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323981 commits

Author SHA1 Message Date
Paul E. McKenney
7e5c2dfb4d rcu: Make rcutree module parameters visible in sysfs
The module parameters blimit, qhimark, and qlomark (and more
recently, rcu_fanout_leaf) have permission masks of zero, so
that their values are not visible from sysfs.  This is unnecessary
and inconvenient to administrators who might like an easy way to
see what these values are on a running system.  This commit therefore
sets their permission masks to 0444, allowing them to be read but
not written.

Reported-by: Rusty Russell <rusty@ozlabs.org>
Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:55 -07:00
Paul E. McKenney
d40011f601 rcu: Control grace-period duration from sysfs
Although almost everyone is well-served by the defaults, some uses of RCU
benefit from shorter grace periods, while others benefit more from the
greater efficiency provided by longer grace periods.  Situations requiring
a large number of grace periods to elapse (and wireshark startup has
been called out as an example of this) are helped by lower-latency
grace periods.  Furthermore, in some embedded applications, people are
willing to accept a small degradation in update efficiency (due to there
being more of the shorter grace-period operations) in order to gain the
lower latency.

In contrast, those few systems with thousands of CPUs need longer grace
periods because the CPU overhead of a grace period rises roughly
linearly with the number of CPUs.  Such systems normally do not make
much use of facilities that require large numbers of grace periods to
elapse, so this is a good tradeoff.

Therefore, this commit allows the durations to be controlled from sysfs.
There are two sysfs parameters, one named "jiffies_till_first_fqs" that
specifies the delay in jiffies from the end of grace-period initialization
until the first attempt to force quiescent states, and the other named
"jiffies_till_next_fqs" that specifies the delay (again in jiffies)
between subsequent attempts to force quiescent states.  They both default
to three jiffies, which is compatible with the old hard-coded behavior.

At some future time, it may be possible to automatically increase the
grace-period length with the number of CPUs, but we do not yet have
sufficient data to do a good job.  Preliminary data indicates that we
should add an addiitonal jiffy to each of the delays for every 200 CPUs
in the system, but more experimentation is needed.  For now, the number
of systems with more than 1,000 CPUs is small enough that this can be
relegated to boot-time hand tuning.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:54 -07:00
Paul E. McKenney
394f2769aa rcu: Prevent force_quiescent_state() memory contention
Large systems running RCU_FAST_NO_HZ kernels see extreme memory
contention on the rcu_state structure's ->fqslock field.  This
can be avoided by disabling RCU_FAST_NO_HZ, either at compile time
or at boot time (via the nohz kernel boot parameter), but large
systems will no doubt become sensitive to energy consumption.
This commit therefore uses a combining-tree approach to spread the
memory contention across new cache lines in the leaf rcu_node structures.
This can be thought of as a tournament lock that has only a try-lock
acquisition primitive.

The effect on small systems is minimal, because such systems have
an rcu_node "tree" consisting of a single node.  In addition, this
functionality is not used on fastpaths.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:54 -07:00
Paul E. McKenney
4605c0143c rcu: Adjust debugfs tracing for kthread-based quiescent-state forcing
Moving quiescent-state forcing into a kthread dispenses with the need
for the ->n_rp_need_fqs field, so this commit removes it.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:54 -07:00
Paul E. McKenney
b4be093fee rcu: Allow RCU quiescent-state forcing to be preempted
RCU quiescent-state forcing is currently carried out without preemption
points, which can result in excessive latency spikes on large systems
(many hundreds or thousands of CPUs).  This patch therefore inserts
a voluntary preemption point into force_qs_rnp(), which should greatly
reduce the magnitude of these spikes.

Reported-by: Mike Galbraith <mgalbraith@suse.de>
Reported-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:54 -07:00
Paul E. McKenney
4cdfc175c2 rcu: Move quiescent-state forcing into kthread
As the first step towards allowing quiescent-state forcing to be
preemptible, this commit moves RCU quiescent-state forcing into the
same kthread that is now used to initialize and clean up after grace
periods.  This is yet another step towards keeping scheduling
latency down to a dull roar.

Updated to change from raw_spin_lock_irqsave() to raw_spin_lock_irq()
and to remove the now-unused rcu_state structure fields as suggested by
Peter Zijlstra.

