On pseries machines the detection for max_bus_speed should be done
through an OpenFirmware property. This patch adds a function to perform
this detection and a hook to perform dynamic adding of the function only
for pseries. This is done by overwriting the weak
pcibios_root_bridge_prepare function which is called by
pci_create_root_bus().

From: Lucas Kannebley Tavares <lucaskt@linux.vnet.ibm.com>
Signed-off-by: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The following patch implements a new PAPR change which allows
the OS to force the use of 32 bit MSIs, regardless of what
the PCI capabilities indicate. This is required for some
devices that advertise support for 64 bit MSIs but don't
actually support them.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Make sure that current->thread.reg exists before we deference it in
flush_hash_page.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reported-by: John J Miller <millerjo@us.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Currently, the OPAL exception vectors are registered before the feature
fixups are processed. This means that the now-firmware-owned vectors
will likely be overwritten by the kernel.

This change moves the exception registration code to an early initcall,
rather than at machine_init time.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

POWER8 allows read and write of the DSCR in userspace. We added
kernel emulation so applications could always use the instructions
regardless of the CPU type.

Unfortunately there are two SPRs for the DSCR and we only added
emulation for the privileged one. Add code to match the non
privileged one.

A simple test was created to verify the fix:

http://ozlabs.org/~anton/junkcode/user_dscr_test.c

Without the patch we get a SIGILL and it passes with the patch.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Pull kvm updates from Gleb Natapov:
 "Highlights of the updates are:

  general:
   - new emulated device API
   - legacy device assignment is now optional
   - irqfd interface is more generic and can be shared between arches

  x86:
   - VMCS shadow support and other nested VMX improvements
   - APIC virtualization and Posted Interrupt hardware support
   - Optimize mmio spte zapping

  ppc:
    - BookE: in-kernel MPIC emulation with irqfd support
    - Book3S: in-kernel XICS emulation (incomplete)
    - Book3S: HV: migration fixes
    - BookE: more debug support preparation
    - BookE: e6500 support

  ARM:
   - reworking of Hyp idmaps

  s390:
   - ioeventfd for virtio-ccw

  And many other bug fixes, cleanups and improvements"

* tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
  kvm: Add compat_ioctl for device control API
  KVM: x86: Account for failing enable_irq_window for NMI window request
  KVM: PPC: Book3S: Add API for in-kernel XICS emulation
  kvm/ppc/mpic: fix missing unlock in set_base_addr()
  kvm/ppc: Hold srcu lock when calling kvm_io_bus_read/write
  kvm/ppc/mpic: remove users
  kvm/ppc/mpic: fix mmio region lists when multiple guests used
  kvm/ppc/mpic: remove default routes from documentation
  kvm: KVM_CAP_IOMMU only available with device assignment
  ARM: KVM: iterate over all CPUs for CPU compatibility check
  KVM: ARM: Fix spelling in error message
  ARM: KVM: define KVM_ARM_MAX_VCPUS unconditionally
  KVM: ARM: Fix API documentation for ONE_REG encoding
  ARM: KVM: promote vfp_host pointer to generic host cpu context
  ARM: KVM: add architecture specific hook for capabilities
  ARM: KVM: perform HYP initilization for hotplugged CPUs
  ARM: KVM: switch to a dual-step HYP init code
  ARM: KVM: rework HYP page table freeing
  ARM: KVM: enforce maximum size for identity mapped code
  ARM: KVM: move to a KVM provided HYP idmap
  ...

Give the OID registry file module information so that it doesn't taint the
kernel when compiled as a module and loaded.
Reported-by: Dros Adamson <Weston.Adamson@netapp.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Trond Myklebust <Trond.Myklebust@netapp.com>
cc: stable@vger.kernel.org
cc: linux-nfs@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull 'full dynticks' support from Ingo Molnar:
 "This tree from Frederic Weisbecker adds a new, (exciting! :-) core
  kernel feature to the timer and scheduler subsystems: 'full dynticks',
  or CONFIG_NO_HZ_FULL=y.

  This feature extends the nohz variable-size timer tick feature from
  idle to busy CPUs (running at most one task) as well, potentially
  reducing the number of timer interrupts significantly.

  This feature got motivated by real-time folks and the -rt tree, but
  the general utility and motivation of full-dynticks runs wider than
  that:

   - HPC workloads get faster: CPUs running a single task should be able
     to utilize a maximum amount of CPU power.  A periodic timer tick at
     HZ=1000 can cause a constant overhead of up to 1.0%.  This feature
     removes that overhead - and speeds up the system by 0.5%-1.0% on
     typical distro configs even on modern systems.

   - Real-time workload latency reduction: CPUs running critical tasks
     should experience as little jitter as possible.  The last remaining
     source of kernel-related jitter was the periodic timer tick.

