The following program illustrates the problem:

    char buf[8192];

    int fd = open("/proc/self/maps", O_RDONLY);

    n = pread(fd, buf, sizeof(buf), 0);
    printf("%d\n", n);

    /* lseek(fd, 0, SEEK_CUR); */ /* Uncomment to work around */

    n = pread(fd, buf, sizeof(buf), 0);
    printf("%d\n", n);

The second printf() prints zero, but uncommenting the lseek() corrects its
behaviour.

To fix, make seq_read() mirror seq_lseek() when processing changes in
*ppos.  Restore m->version first, then if required traverse and update
read_pos on success.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=11856Signed-off-by: NEarl Chew <echew@ixiacom.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix a code indentation in the function intel_idle_cpu_init that looks
confusing.o
Suggested-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Reviewed-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NMarcos Paulo de Souza <marcos.mage@gmail.com>
Cc: "Brown, Len" <len.brown@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

i386 allnoconfig:

  fs/namei.c: In function 'has_zero':
  fs/namei.c:1617: warning: integer constant is too large for 'unsigned long' type
  fs/namei.c:1617: warning: integer constant is too large for 'unsigned long' type
  fs/namei.c: In function 'hash_name':
  fs/namei.c:1635: warning: integer constant is too large for 'unsigned long' type

There must be a tidier way of doing this.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In some cases it may happen that pmd_none_or_clear_bad() is called with
the mmap_sem hold in read mode.  In those cases the huge page faults can
allocate hugepmds under pmd_none_or_clear_bad() and that can trigger a
false positive from pmd_bad() that will not like to see a pmd
materializing as trans huge.

It's not khugepaged causing the problem, khugepaged holds the mmap_sem
in write mode (and all those sites must hold the mmap_sem in read mode
to prevent pagetables to go away from under them, during code review it
seems vm86 mode on 32bit kernels requires that too unless it's
restricted to 1 thread per process or UP builds).  The race is only with
the huge pagefaults that can convert a pmd_none() into a
pmd_trans_huge().

Effectively all these pmd_none_or_clear_bad() sites running with
mmap_sem in read mode are somewhat speculative with the page faults, and
the result is always undefined when they run simultaneously.  This is
probably why it wasn't common to run into this.  For example if the
madvise(MADV_DONTNEED) runs zap_page_range() shortly before the page
fault, the hugepage will not be zapped, if the page fault runs first it
will be zapped.

Altering pmd_bad() not to error out if it finds hugepmds won't be enough
to fix this, because zap_pmd_range would then proceed to call
zap_pte_range (which would be incorrect if the pmd become a
pmd_trans_huge()).

The simplest way to fix this is to read the pmd in the local stack
(regardless of what we read, no need of actual CPU barriers, only
compiler barrier needed), and be sure it is not changing under the code
that computes its value.  Even if the real pmd is changing under the
value we hold on the stack, we don't care.  If we actually end up in
zap_pte_range it means the pmd was not none already and it was not huge,
and it can't become huge from under us (khugepaged locking explained
above).

All we need is to enforce that there is no way anymore that in a code
path like below, pmd_trans_huge can be false, but pmd_none_or_clear_bad
can run into a hugepmd.  The overhead of a barrier() is just a compiler
tweak and should not be measurable (I only added it for THP builds).  I
don't exclude different compiler versions may have prevented the race
too by caching the value of *pmd on the stack (that hasn't been
verified, but it wouldn't be impossible considering
pmd_none_or_clear_bad, pmd_bad, pmd_trans_huge, pmd_none are all inlines
and there's no external function called in between pmd_trans_huge and
pmd_none_or_clear_bad).

		if (pmd_trans_huge(*pmd)) {
			if (next-addr != HPAGE_PMD_SIZE) {
				VM_BUG_ON(!rwsem_is_locked(&tlb->mm->mmap_sem));
				split_huge_page_pmd(vma->vm_mm, pmd);
			} else if (zap_huge_pmd(tlb, vma, pmd, addr))
				continue;
			/* fall through */
		}
		if (pmd_none_or_clear_bad(pmd))

Because this race condition could be exercised without special
privileges this was reported in CVE-2012-1179.

The race was identified and fully explained by Ulrich who debugged it.
I'm quoting his accurate explanation below, for reference.

====== start quote =======
      mapcount 0 page_mapcount 1
      kernel BUG at mm/huge_memory.c:1384!

    At some point prior to the panic, a "bad pmd ..." message similar to the
    following is logged on the console:

      mm/memory.c:145: bad pmd ffff8800376e1f98(80000000314000e7).

    The "bad pmd ..." message is logged by pmd_clear_bad() before it clears
    the page's PMD table entry.

        143 void pmd_clear_bad(pmd_t *pmd)
        144 {
    ->  145         pmd_ERROR(*pmd);
        146         pmd_clear(pmd);
        147 }

    After the PMD table entry has been cleared, there is an inconsistency
    between the actual number of PMD table entries that are mapping the page
    and the page's map count (_mapcount field in struct page). When the page
    is subsequently reclaimed, __split_huge_page() detects this inconsistency.

       1381         if (mapcount != page_mapcount(page))
       1382                 printk(KERN_ERR "mapcount %d page_mapcount %d\n",
       1383                        mapcount, page_mapcount(page));
    -> 1384         BUG_ON(mapcount != page_mapcount(page));

    The root cause of the problem is a race of two threads in a multithreaded
    process. Thread B incurs a page fault on a virtual address that has never
    been accessed (PMD entry is zero) while Thread A is executing an madvise()
    system call on a virtual address within the same 2 MB (huge page) range.

               virtual address space
              .---------------------.
              |                     |
              |                     |
            .-|---------------------|
            | |                     |
            | |                     |<-- B(fault)
            | |                     |
      2 MB  | |/////////////////////|-.
      huge <  |/////////////////////|  > A(range)
      page  | |/////////////////////|-'
            | |                     |
            | |                     |
            '-|---------------------|
              |                     |
              |                     |
              '---------------------'

    - Thread A is executing an madvise(..., MADV_DONTNEED) system call
      on the virtual address range "A(range)" shown in the picture.

