Pull input layer fix from Dmitry Torokhov:
 "A small fixup to gpio_keys_polled driver"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: gpio_keys_polled - request GPIO pin as input.

Pull drm fixes from Dave Airlie:
 "A bunch of i915 fixes, one revert a VBT fix that was a bit premature,
  and some braswell feature removal that the hw actually didn't support.

  One radeon race fix at boot, and one hlcdc build fix, one fix from
  Russell that fixes build as well with new audio features.

  This is hopefully all I have until -next"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon: fix hotplug race at startup
  drm/edid: add function to help find SADs
  drm/i915: Avoid TP3 on CHV
  drm/i915: remove HBR2 from chv supported list
  Revert "drm/i915: Add eDP intermediate frequencies for CHV"
  Revert "drm/i915: Allow parsing of variable size child device entries from VBT"
  drm/atmel-hlcdc: Compile suspend/resume for PM_SLEEP only
  drm/i915: Flag the execlists context object as dirty after every use

We apparantly get a hotplug irq before we've initialised
modesetting,

[drm] Loading R100 Microcode
BUG: unable to handle kernel NULL pointer dereference at   (null)
IP: [<c125f56f>] __mutex_lock_slowpath+0x23/0x91
*pde = 00000000
Oops: 0002 [#1]
Modules linked in: radeon(+) drm_kms_helper ttm drm i2c_algo_bit backlight pcspkr psmouse evdev sr_mod input_leds led_class cdrom sg parport_pc parport floppy intel_agp intel_gtt lpc_ich acpi_cpufreq processor button mfd_core agpgart uhci_hcd ehci_hcd rng_core snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm usbcore usb_common i2c_i801 i2c_core snd_timer snd soundcore thermal_sys
CPU: 0 PID: 15 Comm: kworker/0:1 Not tainted 4.2.0-rc7-00015-gbf674028 #111
Hardware name: MicroLink                               /D850MV                         , BIOS MV85010A.86A.0067.P24.0304081124 04/08/2003
Workqueue: events radeon_hotplug_work_func [radeon]
task: f6ca5900 ti: f6d3e000 task.ti: f6d3e000
EIP: 0060:[<c125f56f>] EFLAGS: 00010282 CPU: 0
EIP is at __mutex_lock_slowpath+0x23/0x91
EAX: 00000000 EBX: f5e900fc ECX: 00000000 EDX: fffffffe
ESI: f6ca5900 EDI: f5e90100 EBP: f5e90000 ESP: f6d3ff0c
 DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
CR0: 8005003b CR2: 00000000 CR3: 36f61000 CR4: 000006d0
Stack:
 f5e90100 00000000 c103c4c1 f6d2a5a0 f5e900fc f6df394c c125f162 f8b0faca
 f6d2a5a0 c138ca00 f6df394c f7395600 c1034741 00d40000 00000000 f6d2a5a0
 c138ca00 f6d2a5b8 c138ca10 c1034b58 00000001 f6d40000 f6ca5900 f6d0c940
Call Trace:
 [<c103c4c1>] ? dequeue_task_fair+0xa4/0xb7
 [<c125f162>] ? mutex_lock+0x9/0xa
 [<f8b0faca>] ? radeon_hotplug_work_func+0x17/0x57 [radeon]
 [<c1034741>] ? process_one_work+0xfc/0x194
 [<c1034b58>] ? worker_thread+0x18d/0x218
 [<c10349cb>] ? rescuer_thread+0x1d5/0x1d5
 [<c103742a>] ? kthread+0x7b/0x80
 [<c12601c0>] ? ret_from_kernel_thread+0x20/0x30
 [<c10373af>] ? init_completion+0x18/0x18
Code: 42 08 e8 8e a6 dd ff c3 57 56 53 83 ec 0c 8b 35 48 f7 37 c1 8b 10 4a 74 1a 89 c3 8d 78 04 8b 40 08 89 63
Reported-and-Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Dave Airlie <airlied@redhat.com>

Revert of a VBT parsing commit that should've been queued for drm-next,
not v4.2. The revert unbreaks Braswell among other things.

Also on Braswell removal of DP HBR2/TP3 and intermediate eDP frequency
support. The code was optimistically added based on incorrect
documentation; the platform does not support them. These are cc: stable.