   - A single task executing on a CPU is a pretty common situation,
     especially with an increasing number of cores/CPUs, so this feature
     helps desktop and mobile workloads as well.

  The cost of the feature is mainly related to increased timer
  reprogramming overhead when a CPU switches its tick period, and thus
  slightly longer to-idle and from-idle latency.

  Configuration-wise a third mode of operation is added to the existing
  two NOHZ kconfig modes:

   - CONFIG_HZ_PERIODIC: [formerly !CONFIG_NO_HZ], now explicitly named
     as a config option.  This is the traditional Linux periodic tick
     design: there's a HZ tick going on all the time, regardless of
     whether a CPU is idle or not.

   - CONFIG_NO_HZ_IDLE: [formerly CONFIG_NO_HZ=y], this turns off the
     periodic tick when a CPU enters idle mode.

   - CONFIG_NO_HZ_FULL: this new mode, in addition to turning off the
     tick when a CPU is idle, also slows the tick down to 1 Hz (one
     timer interrupt per second) when only a single task is running on a
     CPU.

  The .config behavior is compatible: existing !CONFIG_NO_HZ and
  CONFIG_NO_HZ=y settings get translated to the new values, without the
  user having to configure anything.  CONFIG_NO_HZ_FULL is turned off by
  default.

  This feature is based on a lot of infrastructure work that has been
  steadily going upstream in the last 2-3 cycles: related RCU support
  and non-periodic cputime support in particular is upstream already.

  This tree adds the final pieces and activates the feature.  The pull
  request is marked RFC because:

   - it's marked 64-bit only at the moment - the 32-bit support patch is
     small but did not get ready in time.

   - it has a number of fresh commits that came in after the merge
     window.  The overwhelming majority of commits are from before the
     merge window, but still some aspects of the tree are fresh and so I
     marked it RFC.

   - it's a pretty wide-reaching feature with lots of effects - and
     while the components have been in testing for some time, the full
     combination is still not very widely used.  That it's default-off
     should reduce its regression abilities and obviously there are no
     known regressions with CONFIG_NO_HZ_FULL=y enabled either.

   - the feature is not completely idempotent: there is no 100%
     equivalent replacement for a periodic scheduler/timer tick.  In
     particular there's ongoing work to map out and reduce its effects
     on scheduler load-balancing and statistics.  This should not impact
     correctness though, there are no known regressions related to this
     feature at this point.

   - it's a pretty ambitious feature that with time will likely be
     enabled by most Linux distros, and we'd like you to make input on
     its design/implementation, if you dislike some aspect we missed.
     Without flaming us to crisp! :-)

  Future plans:

   - there's ongoing work to reduce 1Hz to 0Hz, to essentially shut off
     the periodic tick altogether when there's a single busy task on a
     CPU.  We'd first like 1 Hz to be exposed more widely before we go
     for the 0 Hz target though.

   - once we reach 0 Hz we can remove the periodic tick assumption from
     nr_running>=2 as well, by essentially interrupting busy tasks only
     as frequently as the sched_latency constraints require us to do -
     once every 4-40 msecs, depending on nr_running.

  I am personally leaning towards biting the bullet and doing this in
  v3.10, like the -rt tree this effort has been going on for too long -
  but the final word is up to you as usual.

  More technical details can be found in Documentation/timers/NO_HZ.txt"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  sched: Keep at least 1 tick per second for active dynticks tasks
  rcu: Fix full dynticks' dependency on wide RCU nocb mode
  nohz: Protect smp_processor_id() in tick_nohz_task_switch()
  nohz_full: Add documentation.
  cputime_nsecs: use math64.h for nsec resolution conversion helpers
  nohz: Select VIRT_CPU_ACCOUNTING_GEN from full dynticks config
  nohz: Reduce overhead under high-freq idling patterns
  nohz: Remove full dynticks' superfluous dependency on RCU tree
  nohz: Fix unavailable tick_stop tracepoint in dynticks idle
  nohz: Add basic tracing
  nohz: Select wide RCU nocb for full dynticks
  nohz: Disable the tick when irq resume in full dynticks CPU
  nohz: Re-evaluate the tick for the new task after a context switch
  nohz: Prepare to stop the tick on irq exit
  nohz: Implement full dynticks kick
  nohz: Re-evaluate the tick from the scheduler IPI
  sched: New helper to prevent from stopping the tick in full dynticks
  sched: Kick full dynticks CPU that have more than one task enqueued.
  perf: New helper to prevent full dynticks CPUs from stopping tick
  perf: Kick full dynticks CPU if events rotation is needed
  ...

