Commit Graph

17451 Commits

Author SHA1 Message Date
Paul E. McKenney
96d3fd0d31 rcu: Break call_rcu() deadlock involving scheduler and perf
Dave Jones got the following lockdep splat:

>  ======================================================
>  [ INFO: possible circular locking dependency detected ]
>  3.12.0-rc3+ #92 Not tainted
>  -------------------------------------------------------
>  trinity-child2/15191 is trying to acquire lock:
>   (&rdp->nocb_wq){......}, at: [<ffffffff8108ff43>] __wake_up+0x23/0x50
>
> but task is already holding lock:
>   (&ctx->lock){-.-...}, at: [<ffffffff81154c19>] perf_event_exit_task+0x109/0x230
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #3 (&ctx->lock){-.-...}:
>         [<ffffffff810cc243>] lock_acquire+0x93/0x200
>         [<ffffffff81733f90>] _raw_spin_lock+0x40/0x80
>         [<ffffffff811500ff>] __perf_event_task_sched_out+0x2df/0x5e0
>         [<ffffffff81091b83>] perf_event_task_sched_out+0x93/0xa0
>         [<ffffffff81732052>] __schedule+0x1d2/0xa20
>         [<ffffffff81732f30>] preempt_schedule_irq+0x50/0xb0
>         [<ffffffff817352b6>] retint_kernel+0x26/0x30
>         [<ffffffff813eed04>] tty_flip_buffer_push+0x34/0x50
>         [<ffffffff813f0504>] pty_write+0x54/0x60
>         [<ffffffff813e900d>] n_tty_write+0x32d/0x4e0
>         [<ffffffff813e5838>] tty_write+0x158/0x2d0
>         [<ffffffff811c4850>] vfs_write+0xc0/0x1f0
>         [<ffffffff811c52cc>] SyS_write+0x4c/0xa0
>         [<ffffffff8173d4e4>] tracesys+0xdd/0xe2
>
> -> #2 (&rq->lock){-.-.-.}:
>         [<ffffffff810cc243>] lock_acquire+0x93/0x200
>         [<ffffffff81733f90>] _raw_spin_lock+0x40/0x80
>         [<ffffffff810980b2>] wake_up_new_task+0xc2/0x2e0
>         [<ffffffff81054336>] do_fork+0x126/0x460
>         [<ffffffff81054696>] kernel_thread+0x26/0x30
>         [<ffffffff8171ff93>] rest_init+0x23/0x140
>         [<ffffffff81ee1e4b>] start_kernel+0x3f6/0x403
>         [<ffffffff81ee1571>] x86_64_start_reservations+0x2a/0x2c
>         [<ffffffff81ee1664>] x86_64_start_kernel+0xf1/0xf4
>
> -> #1 (&p->pi_lock){-.-.-.}:
>         [<ffffffff810cc243>] lock_acquire+0x93/0x200
>         [<ffffffff8173419b>] _raw_spin_lock_irqsave+0x4b/0x90
>         [<ffffffff810979d1>] try_to_wake_up+0x31/0x350
>         [<ffffffff81097d62>] default_wake_function+0x12/0x20
>         [<ffffffff81084af8>] autoremove_wake_function+0x18/0x40
>         [<ffffffff8108ea38>] __wake_up_common+0x58/0x90
>         [<ffffffff8108ff59>] __wake_up+0x39/0x50
>         [<ffffffff8110d4f8>] __call_rcu_nocb_enqueue+0xa8/0xc0
>         [<ffffffff81111450>] __call_rcu+0x140/0x820
>         [<ffffffff81111b8d>] call_rcu+0x1d/0x20
>         [<ffffffff81093697>] cpu_attach_domain+0x287/0x360
>         [<ffffffff81099d7e>] build_sched_domains+0xe5e/0x10a0
>         [<ffffffff81efa7fc>] sched_init_smp+0x3b7/0x47a
