Commit Graph

506321 Commits

Author SHA1 Message Date
David Vrabel c8a4d29988 xen-netback: notify immediately after pushing Tx response.
This fixes a performance regression introduced by
7fbb9d8415 (xen-netback: release pending
index before pushing Tx responses)

Moving the notify outside of the spin locks means it can be delayed a
long time (if the dealloc thread is descheduled or there is an
interrupt or softirq).

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Zoltan Kiss <zoltan.kiss@linaro.org>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-11 23:30:44 -04:00
Alexey Kodanev b1cb59cf2e net: sysctl_net_core: check SNDBUF and RCVBUF for min length
sysctl has sysctl.net.core.rmem_*/wmem_* parameters which can be
set to incorrect values. Given that 'struct sk_buff' allocates from
rcvbuf, incorrectly set buffer length could result to memory
allocation failures. For example, set them as follows:

    # sysctl net.core.rmem_default=64
      net.core.wmem_default = 64
    # sysctl net.core.wmem_default=64
      net.core.wmem_default = 64
    # ping localhost -s 1024 -i 0 > /dev/null

This could result to the following failure:

skbuff: skb_over_panic: text:ffffffff81628db4 len:-32 put:-32
head:ffff88003a1cc200 data:ffff88003a1cc200 tail:0xffffffe0 end:0xc0 dev:<NULL>
kernel BUG at net/core/skbuff.c:102!
invalid opcode: 0000 [#1] SMP
...
task: ffff88003b7f5550 ti: ffff88003ae88000 task.ti: ffff88003ae88000
RIP: 0010:[<ffffffff8155fbd1>]  [<ffffffff8155fbd1>] skb_put+0xa1/0xb0
RSP: 0018:ffff88003ae8bc68  EFLAGS: 00010296
RAX: 000000000000008d RBX: 00000000ffffffe0 RCX: 0000000000000000
RDX: ffff88003fdcf598 RSI: ffff88003fdcd9c8 RDI: ffff88003fdcd9c8
RBP: ffff88003ae8bc88 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 00000000000002b2 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88003d3f7300 R15: ffff88000012a900
FS:  00007fa0e2b4a840(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000d0f7e0 CR3: 000000003b8fb000 CR4: 00000000000006f0
Stack:
 ffff88003a1cc200 00000000ffffffe0 00000000000000c0 ffffffff818cab1d
 ffff88003ae8bd68 ffffffff81628db4 ffff88003ae8bd48 ffff88003b7f5550
 ffff880031a09408 ffff88003b7f5550 ffff88000012aa48 ffff88000012ab00
Call Trace:
 [<ffffffff81628db4>] unix_stream_sendmsg+0x2c4/0x470
 [<ffffffff81556f56>] sock_write_iter+0x146/0x160
 [<ffffffff811d9612>] new_sync_write+0x92/0xd0
 [<ffffffff811d9cd6>] vfs_write+0xd6/0x180
 [<ffffffff811da499>] SyS_write+0x59/0xd0
 [<ffffffff81651532>] system_call_fastpath+0x12/0x17
Code: 00 00 48 89 44 24 10 8b 87 c8 00 00 00 48 89 44 24 08 48 8b 87 d8 00
      00 00 48 c7 c7 30 db 91 81 48 89 04 24 31 c0 e8 4f a8 0e 00 <0f> 0b
      eb fe 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 48 83
RIP  [<ffffffff8155fbd1>] skb_put+0xa1/0xb0
RSP <ffff88003ae8bc68>
Kernel panic - not syncing: Fatal exception

Moreover, the possible minimum is 1, so we can get another kernel panic:
...
BUG: unable to handle kernel paging request at ffff88013caee5c0
IP: [<ffffffff815604cf>] __alloc_skb+0x12f/0x1f0
...

Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-11 21:25:13 -04:00
Neal Cardwell d578e18ce9 tcp: restore 1.5x per RTT limit to CUBIC cwnd growth in congestion avoidance
Commit 814d488c61 ("tcp: fix the timid additive increase on stretch
ACKs") fixed a bug where tcp_cong_avoid_ai() would either credit a
connection with an increase of snd_cwnd_cnt, or increase snd_cwnd, but
not both, resulting in cwnd increasing by 1 packet on at most every
alternate invocation of tcp_cong_avoid_ai().

