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Author SHA1 Message Date
Stefan Sørensen
e0155950f0 dp83640: Get calibration pin with ptp_find_pin
For consistency, use the ptp_find_pin function to get the calibration pin,
not gpio_tab.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 18:52:54 -07:00
Stefan Sørensen
6f39eb87de dp83640: Verify calibration pin assignment
This constraints the pin assignment to not allow the calibration function to
be reassigned and only allow reassigning the calibratin pin if only one phy is
connected.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 18:52:53 -07:00
Stefan Sørensen
ad01577aeb dp83640: Increase supported perout pins to 7
This patch increases the number of supported periodic output pins from
1 to 7. The last pin is reserved for sync.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 18:52:53 -07:00
Stefan Sørensen
35e872ae63 dp83640: Program pulsewidth2 values of perout triggers 0 and 1
Periodic output triggers 0 and 1 of the dp83640 has a programmable
duty-cycle which is controlled by the Pulsewidth2 field of the trigger
data register.  This field is not documented in the datasheet, but it
is described in the "PHYTER Software Development Guide" section
3.1.4.1. Failing to set the field can result in unstable/no trigger
output.

Add programming of the Pulsewidth2 field, setting it to the same value
as the Pulsewidth field for a 50% duty cycle.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 18:52:53 -07:00
Florian Fainelli
b758858c5c net: bcmgenet: do not set packet length for RX buffers
Hardware will provide this information as soon as we will start
processing incoming packets, so there is no need to set the RX buffer
length during buffer allocation.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 17:25:03 -07:00
Florian Fainelli
219575eb63 net: bcmgenet: start with carrier off
We use the PHY library which will determine the link state for us, make
sure we start with a carrier off until libphy has completed the link
training.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 17:25:02 -07:00
Florian Fainelli
0f50ce96b7 net: bcmgenet: disable clock before register_netdev
As soon as register_netdev() is called, the network device notifiers are
running which means that other parts of the kernel, or user-space
programs can call the network device ndo_open() callback and use the
interface.

Disable the Ethernet device clock before we register the network device
such that we do not create the following situation:

CPU0				CPU1
register_netdev()
				bcmgenet_open()
				clk_prepare_enable()
clk_disable_unprepare()

and leave the hardware block gated off, while we think it should be
gated on.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 17:25:02 -07:00
Florian Fainelli
16f62d9bed net: systemport: fix TX NAPI work done return value
Although we do not limit the number of packets the TX completion
function bcm_sysport_tx_reclaim() is allowed to reclaim, we were still
using its return value as-is. This means that we could hit the WARN() in
net/core/dev.c where work_done >= budget.

Make sure we do exit the NAPI context when the TX ring is empty, and
pretend there was no work to do.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 17:10:17 -07:00
Florian Fainelli
412bce83ac net: systemport: fix UniMAC reset logic
The UniMAC CMD_SW_RESET bit is not a self-clearing bit, so we need to
assert it, wait a bit and clear it manually. As a result, umac_reset()
is updated not to return any value. The previous version of the code
simply wrote 0 to the CMD register, which would make the busy-waiting
loop exit immediately, having zero effect.

By writing 0 to the CMD register, we were clearing all bits in the CMD
register, and not using the hardware reset default values which are
set on purpose.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 17:10:16 -07:00
Florian Fainelli
3b140a6788 net: systemport: do not clear IFF_MULTICAST flag
The SYSTEMPORT Ethernet MAC supports multicast just fine, it just lacks
any sort of Unicast/Broadcast/Multicasting filtering at the Ethernet MAC
level since that is handled by the front end Ethernet switch, but that
is properly handled by bcm_sysport_set_rx_mode().

Some user-space applications might be relying on the presence of this
flag to prevent using multicast sockets, this also prevents that
interface from joining the IPv6 all-router mcast group.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 17:10:16 -07:00
David S. Miller
b6fd8b7fa1 Merge branch 'bnx2x-next'
Yuval Mintz says:

====================
bnx2x: Enhancement patch series

This patch series introduces the ability to propagate link parameters
to VFs as well as control the VF link via hypervisor.

In addition, it contains 2 small improvements [one IOV-related and the
other improves performance on machines with short cache lines].

