Commit Graph

401413 Commits

Author SHA1 Message Date
Ingo Molnar c90423d1de Merge branch 'sched/core' into core/locking, to prepare the kernel/locking/ file move
Conflicts:
	kernel/Makefile

There are conflicts in kernel/Makefile due to file moving in the
scheduler tree - resolve them.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06 07:50:37 +01:00
Peter Zijlstra b8a216269e sched: Move completion code from core.c to completion.c
Completions already have their own header file: linux/completion.h
Move the implementation out of kernel/sched/core.c and into its own
file: kernel/sched/completion.c.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-x2y49rmxu5dljt66ai2lcfuw@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06 07:49:19 +01:00
Peter Zijlstra b4145872f7 sched: Move wait code from core.c to wait.c
For some reason only the wait part of the wait api lives in
kernel/sched/wait.c and the wake part still lives in kernel/sched/core.c;
ammend this.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-ftycee88naznulqk7ei5mbci@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06 07:49:18 +01:00
Peter Zijlstra 7a6354e241 sched: Move wait.c into kernel/sched/
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-5q5yqvdaen0rmapwloeaotx3@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06 07:49:16 +01:00
Ingo Molnar ecf1f01432 Merge branch 'core/rcu' into core/locking, to prepare the kernel/locking/ file move
There are conflicts in lockdep.c due to RCU changes, and also the RCU
tree changes kernel/Makefile - so pre-merge it to ease the moving of
locking related .c files to kernel/locking/.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06 07:43:37 +01:00
Ingo Molnar 97c53b402f Linux 3.12
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Merge tag 'v3.12' into core/locking to pick up mutex upates

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06 06:39:45 +01:00
Linus Torvalds 5e01dc7b26 Linux 3.12 2013-11-03 15:41:51 -08:00
Linus Torvalds 17f6ee43c3 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS fixes from Ralf Baechle:
 "Three fixes across arch/mips with the most complex one being the GIC
  interrupt fix - at nine lines still not monster.  I'm confident this
  are the final MIPS patches even if there should go for an rc8"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: ralink: fix return value check in rt_timer_probe()
  MIPS: malta: Fix GIC interrupt offsets
  MIPS: Perf: Fix 74K cache map
2013-11-03 11:36:41 -08:00
Mathias Krause 9bf76ca325 ipc, msg: forbid negative values for "msg{max,mnb,mni}"
Negative message lengths make no sense -- so don't do negative queue
lenghts or identifier counts. Prevent them from getting negative.

Also change the underlying data types to be unsigned to avoid hairy
surprises with sign extensions in cases where those variables get
evaluated in unsigned expressions with bigger data types, e.g size_t.

In case a user still wants to have "unlimited" sizes she could just use
INT_MAX instead.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-03 10:53:11 -08:00
Linus Torvalds 9dc8c89dfb Last minute perf unbreakage for ARM modules; spent a day in linux-next.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull ARM kallsyms fix from Rusty Russell:
 "Last minute perf unbreakage for ARM modules; spent a day in
  linux-next"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  scripts/kallsyms: filter symbols not in kernel address space
2013-11-02 10:27:29 -07:00
Vineet Gupta 9c41f4eeb9 ARC: Incorrect mm reference used in vmalloc fault handler
A vmalloc fault needs to sync up PGD/PTE entry from init_mm to current
task's "active_mm".  ARC vmalloc fault handler however was using mm.

A vmalloc fault for non user task context (actually pre-userland, from
init thread's open for /dev/console) caused the handler to deref NULL mm
(for mm->pgd)

The reasons it worked so far is amazing:

1. By default (!SMP), vmalloc fault handler uses a cached value of PGD.
   In SMP that MMU register is repurposed hence need for mm pointer deref.