Finally a gpu state fix from Chris, also cc: stable.

* tag 'drm-intel-fixes-2015-08-20' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Avoid TP3 on CHV
  drm/i915: remove HBR2 from chv supported list
  Revert "drm/i915: Add eDP intermediate frequencies for CHV"
  Revert "drm/i915: Allow parsing of variable size child device entries from VBT"
  drm/i915: Flag the execlists context object as dirty after every use

Pull power management and ACPI fixes from Rafael Wysocki:
 "These fix a recent regression in the ACPI backlight code and a memory
  leak in the Exynos cpufreq driver.

  Specifics:

   - Fix a recently introduced issue in the ACPI backlight code which
     causes lockdep to complain about a circular lock dependency during
     initialization (Hans de Goede).

   - Fix a possible memory during initialization in the Exynos cpufreq
     driver (Shailendra Verma)"

* tag 'pm+acpi-4.2-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: exynos: Fix for memory leak in case SoC name does not match
  ACPI / video: Fix circular lock dependency issue in the video-detect code

* acpi-video:
  ACPI / video: Fix circular lock dependency issue in the video-detect code

* cpufreq-fixes:
  cpufreq: exynos: Fix for memory leak in case SoC name does not match

Pull networking fixes from David Miller:

 1) Out of bounds array access in 802.11 minstrel code, from Adrien
    Schildknecht.

 2) Don't use skb_get() in IGMP/MLD code paths, as this makes
    pskb_may_pull() BUG.  From Linus Luessing.

 3) Fix off by one in ipv4 route dumping code, from Andy Whitcroft.

 4) Fix deadlock in reqsk_queue_unlink(), from Eric Dumazet.

 5) Fix ppp device deregistration wrt.  netns deletion, from Guillaume
    Nault.

 6) Fix deadlock when creating per-cpu ipv6 routes, from Martin KaFai
    Lau.

 7) Fix memory leak in batman-adv code, from Sven Eckelmann.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  batman-adv: Fix memory leak on tt add with invalid vlan
  net: phy: fix semicolon.cocci warnings
  net: qmi_wwan: add HP lt4111 LTE/EV-DO/HSPA+ Gobi 4G Module
  be2net: avoid vxlan offloading on multichannel configs
  ipv6: Fix a potential deadlock when creating pcpu rt
  ipv6: Add rt6_make_pcpu_route()
  ipv6: Remove un-used argument from ip6_dst_alloc()
  net: phy: workaround for buggy cable detection by LAN8700 after cable plugging
  net: ethernet: micrel: fix an error code
  ppp: fix device unregistration upon netns deletion
  net: phy: fix PHY_RUNNING in phy_state_machine
  Revert "net: limit tcp/udp rmem/wmem to SOCK_{RCV,SND}BUF_MIN"
  inet: fix potential deadlock in reqsk_queue_unlink()
  gianfar: Restore link state settings after MAC reset
  ipv4: off-by-one in continuation handling in /proc/net/route
  net: fix wrong skb_get() usage / crash in IGMP/MLD parsing code
  mac80211: fix invalid read in minstrel_sort_best_tp_rates()

Pull xen build fix from David Vrabel:
 "Fix i386 build with an (uncommon) configuration"

* tag 'for-linus-4.2-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: make CONFIG_XEN depend on CONFIG_X86_LOCAL_APIC

Pull sound fixes from Takashi Iwai:
 "Here are a small collecton of sound fix patches.

  The most significant one is the disablement of newly introduced
  topology API.  Its ABI couldn't be stabilized enough, so we decided to
  delay for 4.3 in the end.  Other than that, all oneliner fixes: a
  USB-audio runtime PM fix and a couple of HD-audio quirks"

* tag 'sound-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Add dock support for Thinkpad W541 (17aa:2211)
  ALSA: usb-audio: Fix runtime PM unbalance
  ASoC: topology: Disable use from userspace
  ASoC: topology: Add Kconfig option for topology
  ALSA: hda - Fix the white noise on Dell laptop

GPIOF_IN flag was lost in:
Commit 633a21d8("input: gpio_keys_polled: Add support for GPIO
descriptors").