Please consider applying these patches to `net-next'.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 15:52:37 -07:00
Yuval Mintz
ebf457f931 bnx2x: Fail probe of VFs using an old incompatible driver
There are linux distributions where the inbox bnx2x driver contains SRIOV
support but doesn't contain the changes introduced in b9871bcf
"bnx2x: VF RSS support - PF side".

A VF in a VM running that distribution over a new hypervisor will access
incorrect addresses when trying to transmit packets, causing an attention
in the hypervisor and making that VF inactive until FLRed.

The driver in the VM has to ne upgraded [no real way to overcome this], but
due to the HW attention currently arising upgrading the driver in the VM
would not suffice [since the VF needs also be FLRed if the previous driver
was already loaded].

This patch causes the PF to fail the acquire message from a VF running an
old problematic driver; The VF will then gracefully fail it's probe preventing
the HW attention [and allow clean upgrade of driver in VM].

Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 15:52:30 -07:00
Dmitry Kravkov
9927b51469 bnx2x: enlarge minimal alignemnt of data offset
This improves the performance of driver on machine with L1_CACHE_SHIFT of at
most 32 bytes [HW was planned for 64-byte aligned fastpath data].

Signed-off-by: Dmitry Kravkov <Dmitry.Kravkov@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 15:52:29 -07:00
Dmitry Kravkov
6495d15a7c bnx2x: VF can report link speed
Until now VFs were oblvious to the actual configured link parameters.
This patch does 2 things:

  1. It enables a PF to inform its VF using the bulletin board of the link
     configured, and allows the VF to present that information.

  2. It adds support of `ndo_set_vf_link_state', allowing the hypervisor
     to set the VF link state.

Signed-off-by: Dmitry Kravkov <Dmitry.Kravkov@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 15:52:29 -07:00
David S. Miller
edd79ca8b3 Merge branch 'pktgen'
Jesper Dangaard Brouer says:

====================
Optimizing pktgen for single CPU performance

This series focus on optimizing "pktgen" for single CPU performance.

V2-series:
 - Removed some patches
 - Doc real reason for TX ring buffer filling up

NIC tuning for pktgen:
 http://netoptimizer.blogspot.dk/2014/06/pktgen-for-network-overload-testing.html

General overload setup according to:
 http://netoptimizer.blogspot.dk/2014/04/basic-tuning-for-network-overload.html

Hardware:
 System: CPU E5-2630
 NIC: Intel ixgbe/82599 chip

Testing done with net-next git tree on top of
 commit 6623b41944 ("Merge branch 'master' of...jkirsher/net-next")

Pktgen script exercising race condition:
 https://github.com/netoptimizer/network-testing/blob/master/pktgen/unit_test01_race_add_rem_device_loop.sh

Tool for measuring LOCK overhead:
 https://github.com/netoptimizer/network-testing/blob/master/src/overhead_cmpxchg.c
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 15:50:56 -07:00
Jesper Dangaard Brouer
8788370a1d pktgen: RCU-ify "if_list" to remove lock in next_to_run()
The if_lock()/if_unlock() in next_to_run() adds a significant
overhead, because its called for every packet in busy loop of
pktgen_thread_worker().  (Thomas Graf originally pointed me
at this lock problem).

Removing these two "LOCK" operations should in theory save us approx
16ns (8ns x 2), as illustrated below we do save 16ns when removing
the locks and introducing RCU protection.

Performance data with CLONE_SKB==100000, TX-size=512, rx-usecs=30:
 (single CPU performance, ixgbe 10Gbit/s, E5-2630)
 * Prev   : 5684009 pps --> 175.93ns (1/5684009*10^9)
 * RCU-fix: 6272204 pps --> 159.43ns (1/6272204*10^9)
 * Diff   : +588195 pps --> -16.50ns

To understand this RCU patch, I describe the pktgen thread model
below.

In pktgen there is several kernel threads, but there is only one CPU
running each kernel thread.  Communication with the kernel threads are
done through some thread control flags.  This allow the thread to
change data structures at a know synchronization point, see main
thread func pktgen_thread_worker().