    sys_madvise
      // Acquire the semaphore in shared mode.
      down_read(&current->mm->mmap_sem)
      ...
      madvise_vma
        switch (behavior)
        case MADV_DONTNEED:
             madvise_dontneed
               zap_page_range
                 unmap_vmas
                   unmap_page_range
                     zap_pud_range
                       zap_pmd_range
                         //
                         // Assume that this huge page has never been accessed.
                         // I.e. content of the PMD entry is zero (not mapped).
                         //
                         if (pmd_trans_huge(*pmd)) {
                             // We don't get here due to the above assumption.
                         }
                         //
                         // Assume that Thread B incurred a page fault and
             .---------> // sneaks in here as shown below.
             |           //
             |           if (pmd_none_or_clear_bad(pmd))
             |               {
             |                 if (unlikely(pmd_bad(*pmd)))
             |                     pmd_clear_bad
             |                     {
             |                       pmd_ERROR
             |                         // Log "bad pmd ..." message here.
             |                       pmd_clear
             |                         // Clear the page's PMD entry.
             |                         // Thread B incremented the map count
             |                         // in page_add_new_anon_rmap(), but
             |                         // now the page is no longer mapped
             |                         // by a PMD entry (-> inconsistency).
             |                     }
             |               }
             |
             v
    - Thread B is handling a page fault on virtual address "B(fault)" shown
      in the picture.

    ...
    do_page_fault
      __do_page_fault
        // Acquire the semaphore in shared mode.
        down_read_trylock(&mm->mmap_sem)
        ...
        handle_mm_fault
          if (pmd_none(*pmd) && transparent_hugepage_enabled(vma))
              // We get here due to the above assumption (PMD entry is zero).
              do_huge_pmd_anonymous_page
                alloc_hugepage_vma
                  // Allocate a new transparent huge page here.
                ...
                __do_huge_pmd_anonymous_page
                  ...
                  spin_lock(&mm->page_table_lock)
                  ...
                  page_add_new_anon_rmap
                    // Here we increment the page's map count (starts at -1).
                    atomic_set(&page->_mapcount, 0)
                  set_pmd_at
                    // Here we set the page's PMD entry which will be cleared
                    // when Thread A calls pmd_clear_bad().
                  ...
                  spin_unlock(&mm->page_table_lock)

    The mmap_sem does not prevent the race because both threads are acquiring
    it in shared mode (down_read).  Thread B holds the page_table_lock while
    the page's map count and PMD table entry are updated.  However, Thread A
    does not synchronize on that lock.

====== end quote =======

[akpm@linux-foundation.org: checkpatch fixes]
Reported-by: NUlrich Obergfell <uobergfe@redhat.com>
Signed-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Jones <davej@redhat.com>
Acked-by: NLarry Woodman <lwoodman@redhat.com>
Acked-by: NRik van Riel <riel@redhat.com>
Cc: <stable@vger.kernel.org>		[2.6.38+]
Cc: Mark Salter <msalter@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull hwmon changes for v3.4 from Guenter Roeck:
 "Mostly cleanup.  No new drivers this time around, but support for
  several chips added to existing drivers: TPS40400, TPS40422, MTD040,
  MAX34446, ZL9101M, ZL9117M, and LM96080.  Also, added watchdog support
  for SCH56xx, and additional attributes for a couple of drivers."

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (137 commits)
  hwmon: (sch56xx) Add support for the integrated watchdog (v2)
  hwmon: (w83627ehf) Add support for temperature offset registers
  hwmon: (jc42) Remove unnecessary device IDs
  hwmon: (zl6100) Add support for ZL9101M and ZL9117M
  hwmon: (adm1275) Add support for ADM1075
  hwmon: (max34440) Add support for MAX34446
  hwmon: (pmbus) Add more virtual registers
  hwmon: (pmbus) Add support for Lineage Power MDT040
  hwmon: (pmbus) Add support for TI TPS40400 and TPS40422
  hwmon: (max34440) Add support for 'lowest' output voltage attribute
  hwmon: (jc42) Convert to use devm_kzalloc
  hwmon: (max16065) Convert to use devm_kzalloc
  hwmon: (smm665) Convert to use devm_kzalloc
  hwmon: (ltc4261) Convert to use devm_kzalloc
  hwmon: (pmbus) Simplify remove functions
  hwmon: (pmbus) Convert pmbus drivers to use devm_kzalloc
  hwmon: (lineage-pem) Convert to use devm_kzalloc
  hwmon: (hwmon-vid) Fix checkpatch issues
  hwmon: (hwmon-vid) Add new entries to VRM model table
  hwmon: (lm80) Add detection of NatSemi/TI LM96080
  ...

Pull regulator updates for 3.4 from Mark Brown:
 "This has been a fairly quiet release from a regulator point of view,
  the only real framework features added were devm support and a
  convenience helper for setting up fixed voltage regulators.

  We also added a couple of drivers (but will drop the BQ240022 driver
  via the arm-soc tree as it's been replaced by the more generic
  gpio-regulator driver) and Axel Lin continued his relentless and
  generally awesome stream of fixes and cleanups."

* tag 'regulator-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (93 commits)
  regulator: Fix up a confusing dev_warn when DT lookup fails
  regulator: Convert tps6507x to set_voltage_sel
  regulator: Refactor tps6507x to use one tps6507x_pmic_ops for all LDOs and DCDCs
  regulator: Make s5m8767_get_voltage_register always return correct register
  regulator: s5m8767: Check pdata->buck[2|3|4]_gpiodvs earlier
  regulator: tps65910: Provide settling time for DCDC voltage change
  regulator: Add Anatop regulator driver
  regulator: Simplify implementation of tps65912_get_voltage_dcdc
  regulator: Use tps65912_set_voltage_sel for both DCDCx and LDOx
  regulator: tps65910: Provide settling time for enabling rails
  regulator: max8925: Use DIV_ROUND_UP macro
  regulator: tps65912: Use simple equations to get register address
  regulator: Fix the logic of tps65910_get_mode
  regulator: Merge tps65217_pmic_ldo234_ops and tps65217_pmic_dcdc_ops to tps65217_pmic_ops
  regulator: Use DIV_ROUND_CLOSEST in wm8350_isink_get_current
  regulator: Use array to store dcdc_range settings for tps65912
  regulator: Rename s5m8767_convert_voltage to s5m8767_convert_voltage_to_sel
  regulator: tps6524x: Remove unneeded comment for N_REGULATORS
  regulator: Rename set_voltage_sel callback function name to *_sel
  regulator: Fix s5m8767_set_voltage_time_sel calculation value
  ...

