Commit Graph

377217 Commits

Author SHA1 Message Date
Sergei Shtylyov
9f8c4265bd sh_eth: fix result of sh_eth_check_reset() on timeout
When  the first loop in sh_eth_check_reset() runs to its end, 'cnt' is 0, so the
following check for 'cnt < 0' fails to catch the timeout.  Fix the  condition in
this check, so that the timeout  is actually reported.
While at it, fix the grammar in the failure message...

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-11 02:28:48 -07:00
Sebastian Siewior
2786aae7fc net/ti davinci_mdio: don't hold a spin lock while calling pm_runtime
was playing with suspend and run into this:

|BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:891
|in_atomic(): 1, irqs_disabled(): 0, pid: 1963, name: bash
|6 locks held by bash/1963:
|CPU: 0 PID: 1963 Comm: bash Not tainted 3.10.0-rc4+ #50
|[<c0014fdc>] (unwind_backtrace+0x0/0xf8) from [<c0011da4>] (show_stack+0x10/0x14)
|[<c0011da4>] (show_stack+0x10/0x14) from [<c02e8680>] (__pm_runtime_idle+0xa4/0xac)
|[<c02e8680>] (__pm_runtime_idle+0xa4/0xac) from [<c0341158>] (davinci_mdio_suspend+0x6c/0x9c)
|[<c0341158>] (davinci_mdio_suspend+0x6c/0x9c) from [<c02e0628>] (platform_pm_suspend+0x2c/0x54)
|[<c02e0628>] (platform_pm_suspend+0x2c/0x54) from [<c02e52bc>] (dpm_run_callback.isra.3+0x2c/0x64)
|[<c02e52bc>] (dpm_run_callback.isra.3+0x2c/0x64) from [<c02e57e4>] (__device_suspend+0x100/0x22c)
|[<c02e57e4>] (__device_suspend+0x100/0x22c) from [<c02e67e8>] (dpm_suspend+0x68/0x230)
|[<c02e67e8>] (dpm_suspend+0x68/0x230) from [<c0072a20>] (suspend_devices_and_enter+0x68/0x350)
|[<c0072a20>] (suspend_devices_and_enter+0x68/0x350) from [<c0072f18>] (pm_suspend+0x210/0x24c)
|[<c0072f18>] (pm_suspend+0x210/0x24c) from [<c0071c74>] (state_store+0x6c/0xbc)
|[<c0071c74>] (state_store+0x6c/0xbc) from [<c02714dc>] (kobj_attr_store+0x14/0x20)
|[<c02714dc>] (kobj_attr_store+0x14/0x20) from [<c01341a0>] (sysfs_write_file+0x16c/0x19c)
|[<c01341a0>] (sysfs_write_file+0x16c/0x19c) from [<c00ddfe4>] (vfs_write+0xb4/0x190)
|[<c00ddfe4>] (vfs_write+0xb4/0x190) from [<c00de3a4>] (SyS_write+0x3c/0x70)
|[<c00de3a4>] (SyS_write+0x3c/0x70) from [<c000e2c0>] (ret_fast_syscall+0x0/0x48)

I don't see a reason why the pm_runtime call must be under the lock.
Further I don't understand why this is a spinlock and not mutex.

Cc: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-11 02:26:01 -07:00
Scott Wood
7c11c0ccc7 kvm/ppc/booke64: Fix lazy ee handling in kvmppc_handle_exit()
EE is hard-disabled on entry to kvmppc_handle_exit(), so call
hard_irq_disable() so that PACA_IRQ_HARD_DIS is set, and soft_enabled
is unset.

Without this, we get warnings such as arch/powerpc/kernel/time.c:300,
and sometimes host kernel hangs.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-11 11:11:00 +03:00
Scott Wood
f1e89028f0 kvm/ppc/booke: Hold srcu lock when calling gfn functions
KVM core expects arch code to acquire the srcu lock when calling
gfn_to_memslot and similar functions.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-11 11:10:59 +03:00
Scott Wood
2b6398fcf2 kvm/ppc/booke64: Disable e6500 support
The previous patch made 64-bit booke KVM build again, but Altivec
support is still not complete, and we can't prevent the guest from
turning on Altivec (which can corrupt host state until state
save/restore is implemented).  Disable e6500 on KVM until this is
fixed.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-11 11:10:56 +03:00
Mihai Caraman
4edd1ae91b kvm/ppc/booke64: Fix AltiVec interrupt numbers and build breakage
Interrupt numbers defined for Book3E follows IVORs definition. Align
BOOKE_INTERRUPT_ALTIVEC_UNAVAIL and BOOKE_INTERRUPT_ALTIVEC_ASSIST to this
rule which also fixes the build breakage.
IVORs 32 and 33 are shared so reflect this in the interrupts naming.

This fixes a build break for 64-bit booke KVM.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-11 11:10:49 +03:00
Tomasz Figa
cd3fc1b9a3 ARM: SAMSUNG: pm: Adjust for pinctrl- and DT-enabled platforms
This patch makes legacy code on suspend/resume path being executed
conditionally, on non-DT platforms only, to fix suspend/resume of
DT-enabled systems, for which the code is inappropriate.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
[olof: add #include <linux/of.h>]
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-06-11 01:10:12 -07:00
David Daney
681865d48e mips/kvm: Use KVM_REG_MIPS and proper size indicators for *_ONE_REG
The API requires that the GET_ONE_REG and SET_ONE_REG ioctls have this
extra information encoded in the register identifiers.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-11 11:07:38 +03:00
David Daney
2a8fedd0c1 kvm: Add definition of KVM_REG_MIPS
We use 0x7000000000000000ULL as 0x6000000000000000ULL is reserved for
ARM64.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-11 11:06:34 +03:00
Haojian Zhuang
7e5955db45 ARM: prima2: fix incorrect panic usage
In prima2, some functions of checking DT is registered in initcall
level. If it doesn't match the compatible name of sirf, kernel
will panic. It blocks the usage of multiplatform on other verndor.

The error message is in below.

Knic - not syncing: unable to find compatible pwrc node in dtb
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0-rc3-00006-gd7f26ea-dirty #86
[<c0013adc>] (unwind_backtrace+0x0/0xf8) from [<c0011430>] (show_stack+0x10/0x1)
[<c0011430>] (show_stack+0x10/0x14) from [<c026f724>] (panic+0x90/0x1e8)
[<c026f724>] (panic+0x90/0x1e8) from [<c03267fc>] (sirfsoc_of_pwrc_init+0x24/0x)
[<c03267fc>] (sirfsoc_of_pwrc_init+0x24/0x58) from [<c0320864>] (do_one_initcal)
[<c0320864>] (do_one_initcall+0x90/0x150) from [<c0320a20>] (kernel_init_freeab)
[<c0320a20>] (kernel_init_freeable+0xfc/0x1c4) from [<c026b9e8>] (kernel_init+0)
[<c026b9e8>] (kernel_init+0x8/0xe4) from [<c000e158>] (ret_from_fork+0x14/0x3c)

Signen-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-06-11 00:11:31 -07:00
Nicolas Dichtel
ed13998c31 sock_diag: fix filter code sent to userspace
Filters need to be translated to real BPF code for userland, like SO_GETFILTER.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-10 22:23:32 -07:00
Ben Greear
34376a50fb Fix lockup related to stop_machine being stuck in __do_softirq.
The stop machine logic can lock up if all but one of the migration
threads make it through the disable-irq step and the one remaining
thread gets stuck in __do_softirq.  The reason __do_softirq can hang is
that it has a bail-out based on jiffies timeout, but in the lockup case,
jiffies itself is not incremented.

To work around this, re-add the max_restart counter in __do_irq and stop
processing irqs after 10 restarts.

Thanks to Tejun Heo and Rusty Russell and others for helping me track
this down.

This was introduced in 3.9 by commit c10d73671a ("softirq: reduce
latencies").

It may be worth looking into ath9k to see if it has issues with its irq
handler at a later date.

