1. 26 Nov, 2014 1 commit
  2. 25 Nov, 2014 29 commits
    • Wolfram Sang's avatar
      i2c: at91: don't account as iowait · 0e16b1c3
      Wolfram Sang authored
      commit 11cfbfb0 upstream.
      
      iowait is for blkio [1]. I2C shouldn't use it.
      
      [1] https://lkml.org/lkml/2014/11/3/317Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
      Acked-by: default avatarLudovic Desroches <ludovic.desroches@atmel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      0e16b1c3
    • Yijing Wang's avatar
      sysfs: driver core: Fix glue dir race condition by gdp_mutex · 88ae6682
      Yijing Wang authored
      commit e4a60d13 upstream.
      
      There is a race condition when removing glue directory.
      It can be reproduced in following test:
      
      path 1: Add first child device
      device_add()
          get_device_parent()
                  /*find parent from glue_dirs.list*/
                  list_for_each_entry(k, &dev->class->p->glue_dirs.list, entry)
                          if (k->parent == parent_kobj) {
                                  kobj = kobject_get(k);
                                  break;
                          }
                  ....
                  class_dir_create_and_add()
      
      path2: Remove last child device under glue dir
      device_del()
          cleanup_device_parent()
                  cleanup_glue_dir()
                          kobject_put(glue_dir);
      
      If path2 has been called cleanup_glue_dir(), but not
      call kobject_put(glue_dir), the glue dir is still
      in parent's kset list. Meanwhile, path1 find the glue
      dir from the glue_dirs.list. Path2 may release glue dir
      before path1 call kobject_get(). So kernel will report
      the warning and bug_on.
      
      This is a "classic" problem we have of a kref in a list
      that can be found while the last instance could be removed
      at the same time.
      
      This patch reuse gdp_mutex to fix this race condition.
      
      The following calltrace is captured in kernel 3.4, but
      the latest kernel still has this bug.
      
      -----------------------------------------------------
      <4>[ 3965.441471] WARNING: at ...include/linux/kref.h:41 kobject_get+0x33/0x40()
      <4>[ 3965.441474] Hardware name: Romley
      <4>[ 3965.441475] Modules linked in: isd_iop(O) isd_xda(O)...
      ...
      <4>[ 3965.441605] Call Trace:
      <4>[ 3965.441611]  [<ffffffff8103717a>] warn_slowpath_common+0x7a/0xb0
      <4>[ 3965.441615]  [<ffffffff810371c5>] warn_slowpath_null+0x15/0x20
      <4>[ 3965.441618]  [<ffffffff81215963>] kobject_get+0x33/0x40
      <4>[ 3965.441624]  [<ffffffff812d1e45>] get_device_parent.isra.11+0x135/0x1f0
      <4>[ 3965.441627]  [<ffffffff812d22d4>] device_add+0xd4/0x6d0
      <4>[ 3965.441631]  [<ffffffff812d0dbc>] ? dev_set_name+0x3c/0x40
      ....
      <2>[ 3965.441912] kernel BUG at ..../fs/sysfs/group.c:65!
      <4>[ 3965.441915] invalid opcode: 0000 [#1] SMP
      ...
      <4>[ 3965.686743]  [<ffffffff811a677e>] sysfs_create_group+0xe/0x10
      <4>[ 3965.686748]  [<ffffffff810cfb04>] blk_trace_init_sysfs+0x14/0x20
      <4>[ 3965.686753]  [<ffffffff811fcabb>] blk_register_queue+0x3b/0x120
      <4>[ 3965.686756]  [<ffffffff812030bc>] add_disk+0x1cc/0x490
      ....
      -------------------------------------------------------
      Signed-off-by: default avatarYijing Wang <wangyijing@huawei.com>
      Signed-off-by: default avatarWeng Meiling <wengmeiling.weng@huawei.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      88ae6682
    • Dmitry Eremin-Solenikov's avatar
      spi: pxa2xx: toggle clocks on suspend if not disabled by runtime PM · 219b731d
      Dmitry Eremin-Solenikov authored
      commit 2b9375b9 upstream.
      
      If PM_RUNTIME is enabled, it is easy to trigger the following backtrace
      on pxa2xx hosts:
      
      ------------[ cut here ]------------
      WARNING: CPU: 0 PID: 1 at /home/lumag/linux/arch/arm/mach-pxa/clock.c:35 clk_disable+0xa0/0xa8()
      Modules linked in:
      CPU: 0 PID: 1 Comm: swapper Not tainted 3.17.0-00007-g1b3d2ee-dirty #104
      [<c000de68>] (unwind_backtrace) from [<c000c078>] (show_stack+0x10/0x14)
      [<c000c078>] (show_stack) from [<c001d75c>] (warn_slowpath_common+0x6c/0x8c)
      [<c001d75c>] (warn_slowpath_common) from [<c001d818>] (warn_slowpath_null+0x1c/0x24)
      [<c001d818>] (warn_slowpath_null) from [<c0015e80>] (clk_disable+0xa0/0xa8)
      [<c0015e80>] (clk_disable) from [<c02507f8>] (pxa2xx_spi_suspend+0x2c/0x34)
      [<c02507f8>] (pxa2xx_spi_suspend) from [<c0200360>] (platform_pm_suspend+0x2c/0x54)
      [<c0200360>] (platform_pm_suspend) from [<c0207fec>] (dpm_run_callback.isra.14+0x2c/0x74)
      [<c0207fec>] (dpm_run_callback.isra.14) from [<c0209254>] (__device_suspend+0x120/0x2f8)
      [<c0209254>] (__device_suspend) from [<c0209a94>] (dpm_suspend+0x50/0x208)
      [<c0209a94>] (dpm_suspend) from [<c00455ac>] (suspend_devices_and_enter+0x8c/0x3a0)
      [<c00455ac>] (suspend_devices_and_enter) from [<c0045ad4>] (pm_suspend+0x214/0x2a8)
      [<c0045ad4>] (pm_suspend) from [<c04b5c34>] (test_suspend+0x14c/0x1dc)
      [<c04b5c34>] (test_suspend) from [<c000880c>] (do_one_initcall+0x8c/0x1fc)
      [<c000880c>] (do_one_initcall) from [<c04aecfc>] (kernel_init_freeable+0xf4/0x1b4)
      [<c04aecfc>] (kernel_init_freeable) from [<c0378078>] (kernel_init+0x8/0xec)
      [<c0378078>] (kernel_init) from [<c0009590>] (ret_from_fork+0x14/0x24)
      ---[ end trace 46524156d8faa4f6 ]---
      
      This happens because suspend function tries to disable a clock that is
      already disabled by runtime_suspend callback. Add if
      (!pm_runtime_suspended()) checks to suspend/resume path.
      