Although the commit correctly implemented the CUBIC algorithm, which
can increase cwnd by as much as 1 packet per 1 packet ACKed (2x per
RTT), in practice that could be too aggressive: in tests on network
paths with small buffers, YouTube server retransmission rates nearly
doubled.

This commit restores CUBIC to a maximum cwnd growth rate of 1 packet
per 2 packets ACKed (1.5x per RTT). In YouTube tests this restored
retransmit rates to low levels.

Testing: This patch has been tested in datacenter netperf transfers
and live youtube.com and google.com servers.

Fixes: 9cd981dcf1 ("tcp: fix stretch ACK bugs in CUBIC")
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-11 16:51:51 -04:00
Neal Cardwell 9949afa42b tcp: fix tcp_cong_avoid_ai() credit accumulation bug with decreases in w
The recent change to tcp_cong_avoid_ai() to handle stretch ACKs
introduced a bug where snd_cwnd_cnt could accumulate a very large
value while w was large, and then if w was reduced snd_cwnd could be
incremented by a large delta, leading to a large burst and high packet
loss. This was tickled when CUBIC's bictcp_update() sets "ca->cnt =
100 * cwnd".

This bug crept in while preparing the upstream version of
814d488c61.

Testing: This patch has been tested in datacenter netperf transfers
and live youtube.com and google.com servers.

Fixes: 814d488c61 ("tcp: fix the timid additive increase on stretch ACKs")
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-11 16:51:51 -04:00
chas williams - CONTRACTOR 366c1bd191 MAINTAINERS: Update my email address
Changed to my private email address.

Signed-off-by: Chas Williams -- CONTRACTOR <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-11 16:48:56 -04:00
David S. Miller 4363890079 net: Handle unregister properly when netdev namespace change fails.
If rtnl_newlink() fails on it's call to dev_change_net_namespace(), we
have to make use of the ->dellink() method, if present, just like we
do when rtnl_configure_link() fails.

Fixes: 317f4810e4 ("rtnl: allow to create device with IFLA_LINK_NETNSID set")
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-10 21:59:46 -04:00
Oliver Hartkopp 7768eed8bf net: add comment for sock_efree() usage
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-10 16:12:20 -04:00
David S. Miller 3f39d6257b Merge tag 'wireless-drivers-for-davem-2015-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers
iwlwifi:

* fix ROC removal - avoids a firmware crash
* fix throughput regression on iwldvm devices
* fix panic in BT Coex
* fixes in rate control
* fixes in scan

b43:

* fix support for 5 GHz only BCM43228 model

rtlwifi:

* improve handling of IPv6 packets

brcmfmac:

* perform bound checking on vendor command buffer

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-10 13:43:02 -04:00
Hariprasad Shenai e3d50738e5 cxgb4: fix coccinelle warnings
Commit 16e47624e7 ("cxgb4: Add new scheme to update T4/T5 firmware")
introduced below coccinelle warning.

>> drivers/net/ethernet/chelsio/cxgb4/t4_hw.c:994:2-8: Replace memcpy with
   struct assignment

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-10 13:42:00 -04:00
Nimrod Andy af5cbc9822 net: fec: fix receive VLAN CTAG HW acceleration issue
The current driver support receive VLAN CTAG HW acceleration feature
(NETIF_F_HW_VLAN_CTAG_RX) through software simulation. There calls the
api .skb_copy_to_linear_data_offset() to skip the VLAN tag, but there
have overlap between the two memory data point range. The patch just fix
the issue.

V2:
Michael Grzeschik suggest to use memmove() instead of skb_copy_to_linear_data_offset().

Reported-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Fixes: 1b7bde6d65 ("net: fec: implement rx_copybreak to improve rx performance")
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-10 13:37:01 -04:00
Yongbae Park 5a3dba7a5f net: WIZnet drivers: enable interrupts after napi_complete()
The interrupt is enabled before napi_complete(). A network timeout
occurs if the interrupt handler is called before napi_complete().