>         [<ffffffff81ee1f4e>] kernel_init_freeable+0xf6/0x202
>         [<ffffffff817200be>] kernel_init+0xe/0x190
>         [<ffffffff8173d22c>] ret_from_fork+0x7c/0xb0
>
> -> #0 (&rdp->nocb_wq){......}:
>         [<ffffffff810cb7ca>] __lock_acquire+0x191a/0x1be0
>         [<ffffffff810cc243>] lock_acquire+0x93/0x200
>         [<ffffffff8173419b>] _raw_spin_lock_irqsave+0x4b/0x90
>         [<ffffffff8108ff43>] __wake_up+0x23/0x50
>         [<ffffffff8110d4f8>] __call_rcu_nocb_enqueue+0xa8/0xc0
>         [<ffffffff81111450>] __call_rcu+0x140/0x820
>         [<ffffffff81111bb0>] kfree_call_rcu+0x20/0x30
>         [<ffffffff81149abf>] put_ctx+0x4f/0x70
>         [<ffffffff81154c3e>] perf_event_exit_task+0x12e/0x230
>         [<ffffffff81056b8d>] do_exit+0x30d/0xcc0
>         [<ffffffff8105893c>] do_group_exit+0x4c/0xc0
>         [<ffffffff810589c4>] SyS_exit_group+0x14/0x20
>         [<ffffffff8173d4e4>] tracesys+0xdd/0xe2
>
> other info that might help us debug this:
>
> Chain exists of:
>   &rdp->nocb_wq --> &rq->lock --> &ctx->lock
>
>   Possible unsafe locking scenario:
>
>         CPU0                    CPU1
>         ----                    ----
>    lock(&ctx->lock);
>                                 lock(&rq->lock);
>                                 lock(&ctx->lock);
>    lock(&rdp->nocb_wq);
>
>  *** DEADLOCK ***
>
> 1 lock held by trinity-child2/15191:
>  #0:  (&ctx->lock){-.-...}, at: [<ffffffff81154c19>] perf_event_exit_task+0x109/0x230
>
> stack backtrace:
> CPU: 2 PID: 15191 Comm: trinity-child2 Not tainted 3.12.0-rc3+ #92
>  ffffffff82565b70 ffff880070c2dbf8 ffffffff8172a363 ffffffff824edf40
>  ffff880070c2dc38 ffffffff81726741 ffff880070c2dc90 ffff88022383b1c0
>  ffff88022383aac0 0000000000000000 ffff88022383b188 ffff88022383b1c0
> Call Trace:
>  [<ffffffff8172a363>] dump_stack+0x4e/0x82
>  [<ffffffff81726741>] print_circular_bug+0x200/0x20f
>  [<ffffffff810cb7ca>] __lock_acquire+0x191a/0x1be0
>  [<ffffffff810c6439>] ? get_lock_stats+0x19/0x60
>  [<ffffffff8100b2f4>] ? native_sched_clock+0x24/0x80
>  [<ffffffff810cc243>] lock_acquire+0x93/0x200
>  [<ffffffff8108ff43>] ? __wake_up+0x23/0x50
>  [<ffffffff8173419b>] _raw_spin_lock_irqsave+0x4b/0x90
>  [<ffffffff8108ff43>] ? __wake_up+0x23/0x50
>  [<ffffffff8108ff43>] __wake_up+0x23/0x50
>  [<ffffffff8110d4f8>] __call_rcu_nocb_enqueue+0xa8/0xc0
>  [<ffffffff81111450>] __call_rcu+0x140/0x820
>  [<ffffffff8109bc8f>] ? local_clock+0x3f/0x50
>  [<ffffffff81111bb0>] kfree_call_rcu+0x20/0x30
>  [<ffffffff81149abf>] put_ctx+0x4f/0x70
>  [<ffffffff81154c3e>] perf_event_exit_task+0x12e/0x230
>  [<ffffffff81056b8d>] do_exit+0x30d/0xcc0
>  [<ffffffff810c9af5>] ? trace_hardirqs_on_caller+0x115/0x1e0
>  [<ffffffff810c9bcd>] ? trace_hardirqs_on+0xd/0x10
>  [<ffffffff8105893c>] do_group_exit+0x4c/0xc0
>  [<ffffffff810589c4>] SyS_exit_group+0x14/0x20
>  [<ffffffff8173d4e4>] tracesys+0xdd/0xe2