The hang stack traces look something like this:

    ------------[ cut here ]------------
    WARNING: at kernel/watchdog.c:245 watchdog_overflow_callback+0x9c/0xa7()
    Watchdog detected hard LOCKUP on cpu 2
    Modules linked in: ath9k ath9k_common ath9k_hw ath mac80211 cfg80211 nfsv4 auth_rpcgss nfs fscache nf_nat_ipv4 nf_nat veth 8021q garp stp mrp llc pktgen lockd sunrpc]
    Pid: 23, comm: migration/2 Tainted: G         C   3.9.4+ #11
    Call Trace:
     <NMI>   warn_slowpath_common+0x85/0x9f
      warn_slowpath_fmt+0x46/0x48
      watchdog_overflow_callback+0x9c/0xa7
      __perf_event_overflow+0x137/0x1cb
      perf_event_overflow+0x14/0x16
      intel_pmu_handle_irq+0x2dc/0x359
      perf_event_nmi_handler+0x19/0x1b
      nmi_handle+0x7f/0xc2
      do_nmi+0xbc/0x304
      end_repeat_nmi+0x1e/0x2e
     <<EOE>>
      cpu_stopper_thread+0xae/0x162
      smpboot_thread_fn+0x258/0x260
      kthread+0xc7/0xcf
      ret_from_fork+0x7c/0xb0
    ---[ end trace 4947dfa9b0a4cec3 ]---
    BUG: soft lockup - CPU#1 stuck for 22s! [migration/1:17]
    Modules linked in: ath9k ath9k_common ath9k_hw ath mac80211 cfg80211 nfsv4 auth_rpcgss nfs fscache nf_nat_ipv4 nf_nat veth 8021q garp stp mrp llc pktgen lockd sunrpc]
    irq event stamp: 835637905
    hardirqs last  enabled at (835637904): __do_softirq+0x9f/0x257
    hardirqs last disabled at (835637905): apic_timer_interrupt+0x6d/0x80
    softirqs last  enabled at (5654720): __do_softirq+0x1ff/0x257
    softirqs last disabled at (5654725): irq_exit+0x5f/0xbb
    CPU 1
    Pid: 17, comm: migration/1 Tainted: G        WC   3.9.4+ #11 To be filled by O.E.M. To be filled by O.E.M./To be filled by O.E.M.
    RIP: tasklet_hi_action+0xf0/0xf0
    Process migration/1
    Call Trace:
     <IRQ>
      __do_softirq+0x117/0x257
      irq_exit+0x5f/0xbb
      smp_apic_timer_interrupt+0x8a/0x98
      apic_timer_interrupt+0x72/0x80
     <EOI>
      printk+0x4d/0x4f
      stop_machine_cpu_stop+0x22c/0x274
      cpu_stopper_thread+0xae/0x162
      smpboot_thread_fn+0x258/0x260
      kthread+0xc7/0xcf
      ret_from_fork+0x7c/0xb0

Signed-off-by: Ben Greear <greearb@candelatech.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Pekka Riikonen <priikone@iki.fi>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-06-10 17:46:57 -07:00
Linus Torvalds
1b79821fe7 zero copy error fix
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 Comment: GPGTools - http://gpgtools.org
 
 iQIcBAABAgAGBQJRtjfAAAoJEDZk62b0Tg6xEHcP/jtZbupCJBVmjvI5zBDjn4NT
 RnOoaZLz4ks1OTj2WkhkdMe7/dNh+Dlq/w9F9nw4jOZhkSN90cgDZJqK/otHqh3R
 GpXEwNS5NLysTu9qlA2Kd49C77KynafEUtFR4k0zSB/q8Uh+g8D480bps1xBeIUx
 ATlBSuYPy6SZM1PWqgllnP7IzATQtaHJSQ8uXCkfSneG+dj+13Fq9LngH7DCpKA6
 T4bU8Mx8kXlR0RcVtjjqFAf7TmOe05XG/WhgsaX5gGcpxuZ5FajCaIZeuD1rQ63K
 jLKA56VxUGa5FU6ZBZH0I+52xhdceByJdFcTW8X8fhXU6m82NYhKnMv64QZ+UjT0
 F2vNlzW7SkYvnMkjvxor/JLyi0OKIrMfElPYcuMW8pU5AVV9Hzf0M1NHLCeM2CNn
 JoghVzOPcUSistYldAJkivCcGi9sEgNadTsBrU1TM8FwkaHboUXprNf8xn2SRm1V
 iD/25/voPqbsVPtDSO9YsVEi6NldLx07yQwJy34jJ1D5Qw4MPtfPlUTLT17ikCc4
 kjY1fiov+HOcEeCse1X3IxqEB3RK/KTR6NUqOk1yY2DlLxU1ZhJfrpelOTDV9iXc
 5Ra71ebsBYb2gQqk6+do/IUxKMiLBGrt5l2KLq2ZdhWYn8Fr8O7B5gaX9BH8aOwH
 L5ROAeZxkgSJBjuKMcsi
 =+vsA
 -----END PGP SIGNATURE-----

Merge tag '9p-3.10-bug-fix-1' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs

Pull net/9p bug fix from Eric Van Hensbergen:
 "zero copy error fix"

* tag '9p-3.10-bug-fix-1' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  net/9p: Handle error in zero copy request correctly for 9p2000.u
2013-06-10 17:35:25 -07:00
Dave Airlie
e6eea1536e Merge branch 'gma500-fixes' of git://github.com/patjak/drm-gma500 into drm-fixes
Patrik writes:
Two fixes for memory leaks split into Cedarview and Poulsbo versions,
and a fix for properly setting the pipe base when using fbdev. It's on
my todo-list to start unifying the chips since they are very similar,
but until then I'd like to split them up in case there are side-effects
on Cedarview that I cannot currently test.

airled: Verified pull from github matches what I expected.
* 'gma500-fixes' of git://github.com/patjak/drm-gma500:
  drm/gma500/cdv: Fix cursor gem obj referencing on cdv
  drm/gma500/psb: Fix cursor gem obj referencing on psb
  drm/gma500/cdv: Unpin framebuffer on crtc disable
  drm/gma500/psb: Unpin framebuffer on crtc disable
  drm/gma500: Add fb gtt offset to fb base
2013-06-11 08:16:10 +10:00
Tushar Behera
589c603b2c clk: exynos5250: Add sclk_mpll to the parent list of mout_cpu clock
'mout_mpll' is added the list of parent clocks for 'mout_cpu'.
'mout_mpll' is an alias to the clock 'sclk_mpll'. Hence 'sclk_mpll'
should be added to the list of parent clocks.

This results in an error when cpufreq driver for EXYNOS5250 tries to
set 'mout_mpll' as a parent for 'mout_cpu'.

clk_set_parent: clk sclk_mpll can not be parent of clk mout_cpu

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-06-10 15:14:17 -07:00
Tushar Behera
39b72d89eb clk: exynos5250: Update cpufreq related clocks for EXYNOS5250
cpufreq driver for EXYNOS5250 is not a platform driver, hence we cannot
currently pass the clock names through a device tree node. Instead, we
need to make them available through a global alias.

cpufreq driver for EXYNOS5250 requires four clocks - 'armclk',
'mout_cpu', 'mout_mpll' and 'mout_apll'.

'armclk' has already been defined with an alias, 'mout_cpu', 'mout_mpll'
and 'mout_apll' are now defined with an alias.

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-06-10 15:14:07 -07:00
Jason Wang
92bb73ea2c tuntap: fix a possible race between queue selection and changing queues
Complier may generate codes that re-read the tun->numqueues during
tun_select_queue(). This may be a race if vlan->numqueues were changed in the
same time and can lead unexpected result (e.g. very huge value).

We need prevent the compiler from generating such codes by adding an
ACCESS_ONCE() to make sure tun->numqueues were only read once.

Bug were introduced by commit c8d68e6be1
(tuntap: multiqueue support).

Reported-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-10 14:32:47 -07:00
Jason Wang
4364d5f96e vhost_net: clear msg.control for non-zerocopy case during tx
When we decide not use zero-copy, msg.control should be set to NULL otherwise
macvtap/tap may set zerocopy callbacks which may decrease the kref of ubufs
wrongly.

Bug were introduced by commit cedb9bdce0
(vhost-net: skip head management if no outstanding).