Userspace changes are communicated through proc-file writes.  There
are three types of changes, general control changes "pgctrl"
(func:pgctrl_write), thread changes "kpktgend_X"
(func:pktgen_thread_write), and interface config changes "etcX@N"
(func:pktgen_if_write).

Userspace "pgctrl" and "thread" changes are synchronized via the mutex
pktgen_thread_lock, thus only a single userspace instance can run.
The mutex is taken while the packet generator is running, by pgctrl
"start".  Thus e.g. "add_device" cannot be invoked when pktgen is
running/started.

All "pgctrl" and all "thread" changes, except thread "add_device",
communicate via the thread control flags.  The main problem is the
exception "add_device", that modifies threads "if_list" directly.

Fortunately "add_device" cannot be invoked while pktgen is running.
But there exists a race between "rem_device_all" and "add_device"
(which normally don't occur, because "rem_device_all" waits 125ms
before returning). Background'ing "rem_device_all" and running
"add_device" immediately allow the race to occur.

The race affects the threads (list of devices) "if_list".  The if_lock
is used for protecting this "if_list".  Other readers are given
lock-free access to the list under RCU read sections.

Note, interface config changes (via proc) can occur while pktgen is
running, which worries me a bit.  I'm assuming proc_remove() takes
appropriate locks, to assure no writers exists after proc_remove()
finish.

I've been running a script exercising the race condition (leading me
to fix the proc_remove order), without any issues.  The script also
exercises concurrent proc writes, while the interface config is
getting removed.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 15:50:23 -07:00
Jesper Dangaard Brouer
baac167b70 pktgen: avoid expensive set_current_state() call in loop
Avoid calling set_current_state() inside the busy-loop in
pktgen_thread_worker().  In case of pkt_dev->delay, then it is still
used/enabled in pktgen_xmit() via the spin() call.

The set_current_state(TASK_INTERRUPTIBLE) uses a xchg, which implicit
is LOCK prefixed.  I've measured the asm LOCK operation to take approx
8ns on this E5-2630 CPU.  Performance increase corrolate with this
measurement.

Performance data with CLONE_SKB==100000, rx-usecs=30:
 (single CPU performance, ixgbe 10Gbit/s, E5-2630)
 * Prev:  5454050 pps --> 183.35ns (1/5454050*10^9)
 * Now:   5684009 pps --> 175.93ns (1/5684009*10^9)
 * Diff:  +229959 pps -->  -7.42ns

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 15:50:23 -07:00
Jesper Dangaard Brouer
9ceb87fcea pktgen: document tuning for max NIC performance
Using pktgen I'm seeing the ixgbe driver "push-back", due TX ring
running full.  Thus, the TX ring is artificially limiting pktgen.
(Diagnose via "ethtool -S", look for "tx_restart_queue" or "tx_busy"
counters.)

Using ixgbe, the real reason behind the TX ring running full, is due
to TX ring not being cleaned up fast enough. The ixgbe driver combines
TX+RX ring cleanups, and the cleanup interval is affected by the
ethtool --coalesce setting of parameter "rx-usecs".

Do not increase the default NIC TX ring buffer or default cleanup
interval.  Instead simply document that pktgen needs special NIC
tuning for maximum packet per sec performance.

Performance results with pktgen with clone_skb=100000.
TX ring size 512 (default), adjusting "rx-usecs":
 (Single CPU performance, E5-2630, ixgbe)
 - 3935002 pps - rx-usecs:  1 (irqs:  9346)
 - 5132350 pps - rx-usecs: 10 (irqs: 99157)
 - 5375111 pps - rx-usecs: 20 (irqs: 50154)
 - 5454050 pps - rx-usecs: 30 (irqs: 33872)
 - 5496320 pps - rx-usecs: 40 (irqs: 26197)
 - 5502510 pps - rx-usecs: 50 (irqs: 21527)

TX ring size adjusting (ethtool -G), "rx-usecs==1" (default):
 - 3935002 pps - tx-size:  512
 - 5354401 pps - tx-size:  768
 - 5356847 pps - tx-size: 1024
 - 5327595 pps - tx-size: 1536
 - 5356779 pps - tx-size: 2048
 - 5353438 pps - tx-size: 4096

Notice after commit 6f25cd47d (pktgen: fix xmit test for BQL enabled
devices) pktgen uses netif_xmit_frozen_or_drv_stopped() and ignores
the BQL "stack" pause (QUEUE_STATE_STACK_XOFF) flag.  This allow us to put
more pressure on the TX ring buffers.

