm_resume+0x0/0x140 returns -22
PM: Device 0000:00:16.0 failed to resume async: error -22
Reported-by: Peter Wu <lekensteyn@gmail.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Tested-by: Peter Wu <lekensteyn@gmail.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: stable <stable@vger.kernel.org> # 3.5
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Quite a few ASUS computers experience a nasty problem, related to the
EHCI controllers, when going into system suspend.  It was observed
that the problem didn't occur if the controllers were not put into the
D3 power state before starting the suspend, and commit
151b6128 (USB: EHCI: fix crash during
suspend on ASUS computers) was created to do this.

It turned out this approach messed up other computers that didn't have
the problem -- it prevented USB wakeup from working.  Consequently
commit c2fb8a3f (USB: add
NO_D3_DURING_SLEEP flag and revert 151b6128) was merged; it
reverted the earlier commit and added a whitelist of known good board
names.

Now we know the actual cause of the problem.  Thanks to AceLan Kao for
tracking it down.

According to him, an engineer at ASUS explained that some of their
BIOSes contain a bug that was added in an attempt to work around a
problem in early versions of Windows.  When the computer goes into S3
suspend, the BIOS tries to verify that the EHCI controllers were first
quiesced by the OS.  Nothing's wrong with this, but the BIOS does it
by checking that the PCI COMMAND registers contain 0 without checking
the controllers' power state.  If the register isn't 0, the BIOS
assumes the controller needs to be quiesced and tries to do so.  This
involves making various MMIO accesses to the controller, which don't
work very well if the controller is already in D3.  The end result is
a system hang or memory corruption.

Since the value in the PCI COMMAND register doesn't matter once the
controller has been suspended, and since the value will be restored
anyway when the controller is resumed, we can work around the BIOS bug
simply by setting the register to 0 during system suspend.  This patch
(as1590) does so and also reverts the second commit mentioned above,
which is now unnecessary.

In theory we could do this for every PCI device.  However to avoid
introducing new problems, the patch restricts itself to EHCI host
controllers.

Finally the affected systems can suspend with USB wakeup working
properly.

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=37632
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=42728Based-on-patch-by: AceLan Kao <acelan.kao@canonical.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Dâniel Fraga <fragabr@gmail.com>
Tested-by: Javier Marcet <jmarcet@gmail.com>
Tested-by: Andrey Rahmatullin <wrar@wrar.name>
Tested-by: Oleksij Rempel <bug-track@fisher-privat.net>
Tested-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Cc: stable <stable@vger.kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge tag 'omap-fixes-for-v3.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

From Tony Lindgren <tony@atomide.com>:
Here is one PM regression fix and a defconfig change to disable
echi-omap because the driver currently causes issues with PM.
This annoys Kevin as it makes it harder for him to validate that
PM is working. The proper fixes for the echi-omap are being
discussed, but looks like it will not be properly working with PM
until in v3.7.

* tag 'omap-fixes-for-v3.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: OMAP2+: omap2plus_defconfig: EHCI driver is not stable, disable it
  ARM: OMAP2+: hwmod code/clockdomain data: fix 32K sync timer
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

udbg_init_debug_opal() should be udbg_init_debug_opal_raw() as
the caller in arch/powerpc/kernel/udbg.c expects
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Newer gcc are being a bit blind here (it's pretty obvious we don't
reach the code path using the array if we haven't initialized the
pointer) but none of that is performance critical so let's just
silence it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

There was a typo, checking for CONFIG_TRACE_IRQFLAG instead of
CONFIG_TRACE_IRQFLAGS causing some useful debug code to not be
built

This in turns causes a build error on BookE 64-bit due to incorrect
semicolons at the end of a couple of macros, so let's fix that too
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@vger.kernel.org [v3.4]

Looks like we still have issues with pSeries and Cell idle code
vs. the lazy irq state. In fact, the reset fixes that went upstream
are exposing the problem more by causing BUG_ON() to trigger (which
this patch turns into a WARN_ON instead).