2. In pre-3.12 SMP kernel, the problem triggering vmalloc didn't exist in
   pre-userland code path - it was introduced with commit 20bafb3d23
   "n_tty: Move buffers into n_tty_data"

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: stable@vger.kernel.org    #3.10 and 3.11
Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-02 10:27:04 -07:00
Ming Lei f6537f2f0e scripts/kallsyms: filter symbols not in kernel address space
This patch uses CONFIG_PAGE_OFFSET to filter symbols which
are not in kernel address space because these symbols are
generally for generating code purpose and can't be run at
kernel mode, so we needn't keep them in /proc/kallsyms.

For example, on ARM there are some symbols which may be
linked in relocatable code section, then perf can't parse
symbols any more from /proc/kallsyms, this patch fixes the
problem (introduced b9b32bf70f)

Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@vger.kernel.org
2013-11-02 09:13:02 +10:30
Linus Torvalds 9581b7d268 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Two fixes:

   - Fix 'NMI handler took too long to run' false positives

     [ Genuine NMI overhead speedups will come for v3.13, this commit
       only fixes a measurement bug ]

   - Fix perf ring-buffer missed barrier causing (rare) ring-buffer data
     corruption on ppc64"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86: Fix NMI measurements
  perf: Fix perf ring buffer memory ordering
2013-11-01 12:54:51 -07:00
Linus Torvalds 9119e33e50 USB fixes for 3.12-final
Here is a set of patches that revert all of the changes done to the
 pl2303 USB serial driver in the 3.12-rc timeframe, as it turns out they
 break some devices that work just fine on 3.11.  As it's not a good idea
 to break working systems, drop them all and they will be reworked for
 future kernel versions such that there is no breakage.
 
 I've also included a MAINTAINERS update for the USB serial subsystem and
 a new device id for the ftdi_sio driver as well.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here is a set of patches that revert all of the changes done to the
  pl2303 USB serial driver in the 3.12-rc timeframe, as it turns out
  they break some devices that work just fine on 3.11.  As it's not a
  good idea to break working systems, drop them all and they will be
  reworked for future kernel versions such that there is no breakage.

  I've also included a MAINTAINERS update for the USB serial subsystem
  and a new device id for the ftdi_sio driver as well"

* tag 'usb-3.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: serial: ftdi_sio: add id for Z3X Box device
  USB: Maintainers change for usb serial drivers
  Revert "USB: pl2303: restrict the divisor based baud rate encoding method to the "HX" chip type"
  Revert "usb: pl2303: fix+improve the divsor based baud rate encoding method"
  Revert "usb: pl2303: do not round to the next nearest standard baud rate for the divisor based baud rate encoding method"
  Revert "usb: pl2303: remove 500000 baud from the list of standard baud rates"
  Revert "usb: pl2303: move the two baud rate encoding methods to separate functions"
  Revert "usb: pl2303: increase the allowed baud rate range for the divisor based encoding method"
  Revert "usb: pl2303: also use the divisor based baud rate encoding method for baud rates < 115200 with HX chips"
  Revert "usb: pl2303: add two comments concerning the supported baud rates with HX chips"
  Revert "pl2303: simplify the else-if contruct for type_1 chips in pl2303_startup()"
  Revert "pl2303: improve the chip type information output on startup"
  Revert "pl2303: improve the chip type detection/distinction"
  Revert "USB: pl2303: distinguish between original and cloned HX chips"
2013-11-01 12:23:56 -07:00
Linus Torvalds f9adfbfbf3 sound fixes #2 for 3.12-final
The fixes for random bugs that have been reported lately in the game:
 a few fixes in ASoC dpam and wm_hubs bugs spotted by Coverity, a
 one-liner HD-audio fixup, and a fix for Oops with DPCM.
 
 They are not so critically urgent bugs, but all small and safe.
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Merge tag 'sound-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound

Pull more sound fixes from Takashi Iwai:
 "The fixes for random bugs that have been reported lately in the game:
  a few fixes in ASoC dpam and wm_hubs bugs spotted by Coverity, a
  one-liner HD-audio fixup, and a fix for Oops with DPCM.