Pull perf fixes from Ingo Molnar:
 "Misc fixes plus a small hw-enablement patch for Intel IB model 58
  uncore events"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/lbr: Demand proper privileges for PERF_SAMPLE_BRANCH_KERNEL
  perf/x86/intel/lbr: Fix LBR filter
  perf/x86: Blacklist all MEM_*_RETIRED events for Ivy Bridge
  perf: Fix vmalloc ring buffer pages handling
  perf/x86/intel: Fix unintended variable name reuse
  perf/x86/intel: Add support for IvyBridge model 58 Uncore
  perf/x86/intel: Fix typo in perf_event_intel_uncore.c
  x86: Eliminate irq_mis_count counted in arch_irq_stat

Pull mudule updates from Rusty Russell:
 "We get rid of the general module prefix confusion with a binary config
  option, fix a remove/insert race which Never Happens, and (my
  favorite) handle the case when we have too many modules for a single
  commandline.  Seriously, the kernel is full, please go away!"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  modpost: fix unwanted VMLINUX_SYMBOL_STR expansion
  X.509: Support parse long form of length octets in Authority Key Identifier
  module: don't unlink the module until we've removed all exposure.
  kernel: kallsyms: memory override issue, need check destination buffer length
  MODSIGN: do not send garbage to stderr when enabling modules signature
  modpost: handle huge numbers of modules.
  modpost: add -T option to read module names from file/stdin.
  modpost: minor cleanup.
  genksyms: pass symbol-prefix instead of arch
  module: fix symbol versioning with symbol prefixes
  CONFIG_SYMBOL_PREFIX: cleanup.

Pull single_open() leak fixes from Al Viro:
 "A bunch of fixes for a moderately common class of bugs: file with
  single_open() done by its ->open() and seq_release as its ->release().

  That leaks; fortunately, it's not _too_ common (either people manage
  to RTFM that says "When using single_open(), the programmer should use
  single_release() instead of seq_release() in the file_operations
  structure to avoid a memory leak", or they just copy a correct
  instance), but grepping through the tree has caught quite a pile.

  All of that is, AFAICS, -stable fodder, for as far as the patches
  apply.  I tried to carve it up into reasonably-sized pieces (more or
  less "comes from the same tree")"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  rcutrace: single_open() leaks
  gadget: single_open() leaks
  staging: single_open() leaks
  megaraid: single_open() leak
  wireless: single_open() leaks
  input: single_open() leak
  rtc: single_open() leaks
  ds1620: single_open() leak
  sh: single_open() leaks
  parisc: single_open() leaks
  mips: single_open() leaks
  ia64: single_open() leaks
  h8300: single_open() leaks
  cris: single_open() leaks
  arm: single_open() leaks

Merge ipc fixes and cleanups from my IPC branch.

The ipc locking has always been pretty ugly, and the scalability fixes
to some degree made it even less readable.  We had two cases of double
unlocks in error paths due to this (one rcu read unlock, one semaphore
unlock), and this fixes the bugs I found while trying to clean things up
a bit so that we are less likely to have more.

* ipc-cleanups:
  ipc: simplify rcu_read_lock() in semctl_nolock()
  ipc: simplify semtimedop/semctl_main() common error path handling
  ipc: move sem_obtain_lock() rcu locking into the only caller
  ipc: fix double sem unlock in semctl error path
  ipc: move the rcu_read_lock() from sem_lock_and_putref() into callers
  ipc: sem_putref() does not need the semaphore lock any more
  ipc: move rcu_read_unlock() out of sem_unlock() and into callers

This API shouldn't have 32/64-bit issues, but VFS assumes it does
unless told otherwise.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>

We should always have proper privileges when requesting kernel
data.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/20130503121256.230745028@chello.nl
[ Fix build error reported by fengguang.wu@intel.com, propagate error code back. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/n/tip-v0x9ky3ahzr6nm3c6ilwrili@git.kernel.org

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Pull networking fixes from David Miller:

 1) Several routines do not use netdev_features_t to hold such bitmasks,
    fixes from Patrick McHardy and Bjørn Mork.

 2) Update cpsw IRQ software state and the actual HW irq enabling in the
    correct order.  From Mugunthan V N.

 3) When sending tipc packets to multiple bearers, we have to make
    copies of the SKB rather than just giving the original SKB directly.
    Fix from Gerlando Falauto.

 4) Fix race with bridging topology change timer, from Stephen
    Hemminger.

 5) Fix TCPv6 segmentation handling in GRE and VXLAN, from Pravin B
    Shelar.

 6) Endian bug in USB pegasus driver, from Dan Carpenter.

 7) Fix crashes on MTU reduction in USB asix driver, from Holger
    Eitzenberger.

 8) Don't allow the kernel to BUG() just because the user puts some crap
    in an AF_PACKET mmap() ring descriptor.  Fix from Daniel Borkmann.

 9) Don't use variable sized arrays on the stack in xen-netback, from
    Wei Liu.