Reported-by: Mike Galbraith <mgalbraith@suse.de>
Reported-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-09-23 07:41:54 -07:00
Dimitri Sivanich
b402b73b3a rcu: Segregate rcu_state fields to improve cache locality
The fields in the rcu_state structure that are protected by the
root rcu_node structure's ->lock can share a cache line with the
fields protected by ->onofflock.  This can result in excessive
memory contention on large systems, so this commit applies
____cacheline_internodealigned_in_smp to the ->onofflock field in
order to segregate them.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Dimitri Sivanich <sivanich@sgi.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:53 -07:00
Paul E. McKenney
b626c1b689 rcu: Provide OOM handler to motivate lazy RCU callbacks
In kernels built with CONFIG_RCU_FAST_NO_HZ=y, CPUs can accumulate a
large number of lazy callbacks, which as the name implies will be slow
to be invoked.  This can be a problem on small-memory systems, where the
default 6-second sleep for CPUs having only lazy RCU callbacks could well
be fatal.  This commit therefore installs an OOM hander that ensures that
every CPU with lazy callbacks has at least one non-lazy callback, in turn
ensuring timely advancement for these callbacks.

Updated to fix bug that disabled OOM killing, noted by Lai Jiangshan.

Updated to push the for_each_rcu_flavor() loop into rcu_oom_notify_cpu(),
thus reducing the number of IPIs, as suggested by Steven Rostedt.  Also
to make the for_each_online_cpu() loop be preemptible.  (Later, it might
be good to use smp_call_function(), as suggested by Peter Zijlstra.)

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Sasha Levin <levinsasha928@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:53 -07:00
Paul E. McKenney
bfa00b4c40 rcu: Prevent offline CPUs from executing RCU core code
Earlier versions of RCU invoked the RCU core from the CPU_DYING notifier
in order to note a quiescent state for the outgoing CPU.  Because the
CPU is marked "offline" during the execution of the CPU_DYING notifiers,
the RCU core had to tolerate being invoked from an offline CPU.  However,
commit b1420f1c (Make rcu_barrier() less disruptive) left only tracing
code in the CPU_DYING notifier, so the RCU core need no longer execute
on offline CPUs.  This commit therefore enforces this restriction.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:53 -07:00
Paul E. McKenney
7fdefc10e1 rcu: Break up rcu_gp_kthread() into subfunctions
Then rcu_gp_kthread() function is too large and furthermore needs to
have the force_quiescent_state() code pulled in.  This commit therefore
breaks up rcu_gp_kthread() into rcu_gp_init() and rcu_gp_cleanup().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:53 -07:00
Paul E. McKenney
c856bafae7 rcu: Allow RCU grace-period cleanup to be preempted
RCU grace-period cleanup is currently carried out with interrupts
disabled, which can result in excessive latency spikes on large systems
(many hundreds or thousands of CPUs).  This patch therefore makes the
RCU grace-period cleanup be preemptible, including voluntary preemption
points, which should eliminate those latency spikes.  Similar spikes from
forcing of quiescent states will be dealt with similarly by later patches.

Updated to replace uses of spin_lock_irqsave() with spin_lock_irq(), as
suggested by Peter Zijlstra.

Reported-by: Mike Galbraith <mgalbraith@suse.de>
Reported-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:53 -07:00
Paul E. McKenney
cabc49c1ff rcu: Move RCU grace-period cleanup into kthread
As a first step towards allowing grace-period cleanup to be preemptible,
this commit moves the RCU grace-period cleanup into the same kthread
that is now used to initialize grace periods.  This is needed to keep
scheduling latency down to a dull roar.

[ paulmck: Get rid of stray spin_lock_irqsave() calls. ]

Reported-by: Mike Galbraith <mgalbraith@suse.de>
Reported-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:52 -07:00
Paul E. McKenney
755609a908 rcu: Allow RCU grace-period initialization to be preempted
RCU grace-period initialization is currently carried out with interrupts
disabled, which can result in 200-microsecond latency spikes on systems
on which RCU has been configured for 4096 CPUs.  This patch therefore
makes the RCU grace-period initialization be preemptible, which should
eliminate those latency spikes.  Similar spikes from grace-period cleanup
and the forcing of quiescent states will be dealt with similarly by later
patches.