  They are not so critically urgent bugs, but all small and safe"

* tag 'sound-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: fix oops in snd_pcm_info() caused by ASoC DPCM
  ASoC: wm_hubs: Add missing break in hp_supply_event()
  ALSA: hda - Add a fixup for ASUS N76VZ
  ASoC: dapm: Return -ENOMEM in snd_soc_dapm_new_dai_widgets()
  ASoC: dapm: Fix source list debugfs outputs
2013-11-01 12:23:22 -07:00
Linus Torvalds 68e952d5f9 Merge tag 'clk-fixes-for-linus' of git://git.linaro.org/people/mturquette/linux
Pull clock subsystem fixes from Mike Turquette.

* tag 'clk-fixes-for-linus' of git://git.linaro.org/people/mturquette/linux:
  clk: fixup argument order when setting VCO parameters
  clk: socfpga: Fix incorrect sdmmc clock name
  clk: armada-370: fix tclk frequencies
  clk: nomadik: set all timers to use 2.4 MHz TIMCLK
2013-11-01 12:22:47 -07:00
Greg Thelen 6920a1bd03 memcg: remove incorrect underflow check
When a memcg is deleted mem_cgroup_reparent_charges() moves charged
memory to the parent memcg.  As of v3.11-9444-g3ea67d0 "memcg: add per
cgroup writeback pages accounting" there's bad pointer read.  The goal
was to check for counter underflow.  The counter is a per cpu counter
and there are two problems with the code:

 (1) per cpu access function isn't used, instead a naked pointer is used
     which easily causes oops.
 (2) the check doesn't sum all cpus

Test:
  $ cd /sys/fs/cgroup/memory
  $ mkdir x
  $ echo 3 > /proc/sys/vm/drop_caches
  $ (echo $BASHPID >> x/tasks && exec cat) &
  [1] 7154
  $ grep ^mapped x/memory.stat
  mapped_file 53248
  $ echo 7154 > tasks
  $ rmdir x
  <OOPS>

The fix is to remove the check.  It's currently dangerous and isn't
worth fixing it to use something expensive, such as
percpu_counter_sum(), for each reparented page.  __this_cpu_read() isn't
enough to fix this because there's no guarantees of the current cpus
count.  The only guarantees is that the sum of all per-cpu counter is >=
nr_pages.

Fixes: 3ea67d06e4 ("memcg: add per cgroup writeback pages accounting")
Reported-and-tested-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: Greg Thelen <gthelen@google.com>
Reviewed-by: Sha Zhengju <handai.szj@taobao.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-01 12:22:28 -07:00
Алексей Крамаренко e1466ad5b1 USB: serial: ftdi_sio: add id for Z3X Box device
Custom VID/PID for Z3X Box device, popular tool for cellphone flashing.

Signed-off-by: Alexey E. Kramarenko <alexeyk13@yandex.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:33:56 -07:00
Greg KH f896b7968b USB: Maintainers change for usb serial drivers
Johan has been conned^Wgracious in accepting the maintainership of the
USB serial drivers, especially as he's been doing all of the real work
for the past few years.

At the same time, remove a bunch of old entries for USB serial drivers
that don't make sense anymore, given that the developers are no longer
around, and individual driver maintainerships for tiny things like this
is pretty pointless.

Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:20:37 -07:00
Greg Kroah-Hartman 54dc5792ea Revert "USB: pl2303: restrict the divisor based baud rate encoding method to the "HX" chip type"
This reverts commit b8bdad6082.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:19:56 -07:00
Greg Kroah-Hartman 1796a22876 Revert "usb: pl2303: fix+improve the divsor based baud rate encoding method"
This reverts commit 57ce61aad7.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:19:45 -07:00
Greg Kroah-Hartman 7e12a6fcbf Revert "usb: pl2303: do not round to the next nearest standard baud rate for the divisor based baud rate encoding method"
This reverts commit 75417d9f99.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:19:34 -07:00
Greg Kroah-Hartman 336b9daf90 Revert "usb: pl2303: remove 500000 baud from the list of standard baud rates"
This reverts commit b9208c721c.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:19:24 -07:00
Greg Kroah-Hartman 692ed4ddf0 Revert "usb: pl2303: move the two baud rate encoding methods to separate functions"
This reverts commit e917ba01d6.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:19:03 -07:00
Greg Kroah-Hartman 92dfe41088 Revert "usb: pl2303: increase the allowed baud rate range for the divisor based encoding method"
This reverts commit b5c16c6a03.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:18:47 -07:00
Greg Kroah-Hartman e2afb1d666 Revert "usb: pl2303: also use the divisor based baud rate encoding method for baud rates < 115200 with HX chips"
This reverts commit 61fa8d694b.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:18:38 -07:00
Greg Kroah-Hartman 233c3dda5c Revert "usb: pl2303: add two comments concerning the supported baud rates with HX chips"
This reverts commit c23bda365d.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:18:25 -07:00
Greg Kroah-Hartman 281393ad0b Revert "pl2303: simplify the else-if contruct for type_1 chips in pl2303_startup()"
This reverts commit 73b583af59.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:18:10 -07:00
Greg Kroah-Hartman b52e111363 Revert "pl2303: improve the chip type information output on startup"
This reverts commit a77a8c23e4.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:17:50 -07:00
Greg Kroah-Hartman e8bbd5c42b Revert "pl2303: improve the chip type detection/distinction"
This reverts commit 034d1527ad.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:16:09 -07:00
Greg Kroah-Hartman 09169197c9 Revert "USB: pl2303: distinguish between original and cloned HX chips"
This reverts commit 7d26a78f62.

Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip.  This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Frank Schäfer <fschaefer.oss@googlemail.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 09:12:52 -07:00
Heiko Carstens 7d716456a0 sched/wait: Fix __wait_event_interruptible_lock_irq_timeout()
__wait_event_interruptible_lock_irq_timeout() needs the timeout
parameter passed instead of "ret".

This magically compiled since the only user has a local ret
variable. Luckily we got a build warning:

  CC      drivers/s390/scsi/zfcp_qdio.o
  drivers/s390/scsi/zfcp_qdio.c: In function 'zfcp_qdio_sbal_get':
  include/linux/wait.h:780:15: warning: 'ret' may be used uninitialized

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20131031114814.GB5551@osiris
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-01 08:42:44 +01:00
Ingo Molnar fb10d5b7ef Merge branch 'linus' into sched/core
Resolve cherry-picking conflicts:

Conflicts:
	mm/huge_memory.c
	mm/memory.c
	mm/mprotect.c

See this upstream merge commit for more details:

  52469b4fcd Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-01 08:24:41 +01:00
Linus Torvalds 4f794ee8c4 Merge branch 'akpm' (fixes from Andrew Morton)
Merge four more fixes from Andrew Morton.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  lib/scatterlist.c: don't flush_kernel_dcache_page on slab page
  mm: memcg: fix test for child groups
  mm: memcg: lockdep annotation for memcg OOM lock
  mm: memcg: use proper memcg in limit bypass
2013-10-31 16:58:23 -07:00
Ming Lei 3d77b50c58 lib/scatterlist.c: don't flush_kernel_dcache_page on slab page
Commit b1adaf65ba ("[SCSI] block: add sg buffer copy helper
functions") introduces two sg buffer copy helpers, and calls
flush_kernel_dcache_page() on pages in SG list after these pages are
written to.

Unfortunately, the commit may introduce a potential bug:

 - Before sending some SCSI commands, kmalloc() buffer may be passed to
   block layper, so flush_kernel_dcache_page() can see a slab page
   finally

 - According to cachetlb.txt, flush_kernel_dcache_page() is only called
   on "a user page", which surely can't be a slab page.