It is the ixgbe_maybe_stop_tx() call that stops the transmits, and
pktgen respecting this in the call to netif_xmit_frozen_or_drv_stopped(txq).

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 15:50:23 -07:00
Jiri Pirko
5b9e7e1607 openvswitch: introduce rtnl ops stub
This stub now allows userspace to see IFLA_INFO_KIND for ovs master and
IFLA_INFO_SLAVE_KIND for slave.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 14:40:17 -07:00
Jiri Pirko
b0ab2fabb5 rtnetlink: allow to register ops without ops->setup set
So far, it is assumed that ops->setup is filled up. But there might be
case that ops might make sense even without ->setup. In that case,
forbid to newlink and dellink.

This allows to register simple rtnl link ops containing only ->kind.
That allows consistent way of passing device kind (either device-kind or
slave-kind) to userspace.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 14:40:17 -07:00
Lai Jiangshan
85327af61d workqueue: stronger test in process_one_work()
When POOL_DISASSOCIATED is cleared, the running worker's local CPU should
be the same as pool->cpu without any exception even during cpu-hotplug.

This patch changes "(proposition_A && proposition_B && proposition_C)"
to "(proposition_B && proposition_C)", so if the old compound
proposition is true, the new one must be true too. so this won't hide
any possible bug which can be hit by old test.

tj: Minor description update and dropped the obvious comment.

CC: Jason J. Herne <jjherne@linux.vnet.ibm.com>
CC: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-01 17:40:14 -04:00
Lai Jiangshan
3de5e88485 workqueue: clear POOL_DISASSOCIATED in rebind_workers()
a9ab775bca ("workqueue: directly restore CPU affinity of workers
from CPU_ONLINE") moved pool locking into rebind_workers() but left
"pool->flags &= ~POOL_DISASSOCIATED" in workqueue_cpu_up_callback().

There is nothing necessarily wrong with it, but there is no benefit
either.  Let's move it into rebind_workers() and achieve the following
benefits:

  1) better readability, POOL_DISASSOCIATED is cleared in rebind_workers()
     as expected.

  2) we can guarantee that, when POOL_DISASSOCIATED is clear, the
     running workers of the pool are on the local CPU (pool->cpu).

tj: Minor description update.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-01 17:40:14 -04:00
Russell King
1fc1263bd4 dt-bindings: ata: document ability to disable spread-spectrum clock
Add documentation of the fsl,no-spread-spectrum option.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-01 17:24:41 -04:00
Russell King
a6e726244c ata: ahci_imx: add disable for spread-spectrum
Spread-spectrum doesn't work with Cubox-i hardware, so we have to
disable this feature.  Add a DT property so that platforms can
indicate that this feature should not be enabled.

Having it as a negative property keeps existing DT files working.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-01 17:24:40 -04:00
Russell King
dcb1b29b08 dt-bindings: ata: add ahci_imx electrical properties
Add the documentation for the electrical properties for the iMX SATA
controller.  There are many values for these, and listing them would
be error prone.  Refer readers to the device documentation and driver
source code for these details.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-01 17:24:40 -04:00
Russell King
29e6941366 ata: ahci_imx: allow hardware parameters to be specified in DT
Various SATA phy parameters are board specific, and therefore need to
be configured.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-01 17:24:40 -04:00
Shawn Guo
23a7c31e4a dt-bindings: ata: create bindings for imx sata controller
To: Tejun Heo <tj@kernel.org>,linux-ide@vger.kernel.org

The Freescale i.MX SATA controller mostly conforms to the AHCI
interface, but there are some special extensions at integration level
like clocks settings and hardware parameters.