Reported-by: Mike Galbraith <mgalbraith@suse.de>
Reported-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:52 -07:00
Paul E. McKenney
79bce67243 rcu: Prevent initialization-time quiescent-state race
The next step in reducing RCU's grace-period initialization latency on
large systems will make this initialization preemptible.  Unfortunately,
making the grace-period initialization subject to interrupts (let alone
preemption) exposes the following race on systems whose rcu_node tree
contains more than one node:

1.	CPU 31 starts initializing the grace period, including the
    	first leaf rcu_node structures, and is then preempted.

2.	CPU 0 refers to the first leaf rcu_node structure, and notes
    	that a new grace period has started.  It passes through a
    	quiescent state shortly thereafter, and informs the RCU core
    	of this rite of passage.

3.	CPU 0 enters an RCU read-side critical section, acquiring
    	a pointer to an RCU-protected data item.

4.	CPU 31 takes an interrupt whose handler removes the data item
	referenced by CPU 0 from the data structure, and registers an
	RCU callback in order to free it.

5.	CPU 31 resumes initializing the grace period, including its
    	own rcu_node structure.  In invokes rcu_start_gp_per_cpu(),
    	which advances all callbacks, including the one registered
    	in #4 above, to be handled by the current grace period.

6.	The remaining CPUs pass through quiescent states and inform
    	the RCU core, but CPU 0 remains in its RCU read-side critical
    	section, still referencing the now-removed data item.

7.	The grace period completes and all the callbacks are invoked,
    	including the one that frees the data item that CPU 0 is still
    	referencing.  Oops!!!

One way to avoid this race is to remove grace-period acceleration from
rcu_start_gp_per_cpu().  Now, the only reason for this acceleration was
to allow CPUs bringing RCU out of idle state to have their callbacks
invoked after only one grace period, rather than the two grace periods
that would otherwise be required.  But this acceleration does not
work when RCU grace-period initialization is moved to a kthread because
the CPU posting the callback is no longer necessarily the CPU that is
initializing the resulting grace period.

This commit therefore removes this now-pointless (and soon to be dangerous)
grace-period acceleration, thus avoiding the above race.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-09-23 07:41:52 -07:00
Paul E. McKenney
b3dbec76e5 rcu: Move RCU grace-period initialization into a kthread
As the first step towards allowing grace-period initialization to be
preemptible, this commit moves the RCU grace-period initialization
into its own kthread.  This is needed to keep large-system scheduling
latency at reasonable levels.

Also change raw_spin_lock_irqsave() to raw_spin_lock_irq() as suggested
by Peter Zijlstra in review comments.

Reported-by: Mike Galbraith <mgalbraith@suse.de>
Reported-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:41:52 -07:00
Paul E. McKenney
a10d206ef1 rcu: Fix day-one dyntick-idle stall-warning bug
Each grace period is supposed to have at least one callback waiting
for that grace period to complete.  However, if CONFIG_NO_HZ=n, an
extra callback-free grace period is no big problem -- it will chew up
a tiny bit of CPU time, but it will complete normally.  In contrast,
CONFIG_NO_HZ=y kernels have the potential for all the CPUs to go to
sleep indefinitely, in turn indefinitely delaying completion of the
callback-free grace period.  Given that nothing is waiting on this grace
period, this is also not a problem.

That is, unless RCU CPU stall warnings are also enabled, as they are
in recent kernels.  In this case, if a CPU wakes up after at least one
minute of inactivity, an RCU CPU stall warning will result.  The reason
that no one noticed until quite recently is that most systems have enough
OS noise that they will never remain absolutely idle for a full minute.
But there are some embedded systems with cut-down userspace configurations
that consistently get into this situation.

All this begs the question of exactly how a callback-free grace period
gets started in the first place.  This can happen due to the fact that
CPUs do not necessarily agree on which grace period is in progress.
If a CPU still believes that the grace period that just completed is
still ongoing, it will believe that it has callbacks that need to wait for
another grace period, never mind the fact that the grace period that they
were waiting for just completed.  This CPU can therefore erroneously
decide to start a new grace period.  Note that this can happen in
TREE_RCU and TREE_PREEMPT_RCU even on a single-CPU system:  Deadlock
considerations mean that the CPU that detected the end of the grace
period is not necessarily officially informed of this fact for some time.