      Fixes: 7d94a505 (spi/pxa2xx: add support for runtime PM)
      Signed-off-by: default avatarDmitry Eremin-Solenikov <dbaryshkov@gmail.com>
      Reported-by: default avatarAndrea Adami <andrea.adami@gmail.com>
      Signed-off-by: default avatarMark Brown <broonie@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      219b731d
    • Imre Deak's avatar
      tty/vt: don't set font mappings on vc not supporting this · c00b3bcf
      Imre Deak authored
      commit 9e326f78 upstream.
      
      We can call this function for a dummy console that doesn't support
      setting the font mapping, which will result in a null ptr BUG. So check
      for this case and return error for consoles w/o font mapping support.
      
      Reference: https://bugzilla.kernel.org/show_bug.cgi?id=59321Signed-off-by: default avatarImre Deak <imre.deak@intel.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      [ kamal: backport to 3.13-stable: context ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c00b3bcf
    • Peter Hurley's avatar
      tty: Prevent "read/write wait queue active!" log flooding · a834e6e1
      Peter Hurley authored
      commit 494c1eac upstream.
      
      Only print one warning when a task is on the read_wait or write_wait
      wait queue at final tty release.
      Signed-off-by: default avatarPeter Hurley <peter@hurleysoftware.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      a834e6e1
    • Peter Hurley's avatar
      tty: Fix high cpu load if tty is unreleaseable · 9211a96f
      Peter Hurley authored
      commit 37b16457 upstream.
      
      Kernel oops can cause the tty to be unreleaseable (for example, if
      n_tty_read() crashes while on the read_wait queue). This will cause
      tty_release() to endlessly loop without sleeping.
      
      Use a killable sleep timeout which grows by 2n+1 jiffies over the interval
      [0, 120 secs.) and then jumps to forever (but still killable).
      
      NB: killable just allows for the task to be rewoken manually, not
      to be terminated.
      Signed-off-by: default avatarPeter Hurley <peter@hurleysoftware.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      9211a96f
    • Peter Hurley's avatar
      serial: Fix divide-by-zero fault in uart_get_divisor() · c789c9c1
      Peter Hurley authored
      commit 547039ec upstream.
      
      uart_get_baud_rate() will return baud == 0 if the max rate is set
      to the "magic" 38400 rate and the SPD_* flags are also specified.
      On the first iteration, if the current baud rate is higher than the
      max, the baud rate is clamped at the max (which in the degenerate
      case is 38400). On the second iteration, the now-"magic" 38400 baud
      rate selects the possibly higher alternate baud rate indicated by
      the SPD_* flag. Since only two loop iterations are performed, the
      loop is exited, a kernel WARNING is generated and a baud rate of
      0 is returned.
      
      Reproducible with:
       setserial /dev/ttyS0 spd_hi base_baud 38400
      
      Only perform the "magic" 38400 -> SPD_* baud transform on the first
      loop iteration, which prevents the degenerate case from recognizing
      the clamped baud rate as the "magic" 38400 value.
      Reported-by: default avatarRobert Święcki <robert@swiecki.net>
      Signed-off-by: default avatarPeter Hurley <peter@hurleysoftware.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c789c9c1
    • Johan Hovold's avatar
      USB: cdc-acm: only raise DTR on transitions from B0 · 38fb49c4
      Johan Hovold authored
      commit 4473d054 upstream.
      
      Make sure to only raise DTR on transitions from B0 in set_termios.
      
      Also allow set_termios to be called from open with a termios_old of
      NULL. Note that DTR will not be raised prematurely in this case.
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      38fb49c4
    • Lars-Peter Clausen's avatar
      staging:iio:ade7758: Remove "raw" from channel name · 00ef66a0
      Lars-Peter Clausen authored
      commit b598aacc upstream.
      
      "raw" is a property of a channel, but should not be part of the name of
      channel.
      Signed-off-by: default avatarLars-Peter Clausen <lars@metafoo.de>
      Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      00ef66a0
    • Lars-Peter Clausen's avatar
      staging:iio:ade7758: Fix check if channels are enabled in prenable · 8060fe6d
      Lars-Peter Clausen authored
      commit 79fa64eb upstream.
      
      We should check if a channel is enabled, not if no channels are enabled.
      
      Fixes: 550268ca ("staging:iio: scrap scan_count and ensure all drivers use active_scan_mask")
      Signed-off-by: default avatarLars-Peter Clausen <lars@metafoo.de>
      Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      8060fe6d
    • Lars-Peter Clausen's avatar
      staging:iio:ade7758: Fix NULL pointer deref when enabling buffer · ef5b2e4d
      Lars-Peter Clausen authored
      commit e1055473 upstream.
      
      In older versions of the IIO framework it was possible to pass a completely
      different set of channels to iio_buffer_register() as the one that is
      assigned to the IIO device. Commit 959d2952 ("staging:iio: make
      iio_sw_buffer_preenable much more general.") introduced a restriction that
      requires that the set of channels that is passed to iio_buffer_register() is
      a subset of the channels assigned to the IIO device as the IIO core will use
      the list of channels that is assigned to the device to lookup a channel by
      scan index in iio_compute_scan_bytes(). If it can not find the channel the
      function will crash. This patch fixes the issue by making sure that the same
      set of channels is assigned to the IIO device and passed to
      iio_buffer_register().
      