The underlying problem is that perf is invoking call_rcu() with the
scheduler locks held, but in NOCB mode, call_rcu() will with high
probability invoke the scheduler -- which just might want to use its
locks.  The reason that call_rcu() needs to invoke the scheduler is
to wake up the corresponding rcuo callback-offload kthread, which
does the job of starting up a grace period and invoking the callbacks
afterwards.

One solution (championed on a related problem by Lai Jiangshan) is to
simply defer the wakeup to some point where scheduler locks are no longer
held.  Since we don't want to unnecessarily incur the cost of such
deferral, the task before us is threefold:

1.	Determine when it is likely that a relevant scheduler lock is held.

2.	Defer the wakeup in such cases.

3.	Ensure that all deferred wakeups eventually happen, preferably
	sooner rather than later.

We use irqs_disabled_flags() as a proxy for relevant scheduler locks
being held.  This works because the relevant locks are always acquired
with interrupts disabled.  We may defer more often than needed, but that
is at least safe.

The wakeup deferral is tracked via a new field in the per-CPU and
per-RCU-flavor rcu_data structure, namely ->nocb_defer_wakeup.

This flag is checked by the RCU core processing.  The __rcu_pending()
function now checks this flag, which causes rcu_check_callbacks()
to initiate RCU core processing at each scheduling-clock interrupt
where this flag is set.  Of course this is not sufficient because
scheduling-clock interrupts are often turned off (the things we used to
be able to count on!).  So the flags are also checked on entry to any
state that RCU considers to be idle, which includes both NO_HZ_IDLE idle
state and NO_HZ_FULL user-mode-execution state.

This approach should allow call_rcu() to be invoked regardless of what
locks you might be holding, the key word being "should".

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
2013-12-03 10:10:18 -08:00
Paul E. McKenney
6c43c091bd documentation: Update circular buffer for load-acquire/store-release
This commit replaces full barriers by targeted use of load-acquire and
store-release.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Restore comments as suggested by David Howells. ]
2013-12-03 10:08:57 -08:00
Paul E. McKenney
9873552fc1 documentation: Fix circular-buffer example.
The code sample in Documentation/circular-buffers.txt appears to have a
few ordering bugs.  This patch therefore applies the needed fixes.

Reported-by: Lech Fomicki <lfomicki@poczta.fm>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-12-03 10:08:56 -08:00
Paul E. McKenney
97e63f0caf rcu: Fix formatting blows in kernel-parameters.txt
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-12-03 10:08:56 -08:00
Paul E. McKenney
c9592ecb98 rcu: Fix typo in Documentation/RCU/trace.txt
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-12-03 10:08:56 -08:00
Stephen Warren
831eae69a8 staging: dwc2: set up all module params
The DWC2 USB controller in the BCM2835 (Raspberry Pi) needs some non-
default parameters. Select these based on the compatible value from the
DT node. For all other HW, fall back to the default parameters currently
in use.

The values in params_bcm2835[] were posted to the mailing list by Paul
quite some time ago. I made a couple of minor modifications since then;
to set ahbcfg instead of ahb_single, and to set uframe_sched.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-03 09:01:45 -08:00
Alexandre Courbot
56a39aac59 Documentation: gpiolib: add 00-INDEX file
Give a short overview of the various GPIO documentation files.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-03 13:10:48 +01:00
Jonas Jensen
0299b77b44 gpio: Add MOXA ART GPIO driver
Add GPIO driver for MOXA ART SoCs.

Signed-off-by: Jonas Jensen <jonas.jensen@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-03 11:26:08 +01:00
Laurent Pinchart
6125752556 gpio: rcar: Add r8a7791 support to the DT bindings
The r8a7791 (R-Car M2) has a GPIO controller with additional features
compared to the generic renesas,gpio-rcar compatible devices. Add a
model-specific string to let the driver enable these features.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-03 11:26:08 +01:00
Gerhard Sittig
2c0e641a96 dt: binding: reword PowerPC 8xxx GPIO documentation
re-format and re-word the device tree binding documentation for MPC8xxx
and compatibles, reference the common document for interrupt controllers
and remove outdated duplicate SoC specific information

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <Pawel.Moll@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: <devicetree@vger.kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-12-03 00:01:03 -06:00
Stephen Warren
72d944ec7e ARM: tegra: delete nvidia,tegra20-spi.txt binding
This binding shouldn't exist; Tegra20 has two forms of SPI controller
that are documented separately in nvidia,tegra20-sflash.txt and
nvidia,tegra20-slink.txt.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-12-03 00:00:33 -06:00
Chanwoo Choi
1675088f8b hwmon: ntc_thermistor: Fix typo (pullup-uV -> pullup-uv)
This patch fix typo of property name from 'pullup-uV' to 'pullup-uv'.
The ntc_thermistor.c use 'pullup-uv' when parsing dt data.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-12-02 23:40:42 -06:00
Wei Ni
dd622d2506 of: add vendor prefix for GMT
Adding Global Mixed-mode Technology Inc. to the list
of devicetree vendor prefixes.