Fix the bug by enabling the interrupt after napi_complete().

Signed-off-by: Yongbae Park <yongbae2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-10 00:22:54 -04:00
Yongbae Park 4736edc764 ibmveth: enable interrupts after napi_complete()
The interrupt is enabled before napi_complete(). A network timeout
occurs if the interrupt handler is called before napi_complete().

Fix the bug by enabling the interrupt after napi_complete().

Signed-off-by: Yongbae Park <yongbae2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-10 00:22:22 -04:00
WANG Cong 5778d39d07 net_sched: fix struct tc_u_hnode layout in u32
We dynamically allocate divisor+1 entries for ->ht[] in tc_u_hnode:

  ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);

So ->ht is supposed to be the last field of this struct, however
this is broken, since an rcu head is appended after it.

Fixes: 1ce87720d4 ("net: sched: make cls_u32 lockless")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-09 23:44:31 -04:00
Linus Torvalds affb8172de Merge git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm/s390 bugfixes from Marcelo Tosatti.

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: s390: non-LPAR case obsolete during facilities mask init
  KVM: s390: include guest facilities in kvm facility test
  KVM: s390: fix in memory copy of facility lists
  KVM: s390/cpacf: Fix kernel bug under z/VM
  KVM: s390/cpacf: Enable key wrapping by default
2015-03-09 18:59:50 -07:00
Linus Torvalds ec0e6bd3f1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Martin Schwidefsky:
 "One performance optimization for page_clear and a couple of bug fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/mm: fix incorrect ASCE after crst_table_downgrade
  s390/ftrace: fix crashes when switching tracers / add notrace to cpu_relax()
  s390/pci: unify pci_iomap symbol exports
  s390/pci: fix [un]map_resources sequence
  s390: let the compiler do page clearing
  s390/pci: fix possible information leak in mmio syscall
  s390/dcss: array index 'i' is used before limits check.
  s390/scm_block: fix off by one during cluster reservation
  s390/jump label: improve and fix sanity check
  s390/jump label: add missing jump_label_apply_nops() call
2015-03-09 18:55:52 -07:00
Linus Torvalds e7901af143 Merge tag 'trace-fixes-v4.0-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull seq-buf/ftrace fixes from Steven Rostedt:
 "This includes fixes for seq_buf_bprintf() truncation issue.  It also
  contains fixes to ftrace when /proc/sys/kernel/ftrace_enabled and
  function tracing are started.  Doing the following causes some issues:

    # echo 0 > /proc/sys/kernel/ftrace_enabled
    # echo function_graph > /sys/kernel/debug/tracing/current_tracer
    # echo 1 > /proc/sys/kernel/ftrace_enabled
    # echo nop > /sys/kernel/debug/tracing/current_tracer
    # echo function_graph > /sys/kernel/debug/tracing/current_tracer

  As well as with function tracing too.  Pratyush Anand first reported
  this issue to me and supplied a patch.  When I tested this on my x86
  test box, it caused thousands of backtraces and warnings to appear in
  dmesg, which also caused a denial of service (a warning for every
  function that was listed).  I applied Pratyush's patch but it did not
  fix the issue for me.  I looked into it and found a slight problem
  with trampoline accounting.  I fixed it and sent Pratyush a patch, but
  he said that it did not fix the issue for him.

  I later learned tha Pratyush was using an ARM64 server, and when I
  tested on my ARM board, I was able to reproduce the same issue as
  Pratyush.  After applying his patch, it fixed the problem.  The above
  test uncovered two different bugs, one in x86 and one in ARM and
  ARM64.  As this looked like it would affect PowerPC, I tested it on my
  PPC64 box.  It too broke, but neither the patch that fixed ARM or x86
  fixed this box (the changes were all in generic code!).  The above
  test, uncovered two more bugs that affected PowerPC.  Again, the
  changes were only done to generic code.  It's the way the arch code
  expected things to be done that was different between the archs.  Some
  where more sensitive than others.