Pull InfiniBand/RDMA changes for the 3.4 merge window from Roland Dreier:
 "Nothing big really stands out; by patch count lots of fixes to the
  mlx4 driver plus some cleanups and fixes to the core and other
  drivers."

* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband: (28 commits)
  mlx4_core: Scale size of MTT table with system RAM
  mlx4_core: Allow dynamic MTU configuration for IB ports
  IB/mlx4: Fix info returned when querying IBoE ports
  IB/mlx4: Fix possible missed completion event
  mlx4_core: Report thermal error events
  mlx4_core: Fix one more static exported function
  IB: Change CQE "csum_ok" field to a bit flag
  RDMA/iwcm: Reject connect requests if cmid is not in LISTEN state
  RDMA/cxgb3: Don't pass irq flags to flush_qp()
  mlx4_core: Get rid of redundant ext_port_cap flags
  RDMA/ucma: Fix AB-BA deadlock
  IB/ehca: Fix ilog2() compile failure
  IB: Use central enum for speed instead of hard-coded values
  IB/iser: Post initial receive buffers before sending the final login request
  IB/iser: Free IB connection resources in the proper place
  IB/srp: Consolidate repetitive sysfs code
  IB/srp: Use pr_fmt() and pr_err()/pr_warn()
  IB/core: Fix SDR rates in sysfs
  mlx4: Enforce device max FMR maps in FMR alloc
  IB/mlx4: Set bad_wr for invalid send opcode
  ...

Pull SPI changes for v3.4 from Grant Likely:
 "Mostly a bunch of new drivers and driver bug fixes; but this also
  includes a few patches that create a core message queue infrastructure
  for the spi subsystem instead of making each driver open code it."

* tag 'spi-for-linus' of git://git.secretlab.ca/git/linux-2.6: (34 commits)
  spi/fsl-espi: Make sure pm is within 2..32
  spi/fsl-espi: make the clock computation easier to read
  spi: sh-hspi: modify write/read method
  spi: sh-hspi: control spi clock more correctly
  spi: sh-hspi: convert to using core message queue
  spi: s3c64xx: Fix build
  spi: s3c64xx: remove unnecessary callback msg->complete
  spi: remove redundant variable assignment
  spi: release lock on error path in spi_pump_messages()
  spi: Compatibility with direction which is used in samsung DMA operation
  spi-topcliff-pch: add recovery processing in case wait-event timeout
  spi-topcliff-pch: supports a spi mode setup and bit order setup by IO control
  spi-topcliff-pch: Fix issue for transmitting over 4KByte
  spi-topcliff-pch: Modify pci-bus number dynamically to get DMA device info
  spi/imx: simplify error handling to free gpios
  spi: Convert to DEFINE_PCI_DEVICE_TABLE
  spi: add Broadcom BCM63xx SPI controller driver
  SPI: add CSR SiRFprimaII SPI controller driver
  spi-topcliff-pch: fix -Wuninitialized warning
  spi: Mark spi_register_board_info() __devinit
  ...

Pull core device tree changes for Linux v3.4 from Grant Likely:
 "This branch contains a minor documentation addition, a utility
  function for parsing string properties needed by some of the new ARM
  platforms, disables dynamic DT code that isn't used anywhere but on a
  few PPC machines, and exports DT node compatible data to userspace via
  UEVENT properties.  Nothing earth shattering here."

* tag 'dt-for-linus' of git://git.secretlab.ca/git/linux-2.6:
  of: Only compile OF_DYNAMIC on PowerPC pseries and iseries
  arm/dts: OMAP3: Add omap3evm and am335xevm support
  drivercore: Output common devicetree information in uevent
  of: Add of_property_match_string() to find index into a string list

Pull irq_domain support for all architectures from Grant Likely:
 "Generialize powerpc's irq_host as irq_domain

  This branch takes the PowerPC irq_host infrastructure (reverse mapping
  from Linux IRQ numbers to hardware irq numbering), generalizes it,
  renames it to irq_domain, and makes it available to all architectures.

  Originally the plan has been to create an all-new irq_domain
  implementation which addresses some of the powerpc shortcomings such
  as not handling 1:1 mappings well, but doing that proved to be far
  more difficult and invasive than generalizing the working code and
  refactoring it in-place.  So, this branch rips out the 'new'
  irq_domain and replaces it with the modified powerpc version (in a
  fully bisectable way of course).  It converts all users over to the
  new API and makes irq_domain selectable on any architecture.

  No architecture is forced to enable irq_domain, but the infrastructure
  is required for doing OpenFirmware style irq translations.  It will
  even work on SPARC even though SPARC has it's own mechanism for
  translating irqs at boot time.  MIPS, microblaze, embedded x86 and c6x
  are converted too.

  The resulting irq_domain code is probably still too verbose and can be
  optimized more, but that can be done incrementally and is a task for
  follow-on patches."

* tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6: (31 commits)
  dt: fix twl4030 for non-dt compile on x86
  mfd: twl-core: Add IRQ_DOMAIN dependency
  devicetree: Add empty of_platform_populate() for !CONFIG_OF_ADDRESS (sparc)
  irq_domain: Centralize definition of irq_dispose_mapping()
  irq_domain/mips: Allow irq_domain on MIPS
  irq_domain/x86: Convert x86 (embedded) to use common irq_domain
  ppc-6xx: fix build failure in flipper-pic.c and hlwd-pic.c
  irq_domain/microblaze: Convert microblaze to use irq_domains
  irq_domain/powerpc: Replace custom xlate functions with library functions
  irq_domain/powerpc: constify irq_domain_ops
  irq_domain/c6x: Use library of xlate functions
  irq_domain/c6x: constify irq_domain structures
  irq_domain/c6x: Convert c6x to use generic irq_domain support.
  irq_domain: constify irq_domain_ops
  irq_domain: Create common xlate functions that device drivers can use
  irq_domain: Remove irq_domain_add_simple()
  irq_domain: Remove 'new' irq_domain in favour of the ppc one
  mfd: twl-core.c: Fix the number of interrupts managed by twl4030
  of/address: add empty static inlines for !CONFIG_OF
  irq_domain: Add support for base irq and hwirq in legacy mappings
  ...