Signed-off-by: Wei Ni <wni@nvidia.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-12-02 23:37:23 -06:00
Laurent Pinchart
cdbea09819 clk: exynos: Fix typos in DT bindings documentation
s/comptible/compatible/

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-12-02 23:36:50 -06:00
Thierry Reding
53d6b36020 of: Add vendor prefix for LG Corporation
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-12-02 23:35:44 -06:00
Fabio Estevam
21ea026861 Documentation: net: fsl-fec.txt: Add phy-supply entry
phy-supply is an optional property of the fec driver, so add it to the binding
documentation.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-12-02 23:35:35 -06:00
Sricharan R
f1e8e38114 ARM: dts: doc: Document missing binding for omap5-mpu
The binding and support for omap5-mpu which has a cortex-a15
smp core, gic and integrated L2 cache has been existing for sometime.
So Documenting the missing binding here.

Cc: Benoit Cousson <bcousson@baylibre.com>
Signed-off-by: Sricharan R <r.sricharan@ti.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-12-02 23:35:23 -06:00
Rob Herring
f04bda9039 dt-bindings: add ARMv8 PMU binding
Add missing "arm,armv8-pmuv3" compatible property for ARMv8 PMU.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
2013-12-02 23:21:02 -06:00
Greg Kroah-Hartman
06749f192b Merge v3.13-rc2 into staging-next
we want these fixes in here.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-02 16:39:07 -08:00
Valentine Barshak
80361fa02e libata, dt: Document sata_rcar bindings
These bindings can be used to register SATA devices found on R-Car SoC.

Signed-off-by: Valentine Barshak <valentine.barshak@cogentembedded.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2013-12-02 14:53:51 -05:00
John W. Linville
4b074b0762 Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next 2013-12-02 14:25:38 -05:00
Boris BREZILLON
32f955c6da dt: binding: add at91 clks dt bindings documentation
This patch adds new at91 clks dt bindings documentation.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2013-12-02 15:31:26 +01:00
Qiang Huang
ca0bdbb5fd cgroup, doc: make cgroup_disable doc more accurate
In doc, it said that 'Currently supported controllers - "memory"',
but actually we can use cgroup_disable=cpu,cpuset and all other
controllers, so this is confusing for cgroup users without much
cgroup knowledge. We need to make it clear.

[some comments copied from Paul Menage's original patch 8bab8dded]

Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-02 14:50:46 +01:00
ZHAO Gang
ac6d662a95 doc: Add "*.svg" to DocBook/.gitignore
Mauro add "*.png" and "*.gif" in DocBook/.gitignore in commit 6d172492,
but forgot to add "*.svg", this made git unnecessary to track directory
DocBook/media_api generated by `make htmldocs`:

 $ git status
 # On branch master
 # Untracked files:
 #   (use "git add <file>..." to include in what will be committed)
 #
 #	Documentation/DocBook/media_api/
 nothing added to commit but untracked files present (use "git add" to track)

Add "*.svg" to DocBook/.gitignore so git will not track directory
DocBook/media_api, since there is no file in that directory it interest in.

Signed-off-by: ZHAO Gang <gamerh2o@gmail.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-02 14:49:19 +01:00
Xishi Qiu
d9a6ed1fa4 doc: fix some typos
Fix some typos in three documentations.

Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-02 14:48:28 +01:00
Richard Weinberger
ff18dd8f1c Documentation: Update x86_64/boot-options.txt
Removed obsolte parameters from boot-options.txt.
Verified by grepping around in arch/x86/.

Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-02 14:47:44 +01:00
Stefan Raspl
0899d6ac46 documentation: Add links to TRACE_EVENT documentation
documentation: Add links to TRACE_EVENT documentation

Existing tracepoint documentation doesn't mention the popular
TRACE_EVENT
macro. Since an excellent series of articles on proper usage already
exists, respective links are added to the existing documentation.