Without this flag, legacy code path (for non-descriptor GPIO declarations)
would configure GPIO as output (0 meaning GPIOF_DIR_OUT | GPIOF_INIT_LOW).

Cc: stable@vger.kernel.org
Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Pull SCSI target fixes from Nicholas Bellinger:
 "This contains a v4.2-rc specific RCU module unload regression bug-fix,
  a long-standing iscsi-target bug-fix for duplicate target_xfer_tags
  during NOP processing from Alexei, and two more small REPORT_LUNs
  emulation related patches to make Solaris FC host LUN scanning happy
  from Roland.

  There is also one patch not included that allows target-core to limit
  the number of fabric driver SGLs per I/O request using residuals, that
  is currently required as a work-around for FC hosts which don't honor
  EVPD block-limits settings.  At this point, it will most likely become
  for-next material"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target: Fix handling of small allocation lengths in REPORT LUNS
  target: REPORT LUNS should return LUN 0 even for dynamic ACLs
  target/iscsi: Fix double free of a TUR followed by a solicited NOPOUT
  target: Perform RCU callback barrier before backend/fabric unload

Pull thermal fixes from Eduardo Valentin:
 "Last minute fixes on the thermal-soc tree.  There is a fix of a long
  lasting bug in cpu cooling device, thanks for RMK for being pushing
  this"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  thermal/cpu_cooling: update policy limits if clipped_freq < policy->max
  thermal/cpu_cooling: rename max_freq as clipped_freq in notifier
  thermal/cpu_cooling: rename cpufreq_val as clipped_freq
  thermal/cpu_cooling: convert 'switch' block to 'if' block in notifier
  thermal/cpu_cooling: quit early after updating policy
  thermal/cpu_cooling: No need to initialize max_freq to 0
  thermal: cpu_cooling: fix lockdep problems in cpu_cooling
  thermal: power_allocator: do not use devm* interfaces

Since commit feb44f1f (x86/xen:
Provide a "Xen PV" APIC driver to support >255 VCPUs) Xen guests need
a full APIC driver and thus should depend on X86_LOCAL_APIC.

This fixes an i386 build failure with !SMP && !CONFIG_X86_UP_APIC by
disabling Xen support in this configuration.

Users needing Xen support in a non-SMP i386 kernel will need to enable
CONFIG_X86_UP_APIC.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: <stable@vger.kernel.org>

Add a function to find the start of the SADs in the ELD.  This
complements the helper to retrieve the SAD count.

[airlied: this fixes a build problem with the alsa eld helper
which required this].
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>

single atmel hlcdc fix.

* 'drm-atmel-hlcdc-fixes' of https://github.com/bbrezillon/linux-at91:
  drm/atmel-hlcdc: Compile suspend/resume for PM_SLEEP only

Merge tag 'asoc-v4.2-disable-topology' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Disable topology support for v4.2

The topology code merged in the v4.2 merge window introduced a new ABI
which was believed to be suitable for use but subsequently additional
work by the developers of this feature have revealed some problems that
need to be addressed.  In order to allow this to be done without having
to support the initial ABI add Kconfig to disable the build and also add
some #error statements to the UAPI header so users can't use them.

Tested with W541 and Ultra Dock 170w
Signed-off-by: Rick Sherman <rick@shermdog.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

The fix for deadlock in PM in commit [1ee23fe0: ALSA: usb-audio:
Fix deadlocks at resuming] introduced a new check of in_pm flag.
However, the brainless patch author evaluated it in a wrong way
(logical AND instead of logical OR), thus usb_autopm_get_interface()
is wrongly called at probing, leading to unbalance of runtime PM
refcount.