Pull power management updates for 3.4 from Rafael Wysocki:
 "Assorted extensions and fixes including:

  * Introduction of early/late suspend/hibernation device callbacks.
  * Generic PM domains extensions and fixes.
  * devfreq updates from Axel Lin and MyungJoo Ham.
  * Device PM QoS updates.
  * Fixes of concurrency problems with wakeup sources.
  * System suspend and hibernation fixes."

* tag 'pm-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (43 commits)
  PM / Domains: Check domain status during hibernation restore of devices
  PM / devfreq: add relation of recommended frequency.
  PM / shmobile: Make MTU2 driver use pm_genpd_dev_always_on()
  PM / shmobile: Make CMT driver use pm_genpd_dev_always_on()
  PM / shmobile: Make TMU driver use pm_genpd_dev_always_on()
  PM / Domains: Introduce "always on" device flag
  PM / Domains: Fix hibernation restore of devices, v2
  PM / Domains: Fix handling of wakeup devices during system resume
  sh_mmcif / PM: Use PM QoS latency constraint
  tmio_mmc / PM: Use PM QoS latency constraint
  PM / QoS: Make it possible to expose PM QoS latency constraints
  PM / Sleep: JBD and JBD2 missing set_freezable()
  PM / Domains: Fix include for PM_GENERIC_DOMAINS=n case
  PM / Freezer: Remove references to TIF_FREEZE in comments
  PM / Sleep: Add more wakeup source initialization routines
  PM / Hibernate: Enable usermodehelpers in hibernate() error path
  PM / Sleep: Make __pm_stay_awake() delete wakeup source timers
  PM / Sleep: Fix race conditions related to wakeup source timer function
  PM / Sleep: Fix possible infinite loop during wakeup source destruction
  PM / Hibernate: print physical addresses consistently with other parts of kernel
  ...

Pull kmap_atomic cleanup from Cong Wang.

It's been in -next for a long time, and it gets rid of the (no longer
used) second argument to k[un]map_atomic().

Fix up a few trivial conflicts in various drivers, and do an "evil
merge" to catch some new uses that have come in since Cong's tree.

* 'kmap_atomic' of git://github.com/congwang/linux: (59 commits)
  feature-removal-schedule.txt: schedule the deprecated form of kmap_atomic() for removal
  highmem: kill all __kmap_atomic() [swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename]
  drbd: remove the second argument of k[un]map_atomic()
  zcache: remove the second argument of k[un]map_atomic()
  gma500: remove the second argument of k[un]map_atomic()
  dm: remove the second argument of k[un]map_atomic()
  tomoyo: remove the second argument of k[un]map_atomic()
  sunrpc: remove the second argument of k[un]map_atomic()
  rds: remove the second argument of k[un]map_atomic()
  net: remove the second argument of k[un]map_atomic()
  mm: remove the second argument of k[un]map_atomic()
  lib: remove the second argument of k[un]map_atomic()
  power: remove the second argument of k[un]map_atomic()
  kdb: remove the second argument of k[un]map_atomic()
  udf: remove the second argument of k[un]map_atomic()
  ubifs: remove the second argument of k[un]map_atomic()
  squashfs: remove the second argument of k[un]map_atomic()
  reiserfs: remove the second argument of k[un]map_atomic()
  ocfs2: remove the second argument of k[un]map_atomic()
  ntfs: remove the second argument of k[un]map_atomic()
  ...

Pull trivial tree from Jiri Kosina:
 "It's indeed trivial -- mostly documentation updates and a bunch of
  typo fixes from Masanari.

  There are also several linux/version.h include removals from Jesper."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (101 commits)
  kcore: fix spelling in read_kcore() comment
  constify struct pci_dev * in obvious cases
  Revert "char: Fix typo in viotape.c"
  init: fix wording error in mm_init comment
  usb: gadget: Kconfig: fix typo for 'different'
  Revert "power, max8998: Include linux/module.h just once in drivers/power/max8998_charger.c"
  writeback: fix fn name in writeback_inodes_sb_nr_if_idle() comment header
  writeback: fix typo in the writeback_control comment
  Documentation: Fix multiple typo in Documentation
  tpm_tis: fix tis_lock with respect to RCU
  Revert "media: Fix typo in mixer_drv.c and hdmi_drv.c"
  Doc: Update numastat.txt
  qla4xxx: Add missing spaces to error messages
  compiler.h: Fix typo
  security: struct security_operations kerneldoc fix
  Documentation: broken URL in libata.tmpl
  Documentation: broken URL in filesystems.tmpl
  mtd: simplify return logic in do_map_probe()
  mm: fix comment typo of truncate_inode_pages_range
  power: bq27x00: Fix typos in comment
  ...

Pull HID updates from Jiri Kosina:
 "It contains HID driver updates all over the place -- a lot of new
  hardware support especially in the multitouch area, including generic
  handling of all multitouch devices by the hid-multitiouch driver
  automatically."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (42 commits)
  HID: multitouch: add PID for Fructel product
  HID: wacom: Add reporting of wheel for Intuos4 WL
  HID: wacom: Replace __set_bit with input_set_capability
  HID: tivo: add support for BT-version (0x1200)
  HID: wacom: Reset stylus buttons - Intuos4 WL
  HID: multitouch: detect serial protocol
  HID: handle all multitouch devices through hid-multitouch
  HID: multitouch: fix handling of buggy reports descriptors for Dell ST2220T
  HID: make it possible to force hid-core claim the device
  HID: multitouch: add support for eGalax 0x722a
  HID: usbhid: add quirk no_get for quanta 3008 devices
  HID: multitouch: add more eGalax devices
  HID: multitouch: add new PID from Ideacom
  HID: multitouch: add support for Atmel maXTouch 03eb:2118
  HID: waltop: Add support for tablet with PID 0038
  HID: waltop: Replace original rdescs with links
  HID: uclogic: Replace original rdescs with links
  HID: wacom: Add pad buttons reporting on Intuos4 WL
  HID: wacom: report distance for Intuos4 WL
  HID: kye: Add support for 3 tablets
  ...