Signed-off-by: Stefan Raspl <raspl@linux.vnet.ibm.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-02 14:47:05 +01:00
Ben Hutchings
832919bfcf DocBook: Make mandocs parallel-safe
Two concurrent calls to cmd_db2man may attempt to compress manual
pages generated by each other.  gzip can then fail due to an input
file having already been compressed and removed.

Move the gzip command to the top-level mandocs target.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Bastian Blank <waldi@debian.org>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-02 14:46:37 +01:00
Robert P. J. Day
c4d79a4799 work around xmlto bug in htmldocs
Trying to generate xhtml causes all functions to show up with a prefix
of "fsfunc" in the output, so just back off to html until someone
fixes the toolchain.

Note that this is not a problem with kernel-doc, it's an issue with
however "xmlto" renders xhtml output.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-02 14:45:58 +01:00
Xishi Qiu
c79a8d85d7 doc: fix some typos in documentations
Fix some typos in five documentations, no functional change.

Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-02 14:45:19 +01:00
Robert P. J. Day
0666029435 DocBook: include !Emm/util.c in kernel-api to include, kzfree and more
Add the exported symbols from mm/util.c to the kernel-api memory
management section, to pick up obvious routines like kzfree and
krealloc.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-02 14:42:57 +01:00
Kuninori Morimoto
fa558c2801 ASoC: simple-card: add Device Tree support
Support for loading the simple-card module via DeviceTree.
It requests CPU/CODEC information.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-12-02 12:37:28 +00:00
David Howells
23fd78d764 KEYS: Fix multiple key add into associative array
If sufficient keys (or keyrings) are added into a keyring such that a node in
the associative array's tree overflows (each node has a capacity N, currently
16) and such that all N+1 keys have the same index key segment for that level
of the tree (the level'th nibble of the index key), then assoc_array_insert()
calls ops->diff_objects() to indicate at which bit position the two index keys
vary.

However, __key_link_begin() passes a NULL object to assoc_array_insert() with
the intention of supplying the correct pointer later before we commit the
change.  This means that keyring_diff_objects() is given a NULL pointer as one
of its arguments which it does not expect.  This results in an oops like the
attached.

With the previous patch to fix the keyring hash function, this can be forced
much more easily by creating a keyring and only adding keyrings to it.  Add any
other sort of key and a different insertion path is taken - all 16+1 objects
must want to cluster in the same node slot.

This can be tested by:

	r=`keyctl newring sandbox @s`
	for ((i=0; i<=16; i++)); do keyctl newring ring$i $r; done

This should work fine, but oopses when the 17th keyring is added.

Since ops->diff_objects() is always called with the first pointer pointing to
the object to be inserted (ie. the NULL pointer), we can fix the problem by
changing the to-be-inserted object pointer to point to the index key passed
into assoc_array_insert() instead.

Whilst we're at it, we also switch the arguments so that they are the same as
for ->compare_object().

BUG: unable to handle kernel NULL pointer dereference at 0000000000000088
IP: [<ffffffff81191ee4>] hash_key_type_and_desc+0x18/0xb0
...
RIP: 0010:[<ffffffff81191ee4>] hash_key_type_and_desc+0x18/0xb0
...
Call Trace:
 [<ffffffff81191f9d>] keyring_diff_objects+0x21/0xd2
 [<ffffffff811f09ef>] assoc_array_insert+0x3b6/0x908
 [<ffffffff811929a7>] __key_link_begin+0x78/0xe5
 [<ffffffff81191a2e>] key_create_or_update+0x17d/0x36a
 [<ffffffff81192e0a>] SyS_add_key+0x123/0x183
 [<ffffffff81400ddb>] tracesys+0xdd/0xe2

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Stephen Gallagher <sgallagh@redhat.com>
2013-12-02 11:24:18 +00:00
Henrik Austad
854ff82ab0 Documentation/robust-futex-API: Count properly to 4
A strictly monotonically increasing sequence is normally used in
numbered lists as they provide an intuitive ordering of the
elements.

However, in situations where race conditions can appear, this
assumption breaks down and you can end up with unpredictable
results, leading to a rather confusing list :-)

This changes the numbered list 1,2,2,2 to the more intuitive
1,2,3,4.