Let's create a separate bindings doc for imx sata controller, so that
more imx specific properties can be added later without messing up the
generic ahci-platform bindings.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-01 17:24:39 -04:00
Ying Xue
9bf2b8c280 net: fix some typos in comment
In commit 371121057607e3127e19b3fa094330181b5b031e("net:
QDISC_STATE_RUNNING dont need atomic bit ops") the
__QDISC_STATE_RUNNING is renamed to __QDISC___STATE_RUNNING,
but the old names existing in comment are not replaced with
the new name completely.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 14:20:32 -07:00
Zhengyu He
330d282216 core: fix typo in percpu read_mostly section
This fixes a typo that named the read_mostly section of percpu as
readmostly. It works fine with SMP because the linker script specifies
.data..percpu..readmostly. However, UP kernel builds don't have percpu
sections defined and the non-percpu version of the section is called
data..read_mostly, so .data..readmostly will float around and may break
things unexpectedly.

Looking at the original change that introduced data..percpu..readmostly
(commit c957ef2c59), it looks like this
was the original intention.

Tested: Built UP kernel and confirmed the sections got merged.

- Before the patch:
$ objdump -h vmlinux.o  | grep '\.data\.\.read.*mostly'
38 .data..read_mostly 00004418  0000000000000000  0000000000000000  00431ac0  2**6
50 .data..readmostly 00000014  0000000000000000  0000000000000000  00444000  2**3

- After the patch:
$ objdump -h vmlinux.o  | grep '\.data\.\.read.*mostly'
38 .data..read_mostly 00004438  0000000000000000  0000000000000000  00431ac0  2**6

Signed-off-by: Zhengyu He <hzy@google.com>
Signed-off-by: Filipe Brandenburger <filbranden@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-01 16:45:22 -04:00
Tejun Heo
76bb5ab8f6 cpuset: break kernfs active protection in cpuset_write_resmask()
Writing to either "cpuset.cpus" or "cpuset.mems" file flushes
cpuset_hotplug_work so that cpu or memory hotunplug doesn't end up
migrating tasks off a cpuset after new resources are added to it.

As cpuset_hotplug_work calls into cgroup core via
cgroup_transfer_tasks(), this flushing adds the dependency to cgroup
core locking from cpuset_write_resmak().  This used to be okay because
cgroup interface files were protected by a different mutex; however,
8353da1f91 ("cgroup: remove cgroup_tree_mutex") simplified the
cgroup core locking and this dependency became a deadlock hazard -
cgroup file removal performed under cgroup core lock tries to drain
on-going file operation which is trying to flush cpuset_hotplug_work
blocked on the same cgroup core lock.

The locking simplification was done because kernfs added an a lot
easier way to deal with circular dependencies involving kernfs active
protection.  Let's use the same strategy in cpuset and break active
protection in cpuset_write_resmask().  While it isn't the prettiest,
this is a very rare, likely unique, situation which also goes away on
the unified hierarchy.

The commands to trigger the deadlock warning without the patch and the
lockdep output follow.

 localhost:/ # mount -t cgroup -o cpuset xxx /cpuset
 localhost:/ # mkdir /cpuset/tmp
 localhost:/ # echo 1 > /cpuset/tmp/cpuset.cpus
 localhost:/ # echo 0 > cpuset/tmp/cpuset.mems
 localhost:/ # echo $$ > /cpuset/tmp/tasks
 localhost:/ # echo 0 > /sys/devices/system/cpu/cpu1/online

  ======================================================
  [ INFO: possible circular locking dependency detected ]
  3.16.0-rc1-0.1-default+ #7 Not tainted
  -------------------------------------------------------
  kworker/1:0/32649 is trying to acquire lock:
   (cgroup_mutex){+.+.+.}, at: [<ffffffff8110e3d7>] cgroup_transfer_tasks+0x37/0x150

  but task is already holding lock:
   (cpuset_hotplug_work){+.+...}, at: [<ffffffff81085412>] process_one_work+0x192/0x520

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #2 (cpuset_hotplug_work){+.+...}:
  ...
  -> #1 (s_active#175){++++.+}:
  ...
  -> #0 (cgroup_mutex){+.+.+.}:
  ...

  other info that might help us debug this:

  Chain exists of:
    cgroup_mutex --> s_active#175 --> cpuset_hotplug_work

   Possible unsafe locking scenario:

	 CPU0                    CPU1
	 ----                    ----
    lock(cpuset_hotplug_work);
				 lock(s_active#175);
				 lock(cpuset_hotplug_work);
    lock(cgroup_mutex);