Once this CPU notices that the earlier grace period completed, it will
invoke its callbacks.  It then won't have any callbacks left.  If no
other CPU has any callbacks, we now have a callback-free grace period.

This commit therefore makes CPUs check more carefully before starting a
new grace period.  This new check relies on an array of tail pointers
into each CPU's list of callbacks.  If the CPU is up to date on which
grace periods have completed, it checks to see if any callbacks follow
the RCU_DONE_TAIL segment, otherwise it checks to see if any callbacks
follow the RCU_WAIT_TAIL segment.  The reason that this works is that
the RCU_WAIT_TAIL segment will be promoted to the RCU_DONE_TAIL segment
as soon as the CPU is officially notified that the old grace period
has ended.

This change is to cpu_needs_another_gp(), which is called in a number
of places.  The only one that really matters is in rcu_start_gp(), where
the root rcu_node structure's ->lock is held, which prevents any
other CPU from starting or completing a grace period, so that the
comparison that determines whether the CPU is missing the completion
of a grace period is stable.

Reported-by: Becky Bruce <bgillbruce@gmail.com>
Reported-by: Subodh Nijsure <snijsure@grid-net.com>
Reported-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Paul Walmsley <paul@pwsan.com>  # OMAP3730, OMAP4430
Cc: stable@vger.kernel.org
2012-09-23 07:31:52 -07:00
Al Viro
c5aa1e554a close the race in nlmsvc_free_block()
we need to grab mutex before the reference counter reaches 0

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-22 20:48:20 -04:00
Al Viro
156cacb1d0 do_add_mount()/umount -l races
normally we deal with lock_mount()/umount races by checking that
mountpoint to be is still in our namespace after lock_mount() has
been done.  However, do_add_mount() skips that check when called
with MNT_SHRINKABLE in flags (i.e. from finish_automount()).  The
reason is that ->mnt_ns may be a temporary namespace created exactly
to contain automounts a-la NFS4 referral handling.  It's not the
namespace of the caller, though, so check_mnt() would fail here.
We still need to check that ->mnt_ns is non-NULL in that case,
though.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-22 20:48:18 -04:00
Xiaodong Xu
2b018d57ff pppoe: drop PPPOX_ZOMBIEs in pppoe_release
When PPPOE is running over a virtual ethernet interface (e.g., a
bonding interface) and the user tries to delete the interface in case
the PPPOE state is ZOMBIE, the kernel will loop forever while
unregistering net_device for the reference count is not decreased to
zero which should have been done with dev_put().

Signed-off-by: Xiaodong Xu <stid.smth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-22 15:49:31 -04:00
Linus Torvalds
e5e77cf9f9 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS fixes from Ralf Baechle:
 "Random fixes across arch/mips, essentially.

  One fix for an issue in get_user_pages_fast() which previously was
  discovered on x86, a miscalculation in the support for the MIPS MT
  hardware multithreading support, the RTC support for the Malta and a
  fix for a spurious interrupt issue that seems to bite only very
  special Malta configurations."

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: Malta: Don't crash on spurious interrupt.
  MIPS: Malta: Remove RTC Data Mode bootstrap breakage
  MIPS: mm: Add compound tail page _mapcount when mapped
  MIPS: CMP/SMTC: Fix tc_id calculation
2012-09-22 12:47:53 -07:00
Jiri Pirko
0b121fd28d team: send port changed when added
On some hw, link is not up during adding iface to team. That causes event
not being sent to userspace and that may cause confusion.
Fix this bug by sending port changed event once it's added to team.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-22 15:46:12 -04:00
Linus Torvalds
b3a297d15b Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM and clkdev fixes from Russell King:
 "Two patches for clkdev which resolve the long standing issue that the
  devm_* versions were dependent on clkdev, which they shouldn't have
  been.  Instead, they're dependent on HAVE_CLK instead, which implies
  that you're providing clk_get() and clk_put().

  A small fix to the ARM decompressor to ensure that the page tables are
  properly interpreted by the CPU, and reserve syscall 378 for kcmp (the
  checksyscalls.sh script is unfortunately currently broken so arch
  maintainers aren't getting notified of new syscalls...)

  Lastly, a larger fix for an issue between the common clk subsystem and
  smp_twd which causes warnings to be spat out."