This solves the following warnings:

WARNING: at include/linux/kref.h:47 handle_tx+0x477/0x4b0 [vhost_net]()
Modules linked in: vhost_net macvtap macvlan tun nfsd exportfs bridge stp llc openvswitch kvm_amd kvm bnx2 megaraid_sas [last unloaded: tun]
CPU: 5 PID: 8670 Comm: vhost-8668 Not tainted 3.10.0-rc2+ #1566
Hardware name: Dell Inc. PowerEdge R715/00XHKG, BIOS 1.5.2 04/19/2011
ffffffffa0198323 ffff88007c9ebd08 ffffffff81796b73 ffff88007c9ebd48
ffffffff8103d66b 000000007b773e20 ffff8800779f0000 ffff8800779f43f0
ffff8800779f8418 000000000000015c 0000000000000062 ffff88007c9ebd58
Call Trace:
[<ffffffff81796b73>] dump_stack+0x19/0x1e
[<ffffffff8103d66b>] warn_slowpath_common+0x6b/0xa0
[<ffffffff8103d6b5>] warn_slowpath_null+0x15/0x20
[<ffffffffa0197627>] handle_tx+0x477/0x4b0 [vhost_net]
[<ffffffffa0197690>] handle_tx_kick+0x10/0x20 [vhost_net]
[<ffffffffa019541e>] vhost_worker+0xfe/0x1a0 [vhost_net]
[<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
[<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
[<ffffffff81061f46>] kthread+0xc6/0xd0
[<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70
[<ffffffff817a1aec>] ret_from_fork+0x7c/0xb0
[<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70

Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-10 14:31:45 -07:00
Matthew Garrett
f8b8404337 Modify UEFI anti-bricking code
This patch reworks the UEFI anti-bricking code, including an effective
reversion of cc5a080c and 31ff2f20. It turns out that calling
QueryVariableInfo() from boot services results in some firmware
implementations jumping to physical addresses even after entering virtual
mode, so until we have 1:1 mappings for UEFI runtime space this isn't
going to work so well.

Reverting these gets us back to the situation where we'd refuse to create
variables on some systems because they classify deleted variables as "used"
until the firmware triggers a garbage collection run, which they won't do
until they reach a lower threshold. This results in it being impossible to
install a bootloader, which is unhelpful.

Feedback from Samsung indicates that the firmware doesn't need more than
5KB of storage space for its own purposes, so that seems like a reasonable
threshold. However, there's still no guarantee that a platform will attempt
garbage collection merely because it drops below this threshold. It seems
that this is often only triggered if an attempt to write generates a
genuine EFI_OUT_OF_RESOURCES error. We can force that by attempting to
create a variable larger than the remaining space. This should fail, but if
it somehow succeeds we can then immediately delete it.

I've tested this on the UEFI machines I have available, but I don't have
a Samsung and so can't verify that it avoids the bricking problem.

Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Lee, Chun-Y <jlee@suse.com> [ dummy variable cleanup ]
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-06-10 21:59:37 +01:00
Paul E. McKenney
971394f389 rcu: Fix deadlock with CPU hotplug, RCU GP init, and timer migration
In Steven Rostedt's words:

> I've been debugging the last couple of days why my tests have been
> locking up. One of my tracing tests, runs all available tracers. The
> lockup always happened with the mmiotrace, which is used to trace
> interactions between priority drivers and the kernel. But to do this
> easily, when the tracer gets registered, it disables all but the boot
> CPUs. The lockup always happened after it got done disabling the CPUs.
>
> Then I decided to try this:
>
> while :; do
> 	for i in 1 2 3; do
> 		echo 0 > /sys/devices/system/cpu/cpu$i/online
> 	done
> 	for i in 1 2 3; do
> 		echo 1 > /sys/devices/system/cpu/cpu$i/online
> 	done
> done
>
> Well, sure enough, that locked up too, with the same users. Doing a
> sysrq-w (showing all blocked tasks):
>
> [ 2991.344562]   task                        PC stack   pid father
> [ 2991.344562] rcu_preempt     D ffff88007986fdf8     0    10      2 0x00000000
> [ 2991.344562]  ffff88007986fc98 0000000000000002 ffff88007986fc48 0000000000000908
> [ 2991.344562]  ffff88007986c280 ffff88007986ffd8 ffff88007986ffd8 00000000001d3c80
> [ 2991.344562]  ffff880079248a40 ffff88007986c280 0000000000000000 00000000fffd4295
> [ 2991.344562] Call Trace:
> [ 2991.344562]  [<ffffffff815437ba>] schedule+0x64/0x66
> [ 2991.344562]  [<ffffffff81541750>] schedule_timeout+0xbc/0xf9
> [ 2991.344562]  [<ffffffff8154bec0>] ? ftrace_call+0x5/0x2f
> [ 2991.344562]  [<ffffffff81049513>] ? cascade+0xa8/0xa8
> [ 2991.344562]  [<ffffffff815417ab>] schedule_timeout_uninterruptible+0x1e/0x20
> [ 2991.344562]  [<ffffffff810c980c>] rcu_gp_kthread+0x502/0x94b
> [ 2991.344562]  [<ffffffff81062791>] ? __init_waitqueue_head+0x50/0x50
> [ 2991.344562]  [<ffffffff810c930a>] ? rcu_gp_fqs+0x64/0x64
> [ 2991.344562]  [<ffffffff81061cdb>] kthread+0xb1/0xb9
> [ 2991.344562]  [<ffffffff81091e31>] ? lock_release_holdtime.part.23+0x4e/0x55
> [ 2991.344562]  [<ffffffff81061c2a>] ? __init_kthread_worker+0x58/0x58
> [ 2991.344562]  [<ffffffff8154c1dc>] ret_from_fork+0x7c/0xb0
> [ 2991.344562]  [<ffffffff81061c2a>] ? __init_kthread_worker+0x58/0x58
> [ 2991.344562] kworker/0:1     D ffffffff81a30680     0    47      2 0x00000000
> [ 2991.344562] Workqueue: events cpuset_hotplug_workfn
> [ 2991.344562]  ffff880078dbbb58 0000000000000002 0000000000000006 00000000000000d8
> [ 2991.344562]  ffff880078db8100 ffff880078dbbfd8 ffff880078dbbfd8 00000000001d3c80
> [ 2991.344562]  ffff8800779ca5c0 ffff880078db8100 ffffffff81541fcf 0000000000000000
> [ 2991.344562] Call Trace:
> [ 2991.344562]  [<ffffffff81541fcf>] ? __mutex_lock_common+0x3d4/0x609
> [ 2991.344562]  [<ffffffff815437ba>] schedule+0x64/0x66
> [ 2991.344562]  [<ffffffff81543a39>] schedule_preempt_disabled+0x18/0x24
> [ 2991.344562]  [<ffffffff81541fcf>] __mutex_lock_common+0x3d4/0x609
> [ 2991.344562]  [<ffffffff8103d11b>] ? get_online_cpus+0x3c/0x50
> [ 2991.344562]  [<ffffffff8103d11b>] ? get_online_cpus+0x3c/0x50
> [ 2991.344562]  [<ffffffff815422ff>] mutex_lock_nested+0x3b/0x40
> [ 2991.344562]  [<ffffffff8103d11b>] get_online_cpus+0x3c/0x50
> [ 2991.344562]  [<ffffffff810af7e6>] rebuild_sched_domains_locked+0x6e/0x3a8
> [ 2991.344562]  [<ffffffff810b0ec6>] rebuild_sched_domains+0x1c/0x2a
> [ 2991.344562]  [<ffffffff810b109b>] cpuset_hotplug_workfn+0x1c7/0x1d3
> [ 2991.344562]  [<ffffffff810b0ed9>] ? cpuset_hotplug_workfn+0x5/0x1d3
> [ 2991.344562]  [<ffffffff81058e07>] process_one_work+0x2d4/0x4d1
> [ 2991.344562]  [<ffffffff81058d3a>] ? process_one_work+0x207/0x4d1
> [ 2991.344562]  [<ffffffff8105964c>] worker_thread+0x2e7/0x3b5
> [ 2991.344562]  [<ffffffff81059365>] ? rescuer_thread+0x332/0x332
> [ 2991.344562]  [<ffffffff81061cdb>] kthread+0xb1/0xb9
> [ 2991.344562]  [<ffffffff81061c2a>] ? __init_kthread_worker+0x58/0x58
> [ 2991.344562]  [<ffffffff8154c1dc>] ret_from_fork+0x7c/0xb0
> [ 2991.344562]  [<ffffffff81061c2a>] ? __init_kthread_worker+0x58/0x58
> [ 2991.344562] bash            D ffffffff81a4aa80     0  2618   2612 0x10000000
> [ 2991.344562]  ffff8800379abb58 0000000000000002 0000000000000006 0000000000000c2c
> [ 2991.344562]  ffff880077fea140 ffff8800379abfd8 ffff8800379abfd8 00000000001d3c80
> [ 2991.344562]  ffff8800779ca5c0 ffff880077fea140 ffffffff81541fcf 0000000000000000
> [ 2991.344562] Call Trace:
> [ 2991.344562]  [<ffffffff81541fcf>] ? __mutex_lock_common+0x3d4/0x609
> [ 2991.344562]  [<ffffffff815437ba>] schedule+0x64/0x66
> [ 2991.344562]  [<ffffffff81543a39>] schedule_preempt_disabled+0x18/0x24
> [ 2991.344562]  [<ffffffff81541fcf>] __mutex_lock_common+0x3d4/0x609
> [ 2991.344562]  [<ffffffff81530078>] ? rcu_cpu_notify+0x2f5/0x86e
> [ 2991.344562]  [<ffffffff81530078>] ? rcu_cpu_notify+0x2f5/0x86e
> [ 2991.344562]  [<ffffffff815422ff>] mutex_lock_nested+0x3b/0x40
> [ 2991.344562]  [<ffffffff81530078>] rcu_cpu_notify+0x2f5/0x86e
> [ 2991.344562]  [<ffffffff81091c99>] ? __lock_is_held+0x32/0x53
> [ 2991.344562]  [<ffffffff81548912>] notifier_call_chain+0x6b/0x98
> [ 2991.344562]  [<ffffffff810671fd>] __raw_notifier_call_chain+0xe/0x10
> [ 2991.344562]  [<ffffffff8103cf64>] __cpu_notify+0x20/0x32
> [ 2991.344562]  [<ffffffff8103cf8d>] cpu_notify_nofail+0x17/0x36
> [ 2991.344562]  [<ffffffff815225de>] _cpu_down+0x154/0x259
> [ 2991.344562]  [<ffffffff81522710>] cpu_down+0x2d/0x3a
> [ 2991.344562]  [<ffffffff81526351>] store_online+0x4e/0xe7
> [ 2991.344562]  [<ffffffff8134d764>] dev_attr_store+0x20/0x22
> [ 2991.344562]  [<ffffffff811b3c5f>] sysfs_write_file+0x108/0x144
> [ 2991.344562]  [<ffffffff8114c5ef>] vfs_write+0xfd/0x158
> [ 2991.344562]  [<ffffffff8114c928>] SyS_write+0x5c/0x83
> [ 2991.344562]  [<ffffffff8154c494>] tracesys+0xdd/0xe2
>
> As well as held locks:
>
> [ 3034.728033] Showing all locks held in the system:
> [ 3034.728033] 1 lock held by rcu_preempt/10:
> [ 3034.728033]  #0:  (rcu_preempt_state.onoff_mutex){+.+...}, at: [<ffffffff810c9471>] rcu_gp_kthread+0x167/0x94b
> [ 3034.728033] 4 locks held by kworker/0:1/47:
> [ 3034.728033]  #0:  (events){.+.+.+}, at: [<ffffffff81058d3a>] process_one_work+0x207/0x4d1
> [ 3034.728033]  #1:  (cpuset_hotplug_work){+.+.+.}, at: [<ffffffff81058d3a>] process_one_work+0x207/0x4d1
> [ 3034.728033]  #2:  (cpuset_mutex){+.+.+.}, at: [<ffffffff810b0ec1>] rebuild_sched_domains+0x17/0x2a
> [ 3034.728033]  #3:  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff8103d11b>] get_online_cpus+0x3c/0x50
> [ 3034.728033] 1 lock held by mingetty/2563:
> [ 3034.728033]  #0:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8131e28a>] n_tty_read+0x252/0x7e8
> [ 3034.728033] 1 lock held by mingetty/2565:
> [ 3034.728033]  #0:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8131e28a>] n_tty_read+0x252/0x7e8
> [ 3034.728033] 1 lock held by mingetty/2569:
> [ 3034.728033]  #0:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8131e28a>] n_tty_read+0x252/0x7e8
> [ 3034.728033] 1 lock held by mingetty/2572:
> [ 3034.728033]  #0:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8131e28a>] n_tty_read+0x252/0x7e8
> [ 3034.728033] 1 lock held by mingetty/2575:
> [ 3034.728033]  #0:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8131e28a>] n_tty_read+0x252/0x7e8
> [ 3034.728033] 7 locks held by bash/2618:
> [ 3034.728033]  #0:  (sb_writers#5){.+.+.+}, at: [<ffffffff8114bc3f>] file_start_write+0x2a/0x2c
> [ 3034.728033]  #1:  (&buffer->mutex#2){+.+.+.}, at: [<ffffffff811b3b93>] sysfs_write_file+0x3c/0x144
> [ 3034.728033]  #2:  (s_active#54){.+.+.+}, at: [<ffffffff811b3c3e>] sysfs_write_file+0xe7/0x144
> [ 3034.728033]  #3:  (x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff810217c2>] cpu_hotplug_driver_lock+0x17/0x19
> [ 3034.728033]  #4:  (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff8103d196>] cpu_maps_update_begin+0x17/0x19
> [ 3034.728033]  #5:  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff8103cfd8>] cpu_hotplug_begin+0x2c/0x6d
> [ 3034.728033]  #6:  (rcu_preempt_state.onoff_mutex){+.+...}, at: [<ffffffff81530078>] rcu_cpu_notify+0x2f5/0x86e
> [ 3034.728033] 1 lock held by bash/2980:
> [ 3034.728033]  #0:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8131e28a>] n_tty_read+0x252/0x7e8
>
> Things looked a little weird. Also, this is a deadlock that lockdep did
> not catch. But what we have here does not look like a circular lock
> issue:
>
> Bash is blocked in rcu_cpu_notify():
>
> 1961		/* Exclude any attempts to start a new grace period. */
> 1962		mutex_lock(&rsp->onoff_mutex);
>
>
> kworker is blocked in get_online_cpus(), which makes sense as we are
> currently taking down a CPU.
>
> But rcu_preempt is not blocked on anything. It is simply sleeping in
> rcu_gp_kthread (really rcu_gp_init) here:
>
> 1453	#ifdef CONFIG_PROVE_RCU_DELAY
> 1454			if ((prandom_u32() % (rcu_num_nodes * 8)) == 0 &&
> 1455			    system_state == SYSTEM_RUNNING)
> 1456				schedule_timeout_uninterruptible(2);
> 1457	#endif /* #ifdef CONFIG_PROVE_RCU_DELAY */
>
> And it does this while holding the onoff_mutex that bash is waiting for.
>
> Doing a function trace, it showed me where it happened:
>
> [  125.940066] rcu_pree-10      3.... 28384115273: schedule_timeout_uninterruptible <-rcu_gp_kthread
> [...]
> [  125.940066] rcu_pree-10      3d..3 28384202439: sched_switch: prev_comm=rcu_preempt prev_pid=10 prev_prio=120 prev_state=D ==> next_comm=watchdog/3 next_pid=38 next_prio=120
>
> The watchdog ran, and then:
>
> [  125.940066] watchdog-38      3d..3 28384692863: sched_switch: prev_comm=watchdog/3 prev_pid=38 prev_prio=120 prev_state=P ==> next_comm=modprobe next_pid=2848 next_prio=118
>
> Not sure what modprobe was doing, but shortly after that:
>
> [  125.940066] modprobe-2848    3d..3 28385041749: sched_switch: prev_comm=modprobe prev_pid=2848 prev_prio=118 prev_state=R+ ==> next_comm=migration/3 next_pid=40 next_prio=0
>
> Where the migration thread took down the CPU:
>
> [  125.940066] migratio-40      3d..3 28389148276: sched_switch: prev_comm=migration/3 prev_pid=40 prev_prio=0 prev_state=P ==> next_comm=swapper/3 next_pid=0 next_prio=120
>
> which finally did:
>
> [  125.940066]   <idle>-0       3...1 28389282142: arch_cpu_idle_dead <-cpu_startup_entry
> [  125.940066]   <idle>-0       3...1 28389282548: native_play_dead <-arch_cpu_idle_dead
> [  125.940066]   <idle>-0       3...1 28389282924: play_dead_common <-native_play_dead
> [  125.940066]   <idle>-0       3...1 28389283468: idle_task_exit <-play_dead_common
> [  125.940066]   <idle>-0       3...1 28389284644: amd_e400_remove_cpu <-play_dead_common
>
>
> CPU 3 is now offline, the rcu_preempt thread that ran on CPU 3 is still
> doing a schedule_timeout_uninterruptible() and it registered it's
> timeout to the timer base for CPU 3. You would think that it would get
> migrated right? The issue here is that the timer migration happens at
> the CPU notifier for CPU_DEAD. The problem is that the rcu notifier for
> CPU_DOWN is blocked waiting for the onoff_mutex to be released, which is
> held by the thread that just put itself into a uninterruptible sleep,
> that wont wake up until the CPU_DEAD notifier of the timer
> infrastructure is called, which wont happen until the rcu notifier
> finishes. Here's our deadlock!