We need to be careful when using a variant of low power state that
has the side effect of turning interrupts back on, to properly set
all the SW & lazy state to look as if everything is enabled before
we enter the low power state with MSR:EE off as we will return with
MSR:EE on. If not, we have a discrepancy of state which can cause
things to go very wrong later on.

This patch moves the logic into a helper and uses it from the
pseries and cell idle code. The power4/970 idle code already got
things right (in assembly even !) so I'm not touching it. The power7
"bare metal" idle code is subtly different and correct. Remains PA6T
and some hypervisor based Cell platforms which have questionable
code in there, but they are mostly dead platforms so I'll fix them
when I manage to get final answers from the respective maintainers
about how the low power state actually works on them.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@vger.kernel.org [v3.4]

Pull regulator fix from Mark Brown:
 "A smallish fix for a lock dependency issue which affects a bunch of
  Qualcomm boards that do unusually complicated things with their
  regulators, the API is unlikely to be called by any other system."

* tag 'regulator-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: Fix recursive mutex lockdep warning

Don't call v4l2_ctrl_g_ctrl on ctrls which the model cam in question
does not have.
Reported-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
[ Taken directly, since Mauro is on vacation ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'virtio-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus

Pull minor virtio-balloon fix from Rusty Russell:
 "Theoretical fix, which greatly simplifies upcoming balloon patches
  which will go in via some vm tree."

* tag 'virtio-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  virtio-balloon: fix add/get API use

Pull rpmsg fixes from Ohad Ben-Cohen:
 "Fixing two (somewhat rare) endpoint-related race issues, both of which
  were reported by Fernando Guzman Lugo."

* tag 'rpmsg-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/rpmsg:
  rpmsg: make sure inflight messages don't invoke just-removed callbacks
  rpmsg: avoid premature deallocation of endpoints

Pull remoteproc fixes from Ohad Ben-Cohen:
 "Two build-related remoteproc fixes for 3.5."

* tag 'remoteproc-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/remoteproc:
  remoteproc: fix missing CONFIG_FW_LOADER configurations
  remoteproc/omap: fix randconfig unmet direct dependencies

Pull hwspinlock fix from Ohad Ben-Cohen:
 "A single hwspinlock core fix for multiple hwspinlock devices
  scenarios, from Shinya Kuribayashi."

* tag 'hwspinlock-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock:
  hwspinlock/core: use global ID to register hwspinlocks on multiple devices

In (the unlikely) case our continuation merge buffer is busy, we unfortunately
can not merge further continuation printk()s into a single record and have to
store them separately, which leads to split-up output of these lines when they
are printed.

Add some flags about newlines and prefix existence to these records and try to
reconstruct the full line again, when the separated records are printed.
Reported-By: Michael Neuling <mikey@neuling.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Tested-By: Michael Neuling <mikey@neuling.org>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull IOMMU fixes from Joerg Roedel:
 "The patches fix several issues in the AMD IOMMU driver, the NVidia
  SMMU driver, and the DMA debug code.

  The most important fix for the AMD IOMMU solves a problem with SR-IOV
  devices where virtual functions did not work with IOMMU enabled.  The
  NVidia SMMU patch fixes a possible sleep while spin-lock situation
  (queued the small fix for v3.5, a better but more intrusive fix is
  coming for v3.6).  The DMA debug patches fix a possible data
  corruption issue due to bool vs u32 usage."

* tag 'iommu-fixes-v3.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/amd: fix type bug in flush code
  dma-debug: debugfs_create_bool() takes a u32 pointer
  iommu/tegra: smmu: Fix unsleepable memory allocation
  iommu/amd: Initialize dma_ops for hotplug and sriov devices
  iommu/amd: Fix missing iommu_shutdown initialization in passthrough mode

Restore support for partial reads of any size on /proc/kmsg, in case the
supplied read buffer is smaller than the record size.