      Note that we need to remove the IIO_CHAN_INFO_RAW and IIO_CHAN_INFO_SCALE
      info attributes from the channels since we don't actually want those to be
      registered.
      
      Fixes the following crash:
      	Unable to handle kernel NULL pointer dereference at virtual address 00000016
      	pgd = d2094000
      	[00000016] *pgd=16e39831, *pte=00000000, *ppte=00000000
      	Internal error: Oops: 17 [#1] PREEMPT SMP ARM
      	Modules linked in:
      	CPU: 1 PID: 1695 Comm: bash Not tainted 3.17.0-06329-g29461ee #9686
      	task: d7768040 ti: d5bd4000 task.ti: d5bd4000
      	PC is at iio_compute_scan_bytes+0x38/0xc0
      	LR is at iio_compute_scan_bytes+0x34/0xc0
      	pc : [<c0316de8>]    lr : [<c0316de4>]    psr: 60070013
      	sp : d5bd5ec0  ip : 00000000  fp : 00000000
      	r10: d769f934  r9 : 00000000  r8 : 00000001
      	r7 : 00000000  r6 : c8fc6240  r5 : d769f800  r4 : 00000000
      	r3 : d769f800  r2 : 00000000  r1 : ffffffff  r0 : 00000000
      	Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
      	Control: 18c5387d  Table: 1209404a  DAC: 00000015
      	Process bash (pid: 1695, stack limit = 0xd5bd4240)
      	Stack: (0xd5bd5ec0 to 0xd5bd6000)
      	5ec0: d769f800 d7435640 c8fc6240 d769f984 00000000 c03175a4 d7435690 d7435640
      	5ee0: d769f990 00000002 00000000 d769f800 d5bd4000 00000000 000b43a8 c03177f4
      	5f00: d769f810 0162b8c8 00000002 c8fc7e00 d77f1d08 d77f1da8 c8fc7e00 c01faf1c
      	5f20: 00000002 c010694c c010690c d5bd5f88 00000002 c8fc6840 c8fc684c c0105e08
      	5f40: 00000000 00000000 d20d1580 00000002 000af408 d5bd5f88 c000de84 c00b76d4
      	5f60: d20d1580 000af408 00000002 d20d1580 d20d1580 00000002 000af408 c000de84
      	5f80: 00000000 c00b7a44 00000000 00000000 00000002 b6ebea78 00000002 000af408
      	5fa0: 00000004 c000dd00 b6ebea78 00000002 00000001 000af408 00000002 00000000
      	5fc0: b6ebea78 00000002 000af408 00000004 bee96a4c 000a6094 00000000 000b43a8
      	5fe0: 00000000 bee969cc b6e2eb77 b6e6525c 40070010 00000001 00000000 00000000
      	[<c0316de8>] (iio_compute_scan_bytes) from [<c03175a4>] (__iio_update_buffers+0x248/0x438)
      	[<c03175a4>] (__iio_update_buffers) from [<c03177f4>] (iio_buffer_store_enable+0x60/0x7c)
      	[<c03177f4>] (iio_buffer_store_enable) from [<c01faf1c>] (dev_attr_store+0x18/0x24)
      	[<c01faf1c>] (dev_attr_store) from [<c010694c>] (sysfs_kf_write+0x40/0x4c)
      	[<c010694c>] (sysfs_kf_write) from [<c0105e08>] (kernfs_fop_write+0x110/0x154)
      	[<c0105e08>] (kernfs_fop_write) from [<c00b76d4>] (vfs_write+0xbc/0x170)
      	[<c00b76d4>] (vfs_write) from [<c00b7a44>] (SyS_write+0x40/0x78)
      	[<c00b7a44>] (SyS_write) from [<c000dd00>] (ret_fast_syscall+0x0/0x30)
      
      Fixes: 959d2952 ("staging:iio: make iio_sw_buffer_preenable much more general.")
      Signed-off-by: default avatarLars-Peter Clausen <lars@metafoo.de>
      Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      ef5b2e4d
    • Chris Mason's avatar
      Btrfs: fix kfree on list_head in btrfs_lookup_csums_range error cleanup · 8734fe26
      Chris Mason authored
      commit 6e5aafb2 upstream.
      
      If we hit any errors in btrfs_lookup_csums_range, we'll loop through all
      the csums we allocate and free them.  But the code was using list_entry
      incorrectly, and ended up trying to free the on-stack list_head instead.
      
      This bug came from commit 0678b618
      
      btrfs: Don't BUG_ON kzalloc error in btrfs_lookup_csums_range()
      Signed-off-by: default avatarChris Mason <clm@fb.com>
      Reported-by: default avatarErik Berg <btrfs@slipsprogrammoer.no>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      8734fe26
    • Alexander Stein's avatar
      spi: fsl-dspi: Fix CTAR selection · 0bd11a76
      Alexander Stein authored
      commit 5cc7b047 upstream.
      
      There are only 4 CTAR registers (CTAR0 - CTAR3) so we can only use the
      lower 2 bits of the chip select to select a CTAR register.
      SPI_PUSHR_CTAS used the lower 3 bits which would result in wrong bit values
      if the chip selects 4/5 are used. For those chip selects SPI_CTAR even
      calculated offsets of non-existing registers.
      Signed-off-by: default avatarAlexander Stein <alexander.stein@systec-electronic.com>
      Signed-off-by: default avatarMark Brown <broonie@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      0bd11a76
    • Grant Likely's avatar
      of: Fix overflow bug in string property parsing functions · c26f5a6a
      Grant Likely authored
      commit a87fa1d8 upstream.
      
      The string property read helpers will run off the end of the buffer if
      it is handed a malformed string property. Rework the parsers to make
      sure that doesn't happen. At the same time add new test cases to make
      sure the functions behave themselves.
      
      The original implementations of of_property_read_string_index() and
      of_property_count_strings() both open-coded the same block of parsing
      code, each with it's own subtly different bugs. The fix here merges
      functions into a single helper and makes the original functions static
      inline wrappers around the helper.
      