 - ARCH's implementation of flush_kernel_dcache_page() may use page
   mapping information to do optimization so page_mapping() will see the
   slab page, then VM_BUG_ON() is triggered.

Aaro Koskinen reported the bug on ARM/kirkwood when DEBUG_VM is enabled,
and this patch fixes the bug by adding test of '!PageSlab(miter->page)'
before calling flush_kernel_dcache_page().

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Tested-by: Simon Baatz <gmbnomis@gmail.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Tejun Heo <tj@kernel.org>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>	[3.2+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-31 16:58:13 -07:00
Johannes Weiner 696ac172ff mm: memcg: fix test for child groups
When memcg code needs to know whether any given memcg has children, it
uses the cgroup child iteration primitives and returns true/false
depending on whether the iteration loop is executed at least once or
not.

Because a cgroup's list of children is RCU protected, these primitives
require the RCU read-lock to be held, which is not the case for all
memcg callers.  This results in the following splat when e.g.  enabling
hierarchy mode:

  WARNING: CPU: 3 PID: 1 at kernel/cgroup.c:3043 css_next_child+0xa3/0x160()
  CPU: 3 PID: 1 Comm: systemd Not tainted 3.12.0-rc5-00117-g83f11a9-dirty #18
  Hardware name: LENOVO 3680B56/3680B56, BIOS 6QET69WW (1.39 ) 04/26/2012
  Call Trace:
    dump_stack+0x54/0x74
    warn_slowpath_common+0x78/0xa0
    warn_slowpath_null+0x1a/0x20
    css_next_child+0xa3/0x160
    mem_cgroup_hierarchy_write+0x5b/0xa0
    cgroup_file_write+0x108/0x2a0
    vfs_write+0xbd/0x1e0
    SyS_write+0x4c/0xa0
    system_call_fastpath+0x16/0x1b

In the memcg case, we only care about children when we are attempting to
modify inheritable attributes interactively.  Racing with deletion could
mean a spurious -EBUSY, no problem.  Racing with addition is handled
just fine as well through the memcg_create_mutex: if the child group is
not on the list after the mutex is acquired, it won't be initialized
from the parent's attributes until after the unlock.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-31 16:58:13 -07:00
Johannes Weiner 0056f4e66a mm: memcg: lockdep annotation for memcg OOM lock
The memcg OOM lock is a mutex-type lock that is open-coded due to
memcg's special needs.  Add annotations for lockdep coverage.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-31 16:58:13 -07:00
Johannes Weiner 3168ecbe1c mm: memcg: use proper memcg in limit bypass
Commit 84235de394 ("fs: buffer: move allocation failure loop into the
allocator") allowed __GFP_NOFAIL allocations to bypass the limit if they
fail to reclaim enough memory for the charge.  But because the main test
case was on a 3.2-based system, the patch missed the fact that on newer
kernels the charge function needs to return root_mem_cgroup when
bypassing the limit, and not NULL.  This will corrupt whatever memory is
at NULL + percpu pointer offset.  Fix this quickly before problems are
reported.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-31 16:58:13 -07:00
Linus Torvalds 358eec1824 vfs: decrapify dput(), fix cache behavior under normal load
We do not want to dirty the dentry->d_flags cacheline in dput() just to
set the DCACHE_REFERENCED flag when it is already set in the common case
anyway.  This way the first cacheline of the dentry (which contains the
RCU lookup information etc) can stay shared among multiple CPU's.

This finishes off some of the details of all the scalability patches
merged during the merge window.

Also don't mark dentry_kill() for inlining, since it's the uncommon path
and inlining it just makes the common path slower due to extra function
entry/exit overhead.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-31 15:43:02 -07:00
Linus Torvalds 0baab4fd6d i915: fix compiler warning
The last i915 drm update brought with it this annoying warning

  drivers/gpu/drm/i915/intel_crt.c: In function ‘intel_crt_get_config’:
  drivers/gpu/drm/i915/intel_crt.c:110:21: warning: unused variable ‘dev’ [-Wunused-variable]
    struct drm_device *dev = encoder->base.dev;
                       ^

introduced by commit 7195a50b5c ("drm/i915: Add HSW CRT output readout
support").