This commit breaks this deadlock cycle by substituting a shorter udelay()
for the previous schedule_timeout_uninterruptible(), while at the same
time increasing the probability of the delay.  This maintains the intensity
of the testing.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
2013-06-10 13:37:12 -07:00
Steven Rostedt
016a8d5be6 rcu: Don't call wakeup() with rcu_node structure ->lock held
This commit fixes a lockdep-detected deadlock by moving a wake_up()
call out from a rnp->lock critical section.  Please see below for
the long version of this story.

On Tue, 2013-05-28 at 16:13 -0400, Dave Jones wrote:

> [12572.705832] ======================================================
> [12572.750317] [ INFO: possible circular locking dependency detected ]
> [12572.796978] 3.10.0-rc3+ #39 Not tainted
> [12572.833381] -------------------------------------------------------
> [12572.862233] trinity-child17/31341 is trying to acquire lock:
> [12572.870390]  (rcu_node_0){..-.-.}, at: [<ffffffff811054ff>] rcu_read_unlock_special+0x9f/0x4c0
> [12572.878859]
> but task is already holding lock:
> [12572.894894]  (&ctx->lock){-.-...}, at: [<ffffffff811390ed>] perf_lock_task_context+0x7d/0x2d0
> [12572.903381]
> which lock already depends on the new lock.
>
> [12572.927541]
> the existing dependency chain (in reverse order) is:
> [12572.943736]
> -> #4 (&ctx->lock){-.-...}:
> [12572.960032]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12572.968337]        [<ffffffff816ebc90>] _raw_spin_lock+0x40/0x80
> [12572.976633]        [<ffffffff8113c987>] __perf_event_task_sched_out+0x2e7/0x5e0
> [12572.984969]        [<ffffffff81088953>] perf_event_task_sched_out+0x93/0xa0
> [12572.993326]        [<ffffffff816ea0bf>] __schedule+0x2cf/0x9c0
> [12573.001652]        [<ffffffff816eacfe>] schedule_user+0x2e/0x70
> [12573.009998]        [<ffffffff816ecd64>] retint_careful+0x12/0x2e
> [12573.018321]
> -> #3 (&rq->lock){-.-.-.}:
> [12573.034628]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.042930]        [<ffffffff816ebc90>] _raw_spin_lock+0x40/0x80
> [12573.051248]        [<ffffffff8108e6a7>] wake_up_new_task+0xb7/0x260
> [12573.059579]        [<ffffffff810492f5>] do_fork+0x105/0x470
> [12573.067880]        [<ffffffff81049686>] kernel_thread+0x26/0x30
> [12573.076202]        [<ffffffff816cee63>] rest_init+0x23/0x140
> [12573.084508]        [<ffffffff81ed8e1f>] start_kernel+0x3f1/0x3fe
> [12573.092852]        [<ffffffff81ed856f>] x86_64_start_reservations+0x2a/0x2c
> [12573.101233]        [<ffffffff81ed863d>] x86_64_start_kernel+0xcc/0xcf
> [12573.109528]
> -> #2 (&p->pi_lock){-.-.-.}:
> [12573.125675]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.133829]        [<ffffffff816ebe9b>] _raw_spin_lock_irqsave+0x4b/0x90
> [12573.141964]        [<ffffffff8108e881>] try_to_wake_up+0x31/0x320
> [12573.150065]        [<ffffffff8108ebe2>] default_wake_function+0x12/0x20
> [12573.158151]        [<ffffffff8107bbf8>] autoremove_wake_function+0x18/0x40
> [12573.166195]        [<ffffffff81085398>] __wake_up_common+0x58/0x90
> [12573.174215]        [<ffffffff81086909>] __wake_up+0x39/0x50
> [12573.182146]        [<ffffffff810fc3da>] rcu_start_gp_advanced.isra.11+0x4a/0x50
> [12573.190119]        [<ffffffff810fdb09>] rcu_start_future_gp+0x1c9/0x1f0
> [12573.198023]        [<ffffffff810fe2c4>] rcu_nocb_kthread+0x114/0x930
> [12573.205860]        [<ffffffff8107a91d>] kthread+0xed/0x100
> [12573.213656]        [<ffffffff816f4b1c>] ret_from_fork+0x7c/0xb0
> [12573.221379]
> -> #1 (&rsp->gp_wq){..-.-.}:
> [12573.236329]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.243783]        [<ffffffff816ebe9b>] _raw_spin_lock_irqsave+0x4b/0x90
> [12573.251178]        [<ffffffff810868f3>] __wake_up+0x23/0x50
> [12573.258505]        [<ffffffff810fc3da>] rcu_start_gp_advanced.isra.11+0x4a/0x50
> [12573.265891]        [<ffffffff810fdb09>] rcu_start_future_gp+0x1c9/0x1f0
> [12573.273248]        [<ffffffff810fe2c4>] rcu_nocb_kthread+0x114/0x930
> [12573.280564]        [<ffffffff8107a91d>] kthread+0xed/0x100
> [12573.287807]        [<ffffffff816f4b1c>] ret_from_fork+0x7c/0xb0

Notice the above call chain.

rcu_start_future_gp() is called with the rnp->lock held. Then it calls
rcu_start_gp_advance, which does a wakeup.

You can't do wakeups while holding the rnp->lock, as that would mean
that you could not do a rcu_read_unlock() while holding the rq lock, or
any lock that was taken while holding the rq lock. This is because...
(See below).

> [12573.295067]
> -> #0 (rcu_node_0){..-.-.}:
> [12573.309293]        [<ffffffff810b8d36>] __lock_acquire+0x1786/0x1af0
> [12573.316568]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.323825]        [<ffffffff816ebc90>] _raw_spin_lock+0x40/0x80
> [12573.331081]        [<ffffffff811054ff>] rcu_read_unlock_special+0x9f/0x4c0
> [12573.338377]        [<ffffffff810760a6>] __rcu_read_unlock+0x96/0xa0
> [12573.345648]        [<ffffffff811391b3>] perf_lock_task_context+0x143/0x2d0
> [12573.352942]        [<ffffffff8113938e>] find_get_context+0x4e/0x1f0
> [12573.360211]        [<ffffffff811403f4>] SYSC_perf_event_open+0x514/0xbd0
> [12573.367514]        [<ffffffff81140e49>] SyS_perf_event_open+0x9/0x10
> [12573.374816]        [<ffffffff816f4dd4>] tracesys+0xdd/0xe2

Notice the above trace.

perf took its own ctx->lock, which can be taken while holding the rq
lock. While holding this lock, it did a rcu_read_unlock(). The
perf_lock_task_context() basically looks like:

rcu_read_lock();
raw_spin_lock(ctx->lock);
rcu_read_unlock();

Now, what looks to have happened, is that we scheduled after taking that
first rcu_read_lock() but before taking the spin lock. When we scheduled
back in and took the ctx->lock, the following rcu_read_unlock()
triggered the "special" code.

The rcu_read_unlock_special() takes the rnp->lock, which gives us a
possible deadlock scenario.