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: reserve syscall 378 for kcmp
  ARM: 7535/1: Reprogram smp_twd based on new common clk framework notifiers
  ARM: 7537/1: clk: Fix release in devm_clk_put()
  ARM: 7532/1: decompressor: reset SCTLR.TRE for VMSA ARMv7 cores
  ARM: 7534/1: clk: Make the managed clk functions generically available
2012-09-22 12:40:16 -07:00
Linus Torvalds
cead24c118 Merge branch 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
Pull HID fixes from Jiri Kosina:
 "The most important fix is Logitech Unifying receiver regression in
  device enumeration fix from Nestor Lopez Casado.  In addition to that,
  there is a small memory leak fix for Thinkpad keyboard driver from
  Axel Lin."

* 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: Fix logitech-dj: missing Unifying device issue
  HID: lenovo-tpkbd: Fix memory leak in tpkbd_remove_tp()
2012-09-22 12:37:54 -07:00
Linus Torvalds
a4be6c77b5 Merge branch 'for-linus' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fix from Steve French.

* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix return value in cifsConvertToUTF16
2012-09-22 12:36:57 -07:00
Eric Dumazet
ab43ed8b74 ipv4: raw: fix icmp_filter()
icmp_filter() should not modify its input, or else its caller
would need to recompute ip_hdr() if skb->head is reallocated.

Use skb_header_pointer() instead of pskb_may_pull() and
change the prototype to make clear both sk and skb are const.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-22 15:35:05 -04:00
Peter Hüwe
9913b8c8f0 net/phy/bcm87xx: Add MODULE_LICENSE("GPL") to GPL driver
Currently the driver has no MODULE_LICENSE attribute in its source which
results in a kernel taint if I load this:

root@(none):~# modprobe bcm87xx
bcm87xx: module license 'unspecified' taints kernel.

Since the first lines of the source code clearly state:
 * This file is subject to the terms and conditions of the GNU General
 * Public License.  See the file "COPYING" in the main directory of this
 * archive for more details.
I think it's safe to add the MODULE_LICENSE("GPL") macro and thus remove
the kernel taint.

Cc: stable@vger.kernel.org
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-22 15:33:46 -04:00
John W. Linville
1199992df2 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem 2012-09-22 12:19:22 -04:00
Mark Brown
613dac31a6 Merge remote-tracking branches 'regmap/topic/cache' and 'regmap/topic/irq' into regmap-next 2012-09-22 12:02:05 -04:00
Nestor Lopez Casado
596264082f HID: Fix logitech-dj: missing Unifying device issue
This patch fixes an issue introduced after commit 4ea5454203
("HID: Fix race condition between driver core and ll-driver").

After that commit, hid-core discards any incoming packet that arrives while
hid driver's probe function is being executed.

This broke the enumeration process of hid-logitech-dj, that must receive
control packets in-band with the mouse and keyboard packets. Discarding mouse
or keyboard data at the very begining is usually fine, but it is not the case
for control packets.

This patch forces a re-enumeration of the paired devices when a packet arrives
that comes from an unknown device.

Based on a patch originally written by Benjamin Tissoires.

Cc: stable@vger.kernel.org   # v3.2+
Signed-off-by: Nestor Lopez Casado <nlopezcasad@logitech.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-09-22 10:58:48 +02:00
Axel Lin
391499801b HID: lenovo-tpkbd: Fix memory leak in tpkbd_remove_tp()
We need to kfree names for led_mute and led_micmute in tpkbd_remove_tp().

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Bernhard Seibold <mail@bernhard-seibold.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-09-22 10:58:36 +02:00
Alex Elder
5ce765a540 libceph: only kunmap kmapped pages
In write_partial_msg_pages(), pages need to be kmapped in order to
perform a CRC-32c calculation on them.  As an artifact of the way
this code used to be structured, the kunmap() call was separated
from the kmap() call and both were done conditionally.  But the
conditions under which the kmap() and kunmap() calls were made
differed, so there was a chance a kunmap() call would be done on a
page that had not been mapped.

The symptom of this was tripping a BUG() in kunmap_high() when
pkmap_count[nr] became 0.

Reported-by: Bryan K. Wright <bryan@virginia.edu>
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-09-21 20:49:26 -07:00
Alex Elder
340c7a2b2c rbd: drop dev reference on error in rbd_open()
If a read-only rbd device is opened for writing in rbd_open(), it
returns without dropping the just-acquired device reference.