Pull networking merge from David Miller:
 "1) Move ixgbe driver over to purely page based buffering on receive.
     From Alexander Duyck.

  2) Add receive packet steering support to e1000e, from Bruce Allan.

  3) Convert TCP MD5 support over to RCU, from Eric Dumazet.

  4) Reduce cpu usage in handling out-of-order TCP packets on modern
     systems, also from Eric Dumazet.

  5) Support the IP{,V6}_UNICAST_IF socket options, making the wine
     folks happy, from Erich Hoover.

  6) Support VLAN trunking from guests in hyperv driver, from Haiyang
     Zhang.

  7) Support byte-queue-limtis in r8169, from Igor Maravic.

  8) Outline code intended for IP_RECVTOS in IP_PKTOPTIONS existed but
     was never properly implemented, Jiri Benc fixed that.

  9) 64-bit statistics support in r8169 and 8139too, from Junchang Wang.

  10) Support kernel side dump filtering by ctmark in netfilter
      ctnetlink, from Pablo Neira Ayuso.

  11) Support byte-queue-limits in gianfar driver, from Paul Gortmaker.

  12) Add new peek socket options to assist with socket migration, from
      Pavel Emelyanov.

  13) Add sch_plug packet scheduler whose queue is controlled by
      userland daemons using explicit freeze and release commands.  From
      Shriram Rajagopalan.

  14) Fix FCOE checksum offload handling on transmit, from Yi Zou."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1846 commits)
  Fix pppol2tp getsockname()
  Remove printk from rds_sendmsg
  ipv6: fix incorrent ipv6 ipsec packet fragment
  cpsw: Hook up default ndo_change_mtu.
  net: qmi_wwan: fix build error due to cdc-wdm dependecy
  netdev: driver: ethernet: Add TI CPSW driver
  netdev: driver: ethernet: add cpsw address lookup engine support
  phy: add am79c874 PHY support
  mlx4_core: fix race on comm channel
  bonding: send igmp report for its master
  fs_enet: Add MPC5125 FEC support and PHY interface selection
  net: bpf_jit: fix BPF_S_LDX_B_MSH compilation
  net: update the usage of CHECKSUM_UNNECESSARY
  fcoe: use CHECKSUM_UNNECESSARY instead of CHECKSUM_PARTIAL on tx
  net: do not do gso for CHECKSUM_UNNECESSARY in netif_needs_gso
  ixgbe: Fix issues with SR-IOV loopback when flow control is disabled
  net/hyperv: Fix the code handling tx busy
  ixgbe: fix namespace issues when FCoE/DCB is not enabled
  rtlwifi: Remove unused ETH_ADDR_LEN defines
  igbvf: Use ETH_ALEN
  ...

Fix up fairly trivial conflicts in drivers/isdn/gigaset/interface.c and
drivers/net/usb/{Kconfig,qmi_wwan.c} as per David.

Pull workqueue changes from Tejun Heo:
 "This contains only one commit which cleans up UP allocation path a
  bit."

* 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: use percpu allocator for cwq on UP

Pull cgroup changes from Tejun Heo:
 "Out of the 8 commits, one fixes a long-standing locking issue around
  tasklist walking and others are cleanups."

* 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: Walk task list under tasklist_lock in cgroup_enable_task_cg_list
  cgroup: Remove wrong comment on cgroup_enable_task_cg_list()
  cgroup: remove cgroup_subsys argument from callbacks
  cgroup: remove extra calls to find_existing_css_set
  cgroup: replace tasklist_lock with rcu_read_lock
  cgroup: simplify double-check locking in cgroup_attach_proc
  cgroup: move struct cgroup_pidlist out from the header file
  cgroup: remove cgroup_attach_task_current_cg()

Minor cleanup. de_thread()->setmax_mm_hiwater_rss() looks a bit
strange, move it into exec_mmap() which plays with old_mm.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

exit_notify() changes ->exit_signal if the parent already did exec.
This doesn't really work, we are not going to send the signal now
if there is another live thread or the exiting task is traced. The
parent can exec before the last dies or the tracer detaches.

Move this check into do_notify_parent() which actually sends the
signal.

The user-visible change is that we do not change ->exit_signal,
and thus the exiting task is still "clone children" for
do_wait()->eligible_child(__WCLONE). Hopefully this is fine, the
current logic is racy anyway.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

exit_notify() checks "tsk->self_exec_id != tsk->parent_exec_id"
to handle the "we have changed execution domain" case.

We can change do_thread() to always set ->exit_signal = SIGCHLD
and remove this check to simplify the code.

We could change setup_new_exec() instead, this looks more logical
because it increments ->self_exec_id. But note that de_thread()
already resets ->exit_signal if it changes the leader, let's keep
both changes close to each other.

Note that we change ->exit_signal lockless, this changes the rules.
Thereafter ->exit_signal is not stable under tasklist but this is
fine, the only possible change is OLDSIG -> SIGCHLD. This can race
with eligible_child() but the race is harmless. We can race with
reparent_leader() which changes our ->exit_signal in parallel, but
it does the same change to SIGCHLD.

The noticeable user-visible change is that the execing task is not
"visible" to do_wait()->eligible_child(__WCLONE) right after exec.
To me this looks more logical, and this is consistent with mt case.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The child must not control its ->exit_signal, it is the parent who
decides which signal the child should use for notification.

This means that CLONE_PARENT should not use "clone_flags & CSIGNAL",
the forking task is the sibling of the new process and their parent
doesn't control exit_signal in this case.

This patch uses ->exit_signal of the forking process, but perhaps
we should simply use SIGCHLD.