	CPU0		CPU1		CPU2
	----		----		----

				     rcu_nocb_kthread()
    lock(rq->lock);
		    lock(ctx->lock);
				     lock(rnp->lock);

				     wake_up();

				     lock(rq->lock);

		    rcu_read_unlock();

		    rcu_read_unlock_special();

		    lock(rnp->lock);
    lock(ctx->lock);

**** DEADLOCK ****

> [12573.382068]
> other info that might help us debug this:
>
> [12573.403229] Chain exists of:
>   rcu_node_0 --> &rq->lock --> &ctx->lock
>
> [12573.424471]  Possible unsafe locking scenario:
>
> [12573.438499]        CPU0                    CPU1
> [12573.445599]        ----                    ----
> [12573.452691]   lock(&ctx->lock);
> [12573.459799]                                lock(&rq->lock);
> [12573.467010]                                lock(&ctx->lock);
> [12573.474192]   lock(rcu_node_0);
> [12573.481262]
>  *** DEADLOCK ***
>
> [12573.501931] 1 lock held by trinity-child17/31341:
> [12573.508990]  #0:  (&ctx->lock){-.-...}, at: [<ffffffff811390ed>] perf_lock_task_context+0x7d/0x2d0
> [12573.516475]
> stack backtrace:
> [12573.530395] CPU: 1 PID: 31341 Comm: trinity-child17 Not tainted 3.10.0-rc3+ #39
> [12573.545357]  ffffffff825b4f90 ffff880219f1dbc0 ffffffff816e375b ffff880219f1dc00
> [12573.552868]  ffffffff816dfa5d ffff880219f1dc50 ffff88023ce4d1f8 ffff88023ce4ca40
> [12573.560353]  0000000000000001 0000000000000001 ffff88023ce4d1f8 ffff880219f1dcc0
> [12573.567856] Call Trace:
> [12573.575011]  [<ffffffff816e375b>] dump_stack+0x19/0x1b
> [12573.582284]  [<ffffffff816dfa5d>] print_circular_bug+0x200/0x20f
> [12573.589637]  [<ffffffff810b8d36>] __lock_acquire+0x1786/0x1af0
> [12573.596982]  [<ffffffff810918f5>] ? sched_clock_cpu+0xb5/0x100
> [12573.604344]  [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.611652]  [<ffffffff811054ff>] ? rcu_read_unlock_special+0x9f/0x4c0
> [12573.619030]  [<ffffffff816ebc90>] _raw_spin_lock+0x40/0x80
> [12573.626331]  [<ffffffff811054ff>] ? rcu_read_unlock_special+0x9f/0x4c0
> [12573.633671]  [<ffffffff811054ff>] rcu_read_unlock_special+0x9f/0x4c0
> [12573.640992]  [<ffffffff811390ed>] ? perf_lock_task_context+0x7d/0x2d0
> [12573.648330]  [<ffffffff810b429e>] ? put_lock_stats.isra.29+0xe/0x40
> [12573.655662]  [<ffffffff813095a0>] ? delay_tsc+0x90/0xe0
> [12573.662964]  [<ffffffff810760a6>] __rcu_read_unlock+0x96/0xa0
> [12573.670276]  [<ffffffff811391b3>] perf_lock_task_context+0x143/0x2d0
> [12573.677622]  [<ffffffff81139070>] ? __perf_event_enable+0x370/0x370
> [12573.684981]  [<ffffffff8113938e>] find_get_context+0x4e/0x1f0
> [12573.692358]  [<ffffffff811403f4>] SYSC_perf_event_open+0x514/0xbd0
> [12573.699753]  [<ffffffff8108cd9d>] ? get_parent_ip+0xd/0x50
> [12573.707135]  [<ffffffff810b71fd>] ? trace_hardirqs_on_caller+0xfd/0x1c0
> [12573.714599]  [<ffffffff81140e49>] SyS_perf_event_open+0x9/0x10
> [12573.721996]  [<ffffffff816f4dd4>] tracesys+0xdd/0xe2

This commit delays the wakeup via irq_work(), which is what
perf and ftrace use to perform wakeups in critical sections.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-06-10 13:37:11 -07:00
Paul E. McKenney
d62840995a trace: Allow idle-safe tracepoints to be called from irq
__DECLARE_TRACE_RCU() currently creates an _rcuidle() tracepoint which
may safely be invoked from what RCU considers to be an idle CPU.
However, these _rcuidle() tracepoints may -not- be invoked from the
handler of an irq taken from idle, because rcu_idle_enter() zeroes
RCU's nesting-level counter, so that the rcu_irq_exit() returning to
idle will trigger a WARN_ON_ONCE().

This commit therefore substitutes rcu_irq_enter() for rcu_idle_exit()
and rcu_irq_exit() for rcu_idle_enter() in order to make the _rcuidle()
tracepoints usable from irq handlers as well as from process context.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2013-06-10 13:37:10 -07:00
David S. Miller
d88210910a Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
The following patchset contains four fixes for Netfilter and one fix
for IPVS, they are:

* Fix data leak to user-space via getsockopt IP_VS_SO_GET_DESTS, from
  Dan Carpenter.

* Fix xt_TCPMSS if no TCP MSS is specified in syn packets, to avoid the
  violation of RFC879, from Phil Oester.

* Fix incomplete dump of objects via nfnetlink_acct and nfnetlink_cttimeout,
  from myself.

* Fix missing HW protocol in packets passed to user-space via NFQUEUE,
  from myself.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-10 13:30:33 -07:00
Linus Torvalds
ab0296319a spi: Fixes for v3.10
A few nasty issues, particularly a race with the interrupt controller in
 the xilinx driver, together with a couple of more minor fixes and a much
 needed move of the mailing list away from sourceforge.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIcBAABAgAGBQJRrissAAoJELSic+t+oim99qsQAJZJsEnlp/NOSt7OmPVrXv4c
 4nlqSFgqNA0wEwIjgRJgusVQsSPlTzmJpoMJrA1PDSV5lC6ilaqo1z2Nlg6w0PzL
 BGJU72vbmfCd9+rIqm5icEZPDG5CajM5fFl6cngNDUhPbOYz1Lo+DHVebkBp9won
 SNEG2UM2GL5orEvPNvy6DRrLJLBnfFAtezyC8gcL9Q4wyL2woQAaF3FaytFvL0sz
 lehIwejLQgJ9Irzz+ciqQQI+jWyII2pjSWBXb9tmoL1HAeeODrxeH/Qs1dn/s9MQ
 3ImWAOhQJCjajBzwRxuvW+I08piAr8ZaMMbVhLBUR2ZuJcjEdcJ2h5zKdU97cv2D
 hFS1JJjb1f88iOJMmcApE/NM8FVtJJjit5G6NaNGcEIi2RriTNZ6ZP8bfxvC1/sT
 wBXG3C8KTMYKHhYkM0LmBI5deQGgj5Xm1Yq/aFLiil0UCrnxIK/1cWY5UT6EWWpa
 /G6UfkE4Vt13leW/xPJtpPM9q2dsSzGFIf108t7DAVIsg2kCKFQ58yLqi4uNNnxl
 yqyhW2dCfFmas9+Oef4XdQa4e7SWQ6hCmXx1x4GncY9y/PeJqRmbpq4ROW6HwCgy
 URNvbJGoJxv+hzNlpTVI18MEq4ej1dTwJCHnMjtZir6Nt0nbjofxpCplsbRkwN4b
 eI0ubMqyFUBpTcXgYPuu
 =Lvj8
 -----END PGP SIGNATURE-----

Merge tag 'spi-v3.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi fixes from Mark Brown:
 "A few nasty issues, particularly a race with the interrupt controller
  in the xilinx driver, together with a couple of more minor fixes and a
  much needed move of the mailing list away from sourceforge."

* tag 'spi-v3.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: hspi: fixup long delay time
  spi: spi-xilinx: Remove ISR race condition
  spi: topcliff-pch: fix error return code in pch_spi_probe()
  spi: topcliff-pch: Pass correct pointer to free_irq()
  spi: Move mailing list to vger
2013-06-10 13:28:39 -07:00
Linus Torvalds
50e6f8511a Bug-fixes for regressions:
- xen/tmem stopped working after a certain combination of modprobe/swapon was used
  - cpu online/offlining would trigger WARN_ON.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.13 (GNU/Linux)
 
 iQEcBAABAgAGBQJRtgQxAAoJEFjIrFwIi8fJ9QYH/ibEGBlKLfGzN4Apx6evBA68
 l9CuLIpGCkPOiJLgVs10zY77Sg3f95bHFkJrwrEIDeTQ42joNKybsIp+qZCIS5CW
 sAnzSd6Mb8jqQYJpgLl03+z3GdFzILTJ9e0zYTETbW2vfLpAETm87XWH+gjxDK0e
 9I0kZX+Q3+2VWi5xv+UwWkYIOLbggLyKYajTHDwWNuC7vQgkJulCAbmjgN/NBv7A
 xacvXdbEClIfZ5tvJJN0RggdEWo6WyTxyExfLPmpXFbHEvWDUX5LPEf8MhFY1ORK
 U1C0BSV6YuLo350G5lY4I0R75ZEWLeUyVkZFnJIeGnUF1rP6OXEuVWTyeivPDBA=
 =Fy36
 -----END PGP SIGNATURE-----

Merge tag 'stable/for-linus-3.10-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull xen fixes from Konrad Rzeszutek Wilk:
 "Two bug-fixes for regressions:
   - xen/tmem stopped working after a certain combination of
     modprobe/swapon was used
   - cpu online/offlining would trigger WARN_ON."