Some people seem to think is is ia good idea to run:
  $ dd if=/proc/kmsg bs=1 of=...
as a klog bridge.

Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=44211Reported-by: Jukka Ollila <jiiksteri@gmail.com>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The EHCI driver is not stable enough to be enabled by default.  In v3.5,
it has at least the following problems:

- warning dump during bootup
- hang during suspend
- prevents CORE powerdomain from entering retention during idle (even
  when no USB devices connected.)

This demonstrates that this driver has not been thoroughly tested and
therfore should not be enabled in the default defconfig.

In addition, the problems above cause new PM regressions which need be
addressed before this driver should be enabled in the default
defconfig.
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

Since ee7cd898 'virtio: expose added
descriptors immediately.', in virtio balloon virtqueue_get_buf might
now run concurrently with virtqueue_kick.  I audited both and this
seems safe in practice but this is not guaranteed by the API.
Additionally, a spurious interrupt might in theory make
virtqueue_get_buf run in parallel with virtqueue_add_buf, which is
racy.

While we might try to protect against spurious callbacks it's
easier to fix the driver: balloon seems to be the only one
(mis)using the API like this, so let's just fix balloon.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (removed unused var)

Pull cgroup fixes from Tejun Heo:
 "The previous cgroup pull request contained a patch to fix a race
  condition during cgroup hierarchy umount.  Unfortunately, while the
  patch reduced the race window such that the test case I and Sasha were
  using didn't trigger it anymore, it wasn't complete - Shyju and Li
  could reliably trigger the race condition using a different test case.

  The problem wasn't the gap between dentry deletion and release which
  the previous patch tried to fix.  The window was between the last
  dput() of a root's child and the resulting dput() of the root.  For
  cgroup dentries, the deletion and release always happen synchronously.
  As this releases the s_active ref, the refcnt of the root dentry,
  which doesn't hold s_active, stays above zero without the
  corresponding s_active.  If umount was in progress, the last
  deactivate_super() proceeds to destory the superblock and triggers
  BUG() on the non-zero root dentry refcnt after shrinking.

  This issue surfaced because cgroup dentries are now allowed to linger
  after rmdir(2) since 3.5-rc1.  Before, rmdir synchronously drained the
  dentry refcnt and the s_active acquired by rmdir from vfs layer
  protected the whole thing.  After 3.5-rc1, cgroup may internally hold
  and put dentry refs after rmdir finishes and the delayed dput()
  doesn't have surrounding s_active ref exposing this issue.

  This pull request contains two patches - one reverting the previous
  incorrect fix and the other adding the surrounding s_active ref around
  the delayed dput().

  This is quite late in the release cycle but the change is on the safer
  side and fixes the test cases reliably, so I don't think it's too
  crazy."

* 'for-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix cgroup hierarchy umount race
  Revert "cgroup: superblock can't be released with active dentries"

Pull security docs update from James Morris.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  security: Minor improvements to no_new_privs documentation

We already use them for openat() and friends, but fchdir() also wants to
be able to use O_PATH file descriptors.  This should make it comparable
to the O_SEARCH of Solaris.  In particular, O_PATH allows you to access
(not-quite-open) a directory you don't have read persmission to, only
execute permission.

Noticed during development of multithread support for ksh93.
Reported-by: ольга крыжановская <olga.kryzhanovska@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org    # O_PATH introduced in 3.0+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

48ddbe19 "cgroup: make css->refcnt clearing on cgroup removal
optional" allowed a css to linger after the associated cgroup is
removed.  As a css holds a reference on the cgroup's dentry, it means
that cgroup dentries may linger for a while.

Destroying a superblock which has dentries with positive refcnts is a
critical bug and triggers BUG() in vfs code.  As each cgroup dentry
holds an s_active reference, any lingering cgroup has both its dentry
and the superblock pinned and thus preventing premature release of
superblock.