10) Fix stats reporting and an unbalanced napi_disable() in be2net
    driver.  From Somnath Kotur and Ajit Khaparde.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (25 commits)
  cxgb4: fix error recovery when t4_fw_hello returns a positive value
  sky2: Fix crash on receiving VLAN frames
  packet: tpacket_v3: do not trigger bug() on wrong header status
  asix: fix BUG in receive path when lowering MTU
  net: qmi_wwan: Add Telewell TW-LTE 4G
  usbnet: pegasus: endian bug in write_mii_word()
  vxlan: Fix TCPv6 segmentation.
  gre: Fix GREv4 TCPv6 segmentation.
  bridge: fix race with topology change timer
  tipc: pskb_copy() buffers when sending on more than one bearer
  tipc: tipc_bcbearer_send(): simplify bearer selection
  tipc: cosmetic: clean up comments and break a long line
  drivers: net: cpsw: irq not disabled in cpsw isr in particular sequence
  xen-netback: better names for thresholds
  xen-netback: avoid allocating variable size array on stack
  xen-netback: remove redundent parameter in netbk_count_requests
  be2net: Fix to fail probe if MSI-X enable fails for a VF
  be2net: avoid napi_disable() when it has not been enabled
  be2net: Fix firmware download for Lancer
  be2net: Fix to receive Multicast Packets when Promiscuous mode is enabled on certain devices
  ...

Pull sparc updates from David Miller:

 1) Hibernation support, as well as removal of excess interrupt
    twiddling in MMU context allocation on sparc64 from Kirill Tkhai.

 2) Kill references to __ARCH_WANT_UNLOCKED_CTXSW.

 3) Sparc32 LEON bug fixes from Daniel Hellstrom and Andreas Larsson.

 4) Provide cmpxchg64(), from Geert Uytterhoeven.

 5) Device refcount and registry bug fixes from Federico Vaga and Wei
    Yongjun.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next:
  serial: sunsu: add missing platform_driver_unregister() when module exit
  sparc32, leon: Do not overwrite previously set irq flow handlers
  sparc/kernel/vio.c: add put_device() after device_find_child()
  sparc64: Do not save/restore interrupts in get_new_mmu_context()
  sparc: Consistently use 'wr' and 'rd' instructions for ASRs.
  sparc64: Kill __ARCH_WANT_UNLOCKED_CTXSW
  sparc64: Provide cmpxchg64()
  sparc64: Do not change num_physpages during initmem freeing
  sparc64: Hibernation support
  sparc,leon: updated GRPCI2 config name
  sparc,leon: support for GRPCI1 PCI host bridge controller
  sparc32,leon: add support for PCI busn resource for GRPCI2

Merge sparc bug fixes that didn't make it into v3.9 into
sparc-next.
Signed-off-by: David S. Miller <davem@davemloft.net>

We have registered platform driver when module init, and
need unregister it when module exit.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>

This is needed because when scan_of_devices finds the GAISLER_GPTIMER
core that corresponds to the SMP "ticker" timer, the previously set
proper irq flow handler gets overwritten with an incorrect one. This
leads to very flaky timer interrupt handling on some hardware. Proper
updates to handlers can still be done using leon_update_virq_handling.
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The vio_remove() function uses device_find_child() but it does not drop
the reference of the retrieved child.
Signed-off-by: Federico Vaga <federico.vaga@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This trivially combines two rcu_read_lock() calls in both sides of a
if-statement into one single one in front of the if-statement.

Split out as an independent cleanup from the previous commit.
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With various straight RCU lock/unlock movements, one common exit path
pattern had become

	rcu_read_unlock();
	goto out_wakeup;

and in fact there were no cases where we wanted to exit to out_wakeup
_without_ releasing the RCU read lock.

So replace that pattern with "goto out_rcu_wakeup", and remove the old
out_wakeup.
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sem_obtain_lock() was another of those functions that returned with the
RCU lock held for reading in the success case.  Move the RCU locking to
the caller (semtimedop()), making it more obvious.  We already did RCU
locking elsewhere in that function.

Side note: why does semtimedop() re-do the semphore lookup after the
sleep, rather than just getting a reference to the semaphore it already
looked up originally?
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix another ipc locking buglet introduced by the scalability patches:
when semctl_down() was changed to delay the semaphore locking, one error
path for security_sem_semctl() went through the semaphore unlock logic
even though the semaphore had never been locked.

Introduced by commit 16df3674 ("ipc,sem: do not hold ipc lock more
than necessary")
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is another ipc semaphore locking cleanup, trying to make the
locking more straightforward.  We move the rcu read locking into the
callers of sem_lock_and_putref(), which in general means that we now
mostly do the rcu_read_lock() and rcu_read_unlock() in the same
function.

Mostly.  We still have the ipc_addid/newary/freeary mess, and things
like ipcctl_pre_down_nolock().
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>