Remove the offending pointless variable.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-31 15:28:23 -07:00
Linus Torvalds 52469b4fcd Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull NUMA balancing memory corruption fixes from Ingo Molnar:
 "So these fixes are definitely not something I'd like to sit on, but as
  I said to Mel at the KS the timing is quite tight, with Linus planning
  v3.12-final within a week.

  Fedora-19 is affected:

   comet:~> grep NUMA_BALANCING /boot/config-3.11.3-201.fc19.x86_64

   CONFIG_ARCH_SUPPORTS_NUMA_BALANCING=y
   CONFIG_NUMA_BALANCING_DEFAULT_ENABLED=y
   CONFIG_NUMA_BALANCING=y

  AFAICS Ubuntu will be affected as well, once it updates the kernel:

   hubble:~> grep NUMA_BALANCING /boot/config-3.8.0-32-generic

   CONFIG_ARCH_SUPPORTS_NUMA_BALANCING=y
   CONFIG_NUMA_BALANCING_DEFAULT_ENABLED=y
   CONFIG_NUMA_BALANCING=y

  These 6 commits are a minimalized set of cherry-picks needed to fix
  the memory corruption bugs.  All commits are fixes, except "mm: numa:
  Sanitize task_numa_fault() callsites" which is a cleanup that made two
  followup fixes simpler.

  I've done targeted testing with just this SHA1 to try to make sure
  there are no cherry-picking artifacts.  The original non-cherry-picked
  set of fixes were exposed to linux-next for a couple of weeks"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  mm: Account for a THP NUMA hinting update as one PTE update
  mm: Close races between THP migration and PMD numa clearing
  mm: numa: Sanitize task_numa_fault() callsites
  mm: Prevent parallel splits during THP migration
  mm: Wait for THP migrations to complete during NUMA hinting faults
  mm: numa: Do not account for a hinting fault if we raced
2013-10-31 15:21:26 -07:00
Linus Torvalds 026f8f612a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:
 "A bit later than I would want, but the changes are very minor - a few
  new device IDs for new hardware in existing drivers, fix for battery
  in Wacom devices not be considered system battery and cause emergency
  hibernations, and a couple of other bug fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: ALPS - add support for model found on Dell XT2
  Input: wacom - add support for ISDv4 0x10E sensor
  Input: wacom - add support for ISDv4 0x10F sensor
  Input: wacom - export battery scope
  Input: cm109 - convert high volume dev_err() to dev_err_ratelimited()
  Input: move name/timer init to input_alloc_dev()
  Input: i8042 - i8042_flush fix for a full 8042 buffer
  Input: pxa27x_keypad - fix NULL pointer dereference
2013-10-31 10:38:59 -07:00
Linus Torvalds e7647027bd Last-minute ACPI and power management fixes for 3.12
- Revert epoll and select commits related to the freezer, introduced
    during the 3.11 cycle, that cause mysterious user space breakage
    to occur during resume from suspend to RAM for multiple users of
    32-bit x86 systems.  Material for 3.11.y stable kernels.
 
  - Revert a recent ACPI-based PCI hotplug (ACPIPHP) commit that was
    part of boot problem fixes for one machine, but turns out to cause
    issues with hotplug on Thunderbolt chains with multiple devices.
    It also turns out to be unnecessary after another fix in the
    same area that went in later.  From Mika Westerberg.
 
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Merge tag 'pm+acpi-3.12-late' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael J Wysocki:
 "Last-minute ACPI and power management fixes for 3.12

   - Revert epoll and select commits related to the freezer, introduced
     during the 3.11 cycle, that cause mysterious user space breakage to
     occur during resume from suspend to RAM for multiple users of
     32-bit x86 systems.  Material for 3.11.y stable kernels.