* tag 'stable/for-linus-3.10-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/tmem: Don't over-write tmem_frontswap_poolid after tmem_frontswap_init set it.
  xen/smp: Fixup NOHZ per cpu data when onlining an offline CPU.
2013-06-10 13:27:46 -07:00
Linus Torvalds
30f5f73926 regmap: Fixes for v3.10
The biggest fix here is Lars-Peter's fix for custom locking callbacks
 which is pretty localised but important for those devices that use the
 feature.  Otherwise we've got a couple of fairly small cleanups which
 would have been sent sooner were it not for letting Lars-Peter's patch
 soak for a while.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIcBAABAgAGBQJRtZ9aAAoJELSic+t+oim9FKsP/09KdtRUMGIjJQFX3Lm4bEoU
 0ZQhvV6ozQWa+3faKlUeBu61yUx4R+zAgxO3rJHSEZM2+50bTZ9t70InvHOegKU7
 ipayoR/4cS23kK0uZJL9TURmoK4JuII+QVlTX/Fn9siJrrFvoSSOHjv7DxGzPZtt
 o4xgK+R8WU6zTUVIf2ncHzryaKPMs50tEt7FjPTMn+MetWsn0kgYxk3VLsORQqnL
 VJwzusJn/Z+vIy4kr9NAFGV6UljecRrIzFmn98kVHgMW1nEjr3vEE1upP2Y1TrF3
 flZqooulg7qlc2bL60/aakWXAWQ33lKZCvtMHykk46cUFN0faSbL3V9wk1N/85AN
 n6wHZKHA9APGMeImv1nL+p3DLZkhY3HYpuOgoSP8ocUpZ7y7C0wH+oGBO3nmLGjK
 4vEGPClsNFrdeF5viViIQ7ECHd9ls7t182gj3UJJjKPi27N5KppXM2ki3TQZABsS
 Q+iZ1dk/GYdyUV2E6LhoBGNnB9v6zo5pi/bABT59KuM0G6SuieRpPbchxo0VIvqY
 6cUZrzJ8Kn9VRDIc5/RIgijm9VjhbGGas/gc5nr014IKiSHMjPVXvBQ3NYw7yQw/
 SFtLgu2UBb+twQ7TWGK7BG6clHtwvSEjnvCFzPJ1q77c1gXzNfY8mCOYjfyEZ5Tb
 JuxD5znZHTvNLo+1QRQh
 =mOJz
 -----END PGP SIGNATURE-----

Merge tag 'regmap-v3.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap

Pull regmap fixes from Mark Brown:
 "The biggest fix here is Lars-Peter's fix for custom locking callbacks
  which is pretty localised but important for those devices that use the
  feature.  Otherwise we've got a couple of fairly small cleanups which
  would have been sent sooner were it not for letting Lars-Peter's patch
  soak for a while"

* tag 'regmap-v3.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: rbtree: Fixed node range check on sync
  regmap: regcache: Fixup locking for custom lock callbacks
  regmap: debugfs: Check return value of regmap_write()
2013-06-10 13:26:41 -07:00
Linus Torvalds
822b4b6fe3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 "This fixes a build problem in sahara and temporarily disables two new
  optimisations because of performance regressions until a permanent fix
  is ready"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: sahara - fix building as module
  crypto: blowfish - disable AVX2 implementation
  crypto: twofish - disable AVX2 implementation
2013-06-10 13:25:50 -07:00
Johan Hovold
2d8f4447b5 USB: pl2303: fix device initialisation at open
Do not use uninitialised termios data to determine when to configure the
device at open.

This also prevents stack data from leaking to userspace in the OOM error
path.

Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-10 11:00:49 -07:00
Johan Hovold
5e4211f1c4 USB: spcp8x5: fix device initialisation at open
Do not use uninitialised termios data to determine when to configure the
device at open.

Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-10 11:00:49 -07:00
Johan Hovold
21886725d5 USB: f81232: fix device initialisation at open
Do not use uninitialised termios data to determine when to configure the
device at open.

This also prevents stack data from leaking to userspace.

Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-10 11:00:48 -07:00
Markos Chandras
cb2f9938d0 MIPS: ftrace: Add missing CONFIG_DYNAMIC_FTRACE
arch_ftrace_update_code and ftrace_modify_all_code are only
available if CONFIG_DYNAMIC_FTRACE is selected.

Fixes the following build problem on MIPS randconfig:

arch/mips/kernel/ftrace.c: In function 'arch_ftrace_update_code':
arch/mips/kernel/ftrace.c:31:2: error: implicit declaration of function
'ftrace_modify_all_code' [-Werror=implicit-function-declaration]

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Acked-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5435/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-10 18:15:18 +02:00
Markos Chandras
d414976d1c MIPS: include: mmu_context.h: Replace VIRTUALIZATION with KVM
The kvm_* symbols are only available if KVM is selected.

Fixes the following linking problem on a randconfig:

arch/mips/built-in.o: In function `local_flush_tlb_mm':
(.text+0x18a94): undefined reference to `kvm_local_flush_tlb_all'
arch/mips/built-in.o: In function `local_flush_tlb_range':
(.text+0x18d0c): undefined reference to `kvm_local_flush_tlb_all'
kernel/built-in.o: In function `__schedule':
core.c:(.sched.text+0x2a00): undefined reference to `kvm_local_flush_tlb_all'
mm/built-in.o: In function `use_mm':
(.text+0x30214): undefined reference to `kvm_local_flush_tlb_all'
fs/built-in.o: In function `flush_old_exec':
(.text+0xf0a0): undefined reference to `kvm_local_flush_tlb_all'
make: *** [vmlinux] Error 1

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Acked-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5437/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-10 18:07:43 +02:00
Manuel Lauss
e63a24ddc7 MIPS: Alchemy: fix wait function
Only an interrupt can wake the core from 'wait', enable interrupts
locally before executing 'wait'.

[ralf@linux-mips.org: This leave the race between an interrupt that's
setting TIF_NEED_RESCHEd and entering the WAIT status. but at least it's
going to bring Alchemy back from the dead, so I'm going to apply this
patch.]

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/5408/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-10 17:59:46 +02:00
Konrad Rzeszutek Wilk
b2c75c446a xen/tmem: Don't over-write tmem_frontswap_poolid after tmem_frontswap_init set it.
Commit 10a7a07713 ("xen: tmem: enable Xen
tmem shim to be built/loaded as a module") allows the tmem module
to be loaded any time. For this work the frontswap API had to
be able to asynchronously to call tmem_frontswap_init before
or after the swap image had been set. That was added in git
commit 905cd0e1bf
("mm: frontswap: lazy initialization to allow tmem backends to build/run as modules").

Which means we could do this (The common case):

 modprobe tmem		[so calls frontswap_register_ops, no ->init]
			 modifies tmem_frontswap_poolid = -1
 swapon /dev/xvda1	[__frontswap_init, calls -> init, tmem_frontswap_poolid is
			 < 0 so tmem hypercall done]

Or the failing one:

 swapon /dev/xvda1	[calls __frontswap_init, sets the need_init bitmap]
 modprobe tmem		[calls frontswap_register_ops, -->init calls, finds out
			tmem_frontswap_poolid is 0, does not make a hypercall.
			Later in the module_init, sets tmem_frontswap_poolid=-1]

Which meant that in the failing case we would not call the hypercall
to initialize the pool and never be able to make any frontswap
backend calls.