  The rest of this series fixes the PPC bugs as well"

* tag 'trace-fixes-v4.0-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix ftrace enable ordering of sysctl ftrace_enabled
  ftrace: Fix en(dis)able graph caller when en(dis)abling record via sysctl
  ftrace: Clear REGS_EN and TRAMP_EN flags on disabling record via sysctl
  seq_buf: Fix seq_buf_bprintf() truncation
  seq_buf: Fix seq_buf_vprintf() truncation
2015-03-09 18:44:06 -07:00
Linus Torvalds 36bef88380 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) nft_compat accidently truncates ethernet protocol to 8-bits, from
    Arturo Borrero.

 2) Memory leak in ip_vs_proc_conn(), from Julian Anastasov.

 3) Don't allow the space required for nftables rules to exceed the
    maximum value representable in the dlen field.  From Patrick
    McHardy.

 4) bcm63xx_enet can accidently leave interrupts permanently disabled
    due to errors in the NAPI polling exit logic.  Fix from Nicolas
    Schichan.

 5) Fix OOPSes triggerable by the ping protocol module, due to missing
    address family validations etc.  From Lorenzo Colitti.

 6) Don't use RCU locking in sleepable context in team driver, from Jiri
    Pirko.

 7) xen-netback miscalculates statistic offset pointers when reporting
    the stats to userspace.  From David Vrabel.

 8) Fix a leak of up to 256 pages per VIF destroy in xen-netaback, also
    from David Vrabel.

 9) ip_check_defrag() cannot assume that skb_network_offset(),
    particularly when it is used by the AF_PACKET fanout defrag code.
    From Alexander Drozdov.

10) gianfar driver doesn't query OF node names properly when trying to
    determine the number of hw queues available.  Fix it to explicitly
    check for OF nodes named queue-group.  From Tobias Waldekranz.

11) MID field in macb driver should be 12 bits, not 16.  From Punnaiah
    Choudary Kalluri.

12) Fix unintentional regression in traceroute due to timestamp socket
    option changes.  Empty ICMP payloads should be allowed in
    non-timestamp cases.  From Willem de Bruijn.

13) When devices are unregistered, we have to get rid of AF_PACKET
    multicast list entries that point to it via ifindex.  Fix from
    Francesco Ruggeri.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (38 commits)
  tipc: fix bug in link failover handling
  net: delete stale packet_mclist entries
  net: macb: constify macb configuration data
  MAINTAINERS: add Marc Kleine-Budde as co maintainer for CAN networking layer
  MAINTAINERS: linux-can moved to github
  can: kvaser_usb: Read all messages in a bulk-in URB buffer
  can: kvaser_usb: Avoid double free on URB submission failures
  can: peak_usb: fix missing ctrlmode_ init for every dev
  can: add missing initialisations in CAN related skbuffs
  ip: fix error queue empty skb handling
  bgmac: Clean warning messages
  tcp: align tcp_xmit_size_goal() on tcp_tso_autosize()
  net: fec: fix unbalanced clk disable on driver unbind
  net: macb: Correct the MID field length value
  net: gianfar: correctly determine the number of queue groups
  ipv4: ip_check_defrag should not assume that skb_network_offset is zero
  net: bcmgenet: properly disable password matching
  net: eth: xgene: fix booting with devicetree
  bnx2x: Force fundamental reset for EEH recovery
  xen-netback: refactor xenvif_handle_frag_list()
  ...
2015-03-09 18:17:21 -07:00
Linus Torvalds e93df634aa Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input subsystem fixes from Dmitry Torokhov:
 "Miscellaneous driver fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: psmouse - disable "palm detection" in the focaltech driver
  Input: psmouse - disable changing resolution/rate/scale for FocalTech
  Input: psmouse - ensure that focaltech reports consistent coordinates
  Input: psmouse - remove hardcoded touchpad size from the focaltech driver
  Input: tc3589x-keypad - set IRQF_ONESHOT flag to ensure IRQ request
  Input: ALPS - fix memory leak when detection fails
  Input: sun4i-ts - add thermal driver dependency
  Input: cyapa - remove superfluous type check in cyapa_gen5_read_idac_data()
  Input: cyapa - fix unaligned functions redefinition error
  Input: mma8450 - add parent device
2015-03-09 18:06:13 -07:00
Linus Torvalds 068c65c557 Merge tag 'regulator-v4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator fixes from Mark Brown:
 "A couple of driver specific fixes plus a fix for a regression in the
  core where the updates to use sysfs group registration were overly
  enthusiastic in eliding properties and removed some that had been
  previously present"