This patch fixes it by correcting the logic.
Reported-by: Hans Yang <hansy@nvidia.com>
Fixes: 1ee23fe0 ('ALSA: usb-audio: Fix deadlocks at resuming')
Cc: <stable@vger.kernel.org> [v3.15+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>

This patch removes TP3 support on CHV since there is no support
for HBR2 on this platform.

v2: rename the function to indicate it checks source rates (Jani)
v3: update comment to indicate TP3 dependency on HBR2 supported
    hardware (Jani)

Cc: stable@vger.kernel.org # v4.1+
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
[Jani: fixed a couple of checkpatch warnings.]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

This patch removes 5.4Gbps from supported link rate for CHV since
it is not supported in it.

v2: change the ordering for better readability (Ville)

Cc: stable@vger.kernel.org # v4.1+
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

This reverts
commit fe51bfb9.
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date:   Thu Mar 12 17:10:38 2015 +0200

CHV does not support intermediate frequencies so reverting the
patch that added it in the first place

Cc: stable@vger.kernel.org # v4.1+
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

This reverts

commit 047fe6e6
Author: David Weinehall <david.weinehall@linux.intel.com>
Date:   Tue Aug 4 16:55:52 2015 +0300

    drm/i915: Allow parsing of variable size child device entries from VBT

That commit is not valid for v4.2, however it will be valid for v4.3. It
was simply queued too early.

The referenced regressing commit is just fine until the size of struct
common_child_dev_config changes, and that won't happen until
v4.3. Indeed, the expected size checks here rely on the increased size
of the struct, breaking new platforms.

Fixes: 047fe6e6 ("drm/i915: Allow parsing of variable size child device entries from VBT")
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Weinehall <david.weinehall@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

REPORT LUNS should not fail just because the allocation length is less
than 16.  The relevant section of SPC-4 is:

  4.2.5.6 Allocation length

  The ALLOCATION LENGTH field specifies the maximum number of bytes or
  blocks that an application client has allocated in the Data-In
  Buffer. The ALLOCATION LENGTH field specifies bytes unless a
  different requirement is stated in the command definition.

  An allocation length of zero specifies that no data shall be
  transferred. This condition shall not be considered an error.

So we should just truncate our response rather than return an error.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Spencer Baugh <sbaugh@catern.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

The object tt_local is allocated with kmalloc and not initialized when the
function batadv_tt_local_add checks for the vlan. But this function can
only cleanup the object when the (not yet initialized) reference counter of
the object is 1. This is unlikely and thus the object would leak when the
vlan could not be found.

Instead the uninitialized object tt_local has to be freed manually and the
pointer has to set to NULL to avoid calling the function which would try to
decrement the reference counter of the not existing object.

CID: 1316518
Fixes: 354136bc ("batman-adv: fix kernel crash due to missing NULL checks")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull dmaengine fix from Vinod Koul:
 "We recently found issue with dma_request_slave_channel() API causing
  privatecnt value to go bad.  This is fixed by balancing the privatecnt"

* tag 'dmaengine-fix-4.2-rc8' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: fix balance of privatecnt inc/dec operations

Since the topology API is still in sufficient flux for changes to be
identified disable the use of the userspace ABI by adding #error
statements to the code, ensuring that nobody relies on the headers as
currently defined.  It is expected that this change will be reverted for
v4.3.
Signed-off-by: Mark Brown <broonie@kernel.org>

Pull drm fixes from Dave Airlie:
 "These came in late last week, I wanted to look over the mst one before
  forwarding, but it seems good.

  Just three i915 and one MST fix"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: Commit planes on each crtc separately.
  drm/i915: calculate primary visibility changes instead of calling from set_config
  drm/i915: Only dither on 6bpc panels
  drm/dp/mst: Remove port after removing connector.

If PM is enabled but PM_SLEEP is disabled, the suspend/resume functions
are still unused and produce a compiler warning.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: <stable@vger.kernel.org> # 4.1+

Allow the topology code to be compiled out so that users who don't need
topology don't need to havve the code compiled in, saving them some
memory.

Some more configuration could be added to remove some of the hooks into
the core data structures but that is probably best done with some
refactoring to use functions to do the updates of the data structures
rather than ifdefing in the code as we'd need to do at the minute.
Suggested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

Pull rdma bugfix from Doug Ledford:
 "Bugfix in iw_cxgb4"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma:
  iw_cxgb4: gracefully handle unknown CQE status errors

Pull libata fixes from Tejun Heo:
 "Three minor device-specific fixes and revert of NCQ autosense added
  during this -rc1.