Fix this by moving the read-only check before getting the reference.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-09-21 20:48:54 -07:00
Linus Torvalds
abef3bd710 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking updates from David Miller:
 "More bug fixes, nothing gets past these guys"

 1) More kernel info leaks found by Mathias Krause, this time in the
    IPSEC configuration layers.

 2) When IPSEC policies change, we do not properly make sure that cached
    routes (which could now be stale) throughout the system will be
    revalidated.  Fix this by generalizing the generation count
    invalidation scheme used by ipv4.  From Nicolas Dichtel.

 3) When repairing TCP sockets, we need to allow to restore not just the
    send window scale, but the receive one too.  Extend the existing
    interface to achieve this in a backwards compatible way.  From
    Andrey Vagin.

 4) A fix for FCOE scatter gather feature validation erroneously caused
    scatter gather to be disabled for things like AOE too.  From Ed L
    Cashin.

 5) Several cases of mishandling of error pointers, from Mathias Krause,
    Wei Yongjun, and Devendra Naga.

 6) Fix gianfar build, from Richard Cochran.

 7) CAP_NET_* failures should return -EPERM not -EACCES, from Zhao
    Hongjiang.

 8) Hardware reset fix in janz-ican3 CAN driver, from Ira W Snyder.

 9) Fix oops during rmmod in ti_hecc CAN driver, from Marc Kleine-Budde.

10) The removal of the conditional compilation of the clk support code
    in the stmmac driver broke things.  This is because the interfaces
    used are the ones that don't also perform the enable/disable of the
    clk.  Fix from Stefan Roese.

11) The QFQ packet scheduler can record out of range virtual start
    times, resulting later in misbehavior and even crashes.  Fix from
    Paolo Valente.

12) If MSG_WAITALL is used with IOAT DMA under TCP, we can wedge the
    receiver when the advertised receive window goes to zero.  Detect
    this case and force the processing of the IOAT DMA queue when it
    happens to avoid getting stuck.  Fix from Michal Kubecek.

13) batman-adv assumes that test_bit() returns only 0 or 1, but this is
    not true for x86 (which returns -1 or 0, via the 'sbb' instruction).
    Fix from Linus Lussing.

14) Fix small packet corruption in e1000, from Tushar Dave.

15) make_blackhole() in the IPSEC policy code can do one read unlock too
    many, fix from Li RongQing.

16) The new tcp_try_coalesce() code introduced a bug in TCP URG
    handling, fix from Eric Dumazet.

17) Fix memory leak in __netif_receive_skb() when doing zerocopy and
    when hit an OOM condition.  From Michael S Tsirkin.

18) netxen blindly deferences pdev->bus->self, which is not guarenteed
    to be non-NULL.  Fix from Nikolay Aleksandrov.

19) Fix a performance regression caused by mistakes in ipv6 checksum
    validation in the bnx2x driver, fix from Michal Schmidt.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (45 commits)
  net/stmmac: Use clk_prepare_enable and clk_disable_unprepare
  net: change return values from -EACCES to -EPERM
  net/irda: sh_sir: fix return value check in sh_sir_set_baudrate()
  stmmac: fix return value check in stmmac_open_ext_timer()
  gianfar: fix phc index build failure
  ipv6: fix return value check in fib6_add()
  bnx2x: remove false warning regarding interrupt number
  can: ti_hecc: fix oops during rmmod
  can: janz-ican3: fix support for older hardware revisions
  net: do not disable sg for packets requiring no checksum
  aoe: assert AoE packets marked as requiring no checksum
  at91ether: return PTR_ERR if call to clk_get fails
  xfrm_user: don't copy esn replay window twice for new states
  xfrm_user: ensure user supplied esn replay window is valid
  xfrm_user: fix info leak in copy_to_user_tmpl()
  xfrm_user: fix info leak in copy_to_user_policy()
  xfrm_user: fix info leak in copy_to_user_state()
  xfrm_user: fix info leak in copy_to_user_auth()
  net: qmi_wwan: adding Huawei E367, ZTE MF683 and Pantech P4200
  tcp: restore rcv_wscale in a repair mode (v2)
  ...
2012-09-21 14:32:55 -07:00
Linus Torvalds
6219844e72 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc updates from David Miller:

1) Debugging builds on 32-bit sparc need to handle the R_SPARC_DISP32
   relocation, not just 64-bit sparc.  From Andreas Larsson.