Unfortunately, after 48ddbe19, there's a small window while
releasing a cgroup which is directly under the root of the hierarchy.
When a cgroup directory is released, vfs layer first deletes the
corresponding dentry and then invokes dput() on the parent, which may
recurse further, so when a cgroup directly below root cgroup is
released, the cgroup is first destroyed - which releases the s_active
it was holding - and then the dentry for the root cgroup is dput().

This creates a window where the root dentry's refcnt isn't zero but
superblock's s_active is.  If umount happens before or during this
window, vfs will see the root dentry with non-zero refcnt and trigger
BUG().

Before 48ddbe19, this problem didn't exist because the last dentry
reference was guaranteed to be put synchronously from rmdir(2)
invocation which holds s_active around the whole process.

Fix it by holding an extra superblock->s_active reference across
dput() from css release, which is the dput() path added by 48ddbe19
and the only one which doesn't hold an extra s_active ref across the
final cgroup dput().
Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <4FEEA5CB.8070809@huawei.com>
Reported-by: shyju pv <shyju.pv@huawei.com>
Tested-by: shyju pv <shyju.pv@huawei.com>
Cc: Sasha Levin <levinsasha928@gmail.com>
Acked-by: Li Zefan <lizefan@huawei.com>

This reverts commit fa980ca8.  The
commit was an attempt to fix a race condition where a cgroup hierarchy
may be unmounted with positive dentry reference on root cgroup.  While
the commit made the race condition slightly more difficult to trigger,
the race was still there and could be reliably triggered using a
different test case.

Revert the incorrect fix.  The next commit will describe the race and
fix it correctly.
Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <4FEEA5CB.8070809@huawei.com>
Reported-by: shyju pv <shyju.pv@huawei.com>
Cc: Sasha Levin <levinsasha928@gmail.com>
Acked-by: Li Zefan <lizefan@huawei.com>

Commit 300bab97 (hwspinlock/core: register a bank of hwspinlocks in a
single API call, 2011-09-06) introduced 'hwspin_lock_register_single()'
to register numerous (a bank of) hwspinlock instances in a single API,
'hwspin_lock_register()'.

At which time, 'hwspin_lock_register()' accidentally passes 'local IDs'
to 'hwspin_lock_register_single()', despite that ..._single() requires
'global IDs' to register hwspinlocks.

We have to convert into global IDs by supplying the missing 'base_id'.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
[ohad: fix error path of hwspin_lock_register, too]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>

Pull ARM fixes from Russell King:
 "Last merge window, we had some updates from Al cleaning up the signal
  restart handling.  These have caused some problems on ARM, and while
  Al has some fixes, we have some concerns with Al's patches but we've
  been unsuccesful with discussing this.

  We have got to the point where we need to do something, and we've
  decided that the best solution is to revert the appropriate commits
  until Al is able to reply to us.

  Also included here are four patches to fix warnings that I've noticed
  in my build system, and one fix for kprobes test code."

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: fix warning caused by wrongly typed arm_dma_limit
  ARM: fix warnings about atomic64_read
  ARM: 7440/1: kprobes: only test 'sub pc, pc, #1b-2b+8-2' on ARMv6
  ARM: 7441/1: perf: return -EOPNOTSUPP if requested mode exclusion is unavailable
  ARM: 7443/1: Revert "new way of handling ERESTART_RESTARTBLOCK"
  ARM: 7442/1: Revert "remove unused restart trampoline"
  ARM: fix set_domain() macro
  ARM: fix mach-versatile/pci.c warning

The documentation didn't actually mention how to enable no_new_privs.
This also adds a note about possible interactions between
no_new_privs and LSMs (i.e. why teaching systemd to set no_new_privs
is not necessarily a good idea), and it references the new docs
from include/linux/prctl.h.
Suggested-by: Rob Landley <rob@landley.net>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>