      One non-bugfix aspect of this patch is the addition of a new wrapper,
      of_property_read_string_array(). The new wrapper is needed by the
      device_properties feature that Rafael is working on and planning to
      merge for v3.19. The implementation is identical both with and without
      the new static inline wrapper, so it just got left in to reduce the
      churn on the header file.
      Signed-off-by: default avatarGrant Likely <grant.likely@linaro.org>
      Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
      Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
      Cc: Rob Herring <robh+dt@kernel.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Darren Hart <darren.hart@intel.com>
      [ kamal: backport to 3.13-stable: context; dropped tests-phandle.dtsi ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c26f5a6a
    • Oliver Neukum's avatar
      xhci: no switching back on non-ULT Haswell · 69c96a2c
      Oliver Neukum authored
      commit b45abacd upstream.
      
      The switch back is limited to ULT even on HP. The contrary
      finding arose by bad luck in BIOS versions for testing.
      This fixes spontaneous resume from S3 on some HP laptops.
      Signed-off-by: default avatarOliver Neukum <oneukum@suse.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      69c96a2c
    • Denis Turischev's avatar
      xhci: Switch only Intel Lynx Point-LP ports to EHCI on shutdown. · 20712469
      Denis Turischev authored
      commit 0a939993 upstream.
      
      Patch "xhci: Switch Intel Lynx Point ports to EHCI on shutdown."
      commit c09ec25d is not fully correct
      
      It switches both Lynx Point and Lynx Point-LP ports to EHCI on shutdown.
      On some Lynx Point machines it causes spurious interrupt,
      which wake the system: bugzilla.kernel.org/show_bug.cgi?id=76291
      
      On Lynx Point-LP on the contrary switching ports to EHCI seems to be
      necessary to fix these spurious interrupts.
      Signed-off-by: default avatarDenis Turischev <denis@compulab.co.il>
      Reported-by: default avatarWulf Richartz <wulf.richartz@gmail.com>
      Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      20712469
    • Alan Stern's avatar
      usb-storage: handle a skipped data phase · d70b19d7
      Alan Stern authored
      commit 93c9bf4d upstream.
      
      Sometimes mass-storage devices using the Bulk-only transport will
      mistakenly skip the data phase of a command.  Rather than sending the
      data expected by the host or sending a zero-length packet, they go
      directly to the status phase and send the CSW.
      
      This causes problems for usb-storage, for obvious reasons.  The driver
      will interpret the CSW as a short data transfer and will wait to
      receive a CSW.  The device won't have anything left to send, so the
      command eventually times out.
      
      The SCSI layer doesn't retry commands after they time out (this is a
      relatively recent change).  Therefore we should do our best to detect
      a skipped data phase and handle it promptly.
      
      This patch adds code to do that.  If usb-storage receives a short
      13-byte data transfer from the device, and if the first four bytes of
      the data match the CSW signature, the driver will set the residue to
      the full transfer length and interpret the data as a CSW.
      
      This fixes Bugzilla #86611.
      Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
      CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
      Tested-by: default avatarPaul Osmialowski <newchief@king.net.pl>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      d70b19d7
    • Hans de Goede's avatar
      usb: Do not allow usb_alloc_streams on unconfigured devices · 357fcce5
      Hans de Goede authored
      commit 90a646c7 upstream.
      
      This commit fixes the following oops:
      
      [10238.622067] scsi host3: uas_eh_bus_reset_handler start
      [10240.766164] usb 3-4: reset SuperSpeed USB device number 3 using xhci_hcd
      [10245.779365] usb 3-4: device descriptor read/8, error -110
      [10245.883331] usb 3-4: reset SuperSpeed USB device number 3 using xhci_hcd
      [10250.897603] usb 3-4: device descriptor read/8, error -110
      [10251.058200] BUG: unable to handle kernel NULL pointer dereference at  0000000000000040
      [10251.058244] IP: [<ffffffff815ac6e1>] xhci_check_streams_endpoint+0x91/0x140
      <snip>
      [10251.059473] Call Trace:
      [10251.059487]  [<ffffffff815aca6c>] xhci_calculate_streams_and_bitmask+0xbc/0x130
      [10251.059520]  [<ffffffff815aeb5f>] xhci_alloc_streams+0x10f/0x5a0
      [10251.059548]  [<ffffffff810a4685>] ? check_preempt_curr+0x75/0xa0
      [10251.059575]  [<ffffffff810a46dc>] ? ttwu_do_wakeup+0x2c/0x100
      [10251.059601]  [<ffffffff810a49e6>] ? ttwu_do_activate.constprop.111+0x66/0x70
      [10251.059635]  [<ffffffff815779ab>] usb_alloc_streams+0xab/0xf0
      [10251.059662]  [<ffffffffc0616b48>] uas_configure_endpoints+0x128/0x150 [uas]
      [10251.059694]  [<ffffffffc0616bac>] uas_post_reset+0x3c/0xb0 [uas]
      [10251.059722]  [<ffffffff815727d9>] usb_reset_device+0x1b9/0x2a0
      [10251.059749]  [<ffffffffc0616f42>] uas_eh_bus_reset_handler+0xb2/0x190 [uas]
      [10251.059781]  [<ffffffff81514293>] scsi_try_bus_reset+0x53/0x110
      [10251.059808]  [<ffffffff815163b7>] scsi_eh_bus_reset+0xf7/0x270
      <snip>
      
      The problem is the following call sequence (simplified):
      
      1) usb_reset_device
      2)  usb_reset_and_verify_device
      2)   hub_port_init
      3)    hub_port_finish_reset
      3)     xhci_discover_or_reset_device
              This frees xhci->devs[slot_id]->eps[ep_index].ring for all eps but 0
      4)    usb_get_device_descriptor
             This fails
      5)   hub_port_init fails
      6)  usb_reset_and_verify_device fails, does not restore device config
      7)  uas_post_reset
      8)   xhci_alloc_streams
            NULL deref on the free-ed ring
      
      This commit fixes this by not allowing usb_alloc_streams to continue if
      the device is not configured.
      