* tag 'regulator-v4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: Fix regression due to NULL constraints check
  regulator: rk808: Set the enable time for LDOs
  regulator: da9210: Mask all interrupt sources to deassert interrupt line
2015-03-09 18:00:25 -07:00
Linus Torvalds d08edd8f09 Merge tag 'spi-v4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
 "A collection of driver specific fixes to which the usual comments
  about them being important if you see them mostly apply (except for
  the comment fix).  The pl022 one is particularly nasty for anyone
  affected by it"

* tag 'spi-v4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: pl022: Fix race in giveback() leading to driver lock-up
  spi: dw-mid: avoid potential NULL dereference
  spi: img-spfi: Verify max spfi transfer length
  spi: fix a typo in comment.
  spi: atmel: Fix interrupt setup for PDC transfers
  spi: dw: revisit FIFO size detection again
  spi: dw-pci: correct number of chip selects
  drivers: spi: ti-qspi: wait for busy bit clear before data write/read
2015-03-09 17:50:02 -07:00
Linus Torvalds eca8dac4fa Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull tpm fixes from James Morris:
 "fixes for the TPM driver"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  tpm: fix call order in tpm-chip.c
  tpm/ibmvtpm: Additional LE support for tpm_ibmvtpm_send
2015-03-09 17:45:34 -07:00
Linus Torvalds ecddad64d4 Merge tag 'fbdev-fixes-4.0' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux
Pull fbdev fixes from Tomi Valkeinen:
 - Fix regression in with omapdss when using i2c displays
 - Fix possible null deref in fbmon
 - Check kalloc return value in AMBA CLCD

* tag 'fbdev-fixes-4.0' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux:
  OMAPDSS: fix regression with display sysfs files
  video: fbdev: fix possible null dereference
  video: ARM CLCD: Add missing error check for devm_kzalloc
2015-03-09 17:35:29 -07:00
Linus Torvalds c0e99a71bd Merge branch 'for-4.0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "The cgroup iteration update two years ago and the recent cpuset
  restructuring introduced regressions in subset of cpuset
  configurations.  Three patches to fix them.

  All are marked for -stable"

* 'for-4.0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cpuset: Fix cpuset sched_relax_domain_level
  cpuset: fix a warning when clearing configured masks in old hierarchy
  cpuset: initialize effective masks when clone_children is enabled
2015-03-09 17:30:09 -07:00
Linus Torvalds f930713b6b Merge branch 'for-4.0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Pull libata fixlet from Tejun Heo:
 "Speed limiting fix for sata_fsl"

* 'for-4.0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  sata-fsl: Apply link speed limits
2015-03-09 17:23:30 -07:00
Linus Torvalds b695f31f4e Merge branch 'for-4.0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fix from Tejun Heo:
 "One fix patch for a subtle livelock condition which can happen on
  PREEMPT_NONE kernels involving two racing cancel_work calls.  Whoever
  comes in the second has to wait for the previous one to finish.  This
  was implemented by making the later one block for the same condition
  that the former would be (work item completion) and then loop and
  retest; unfortunately, depending on the wake up order, the later one
  could lock out the former one to finish by busy looping on the cpu.

  This is fixed by implementing explicit wait mechanism.  Work item
  might not belong anywhere at this point and there's remote possibility
  of thundering herd problem.  I originally tried to use bit_waitqueue
  but it didn't work for static work items on modules.  It's currently
  using single wait queue with filtering wake up function and exclusive
  wakeup.  If this ever becomes a problem, which is not very likely, we
  can try to figure out a way to piggy back on bit_waitqueue"

* 'for-4.0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix hang involving racing cancel[_delayed]_work_sync()'s for PREEMPT_NONE
2015-03-09 17:00:54 -07:00