   *** DEADLOCK ***

  2 locks held by kworker/1:0/32649:
   #0:  ("events"){.+.+.+}, at: [<ffffffff81085412>] process_one_work+0x192/0x520
   #1:  (cpuset_hotplug_work){+.+...}, at: [<ffffffff81085412>] process_one_work+0x192/0x520

  stack backtrace:
  CPU: 1 PID: 32649 Comm: kworker/1:0 Not tainted 3.16.0-rc1-0.1-default+ #7
 ...
  Call Trace:
   [<ffffffff815a5f78>] dump_stack+0x72/0x8a
   [<ffffffff810c263f>] print_circular_bug+0x10f/0x120
   [<ffffffff810c481e>] check_prev_add+0x43e/0x4b0
   [<ffffffff810c4ee6>] validate_chain+0x656/0x7c0
   [<ffffffff810c53d2>] __lock_acquire+0x382/0x660
   [<ffffffff810c57a9>] lock_acquire+0xf9/0x170
   [<ffffffff815aa13f>] mutex_lock_nested+0x6f/0x380
   [<ffffffff8110e3d7>] cgroup_transfer_tasks+0x37/0x150
   [<ffffffff811129c0>] hotplug_update_tasks_insane+0x110/0x1d0
   [<ffffffff81112bbd>] cpuset_hotplug_update_tasks+0x13d/0x180
   [<ffffffff811148ec>] cpuset_hotplug_workfn+0x18c/0x630
   [<ffffffff810854d4>] process_one_work+0x254/0x520
   [<ffffffff810875dd>] worker_thread+0x13d/0x3d0
   [<ffffffff8108e0c8>] kthread+0xf8/0x100
   [<ffffffff815acaec>] ret_from_fork+0x7c/0xb0

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Li Zefan <lizefan@huawei.com>
Tested-by: Li Zefan <lizefan@huawei.com>
2014-07-01 16:42:28 -04:00
Eric Dumazet
07b0f00964 bnx2x: fix possible panic under memory stress
While it is legal to kfree(NULL), it is not wise to use :
put_page(virt_to_head_page(NULL))

 BUG: unable to handle kernel paging request at ffffeba400000000
 IP: [<ffffffffc01f5928>] virt_to_head_page+0x36/0x44 [bnx2x]

Reported-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ariel Elior <ariel.elior@qlogic.com>
Fixes: d46d132cc0 ("bnx2x: use netdev_alloc_frag()")
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 12:20:20 -07:00
Ben Greear
d933319657 ipv6: Allow accepting RA from local IP addresses.
This can be used in virtual networking applications, and
may have other uses as well.  The option is disabled by
default.

A specific use case is setting up virtual routers, bridges, and
hosts on a single OS without the use of network namespaces or
virtual machines.  With proper use of ip rules, routing tables,
veth interface pairs and/or other virtual interfaces,
and applications that can bind to interfaces and/or IP addresses,
it is possibly to create one or more virtual routers with multiple
hosts attached.  The host interfaces can act as IPv6 systems,
with radvd running on the ports in the virtual routers.  With the
option provided in this patch enabled, those hosts can now properly
obtain IPv6 addresses from the radvd.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 12:16:24 -07:00
Ben Greear
f2a762d8a9 ipv6: Add more debugging around accept-ra logic.
This is disabled by default, just like similar debug info
already in this module.  But, makes it easier to find out
why RA is not being accepted when debugging strange behaviour.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01 12:16:24 -07:00
Rafał Miłecki
15be8e89cd b43: add more bcma cores
This adds some cores with 0x2057 radio which will be supported soon as
well as core 40 that I missed in the earlier firmware patch.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:29:39 -04:00
Rafał Miłecki
fe255b40cb b43: N-PHY: complete generic support for 0x2057 radio
It doesn't include any device (radio revision) specific code yet, so it
isn't really usable. As the commit says, it's just some generic code.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:29:39 -04:00
Rafał Miłecki
e90cf1c7ab b43: N-PHY: fixes for radio 0x2057
Enable initialization and update calibration code to fix:
b43-phy0 ERROR: Radio 0x2057 rcal timeout
b43-phy0 debug: Radio 0x2057 rccal timeout
b43-phy0 debug: Radio 0x2057 rccal timeout
b43-phy0 ERROR: Radio 0x2057 rcal timeout

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:29:39 -04:00
Andrea Merello
c1084e026b rtl818x_pci: fix pci probe returns success when it fails
There are several exit path from the PCI probe function.
Some of them, that are taken in case of errors, forget to set the "err"
variable, that is returned by the probe function.
This can lead to the kernel thinking the probe function succeeds while it
didn't, and this in turn causes extra calls to the "remove" function.