We read group_leader->exit_signal lockless, this can race with the
ORIGINAL_SIGNAL -> SIGCHLD transition, but this is fine.

Potentially this change allows to kill self_exec_id/parent_exec_id.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

While testing L2TP functionality, I came across a bug in getsockname().  The
IP address returned within the pppol2tp_addr's addr memember was not being
set to the IP  address in use.  This bug is caused by using inet_sk() on the
wrong socket (the L2TP socket rather than the underlying UDP socket), and was
likely introduced during the addition of L2TPv3 support.
Signed-off-by: NBenjamin LaHaise <bcrl@kvack.org>
Signed-off-by: NJames Chapman <jchapman@katalix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

no socket layer outputs a message for this error and neither should rds.
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull USB merge for 3.4-rc1 from Greg KH:
 "Here's the big USB merge for the 3.4-rc1 merge window.

  Lots of gadget driver reworks here, driver updates, xhci changes, some
  new drivers added, usb-serial core reworking to fix some bugs, and
  other various minor things.

  There are some patches touching arch code, but they have all been
  acked by the various arch maintainers."

* tag 'usb-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (302 commits)
  net: qmi_wwan: add support for ZTE MF820D
  USB: option: add ZTE MF820D
  usb: gadget: f_fs: Remove lock is held before freeing checks
  USB: option: make interface blacklist work again
  usb/ub: deprecate & schedule for removal the "Low Performance USB Block" driver
  USB: ohci-pxa27x: add clk_prepare/clk_unprepare calls
  USB: use generic platform driver on ath79
  USB: EHCI: Add a generic platform device driver
  USB: OHCI: Add a generic platform device driver
  USB: ftdi_sio: new PID: LUMEL PD12
  USB: ftdi_sio: add support for FT-X series devices
  USB: serial: mos7840: Fixed MCS7820 device attach problem
  usb: Don't make USB_ARCH_HAS_{XHCI,OHCI,EHCI} depend on USB_SUPPORT.
  usb gadget: fix a section mismatch when compiling g_ffs with CONFIG_USB_FUNCTIONFS_ETH
  USB: ohci-nxp: Remove i2c_write(), use smbus
  USB: ohci-nxp: Support for LPC32xx
  USB: ohci-nxp: Rename symbols from pnx4008 to nxp
  USB: OHCI-HCD: Rename ohci-pnx4008 to ohci-nxp
  usb: gadget: Kconfig: fix typo for 'different'
  usb: dwc3: pci: fix another failure path in dwc3_pci_probe()
  ...

Pull TTY/serial patches from Greg KH:
 "tty and serial merge for 3.4-rc1

  Here's the big serial and tty merge for the 3.4-rc1 tree.

  There's loads of fixes and reworks in here from Jiri for the tty
  layer, and a number of patches from Alan to help try to wrestle the vt
  layer into a sane model.

  Other than that, lots of driver updates and fixes, and other minor
  stuff, all detailed in the shortlog."

* tag 'tty-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (132 commits)
  serial: pxa: add clk_prepare/clk_unprepare calls
  TTY: Wrong unicode value copied in con_set_unimap()
  serial: PL011: clear pending interrupts
  serial: bfin-uart: Don't access tty circular buffer in TX DMA interrupt after it is reset.
  vt: NULL dereference in vt_do_kdsk_ioctl()
  tty: serial: vt8500: fix annotations for probe/remove
  serial: remove back and forth conversions in serial_out_sync
  serial: use serial_port_in/out vs serial_in/out in 8250
  serial: introduce generic port in/out helpers
  serial: reduce number of indirections in 8250 code
  serial: delete useless void casts in 8250.c
  serial: make 8250's serial_in shareable to other drivers.
  serial: delete last unused traces of pausing I/O in 8250
  pch_uart: Add module parameter descriptions
  pch_uart: Use existing default_baud in setup_console
  pch_uart: Add user_uartclk parameter
  pch_uart: Add Fish River Island II uart clock quirks
  pch_uart: Use uartclk instead of base_baud
  mpc5200b/uart: select more tolerant uart prescaler on low baudrates
  tty: moxa: fix bit test in moxa_start()
  ...

Pull big staging driver updates from Greg KH:
 "Here is the big drivers/staging/ merge for 3.4-rc1

  Lots of new driver updates here, with the addition of a few new ones,
  and only one moving out of the staging tree to the "real" part of the
  kernel (the hyperv scsi driver, acked by the scsi maintainer).

  There are also loads of cleanups, fixes, and other minor things in
  here, all self-contained in the drivers/staging/ tree.

  Overall we reversed the recent trend by adding more lines than we
  removed:
   379 files changed, 37952 insertions(+), 14153 deletions(-)"

* tag 'staging-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (360 commits)
  staging/zmem: Use lockdep_assert_held instead of spin_is_locked
  Staging: rtl8187se: r8180_wx.c: Cleaned up comments
  Staging: rtl8187se: r8180_wx.c: Removed old comments
  Staging: rtl8187se: r8180_dm.c: Removed old comments
  Staging: android: ram_console.c:
  Staging: rtl8187se: r8180_dm.c: Fix comments
  Staging: rtl8187se: r8180_dm.c: Fix spacing issues
  Staging: rtl8187se: r8180_dm.c Fixed indentation issues
  Staging: rtl8187se: r8180_dm.c: Fix brackets
  Staging: rtl8187se: r8180_dm.c: Removed spaces before tab stop
  staging: vme: fix section mismatches in linux-next 20120314
  Staging: rtl8187se: r8180_core.c: Fix some long line issues
  Staging: rtl8187se: r8180_core.c: Fix some spacing issues
  Staging: rtl8187se: r8180_core.c: Removed trailing spaces
  staging: mei: remove driver internal versioning
  Staging: rtl8187se: r8180_core.c: Cleaned up if statement
  staging: ozwpan depends on NET
  staging: ozwpan: added maintainer for ozwpan driver
  staging/mei: propagate error codes up in the write flow
  drivers:staging:mei Fix some typos in staging/mei
  ...

Pull driver core patches for 3.4-rc1 from Greg KH:
 "Here's the big driver core merge for 3.4-rc1.