      Note that we do allow usb_free_streams to continue after a (logical)
      disconnect, as it is necessary to explicitly free the streams at the xhci
      controller level.
      Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
      Acked-by: default avatarAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      357fcce5
    • Johan Hovold's avatar
      USB: cdc-acm: add device id for GW Instek AFG-2225 · aefecafb
      Johan Hovold authored
      commit cf84a691 upstream.
      
      Add device-id entry for GW Instek AFG-2225, which has a byte swapped
      bInterfaceSubClass (0x20).
      Reported-by: default avatarKarl Palsson <karlp@tweak.net.au>
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      aefecafb
    • Krzysztof Kozlowski's avatar
      regulator: max77693: Fix use of uninitialized regulator config · 4d0fe845
      Krzysztof Kozlowski authored
      commit ca0c37a0 upstream.
      
      Driver allocated on stack struct regulator_config but didn't initialize
      it fully. Few fields (driver_data, ena_gpio) were left untouched. This
      lead to using random ena_gpio values as GPIOs for max77693 regulators.
      
      On occasion these values could match real GPIO numbers leading to
      interfering with other drivers and to unsuccessful enable/disable of
      regulator.
      Signed-off-by: default avatarKrzysztof Kozlowski <k.kozlowski@samsung.com>
      Fixes: 80b022e2 ("regulator: max77693: Add max77693 regualtor driver.")
      Signed-off-by: default avatarMark Brown <broonie@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      4d0fe845
    • Johan Hovold's avatar
      USB: opticon: fix non-atomic allocation in write path · 5fad1d64
      Johan Hovold authored
      commit e681286d upstream.
      
      Write may be called from interrupt context so make sure to use
      GFP_ATOMIC for all allocations in write.
      
      Fixes: 0d930e51 ("USB: opticon: Add Opticon OPN2001 write support")
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      5fad1d64
    • Johan Hovold's avatar
      USB: kobil_sct: fix non-atomic allocation in write path · c594b087
      Johan Hovold authored
      commit 19125283 upstream.
      
      Write may be called from interrupt context so make sure to use
      GFP_ATOMIC for all allocations in write.
      
      Fixes: 1da177e4 ("Linux-2.6.12-rc2")
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c594b087
    • Anton Blanchard's avatar
      powerpc: do_notify_resume can be called with bad thread_info flags argument · 38c96f03
      Anton Blanchard authored
      commit 808be314 upstream.
      
      Back in 7230c564 ("powerpc: Rework lazy-interrupt handling") we
      added a call out to restore_interrupts() (written in c) before calling
      do_notify_resume:
      
              bl      restore_interrupts
              addi    r3,r1,STACK_FRAME_OVERHEAD
              bl      do_notify_resume
      
      Unfortunately do_notify_resume takes two arguments, the second one
      being the thread_info flags:
      
      void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags)
      
      We do populate r4 (the second argument) earlier, but
      restore_interrupts() is free to muck it up all it wants. My guess is
      the gcc compiler gods shone down on us and its register allocator
      never used r4. Sometimes, rarely, luck is on our side.
      
      LLVM on the other hand did trample r4.
      Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      [ kamal: backport to 3.13-stable: context ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      38c96f03
    • Ulrich Eckhardt's avatar
      [media] ds3000: fix LNB supply voltage on Tevii S480 on initialization · 683d6700
      Ulrich Eckhardt authored
      commit 8c5bcded upstream.
      
      The Tevii S480 outputs 18V on startup for the LNB supply voltage and does not
      automatically power down. This blocks other receivers connected
      to a satellite channel router (EN50494), since the receivers can not send the
      required DiSEqC sequences when the Tevii card is connected to a the same SCR.
      
      This patch switches off the LNB supply voltage on initialization of the frontend.
      
      [mchehab@osg.samsung.com: add a comment about why we're explicitly
       turning off voltage at device init]
      Signed-off-by: default avatarUlrich Eckhardt <uli@uli-eckhardt.de>
      Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@osg.samsung.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      683d6700
    • Jan Kara's avatar
      rbd: Fix error recovery in rbd_obj_read_sync() · 02485a1c
      Jan Kara authored
      commit a8d42056 upstream.
      
      When we fail to allocate page vector in rbd_obj_read_sync() we just
      basically ignore the problem and continue which will result in an oops
      later. Fix the problem by returning proper error.
      
      CC: Yehuda Sadeh <yehuda@inktank.com>
      CC: Sage Weil <sage@inktank.com>
      CC: ceph-devel@vger.kernel.org
      Coverity-id: 1226882
      Signed-off-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarIlya Dryomov <idryomov@redhat.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      02485a1c
    • Hans de Goede's avatar
      acer-wmi: Add acpi_backlight=video quirk for the Acer KAV80 · 22f13c00
      Hans de Goede authored
      commit 183fd8fc upstream.
      
      The acpi-video backlight interface on the Acer KAV80 is broken, and worse
      it causes the entire machine to slow down significantly after a suspend/resume.
      
      Blacklist it, and use the acer-wmi backlight interface instead. Note that
      the KAV80 is somewhat unique in that it is the only Acer model where we
      fall back to acer-wmi after blacklisting, rather then using the native
      (e.g. intel) backlight driver. This is done because there is no native
      backlight interface on this model.
      
      BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1128309Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
      Signed-off-by: default avatarDarren Hart <dvhart@linux.intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      22f13c00
    • Hans de Goede's avatar
      acer-wmi: Add Aspire 5741 to video_vendor_dmi_table · 6e9a4622
      Hans de Goede authored
      commit 9404cd95 upstream.
      
      The Aspire 5741 has broken acpi-video backlight control, so add it to the
      quirk table.
      
      References: https://bugzilla.redhat.com/show_bug.cgi?id=1012674Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
      Reviewed-by: default avatarLee, Chun-Yi <jlee@suse.com>
      Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      6e9a4622
    • Hans de Goede's avatar
      samsung-laptop: Add broken-acpi-video quirk for NC210/NC110 · e4570e7c
      Hans de Goede authored
      commit 5a1426c9 upstream.
      