This patch fix this problem by ensuring "err" variable is assigned to a proper
non-zero value in each exit path.

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:27 -04:00
Andrea Merello
f4cf628781 rtl818x_pci: handle broken PIO mapping
All boards supported by this driver could work using PIO or MMIO for accessing
registers.
This driver tries to access HW by using MMIO, and, if this fails for somewhat
reason, the driver tries to fall back to PIO mode.

MMIO-mode is straightforward on all boards.
PIO-mode is straightforward on rtl8180 only.

On rtl8185 and rtl8187se boards not all registers are directly available in PIO
mode (they are paged).

On rtl8185 there are two pages and it is known how to switch page.
PIO mode works, except for only one access to a register out of default page,
recently added by me in the initialization code with patch:
rtl818x_pci: Fix rtl8185 excessive IFS after CTS-to-self
This can be easily fixed to work in both cases (MMIO and PIO).

On rtl8187se, for a number of reasons, there is much more work to do to fix PIO
access.
PIO access is currently broken on rtl8187se, and it never worked.

This patch fixes the said register write for rtl8185 and makes the driver to
fail cleanly if PIO mode is attempted with rtl8187se boards.

While doing this, I converted also a couple of printk(KERN_ERR) to dev_err(), in
order to make checkpatch happy.

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:27 -04:00
Andrea Merello
fe67bcd4c8 rtl8180: disable buggy rate fallback mechanism
Currently the driver configures mac80211 to provide two rates for each TX frame:
One initial rate and one alternate fallback rate, each one with its retry count.

HW does not support fully this: rtl8180 doesn't have support for rate scaling at
all, and rtl8185/rtl8187SE supports it in a way that does not fit with mac80211:
The HW does automatically fall back to the next lower rate, and only a lower
limit can be specified, so the HW may TX also on rates in between the two rates
specified by mac80211.  Furthermore only the total TX retry count can be
specified for each packet, while the number of TX attempts before scaling rate
can be configured only globally (not per each packet).

Currently the driver sets the HW auto rate fallback mechanism to quickly scale
rate after a couple of retries, and it uses the alternate rate requested by
mac80211 as fallback limit rate (and it does this even wrongly).

The HW indeed will behave differently than what mac80211 mandates, that is
probably undesirable, and the reported TX retry count may not refer to what
mac80211 thinks, and this could fool mac80211.

This patch makes the driver to declare to mac80211 to support only one rate
configuration for each packet, and it does disable the HW auto rate fallback
mechanism, relying only on SW and letting mac80211 to do all by itself.

This should ensure correct operation and fairness respect to mac80211.
Indeed here tests with iperf do not show significant performance differences.

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:27 -04:00
Andrea Merello
81129fce7e rtl8180: fix incorrect TX retry.
HW is programmed with wrong retry count value for TX:

Mac80211 passes to driver the number of times the TX should be attempted.
The HW, instead, wants the number of time the TX should be retried if it fails
the first time (assuming we have to TX it at least one time).

This patch correct this.

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:27 -04:00
Andrea Merello
f82be7c46a rtl818x_pci: add comment pointing to the rtl8187se reference code
Rtl8187se support has been added to the rtl818x_pci driver by extracting a lot
of information from a rtl8187se Linux staging driver included in the kernel at
the time rtl8187se support was added.
The rtl818x_pci main file has a comment that advertises this.

Recently this staging driver has been removed from the kernel, but I still feel
it can be useful as "reference" code (in case of bugs, or to implement
improvements in rtl818x_pci driver).

This one-line patch adds a comment in rtl818x_pci driver to point people
searching for that "reference code" to the last kernel version still containing
it (3.14).