  It turned out that NCQ autosense as currently implemented interferes
  with the usual error handling behavior.  It will be revisited in the
  near future"

* 'for-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ata: ahci_brcmstb: Fix misuse of IS_ENABLED
  sata_sx4: Check return code from pdc20621_i2c_read()
  Revert "libata: Implement NCQ autosense"
  Revert "libata: Implement support for sense data reporting"
  Revert "libata-eh: Set 'information' field for autosense"
  ata: ahci_brcmstb: Fix warnings with CONFIG_PM_SLEEP=n

Pull cgroup fix from Tejun Heo:
 "A fix for a subtle bug introduced back during 3.17 cycle which
  interferes with setting configurations under specific conditions"

* 'for-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cpuset: use trialcs->mems_allowed as a temp variable

drivers/net/phy/smsc.c:127:3-4: Unneeded semicolon

 Remove unneeded semicolon.

Generated by: scripts/coccinelle/misc/semicolon.cocci

CC: Igor Plyatov <plyatov@gmail.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This is an HP-branded Sierra Wireless EM7355:
https://bugzilla.redhat.com/show_bug.cgi?id=1223646#c2Signed-off-by: David Ward <david.ward@ll.mit.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

VxLAN offloading is not functional if the NIC is running in multichannel
mode (UMC, FLEX-10, VNIC...). Enabling this additionally kills whole
connectivity through the NIC and the device needs to be down and up to
restore it. The firmware should take care about it and does not allow
the conversion of interface to tunnel type (be_cmd_manage_iface) or should
support VxLAN offloading if multichannel config is enabled.
I have tested this on the latest available firmware (10.6.144.21).

Result:
[root@sm-04 ~]# ip link set enp5s0f0 up[root@sm-04 ~]# ip addr add 172.30.10.50/24 dev enp5s0f0
[root@sm-04 ~]# ping -c 3 172.30.10.254PING 172.30.10.254 (172.30.10.254) 56(84) bytes of data.
64 bytes from 172.30.10.254: icmp_seq=1 ttl=64 time=0.317 ms
64 bytes from 172.30.10.254: icmp_seq=2 ttl=64 time=0.187 ms
64 bytes from 172.30.10.254: icmp_seq=3 ttl=64 time=0.188 ms

 --- 172.30.10.254 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2000ms
rtt min/avg/max/mdev = 0.187/0.230/0.317/0.063 ms
[root@sm-04 ~]# ip link add link enp5s0f0 vxlan10 type vxlan id 10 remote 172.30.10.60 dstport 4789
[root@sm-04 ~]# ip link set vxlan10 up
[ 7900.442811] be2net 0000:05:00.0: Enabled VxLAN offloads for UDP port 4789
[ 7900.455722] be2net 0000:05:00.1: Enabled VxLAN offloads for UDP port 4789
[ 7900.468635] be2net 0000:05:00.2: Enabled VxLAN offloads for UDP port 4789
[ 7900.481553] be2net 0000:05:00.3: Enabled VxLAN offloads for UDP port 4789
[root@sm-04 ~]# ping -c 3 172.30.10.254
PING 172.30.10.254 (172.30.10.254) 56(84) bytes of data.

 --- 172.30.10.254 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 1999ms

[root@sm-04 ~]# ip link set vxlan10 down
[ 7959.434093] be2net 0000:05:00.0: Disabled VxLAN offloads for UDP port 4789
[ 7959.444792] be2net 0000:05:00.1: Disabled VxLAN offloads for UDP port 4789
[ 7959.455592] be2net 0000:05:00.2: Disabled VxLAN offloads for UDP port 4789
[ 7959.466416] be2net 0000:05:00.3: Disabled VxLAN offloads for UDP port 4789
[root@sm-04 ~]# ip link del vxlan10
[root@sm-04 ~]# ping -c 3 172.30.10.254
PING 172.30.10.254 (172.30.10.254) 56(84) bytes of data.