      The acpi-video backlight interface on the NC210 does not work, blacklist it
      and use the samsung-laptop interface instead.
      
      BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=861573Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
      Signed-off-by: default avatarDarren Hart <dvhart@linux.intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      e4570e7c
    • Robert Jarzmik's avatar
      ARM: pxa: fix hang on startup with DEBUG_LL · 6bff48fd
      Robert Jarzmik authored
      commit cde7fc87 upstream.
      
      The commit 2111667b ("ARM: pxa: call debug_ll_io_init for
      earlyprintk") triggers in the current kernel the attached backtrace on
      PXA/tosa early in the boot time when DEBUG_LL is enabled.
      
      It is due to overlap between uart virtual memory defined in
      DEBUG_UART_VIRT and mapped by debug_ll_io_init() and peripheral bus
      mapped by pxa_map_io at the same address, 0xf2100000.
      
      As hinted by Arnd, map early virtual memory for low level debug on
      address 0xf6200000, even if that means 2 virtual mappings will give
      access to the pxa internal UARTs (FFUART, BTUART, STUART, ...).
      
      ------------[ cut here ]------------
      kernel BUG at /home/lumag/linux/mm/vmalloc.c:1143!
      Internal error: Oops - BUG: 0 [#1] PREEMPT ARM
      Modules linked in:
      CPU: 0 PID: 0 Comm: swapper Not tainted 3.17.0-00032-g8e0d202-dirty #23
      task: c062a5a8 ti: c0620000 task.ti: c0620000
      PC is at vm_area_add_early+0x54/0x84
      LR is at add_static_vm_early+0xc/0x60
      pc : [<c03e1100>]    lr : [<c03d9ef4>]    psr: 800001d3
      sp : c0621f04  ip : c03efa74  fp : c03edf84
      r10: c0637e98  r9 : 40000001  r8 : c03da57c
      r7 : c3ffcfb0  r6 : 00000000  r5 : c3ffcfb0  r4 : 02000000
      r3 : c3ffcfd8  r2 : f2100000  r1 : f4000000  r0 : c3ffcfb0
      Flags: Nzcv  IRQs off  FIQs off  Mode SVC_32  ISA ARM  Segment kernel
      Control: 00007977  Table: a0004000  DAC: 00000017
      Process swapper (pid: 0, stack limit = 0xc06201c8)
      Stack: (0xc0621f04 to 0xc0622000)
      1f00:          c3ffcfd8 40000001 c3ffcfd8 c03ee08c c03da570 c03db90c c0637d24
      1f20: 00000000 c03ec7cc c066e654 a0700000 000a0700 c03db914 c03db90c c03daf84
      1f40: 00000000 000a0000 c0000000 c03ec7cc 000a0700 c0700000 ffff1000 000a3fff
      1f60: 00001000 00000007 00000000 c03ec7cc c0008000 c03ed748 c0621fd4 c03d5d18
      1f80: 69052d00 a03ec48c 00000000 c03d8ad0 0000006c 00007977 c036c6e8 00000001
      1fa0: c0621fd4 c03ed744 c0628000 a0004000 69052d00 a03ec48c 00000000 c03d68d4
      1fc0: 00000000 00000000 00000000 00000000 00000000 c03ed748 c0649894 c062801c
      1fe0: c03ed744 c062b2f0 a0004000 69052d00 a03ec48c a0008040 00000000 00000000
      [<c03e1100>] (vm_area_add_early) from [<c03d9ef4>] (add_static_vm_early+0xc/0x60)
      [<c03d9ef4>] (add_static_vm_early) from [<c03da570>] (iotable_init.part.6+0xa8/0xb4)
      [<c03da570>] (iotable_init.part.6) from [<c03db914>] (pxa25x_map_io+0x8/0x24)
      [<c03db914>] (pxa25x_map_io) from [<c03daf84>] (paging_init+0x744/0x8d8)
      [<c03daf84>] (paging_init) from [<c03d8ad0>] (setup_arch+0x354/0x608)
      [<c03d8ad0>] (setup_arch) from [<c03d68d4>] (start_kernel+0xa8/0x3dc)
      [<c03d68d4>] (start_kernel) from [<a0008040>] (0xa0008040)
      Code: e5904008 e0811004 e1520001 2a000005 (e7f001f2)
      ---[ end trace f24b6c88ae00fa9a ]---
      Kernel panic - not syncing: Attempted to kill the idle task!
      ---[ end Kernel panic - not syncing: Attempted to kill the idle task!
      Reported-by: default avatarDmitry Eremin-Solenikov <dbaryshkov@gmail.com>
      Signed-off-by: default avatarRobert Jarzmik <robert.jarzmik@free.fr>
      Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      6bff48fd
  3. 24 Nov, 2014 4 commits
    • Kyle McMartin's avatar
      arm64: __clear_user: handle exceptions on strb · 1d7eacab
      Kyle McMartin authored
      commit 97fc1543 upstream.
      
      ARM64 currently doesn't fix up faults on the single-byte (strb) case of
      __clear_user... which means that we can cause a nasty kernel panic as an
      ordinary user with any multiple PAGE_SIZE+1 read from /dev/zero.
      i.e.: dd if=/dev/zero of=foo ibs=1 count=1 (or ibs=65537, etc.)
      