Introduced in:

  2eec9ad91f [PATCH] lightweight robust futexes: docs

Signed-off-by: Henrik Austad <henrik@austad.us>
Link: http://lkml.kernel.org/r/1385590680-8110-1-git-send-email-henrik@austad.us
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-30 14:08:28 +01:00
Philipp Zabel
ea3aba8482 [media] videobuf2: Add support for file access mode flags for DMABUF exporting
Currently it is not possible for userspace to map a DMABUF exported buffer
with write permissions. This patch allows to also pass O_RDONLY/O_RDWR when
exporting the buffer, so that userspace may map it with write permissions.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-11-29 14:12:43 -02:00
Linus Torvalds
dda9cc3a14 Merge tag 'gpio-v3.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO fixes from Linus Walleij:
 "Here us a bunch of patches for the v3.13 series.  Most important stuff
  is related to fixes and documentation for the new GPIO descriptor API.
  If the diffstat is scary you'll notice most of it is to
  Documentation/*:

   - A big slew of documentation for the gpiod transition that happened
     in the merge window, no semantic effect, but we should provide
     proper documentation with the new API.

   - Fix flags related to the new API.

   - Fix to the find_chip_by_name() lookup function related to the new
     API.

   - Fix of_find_gpio() when not using device tree.

   - Bug fix for the TB10x direction setting.

   - Error path fixes from Dan Carpenter.

   - Nasty IRQdomain bug relating to taking an unitialized spinlock.

   - Minor fixes here and there"

* tag 'gpio-v3.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: bcm281xx: Fix return value of bcm_kona_gpio_get()
  gpio: pl061: move irqdomain initialization
  gpio: ucb1400: Add MODULE_ALIAS
  gpiolib: fix of_find_gpio() when OF not defined
  gpio: fix memory leak in error path
  gpio: rcar: NULL dereference on error in probe()
  gpio: msm: make msm_gpio.summary_irq signed for error handling
  gpio: mvebu: make mvchip->irqbase signed for error handling
  gpiolib: use dedicated flags for GPIO properties
  gpiolib: fix find_chip_by_name()
  Documentation: gpiolib: document new interface
  gpio: tb10x: Set output value before setting direction to output
2013-11-28 09:57:46 -08:00
Brian Austin
3a85ca9d8a ASoC: dt: binding: sound cs42l52 driver
Signed-off-by: Brian Austin <brian.austin@cirrus.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-11-28 10:57:01 +00:00
Nicolas Dichtel
96d5d9d9e8 doc: fix generation of device-drivers
Since commit 7a6354e241 ("sched: Move wait.c into kernel/sched/"), the
path of this file has changed.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Andy Whitcroft <apw@canonical.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-27 20:40:04 -08:00
Dave Jones
dad337501d remove obsolete references to powertweak
This tool hasn't been maintained in over a decade, and is pretty much
useless these days.  Let's pretend it never happened.

Also remove a long-dead email address.

Signed-off-by: Dave Jones <davej@fedoraproject.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-27 20:34:32 -08:00
Ezequiel Garcia
f881591dd4 clk: fixed-factor: Fix device-tree binding typo
The required properties are not named "div" and "mult",
but rather "clock-div" and "clock-mult".

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-11-27 12:48:41 -08:00
Ashutosh Dixit
173c072787 misc: mic: Fix endianness issues.
Endianness issues are now consistent as per the documentation in
host/mic_virtio.h. Sparse warnings related to endianness are also fixed.
Note that the MIC driver implementation assumes that the host can be
both BE or LE whereas the card is always LE.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Sudeep Dutt <sudeep.dutt@intel.com>
Reviewed-by: Nikhil Rao <nikhil.rao@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-27 11:03:38 -08:00
Ashutosh Dixit
1e31aa9270 misc: mic: Fix user space namespace pollution from mic_common.h.
Avoid declaring ALIGN() and __aligned() in
include/uapi/linux/mic_common.h since they pollute user space
namespace. Also, mic_aligned_size() can be simply replaced simply by
sizeof() since all structures where mic_aligned_size() is used are
declared using __attribute__ ((aligned(8)));

--
>From mail from H Peter Anvin about this:

On Fri, Nov 08, 2013 H Peter Anvin <h.peter.anvin@intel.com> wrote:
Subject: Namespace pollution in mic_common.h

This puts two macros, ALIGN() and __aligned(), into arbitrary user space
namespace.  This really isn't safe or acceptable, especially since those
symbols are highly generic.
...
When these structures are forced-aligned, they will in fact have padding
automatically added by the compiler to an 8-byte boundary anyway, so
mic_aligned_size() does nothing.
...