  Lots of various things here, sysfs fixes/tweaks (with the nlink
  breakage reverted), dynamic debugging updates, w1 drivers, hyperv
  driver updates, and a variety of other bits and pieces, full
  information in the shortlog."

* tag 'driver-core-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (78 commits)
  Tools: hv: Support enumeration from all the pools
  Tools: hv: Fully support the new KVP verbs in the user level daemon
  Drivers: hv: Support the newly introduced KVP messages in the driver
  Drivers: hv: Add new message types to enhance KVP
  regulator: Support driver probe deferral
  Revert "sysfs: Kill nlink counting."
  uevent: send events in correct order according to seqnum (v3)
  driver core: minor comment formatting cleanups
  driver core: move the deferred probe pointer into the private area
  drivercore: Add driver probe deferral mechanism
  DS2781 Maxim Stand-Alone Fuel Gauge battery and w1 slave drivers
  w1_bq27000: Only one thread can access the bq27000 at a time.
  w1_bq27000 - remove w1_bq27000_write
  w1_bq27000: remove unnecessary NULL test.
  sysfs: Fix memory leak in sysfs_sd_setsecdata().
  intel_idle: Revert change of auto_demotion_disable_flags for Nehalem
  w1: Fix w1_bq27000
  driver-core: documentation: fix up Greg's email address
  powernow-k6: Really enable auto-loading
  powernow-k7: Fix CPU family number
  ...

Pull char and misc patches for 3.4-rc1 from Greg KH:
 "Not much here, just a few minor fixes and some conversions to the
  module_*_driver() functions, making the codebase smaller."

* tag 'char-misc-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  misc: bmp085: Use unsigned long to store jiffies
  char/ramoops: included linux/err.h twice
  misc: bmp085: Handle jiffies overflow correctly
  misc: fsa9480: Remove obsolete cleanup for clientdata
  char: Fix typo in tlclk.c
  char: Fix typo in viotape.c
  cs5535-mfgpt: don't call __init function from __devinit
  MISC: convert drivers/misc/* to use module_spi_driver()
  MISC: convert drivers/misc/* to use module_i2c_driver()
  MISC: convert drivers/misc/* to use module_platform_driver()

We should be testing "if (vnode->flags & (1 << 4))" instead of
"if (vnode->flags & 4) {".  The current test checks if the data was
modified instead of deleted.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull timer changes for v3.4 from Ingo Molnar

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
  ntp: Fix integer overflow when setting time
  math: Introduce div64_long
  cs5535-clockevt: Allow the MFGPT IRQ to be shared
  cs5535-clockevt: Don't ignore MFGPT on SMP-capable kernels
  x86/time: Eliminate unused irq0_irqs counter
  clocksource: scx200_hrt: Fix the build
  x86/tsc: Reduce the TSC sync check time for core-siblings
  timer: Fix bad idle check on irq entry
  nohz: Remove ts->Einidle checks before restarting the tick
  nohz: Remove update_ts_time_stat from tick_nohz_start_idle
  clockevents: Leave the broadcast device in shutdown mode when not needed
  clocksource: Load the ACPI PM clocksource asynchronously
  clocksource: scx200_hrt: Convert scx200 to use clocksource_register_hz
  clocksource: Get rid of clocksource_calc_mult_shift()
  clocksource: dbx500: convert to clocksource_register_hz()
  clocksource: scx200_hrt:  use pr_<level> instead of printk
  time: Move common updates to a function
  time: Reorder so the hot data is together
  time: Remove most of xtime_lock usage in timekeeping.c
  ntp: Add ntp_lock to replace xtime_locking
  ...

Pull scheduler changes for v3.4 from Ingo Molnar

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  printk: Make it compile with !CONFIG_PRINTK
  sched/x86: Fix overflow in cyc2ns_offset
  sched: Fix nohz load accounting -- again!
  sched: Update yield() docs
  printk/sched: Introduce special printk_sched() for those awkward moments
  sched/nohz: Correctly initialize 'next_balance' in 'nohz' idle balancer
  sched: Cleanup cpu_active madness
  sched: Fix load-balance wreckage
  sched: Clean up parameter passing of proc_sched_autogroup_set_nice()
  sched: Ditch per cgroup task lists for load-balancing
  sched: Rename load-balancing fields
  sched: Move load-balancing arguments into helper struct
  sched/rt: Do not submit new work when PI-blocked
  sched/rt: Prevent idle task boosting
  sched/wait: Add __wake_up_all_locked() API
  sched/rt: Document scheduler related skip-resched-check sites
  sched/rt: Use schedule_preempt_disabled()
  sched/rt: Add schedule_preempt_disabled()
  sched/rt: Do not throttle when PI boosting
  sched/rt: Keep period timer ticking when rt throttling is active
  ...

Pull perf events changes for v3.4 from Ingo Molnar:

 - New "hardware based branch profiling" feature both on the kernel and
   the tooling side, on CPUs that support it.  (modern x86 Intel CPUs
   with the 'LBR' hardware feature currently.)

   This new feature is basically a sophisticated 'magnifying glass' for
   branch execution - something that is pretty difficult to extract from
   regular, function histogram centric profiles.

   The simplest mode is activated via 'perf record -b', and the result
   looks like this in perf report:

	$ perf record -b any_call,u -e cycles:u branchy

	$ perf report -b --sort=symbol
	    52.34%  [.] main                   [.] f1
	    24.04%  [.] f1                     [.] f3
	    23.60%  [.] f1                     [.] f2
	     0.01%  [k] _IO_new_file_xsputn    [k] _IO_file_overflow
	     0.01%  [k] _IO_vfprintf_internal  [k] _IO_new_file_xsputn
	     0.01%  [k] _IO_vfprintf_internal  [k] strchrnul
	     0.01%  [k] __printf               [k] _IO_vfprintf_internal
	     0.01%  [k] main                   [k] __printf

   This output shows from/to branch columns and shows the highest
   percentage (from,to) jump combinations - i.e.  the most likely taken
   branches in the system.  "branches" can also include function calls
   and any other synchronous and asynchronous transitions of the
   instruction pointer that are not 'next instruction' - such as system
   calls, traps, interrupts, etc.