      This is a pretty obscure bug in the general case since we'll only
      __do_kernel_fault (since there's no extable entry for pc) if the
      mmap_sem is contended. However, with CONFIG_DEBUG_VM enabled, we'll
      always fault.
      
      if (!down_read_trylock(&mm->mmap_sem)) {
      	if (!user_mode(regs) && !search_exception_tables(regs->pc))
      		goto no_context;
      retry:
      	down_read(&mm->mmap_sem);
      } else {
      	/*
      	 * The above down_read_trylock() might have succeeded in
      	 * which
      	 * case, we'll have missed the might_sleep() from
      	 * down_read().
      	 */
      	might_sleep();
      	if (!user_mode(regs) && !search_exception_tables(regs->pc))
      		goto no_context;
      }
      
      Fix that by adding an extable entry for the strb instruction, since it
      touches user memory, similar to the other stores in __clear_user.
      Signed-off-by: default avatarKyle McMartin <kyle@redhat.com>
      Reported-by: default avatarMiloš Prchlík <mprchlik@redhat.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      Reference: CVE-2014-7843
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      1d7eacab
    • Dan Carpenter's avatar
      [media] ttusb-dec: buffer overflow in ioctl · 7d52fe2f
      Dan Carpenter authored
      commit f2e323ec upstream.
      
      We need to add a limit check here so we don't overflow the buffer.
      Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@osg.samsung.com>
      Reference: CVE-2014-8884
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      7d52fe2f
    • Nadav Amit's avatar
      KVM: x86: Don't report guest userspace emulation error to userspace · bdf5160c
      Nadav Amit authored
      commit a2b9e6c1 upstream.
      
      Commit fc3a9157 ("KVM: X86: Don't report L2 emulation failures to
      user-space") disabled the reporting of L2 (nested guest) emulation failures to
      userspace due to race-condition between a vmexit and the instruction emulator.
      The same rational applies also to userspace applications that are permitted by
      the guest OS to access MMIO area or perform PIO.
      
      This patch extends the current behavior - of injecting a #UD instead of
      reporting it to userspace - also for guest userspace code.
      Signed-off-by: default avatarNadav Amit <namit@cs.technion.ac.il>
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      Reference: CVE-2014-7842
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      bdf5160c
    • Daniel Borkmann's avatar
      net: sctp: fix NULL pointer dereference in af->from_addr_param on malformed packet · cef3496d
      Daniel Borkmann authored
      commit e40607cb upstream.
      
      An SCTP server doing ASCONF will panic on malformed INIT ping-of-death
      in the form of:
      
        ------------ INIT[PARAM: SET_PRIMARY_IP] ------------>
      
      While the INIT chunk parameter verification dissects through many things
      in order to detect malformed input, it misses to actually check parameters
      inside of parameters. E.g. RFC5061, section 4.2.4 proposes a 'set primary
      IP address' parameter in ASCONF, which has as a subparameter an address
      parameter.
      
      So an attacker may send a parameter type other than SCTP_PARAM_IPV4_ADDRESS
      or SCTP_PARAM_IPV6_ADDRESS, param_type2af() will subsequently return 0
      and thus sctp_get_af_specific() returns NULL, too, which we then happily
      dereference unconditionally through af->from_addr_param().
      
      The trace for the log:
      
      BUG: unable to handle kernel NULL pointer dereference at 0000000000000078
      IP: [<ffffffffa01e9c62>] sctp_process_init+0x492/0x990 [sctp]
      PGD 0
      Oops: 0000 [#1] SMP
      [...]
      Pid: 0, comm: swapper Not tainted 2.6.32-504.el6.x86_64 #1 Bochs Bochs
      RIP: 0010:[<ffffffffa01e9c62>]  [<ffffffffa01e9c62>] sctp_process_init+0x492/0x990 [sctp]
      [...]
      Call Trace:
       <IRQ>
       [<ffffffffa01f2add>] ? sctp_bind_addr_copy+0x5d/0xe0 [sctp]
       [<ffffffffa01e1fcb>] sctp_sf_do_5_1B_init+0x21b/0x340 [sctp]
       [<ffffffffa01e3751>] sctp_do_sm+0x71/0x1210 [sctp]
       [<ffffffffa01e5c09>] ? sctp_endpoint_lookup_assoc+0xc9/0xf0 [sctp]
       [<ffffffffa01e61f6>] sctp_endpoint_bh_rcv+0x116/0x230 [sctp]
       [<ffffffffa01ee986>] sctp_inq_push+0x56/0x80 [sctp]
       [<ffffffffa01fcc42>] sctp_rcv+0x982/0xa10 [sctp]
       [<ffffffffa01d5123>] ? ipt_local_in_hook+0x23/0x28 [iptable_filter]
       [<ffffffff8148bdc9>] ? nf_iterate+0x69/0xb0
       [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0
       [<ffffffff8148bf86>] ? nf_hook_slow+0x76/0x120
       [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0
      [...]
      
      A minimal way to address this is to check for NULL as we do on all
      other such occasions where we know sctp_get_af_specific() could
      possibly return with NULL.
      
      Fixes: d6de3097 ("[SCTP]: Add the handling of "Set Primary IP Address" parameter to INIT")
      Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
      Cc: Vlad Yasevich <vyasevich@gmail.com>
      Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Reference: CVE-2014-7841
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      cef3496d
  4. 21 Nov, 2014 6 commits
    • Pranith Kumar's avatar
      rcu: Use rcu_gp_kthread_wake() to wake up grace period kthreads · 1659354a
      Pranith Kumar authored
      commit 2aa792e6 upstream.
      
      The rcu_gp_kthread_wake() function checks for three conditions before
      waking up grace period kthreads:
      
      *  Is the thread we are trying to wake up the current thread?
      *  Are the gp_flags zero? (all threads wait on non-zero gp_flags condition)
      *  Is there no thread created for this flavour, hence nothing to wake up?
      
      If any one of these condition is true, we do not call wake_up().
      It was found that there are quite a few avoidable wake ups both during
      idle time and under stress induced by rcutorture.
      
      Idle:
      
      Total:66000, unnecessary:66000, case1:61827, case2:66000, case3:0
      Total:68000, unnecessary:68000, case1:63696, case2:68000, case3:0
      
      rcutorture:
      
      Total:254000, unnecessary:254000, case1:199913, case2:254000, case3:0
      Total:256000, unnecessary:256000, case1:201784, case2:256000, case3:0
      
      Here case{1-3} are the cases listed above. We can avoid these wake
      ups by using rcu_gp_kthread_wake() to conditionally wake up the grace
      period kthreads.
      