 --- 172.30.10.254 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 1999ms

[root@sm-04 ~]# ip link set enp5s0f0 down
[root@sm-04 ~]# ip link set enp5s0f0 up
[ 8071.019003] be2net 0000:05:00.0 enp5s0f0: Link is Up
[root@sm-04 ~]# ping -c 3 172.30.10.254
PING 172.30.10.254 (172.30.10.254) 56(84) bytes of data.
64 bytes from 172.30.10.254: icmp_seq=1 ttl=64 time=0.318 ms
64 bytes from 172.30.10.254: icmp_seq=2 ttl=64 time=0.196 ms
64 bytes from 172.30.10.254: icmp_seq=3 ttl=64 time=0.194 ms

 --- 172.30.10.254 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2000ms
rtt min/avg/max/mdev = 0.194/0.236/0.318/0.057 ms

Cc: Sathya Perla <sathya.perla@avagotech.com>
Cc: Ajit Khaparde <ajit.khaparde@avagotech.com>
Cc: Padmanabh Ratnakar <padmanabh.ratnakar@avagotech.com>
Cc: Sriharsha Basavapatna <sriharsha.basavapatna@avagotech.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Acked-by: Ajit Khaparde <ajit.khaparde@avagotech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Martin KaFai Lau says:

====================
ipv6: Fix a potential deadlock when creating pcpu rt

v1 -> v2:
A minor change in the commit message of patch 2.

This patch series fixes a potential deadlock when creating a pcpu rt.
It happens when dst_alloc() decided to run gc. Something like this:

read_lock(&table->tb6_lock);
ip6_rt_pcpu_alloc()
=> dst_alloc()
=> ip6_dst_gc()
=> write_lock(&table->tb6_lock); /* oops */

Patch 1 and 2 are some prep works.
Patch 3 is the fix.

Original report: https://bugzilla.kernel.org/show_bug.cgi?id=102291
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

rt6_make_pcpu_route() is called under read_lock(&table->tb6_lock).
rt6_make_pcpu_route() calls ip6_rt_pcpu_alloc(rt) which then
calls dst_alloc().  dst_alloc() _may_ call ip6_dst_gc() which takes
the write_lock(&tabl->tb6_lock).  A visualized version:

read_lock(&table->tb6_lock);
rt6_make_pcpu_route();
=> ip6_rt_pcpu_alloc();
=> dst_alloc();
=> ip6_dst_gc();
=> write_lock(&table->tb6_lock); /* oops */

The fix is to do a read_unlock first before calling ip6_rt_pcpu_alloc().

A reported stack:

[141625.537638] INFO: rcu_sched self-detected stall on CPU { 27}  (t=60000 jiffies g=4159086 c=4159085 q=2139)
[141625.547469] Task dump for CPU 27:
[141625.550881] mtr             R  running task        0 22121  22081 0x00000008
[141625.558069]  0000000000000000 ffff88103f363d98 ffffffff8106e488 000000000000001b
[141625.565641]  ffffffff81684900 ffff88103f363db8 ffffffff810702b0 0000000008000000
[141625.573220]  ffffffff81684900 ffff88103f363de8 ffffffff8108df9f ffff88103f375a00
[141625.580803] Call Trace:
[141625.583345]  <IRQ>  [<ffffffff8106e488>] sched_show_task+0xc1/0xc6
[141625.589650]  [<ffffffff810702b0>] dump_cpu_task+0x35/0x39
[141625.595144]  [<ffffffff8108df9f>] rcu_dump_cpu_stacks+0x6a/0x8c
[141625.601320]  [<ffffffff81090606>] rcu_check_callbacks+0x1f6/0x5d4
[141625.607669]  [<ffffffff810940c8>] update_process_times+0x2a/0x4f
[141625.613925]  [<ffffffff8109fbee>] tick_sched_handle+0x32/0x3e
[141625.619923]  [<ffffffff8109fc2f>] tick_sched_timer+0x35/0x5c
[141625.625830]  [<ffffffff81094a1f>] __hrtimer_run_queues+0x8f/0x18d
[141625.632171]  [<ffffffff81094c9e>] hrtimer_interrupt+0xa0/0x166
[141625.638258]  [<ffffffff8102bf2a>] local_apic_timer_interrupt+0x4e/0x52
[141625.645036]  [<ffffffff8102c36f>] smp_apic_timer_interrupt+0x39/0x4a
[141625.651643]  [<ffffffff8140b9e8>] apic_timer_interrupt+0x68/0x70
[141625.657895]  <EOI>  [<ffffffff81346ee8>] ? dst_destroy+0x7c/0xb5
[141625.664188]  [<ffffffff813d45b5>] ? fib6_flush_trees+0x20/0x20
[141625.670272]  [<ffffffff81082b45>] ? queue_write_lock_slowpath+0x60/0x6f
[141625.677140]  [<ffffffff8140aa33>] _raw_write_lock_bh+0x23/0x25
[141625.683218]  [<ffffffff813d4553>] __fib6_clean_all+0x40/0x82
[141625.689124]  [<ffffffff813d45b5>] ? fib6_flush_trees+0x20/0x20
[141625.695207]  [<ffffffff813d6058>] fib6_clean_all+0xe/0x10
[141625.700854]  [<ffffffff813d60d3>] fib6_run_gc+0x79/0xc8
[141625.706329]  [<ffffffff813d0510>] ip6_dst_gc+0x85/0xf9
[141625.711718]  [<ffffffff81346d68>] dst_alloc+0x55/0x159
[141625.717105]  [<ffffffff813d09b5>] __ip6_dst_alloc.isra.32+0x19/0x63
[141625.723620]  [<ffffffff813d1830>] ip6_pol_route+0x36a/0x3e8
[141625.729441]  [<ffffffff813d18d6>] ip6_pol_route_output+0x11/0x13
[141625.735700]  [<ffffffff813f02c8>] fib6_rule_action+0xa7/0x1bf
[141625.741698]  [<ffffffff813d18c5>] ? ip6_pol_route_input+0x17/0x17
[141625.748043]  [<ffffffff81357c48>] fib_rules_lookup+0xb5/0x12a
[141625.754050]  [<ffffffff81141628>] ? poll_select_copy_remaining+0xf9/0xf9
[141625.761002]  [<ffffffff813f0535>] fib6_rule_lookup+0x37/0x5c
[141625.766914]  [<ffffffff813d18c5>] ? ip6_pol_route_input+0x17/0x17
[141625.773260]  [<ffffffff813d008c>] ip6_route_output+0x7a/0x82
[141625.779177]  [<ffffffff813c44c8>] ip6_dst_lookup_tail+0x53/0x112
[141625.785437]  [<ffffffff813c45c3>] ip6_dst_lookup_flow+0x2a/0x6b
[141625.791604]  [<ffffffff813ddaab>] rawv6_sendmsg+0x407/0x9b6
[141625.797423]  [<ffffffff813d7914>] ? do_ipv6_setsockopt.isra.8+0xd87/0xde2
[141625.804464]  [<ffffffff8139d4b4>] inet_sendmsg+0x57/0x8e
[141625.810028]  [<ffffffff81329ba3>] sock_sendmsg+0x2e/0x3c
[141625.815588]  [<ffffffff8132be57>] SyS_sendto+0xfe/0x143
[141625.821063]  [<ffffffff813dd551>] ? rawv6_setsockopt+0x5e/0x67
[141625.827146]  [<ffffffff8132c9f8>] ? sock_common_setsockopt+0xf/0x11
[141625.833660]  [<ffffffff8132c08c>] ? SyS_setsockopt+0x81/0xa2
[141625.839565]  [<ffffffff8140ac17>] entry_SYSCALL_64_fastpath+0x12/0x6a

Fixes: d52d3997 ("pv6: Create percpu rt6_info")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
CC: Hannes Frederic Sowa <hannes@stressinduktion.org>
Reported-by: Steinar H. Gunderson <sgunderson@bigfoot.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It is a prep work for fixing a potential deadlock when creating
a pcpu rt.

The current rt6_get_pcpu_route() will also create a pcpu rt if one does not
exist.  This patch moves the pcpu rt creation logic into another function,
rt6_make_pcpu_route().
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
CC: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

After 4b32b5ad ("ipv6: Stop rt6_info from using inet_peer's metrics"),
ip6_dst_alloc() does not need the 'table' argument.  This patch
cleans it up.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
CC: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

* Due to HW bug, LAN8700 sometimes does not detect presence of energy in the
  Ethernet cable in Energy Detect Power-Down mode (e.g while EDPWRDOWN bit is
  set, the ENERGYON bit does not asserted sometimes). This is a common bug of
  LAN87xx family of PHY chips.
* The lan87xx_read_status() was improved to acquire ENERGYON bit. Its previous
  algorythm still not reliable on 100 % and sometimes skip cable plugging.
Signed-off-by: Igor Plyatov <plyatov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>