   This feature comes with (hopefully intuitive) flat ascii and TUI
   support in perf report.

 - Various 'perf annotate' visual improvements for us assembly junkies.
   It will now recognize function calls in the TUI and by hitting enter
   you can follow the call (recursively) and back, amongst other
   improvements.

 - Multiple threads/processes recording support in perf record, perf
   stat, perf top - which is activated via a comma-list of PIDs:

	perf top -p 21483,21485
	perf stat -p 21483,21485 -ddd
	perf record -p 21483,21485

 - Support for per UID views, via the --uid paramter to perf top, perf
   report, etc.  For example 'perf top --uid mingo' will only show the
   tasks that I am running, excluding other users, root, etc.

 - Jump label restructurings and improvements - this includes the
   factoring out of the (hopefully much clearer) include/linux/static_key.h
   generic facility:

	struct static_key key = STATIC_KEY_INIT_FALSE;

	...

	if (static_key_false(&key))
	        do unlikely code
	else
	        do likely code

	...
	static_key_slow_inc();
	...
	static_key_slow_inc();
	...

   The static_key_false() branch will be generated into the code with as
   little impact to the likely code path as possible.  the
   static_key_slow_*() APIs flip the branch via live kernel code patching.

   This facility can now be used more widely within the kernel to
   micro-optimize hot branches whose likelihood matches the static-key
   usage and fast/slow cost patterns.

 - SW function tracer improvements: perf support and filtering support.

 - Various hardenings of the perf.data ABI, to make older perf.data's
   smoother on newer tool versions, to make new features integrate more
   smoothly, to support cross-endian recording/analyzing workflows
   better, etc.

 - Restructuring of the kprobes code, the splitting out of 'optprobes',
   and a corner case bugfix.

 - Allow the tracing of kernel console output (printk).

 - Improvements/fixes to user-space RDPMC support, allowing user-space
   self-profiling code to extract PMU counts without performing any
   system calls, while playing nice with the kernel side.

 - 'perf bench' improvements

 - ... and lots of internal restructurings, cleanups and fixes that made
   these features possible.  And, as usual this list is incomplete as
   there were also lots of other improvements

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits)
  perf report: Fix annotate double quit issue in branch view mode
  perf report: Remove duplicate annotate choice in branch view mode
  perf/x86: Prettify pmu config literals
  perf report: Enable TUI in branch view mode
  perf report: Auto-detect branch stack sampling mode
  perf record: Add HEADER_BRANCH_STACK tag
  perf record: Provide default branch stack sampling mode option
  perf tools: Make perf able to read files from older ABIs
  perf tools: Fix ABI compatibility bug in print_event_desc()
  perf tools: Enable reading of perf.data files from different ABI rev
  perf: Add ABI reference sizes
  perf report: Add support for taken branch sampling
  perf record: Add support for sampling taken branch
  perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK
  x86/kprobes: Split out optprobe related code to kprobes-opt.c
  x86/kprobes: Fix a bug which can modify kernel code permanently
  x86/kprobes: Fix instruction recovery on optimized path
  perf: Add callback to flush branch_stack on context switch
  perf: Disable PERF_SAMPLE_BRANCH_* when not supported
  perf/x86: Add LBR software filter support for Intel CPUs
  ...

Pull irq/core changes for v3.4 from Ingo Molnar

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Remove paranoid warnons and bogus fixups
  genirq: Flush the irq thread on synchronization
  genirq: Get rid of unnecessary IRQTF_DIED flag
  genirq: No need to check IRQTF_DIED before stopping a thread handler
  genirq: Get rid of unnecessary irqaction field in task_struct
  genirq: Fix incorrect check for forced IRQ thread handler
  softirq: Reduce invoke_softirq() code duplication
  genirq: Fix long-term regression in genirq irq_set_irq_type() handling
  x86-32/irq: Don't switch to irq stack for a user-mode irq

Pull RCU changes for v3.4 from Ingo Molnar.  The major features of this
series are:

 - making RCU more aggressive about entering dyntick-idle mode in order
   to improve energy efficiency

 - converting a few more call_rcu()s to kfree_rcu()s

 - applying a number of rcutree fixes and cleanups to rcutiny

 - removing CONFIG_SMP #ifdefs from treercu

 - allowing RCU CPU stall times to be set via sysfs

 - adding CPU-stall capability to rcutorture

 - adding more RCU-abuse diagnostics

 - updating documentation

 - fixing yet more issues located by the still-ongoing top-to-bottom
   inspection of RCU, this time with a special focus on the CPU-hotplug
   code path.

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
  rcu: Stop spurious warnings from synchronize_sched_expedited
  rcu: Hold off RCU_FAST_NO_HZ after timer posted
  rcu: Eliminate softirq-mediated RCU_FAST_NO_HZ idle-entry loop
  rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sections
  rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit()
  rcu: Remove redundant check for rcu_head misalignment
  PTR_ERR should be called before its argument is cleared.
  rcu: Convert WARN_ON_ONCE() in rcu_lock_acquire() to lockdep
  rcu: Trace only after NULL-pointer check
  rcu: Call out dangers of expedited RCU primitives
  rcu: Rework detection of use of RCU by offline CPUs
  lockdep: Add CPU-idle/offline warning to lockdep-RCU splat
  rcu: No interrupt disabling for rcu_prepare_for_idle()
  rcu: Move synchronize_sched_expedited() to rcutree.c
  rcu: Check for illegal use of RCU from offlined CPUs
  rcu: Update stall-warning documentation
  rcu: Add CPU-stall capability to rcutorture
  rcu: Make documentation give more realistic rcutorture duration
  rcutorture: Permit holding off CPU-hotplug operations during boot
  rcu: Print scheduling-clock information on RCU CPU stall-warning messages
  ...

Signed-off-by: NCong Wang <amwang@redhat.com>

[swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename]
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NCong Wang <amwang@redhat.com>

Signed-off-by: NCong Wang <amwang@redhat.com>

Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NCong Wang <amwang@redhat.com>

Signed-off-by: NCong Wang <amwang@redhat.com>

Acked-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NCong Wang <amwang@redhat.com>