      There is a comment about an implied barrier supplied by the wake_up()
      logic.  This barrier is necessary for the awakened thread to see the
      updated ->gp_flags.  This flag is always being updated with the root node
      lock held. Also, the awakened thread tries to acquire the root node lock
      before reading ->gp_flags because of which there is proper ordering.
      
      Hence this commit tries to avoid calling wake_up() whenever we can by
      using rcu_gp_kthread_wake() function.
      Signed-off-by: default avatarPranith Kumar <bobby.prani@gmail.com>
      CC: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      1659354a
    • Paul E. McKenney's avatar
      rcu: Make callers awaken grace-period kthread · 0facc006
      Paul E. McKenney authored
      commit 48a7639c upstream.
      
      The rcu_start_gp_advanced() function currently uses irq_work_queue()
      to defer wakeups of the RCU grace-period kthread.  This deferring
      is necessary to avoid RCU-scheduler deadlocks involving the rcu_node
      structure's lock, meaning that RCU cannot call any of the scheduler's
      wake-up functions while holding one of these locks.
      
      Unfortunately, the second and subsequent calls to irq_work_queue() are
      ignored, and the first call will be ignored (aside from queuing the work
      item) if the scheduler-clock tick is turned off.  This is OK for many
      uses, especially those where irq_work_queue() is called from an interrupt
      or softirq handler, because in those cases the scheduler-clock-tick state
      will be re-evaluated, which will turn the scheduler-clock tick back on.
      On the next tick, any deferred work will then be processed.
      
      However, this strategy does not always work for RCU, which can be invoked
      at process level from idle CPUs.  In this case, the tick might never
      be turned back on, indefinitely defering a grace-period start request.
      Note that the RCU CPU stall detector cannot see this condition, because
      there is no RCU grace period in progress.  Therefore, we can (and do!)
      see long tens-of-seconds stalls in grace-period handling.  In theory,
      we could see a full grace-period hang, but rcutorture testing to date
      has seen only the tens-of-seconds stalls.  Event tracing demonstrates
      that irq_work_queue() is being called repeatedly to no effect during
      these stalls: The "newreq" event appears repeatedly from a task that is
      not one of the grace-period kthreads.
      
      In theory, irq_work_queue() might be fixed to avoid this sort of issue,
      but RCU's requirements are unusual and it is quite straightforward to pass
      wake-up responsibility up through RCU's call chain, so that the wakeup
      happens when the offending locks are released.
      
      This commit therefore makes this change.  The rcu_start_gp_advanced(),
      rcu_start_future_gp(), rcu_accelerate_cbs(), rcu_advance_cbs(),
      __note_gp_changes(), and rcu_start_gp() functions now return a boolean
      which indicates when a wake-up is needed.  A new rcu_gp_kthread_wake()
      does the wakeup when it is necessary and safe to do so: No self-wakes,
      no wake-ups if the ->gp_flags field indicates there is no need (as in
      someone else did the wake-up before we got around to it), and no wake-ups
      before the grace-period kthread has been created.
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Reviewed-by: default avatarJosh Triplett <josh@joshtriplett.org>
      [ Pranith: backport to 3.13-stable: just rcu_gp_kthread_wake(),
        prereq for 2aa792e6 "rcu: Use rcu_gp_kthread_wake() to wake up grace
        period kthreads" ]
      Signed-off-by: default avatarPranith Kumar <bobby.prani@gmail.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      0facc006
    • Mengdong Lin's avatar
      ALSA: hda - restore BCLK M/N value as per CDCLK for HSW/BDW display HDA controller · 8b2cea0d
      Mengdong Lin authored
      commit e4d9e513 upstream.
      
      For HSW/BDW display HD-A controller, hda_set_bclk() is defined to set BCLK
      by programming the M/N values as per the core display clock (CDCLK) queried from
      i915 display driver.
      
      And the audio driver will also set BCLK in azx_first_init() since the display
      driver can turn off the shared power in boot phase if only eDP is connected
      and M/N values will be lost and must be reprogrammed.
      Signed-off-by: default avatarMengdong Lin <mengdong.lin@intel.com>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      [ 3.13-stable: takashi's backport for 3.{12,13} ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      8b2cea0d
    • Jani Nikula's avatar
      drm/i915: provide interface for audio driver to query cdclk · 5a767321
      Jani Nikula authored
      commit c149dcb5 upstream.
      
      For Haswell and Broadwell, if the display power well has been disabled,
      the display audio controller divider values EM4 M VALUE and EM5 N VALUE
      will have been lost. The CDCLK frequency is required for reprogramming them
      to generate 24MHz HD-A link BCLK. So provide a private interface for the
      audio driver to query CDCLK.
      
      This is a stopgap solution until a more generic interface between audio
      and display drivers has been implemented.
      Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
      Reviewed-by: default avatarDamien Lespiau <damien.lespiau@intel.com>
      Signed-off-by: default avatarMengdong Lin <mengdong.lin@intel.com>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      5a767321
    • Takashi Iwai's avatar
      drm/i915, HD-audio: Don't continue probing when nomodeset is given · 99285abe
      Takashi Iwai authored
      commit 74b0c2d7 upstream.
      
      When a machine is booted with nomodeset option, i915 driver skips the
      whole initialization.  Meanwhile, HD-audio tries to bind wth i915 just
      by request_symbol() without knowing that the initialization was
      skipped, and eventually it hits WARN_ON() in i915_request_power_well()
      and i915_release_power_well() wrongly but still continues probing,
      even though it doesn't work at all.
      
      In this patch, both functions are changed to return an error in case
      of uninitialized state instead of WARN_ON(), so that HD-audio driver
      can give up HDMI controller initialization at the right time.
      Acked-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      99285abe
    • Kamal Mostafa's avatar
      Revert "ALSA: hda - restore BCLK M/N values when resuming HSW/BDW display controller" · f5c96f4a
      Kamal Mostafa authored
      This reverts commit 72f0c0f4.
      
      [ kamal: 3.13-stable: to be replaced by Takashi backport ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      f5c96f4a