Reported-by: H Peter Anvin <h.peter.anvin@intel.com>
Reviewed-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Nikhil Rao <nikhil.rao@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-27 11:03:38 -08:00
Ashutosh Dixit
286c24028c misc: mic: Bug fix for sysfs poll usage.
MIC user space daemon poll's on sysfs changes. The documentation for
sysfs_poll(...) in fs/sysfs/file.c states that "Once poll/select
indicates that the value has changed, you need to close and re-open the
file, or seek to 0 and read again". This step was missed out earlier and
resulted in the daemon spinning continuously rather than getting blocked
in 'poll'. This bug was exposed by commit aea585ef8f introduced as
part of sysfs changes in 3.13-rc1. A seek to 0 has been introduced to
fix it.

Reviewed-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-27 11:03:38 -08:00
Alexander Shiyan
976358e234 Input: add a new driver for GPIO beeper
This patch adds a new driver for the beeper controlled via GPIO pin.
The driver does not depend on the architecture and is positioned as
a replacement for the specific drivers that are used for this function.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-11-26 15:54:49 -08:00
Tony Lindgren
9cb238c00b mmc: omap: Fix I2C dependency and make driver usable with device tree
Some features can be configured by the companion I2C chips,
which may not be available at the probe time. Fix the issue
by returning -EPROBE_DEFER when the MMC controller slots
are not configured.

While at it, let's also add minimal device tree support so
omap24xx platforms can use this driver without legacy mode
since we claim to support device tree for mach-omap2 based
systems.

Although adding the minimal device tree support is not strictly
a fix, it does remove one of the last blockers for dropping a
bunch of legacy platform data for mach-omap2.

Cc: linux-mmc@vger.kernel.org
Acked-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2013-11-26 15:51:16 -08:00
Lee Jones
0a05ef0ec1 dma: ste_dma40: Expand DT binding to accept 'high-priority channel' flag
This is used for MSP (audio) devices which is about to be fully DT:ed.

Cc: devicetree@vger.kernel.org
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-26 21:01:58 +01:00
Andrzej Pietrasiewicz
25d8015177 usb: gadget: f_sourcesink: add configfs support
Add support for using the sourcesink function in gadgets composed with
configfs.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2013-11-26 13:47:41 -06:00
Andrzej Pietrasiewicz
c0501f47c6 usb: gadget: f_loopback: add configfs support
Add support for using the loopback USB function in gadgets composed with
configfs.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2013-11-26 13:46:13 -06:00
Linus Torvalds
0e4b0743bb Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
 "Mostly bugfixes and a few small code removals.  Worth pointing out is:

   - A handful of more fixes to get DT enablement working properly on
     OMAP, finding new breakage of things that don't work quite right
     yet without the traditional board files.  I expect a bit more of
     this to come in this release as people test on their hardware.
   - Implementation of power_down_finish() on vexpress, to make kexec
     work and to stop the MCPM core to produce a warning (the warning
     was new to 3.13-rc1).
   - A handful of minor fixes for various platforms"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: bcm2835: add missing #xxx-cells to I2C nodes
  ARM: dts: Add max77686 RTC interrupt to cros5250-common
  ARM: vexpress/TC2: Implement MCPM power_down_finish()
  ARM: tegra: Provide dummy powergate implementation
  ARM: omap: fix warning with LPAE build
  ARM: OMAP2+: Remove legacy omap4_twl6030_hsmmc_init
  ARM: OMAP2+: Remove legacy mux code for display.c
  ARM: OMAP2+: Fix undefined reference to set_cntfreq
  gpio: twl4030: Fix passing of pdata in the device tree case
  gpio: twl4030: Fix regression for twl gpio output
  ARM: OMAP2+: More randconfig fixes for reconfigure_io_chain
  ARM: dts: imx6qdl: disable spdif "rxtx5" clock option
  ARM: dts: Fix omap2 specific dtsi files by adding the missing entries
  ARM: OMAP2+: Fix GPMC and simplify bootloader timings for 8250 and smc91x
  i2c: omap: Fix missing device tree flags for omap2
2013-11-26 11:18:37 -08:00
Peter De Schrijver
76da314df6 clk: tegra124: Add support for Tegra124 clocks
Implement clock support for Tegra124.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
2013-11-26 18:46:54 +02:00