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:27 -04:00
Andrea Merello
7df007243b rtl818x_pci: Fix rtl8185 excessive IFS after CTS-to-self
Measuring time between _end_ of CTS-to-self and _end_ of datapacket (with a
prism54 board and mac80211 hacked to let the MAC timestamp stay untouched in the
radiotap header) resulted in about 300uS, while the datapacket itself should be
by far shorter (less than 100uS) and IFS should be SIFS (10uS).
This measure was confirmed whith a scope: about 250uS IFS has been seen between
the two packets.

This situation causes the CTS-to-self protection mechanism to work incorrectly
due to the NAV expiring during, or even before beginning, the packet
transmission, and it also causes the performances to be anyway reduced due to
time waste.

This problem has been seen at every packet TXed with CTS-to-self enabled on
rtl8185 board.
rtl8187se seems not affected (and rtl8180, being a 802.11b card, does not have
CTS-to-self mechaninsm).

This patch fixes this by adding a magic register write, making the board wait
for correct SIFS after CTS-to-self packet.

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:27 -04:00
Andrea Merello
1f622d76fa rtl818x_pci: Fix BSSID register written incorrectly
BSSID register was written with six byte-writes.
It seems that, similarly to what happens with MAC registers, they needs to be
written with one 16-bit and one 32-bit writes, otherwise the write does not work.

The byte write didn't work only on my rtl8185, while it worked on rtl8180 and
rtl8187se, BTW since there are probably a number of different ASIC revisions out
of there, I let the change to affect all cards.
It shouldn't hurt anyway.

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:26 -04:00
Rafał Miłecki
b49c3caf5e b43: treat LCNXN-PHY as extra N-PHY devices
LCNXN is simply a continuation of N, e.g. code handling LCNXN revs 0 and
1 is mostly the same as for N-PHY revs 7+.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:26 -04:00
Fabian Frederick
f528f664d6 drivers/net/wireless/ipw2x00/libipw_module.c: remove unnecessary null test before kfree
Fix checkpatch warning:
WARNING: kfree(NULL) is safe this check is probably not required

Cc: Stanislav Yakovlev <stas.yakovlev@gmail.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: linux-wireless@vger.kernel.org
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:26 -04:00
Alexey Khoroshilov
50591c60a9 rsi: fix memory leaks and error handling in rsi_91x_usb
The patch fixes a couple of issues:
- absence of deallocation of rsi_dev->rx_usb_urb[0] in the driver;
- potential NULL pointer dereference because of lack of checks for memory
  allocation success in rsi_init_usb_interface().

By the way, it makes rsi_probe() returning error code instead of 1
and fixes comments regarding returning values.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:26 -04:00
Alexey Khoroshilov
5bc5ca85d5 rsi: GFP_ATOMIC is not needed in rsi_init_usb_interface()
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:26 -04:00
Rajkumar Manoharan
09ebb81092 ath9k: Calculate sleep duration
Right now sleep duration is configured as beacon interval. It should be
the multiple of beacon interval by listen period which helps to
reduce station power consumption.

Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:26 -04:00
Rajkumar Manoharan
5f2f9e44ba ath9k: Increase max listen interval
Earlier the listen interval is used to decide switching between
operating and off-channels during bgscan and to improve throughput,
the listen interval is reduced to 1. After optimiztion in scan
state machine, listen period is not used for decision making and
hence reverting it back to original value.

Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:26 -04:00
Rajkumar Manoharan
9198cf4a84 ath9k: Cache beacon config after association
The beacon configurations are not cached properly after the station
associates with AP. Not handling BEACON_INFO, is failing to update
dtim period and also it is causing below warning message.

WARNING: CPU: 1 PID: 0 at drivers/net/wireless/ath/ath9k/recv.c:548
ath_rx_tasklet+0xc89/0xca0 [ath9k]()
 Call Trace:
  [<c14669c9>] dump_stack+0x48/0x69
  [<c104f1a2>] warn_slowpath_common+0x82/0xa0
  [<fd38c2f9>] ? ath_rx_tasklet+0xc89/0xca0 [ath9k]
  [<fd38c2f9>] ? ath_rx_tasklet+0xc89/0xca0 [ath9k]

Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-07-01 14:26:25 -04:00