Moving the frontswap_register_ops after setting the tmem_frontswap_poolid
fixes it.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
2013-06-10 10:14:33 -04:00
Ben Hutchings
c46b54f740 s390/pci: Implement IRQ functions if !PCI
All architectures must implement IRQ functions.  Since various
dependencies on !S390 were removed, there are various drivers that can
be selected but will fail to link.  Provide a dummy implementation of
these functions for the !PCI case.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: stable@vger.kernel.org # 3.9
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-06-10 16:06:04 +02:00
Dan Carpenter
a8241c6351 ipvs: info leak in __ip_vs_get_dest_entries()
The entry struct has a 2 byte hole after ->port and another 4 byte
hole after ->stats.outpkts.  You must have CAP_NET_ADMIN in your
namespace to hit this information leak.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-06-10 14:53:00 +02:00
Rafael J. Wysocki
8c9b7a7b2f ACPI / video: Do not bind to device objects with a scan handler
With the introduction of ACPI scan handlers, ACPI device objects
with an ACPI scan handler attached to them must not be bound to
by ACPI drivers any more.  Unfortunately, however, the ACPI video
driver attempts to do just that if there is a _ROM ACPI control
method defined under a device object with an ACPI scan handler.

Prevent that from happening by making the video driver's "add"
routine check if the device object already has an ACPI scan handler
attached to it and return an error code in that case.

That is not sufficient, though, because acpi_bus_driver_init() would
then clear the device object's driver_data that may be set by its
scan handler, so for the fix to work acpi_bus_driver_init() has to be
modified to leave driver_data as is on errors.

References: https://bugzilla.kernel.org/show_bug.cgi?id=58091
Bisected-and-tested-by: Dmitry S. Demin <dmitryy.demin@gmail.com>
Reported-and-tested-by: Jason Cassell <bluesloth600@gmail.com>
Tracked-down-by: Aaron Lu <aaron.lu@intel.com>
Cc: 3.9+ <stable@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
2013-06-10 13:00:29 +02:00
Mark Brown
902a75cdc4 Merge remote-tracking branch 'asoc/fix/wm8994' into asoc-linus 2013-06-10 10:28:51 +01:00
Mark Brown
4351ac5b9f Merge remote-tracking branch 'asoc/fix/tlv320aic3x' into asoc-linus 2013-06-10 10:28:50 +01:00
Mark Brown
97a47ce9d2 Merge remote-tracking branch 'asoc/fix/maintainers' into asoc-linus 2013-06-10 10:28:50 +01:00
Mark Brown
ed75019204 Merge remote-tracking branch 'asoc/fix/cs42l52' into asoc-linus 2013-06-10 10:28:49 +01:00
Mark Brown
56f1275b85 Merge remote-tracking branch 'asoc/fix/core' into asoc-linus 2013-06-10 10:28:49 +01:00
Mark Brown
97e0002aab Merge remote-tracking branch 'asoc/fix/arizona' into asoc-linus 2013-06-10 10:28:48 +01:00
Daniel Vetter
c3456fb3e4 drm/i915: prefer VBT modes for SVDO-LVDS over EDID
In

commit 53d3b4d777
Author: Egbert Eich <eich@suse.de>
Date:   Tue Jun 4 17:13:21 2013 +0200

    drm/i915/sdvo: Use &intel_sdvo->ddc instead of intel_sdvo->i2c for DDC

Egbert Eich fixed a long-standing bug where we simply used a
non-working i2c controller to read the EDID for SDVO-LVDS panels.
Unfortunately some machines seem to not be able to cope with the mode
provided in the EDID. Specifically they seem to not be able to cope
with a 4x pixel mutliplier instead of a 2x one, which seems to have
been worked around by slightly changing the panels native mode in the
VBT so that the dotclock is just barely above 50MHz.

Since it took forever to notice the breakage it's fairly safe to
assume that at least for SDVO-LVDS panels the VBT contains fairly sane
data. So just switch around the order and use VBT modes first.

v2: Also add EDID modes just in case, and spell Egbert correctly.

v3: Elaborate a bit more about what's going on on Chris' machine.

Cc: Egbert Eich <eich@suse.de>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=65524
Cc: stable@vger.kernel.org
Reported-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-06-10 10:13:34 +02:00
Chris Wilson
7ba220cec0 drm/i915: Enable hotplug interrupts after querying hw capabilities.
sdvo->hotplug_active is initialised during intel_sdvo_setup_outputs(),
and so we never enabled the hotplug interrupts on SDVO as we were
checking too early.

This regression has been introduced somewhere in the hpd rework for
the storm detection and handling starting with

commit 1d843f9de4
Author: Egbert Eich <eich@suse.de>
Date:   Mon Feb 25 12:06:49 2013 -0500

    DRM/I915: Add enum hpd_pin to intel_encoder.

and the follow-up patches to use the new encoder->hpd_pin variable for
the different irq setup functions.

The problem is that encoder->hpd_pin was set up _before_ the output
setup was done and so before we could assess the hotplug capabilities
of the outputs on an sdvo encoder.

Reported-by: Alex Fiestas <afiestas@kde.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=58405
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Add regression note.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-06-10 09:59:26 +02:00
Chris Wilson
7ee2aff373 drm/i915: Fix hotplug interrupt enabling for SDVOC
A broken conditional would lead to SDVOC waiting upon hotplug events on
SDVOB - and so miss all activity on its SDVO port.

This regression has been introduced in

commit 1d843f9de4
Author: Egbert Eich <eich@suse.de>
Date:   Mon Feb 25 12:06:49 2013 -0500

    DRM/I915: Add enum hpd_pin to intel_encoder.

References: https://bugs.freedesktop.org/show_bug.cgi?id=58405
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Add regression note.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-06-10 09:58:18 +02:00
Simon Wunderlich
d5b4c93e67 batman-adv: Don't handle address updates when bla is disabled
The bridge loop avoidance has a hook to handle address updates of the
originator. These should not be handled when bridge loop avoidance is
disabled - it might send some bridge loop avoidance packets which should
not appear if bla is disabled.

Signed-off-by: Simon Wunderlich <simon@open-mesh.com>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2013-06-10 08:42:18 +02:00
Simon Wunderlich
7c24bbbeab batman-adv: forward late OGMs from best next hop
When a packet is received from another node first and later from the
best next hop, this packet is dropped. However the first OGM was sent
with the BATADV_NOT_BEST_NEXT_HOP flag and thus dropped by neighbors.
The late OGM from the best neighbor is then dropped because it is a
duplicate.

If this situation happens constantly, a node might end up not forwarding
the "valid" OGMs anymore, and nodes behind will starve from not getting
valid OGMs.

Fix this by refining the duplicate checking behaviour: The actions
should depend on whether it was a duplicate for a neighbor only or for
the originator. OGMs which are not duplicates for a specific neighbor
will now be considered in batadv_iv_ogm_forward(), but only actually
forwarded for the best next hop. Therefore, late OGMs from the best
next hop are forwarded now and not dropped as duplicates anymore.

Signed-off-by: Simon Wunderlich <simon@open-mesh.com>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2013-06-10 08:42:17 +02:00
Matthias Schiffer
ac16d1484e batman-adv: wait for rtnl in batadv_store_mesh_iface instead of failing if it is taken
The rtnl_lock in batadv_store_mesh_iface has been converted to a rtnl_trylock
some time ago to avoid a possible deadlock between rtnl and s_active on removal
of the sysfs nodes.

The behaviour introduced by that was quite confusing as it could lead to the
sysfs store to fail, making batman-adv setup scripts unreliable. As recently the
sysfs removal was postponed to a worker not running with the rtnl taken, the
deadlock can't occur any more and it is safe to change the trylock back to a
lock to make the sysfs store reliable again.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Reviewed-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2013-06-10 08:42:16 +02:00
Linus Torvalds
ae75d84f3e Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc fixes from Benjamin Herrenschmidt:
 "This is purely regressions (though not all recent ones) or stable
  material"

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Partial revert of "Context switch more PMU related SPRs"
  powerpc/perf: Fix deadlock caused by calling printk() in PMU exception
  powerpc/hw_breakpoints: Add DABRX cpu feature to fix 32-bit regression
  powerpc/power8: Update denormalization handler
  powerpc/pseries: Simplify denormalization handler
  powerpc/power8: Fix oprofile and perf
  powerpc/eeh: Don't check RTAS token to get PE addr
  powerpc/pci: Check the bus address instead of resource address in pcibios_fixup_resources
2013-06-09 18:01:45 -07:00