   - Revert a recent ACPI-based PCI hotplug (ACPIPHP) commit that was
     part of boot problem fixes for one machine, but turns out to cause
     issues with hotplug on Thunderbolt chains with multiple devices.
     It also turns out to be unnecessary after another fix in the same
     area that went in later.  From Mika Westerberg"

* tag 'pm+acpi-3.12-late' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  Revert "ACPI / hotplug / PCI: Avoid doing too much for spurious notifies"
  Revert "select: use freezable blocking call"
  Revert "epoll: use freezable blocking call"
2013-10-31 10:13:28 -07:00
Russell King a4461f41b9 ALSA: fix oops in snd_pcm_info() caused by ASoC DPCM
Unable to handle kernel NULL pointer dereference at virtual address 00000008
pgd = d5300000
[00000008] *pgd=0d265831, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [#1] PREEMPT ARM
CPU: 0 PID: 2295 Comm: vlc Not tainted 3.11.0+ #755
task: dee74800 ti: e213c000 task.ti: e213c000
PC is at snd_pcm_info+0xc8/0xd8
LR is at 0x30232065
pc : [<c031b52c>]    lr : [<30232065>]    psr: a0070013
sp : e213dea8  ip : d81cb0d0  fp : c05f7678
r10: c05f7770  r9 : fffffdfd  r8 : 00000000
r7 : d8a968a8  r6 : d8a96800  r5 : d8a96200  r4 : d81cb000
r3 : 00000000  r2 : d81cb000  r1 : 00000001  r0 : d8a96200
Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c5387d  Table: 15300019  DAC: 00000015
Process vlc (pid: 2295, stack limit = 0xe213c248)
[<c031b52c>] (snd_pcm_info) from [<c031b570>] (snd_pcm_info_user+0x34/0x9c)
[<c031b570>] (snd_pcm_info_user) from [<c03164a4>] (snd_pcm_control_ioctl+0x274/0x280)
[<c03164a4>] (snd_pcm_control_ioctl) from [<c0311458>] (snd_ctl_ioctl+0xc0/0x55c)
[<c0311458>] (snd_ctl_ioctl) from [<c00eca84>] (do_vfs_ioctl+0x80/0x31c)
[<c00eca84>] (do_vfs_ioctl) from [<c00ecd5c>] (SyS_ioctl+0x3c/0x60)
[<c00ecd5c>] (SyS_ioctl) from [<c000e500>] (ret_fast_syscall+0x0/0x48)
Code: e1a00005 e59530dc e3a01001 e1a02004 (e5933008)
---[ end trace cb3d9bdb8dfefb3c ]---

This is provoked when the ASoC front end is open along with its backend,
(which causes the backend to have a runtime assigned to it) and then the
SNDRV_CTL_IOCTL_PCM_INFO is requested for the (visible) backend device.

Resolve this by ensuring that ASoC internal backend devices are not
visible to userspace, just as the commentry for snd_pcm_new_internal()
says it should be.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mark Brown <broonie@linaro.org>
Cc: <stable@vger.kernel.org> [v3.4+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-10-31 17:36:47 +01:00
Wei Yongjun cd5d58108e MIPS: ralink: fix return value check in rt_timer_probe()
In case of error, the function devm_request_and_ioremap() returns NULL
pointer not ERR_PTR(). Fix it by using devm_ioremap_resource() instead
of devm_request_and_ioremap().

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: John Crispin <blogic@openwrt.org>
Cc: grant.likely@linaro.org
Cc: rob.herring@calxeda.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6098/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-10-31 12:38:34 +01:00
Oleg Nesterov 6a716c90a5 hung_task debugging: Add tracepoint to report the hang
Currently check_hung_task() prints a warning if it detects the
problem, but it is not convenient to watch the system logs if
user-space wants to be notified about the hang.

Add the new trace_sched_process_hang() into check_hung_task(),
this way a user-space monitor can easily wait for the hang and
potentially resolve a problem.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Dave Sullivan <dsulliva@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20131019161828.GA7439@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-31 11:16:18 +01:00
Yunkang Tang 5beea882e6 Input: ALPS - add support for model found on Dell XT2
This patch adds support for touchpad found on Dell XT2. It's a dual device
with device ID: 73, 00, 14, that comply with "ALPS_PROTO_V2".

Signed-off-by: Yunkang Tang <yunkang.tang@cn.alps.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-10-31 00:59:20 -07:00
Dave Airlie 74c85e1357 Merge branch 'drm-fixes-3.12' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
Just a few small fixes for radeon (audio regression fix,
stability fix, and an endian bug noticed by coverity).

* 'drm-fixes-3.12' of git://people.freedesktop.org/~agd5f/linux:
  drm/radeon/dpm: fix incompatible casting on big endian
  drm/radeon: disable bapm on KB
  drm/radeon: use sw CTS/N values for audio on DCE4+
2013-10-31 15:29:10 +10:00
Linus Torvalds 12aee278b5 Merge branch 'akpm' (fixes from Andrew Morton)
Merge three fixes from Andrew Morton.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  memcg: use __this_cpu_sub() to dec stats to avoid incorrect subtrahend casting
  percpu: fix this_cpu_sub() subtrahend casting for unsigneds
  mm/pagewalk.c: fix walk_page_range() access of wrong PTEs
2013-10-30 14:27:10 -07:00
Greg Thelen 5e8cfc3c75 memcg: use __this_cpu_sub() to dec stats to avoid incorrect subtrahend casting
As of commit 3ea67d06e4 ("memcg: add per cgroup writeback pages
accounting") memcg counter errors are possible when moving charged
memory to a different memcg.  Charge movement occurs when processing
writes to memory.force_empty, moving tasks to a memcg with
memcg.move_charge_at_immigrate=1, or memcg deletion.

An example showing error after memory.force_empty:

  $ cd /sys/fs/cgroup/memory
  $ mkdir x
  $ rm /data/tmp/file
  $ (echo $BASHPID >> x/tasks && exec mmap_writer /data/tmp/file 1M) &
  [1] 13600
  $ grep ^mapped x/memory.stat
  mapped_file 1048576
  $ echo 13600 > tasks
  $ echo 1 > x/memory.force_empty
  $ grep ^mapped x/memory.stat
  mapped_file 4503599627370496

mapped_file should end with 0.
  4503599627370496 == 0x10,0000,0000,0000 == 0x100,0000,0000 pages
  1048576          == 0x10,0000           == 0x100 pages

This issue only affects the source memcg on 64 bit machines; the
destination memcg counters are correct.  So the rmdir case is not too
important because such counters are soon disappearing with the entire
memcg.  But the memcg.force_empty and memory.move_charge_at_immigrate=1
cases are larger problems as the bogus counters are visible for the
(possibly long) remaining life of the source memcg.

The problem is due to memcg use of __this_cpu_from(.., -nr_pages), which
is subtly wrong because it subtracts the unsigned int nr_pages (either
-1 or -512 for THP) from a signed long percpu counter.  When
nr_pages=-1, -nr_pages=0xffffffff.  On 64 bit machines stat->count[idx]
is signed 64 bit.  So memcg's attempt to simply decrement a count (e.g.
from 1 to 0) boils down to:

  long count = 1
  unsigned int nr_pages = 1
  count += -nr_pages  /* -nr_pages == 0xffff,ffff */
  count is now 0x1,0000,0000 instead of 0

The fix is to subtract the unsigned page count rather than adding its
negation.  This only works once "percpu: fix this_cpu_sub() subtrahend
casting for unsigneds" is applied to fix this_cpu_sub().

Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-30 14:27:03 -07:00