2) Wei Yongjun noticed that module_alloc() on sparc can return an
   error pointer, but that's not allowed.  module_alloc() should
   return only a valid pointer, or NULL.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: fix the return value of module_alloc()
  sparc32: Enable the relocation target R_SPARC_DISP32 for sparc32
2012-09-21 14:31:50 -07:00
Linus Torvalds
9d10890792 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Small fixlets"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/init.c: Fix devmem_is_allowed() off by one
  x86/kconfig: Remove outdated reference to Intel CPUs in CONFIG_SWIOTLB
2012-09-21 14:26:23 -07:00
Linus Torvalds
519b3b742d Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Ingo Molnar:
 "One more timekeeping fix for v3.6"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Fix timeekeping_get_ns overflow on 32bit systems
2012-09-21 14:25:46 -07:00
Linus Torvalds
18f5600ba2 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Small perf fixlets"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tracing: Don't call page_to_pfn() if page is NULL
  perf/x86: Fix Intel Ivy Bridge support
  perf/x86/ibs: Check syscall attribute flags
  perf/x86: Export Sandy Bridge uncore clockticks event in sysfs
2012-09-21 14:24:48 -07:00
Linus Torvalds
789f95b788 xfs: bugfixes for 3.6-rc7
- fix a regression related to xfs_sync_worker racing with unmount.
 - fix a race while discarding xfs buffers.
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Merge tag 'for-linus-v3.6-rc7' of git://oss.sgi.com/xfs/xfs

Pull xfs bugfixes from Ben Myers:
 - fix a regression related to xfs_sync_worker racing with unmount.
 - fix a race while discarding xfs buffers.

* tag 'for-linus-v3.6-rc7' of git://oss.sgi.com/xfs/xfs:
  xfs: stop the sync worker before xfs_unmountfs
  xfs: fix race while discarding buffers [V4]
2012-09-21 12:43:01 -07:00
Linus Torvalds
36a21fe639 Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
 "Fixes for big 3 drivers:

  nouveau: revert earlier MBP fix, put a dmi based MBP fix in its place
  (fixes a regression we found on some Dell eDP panels doing some
  internal testing)

  radeon: revert pll fixes, real fix is too invasive, fix scratch leak

  intel: 3 minor fixes, one for HDMI audio."

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/nouveau: add dmi quirk for gpio reset
  drm/radeon: Prevent leak of scratch register on resume from suspend
  Revert "drm/nv50-/gpio: initialise to vbios defaults during init"
  Revert "drm/radeon: rework pll selection (v3)"
  drm/i915: HDMI - Clear Audio Enable bit for Hot Plug
  drm/i915: Reduce a pin-leak BUG into a WARN
  drm/i915: enable lvds pin pairs before dpll on gen2
2012-09-21 12:41:28 -07:00
Linus Torvalds
6551d6fe21 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:
 "Updates for the input subsystem.  Just a few driver updates mostly
  dealing with recent regressions."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: edt-ft5x06 - return -EFAULT on copy_to_user() error
  Input: sentelic - filter out erratic movement when lifting finger
  Input: ambakmi - [un]prepare clocks when enabling amd disabling
  Input: i8042 - disable mux on Toshiba C850D
  Revert "input: ab8500-ponkey: Create AB8500 domain IRQ mapping"
  Input: imx_keypad - fix missing clk conversions
  Input: usbtouchscreen - initialize eGalax devices
2012-09-21 12:39:28 -07:00
Linus Torvalds
868f480bed Merge git://www.linux-watchdog.org/linux-watchdog
Pull watchdog fixes from Wim Van Sebroeck:
 "Fix a kdump issue in hpwdt and a possible NULL dereference."

* git://www.linux-watchdog.org/linux-watchdog:
  watchdog: move the dereference below the NULL test
  hpwdt: Fix kdump issue in hpwdt
2012-09-21 12:36:23 -07:00
Linus Torvalds
6d77987fe6 Add missing 'name' sysfs attributes to ad7314 and ads7871 drivers
Bump maximum wait time for applesmc driver (again)
 Fix build warning seen with W=1 in include/linux/kernel.h, introduced
 with b6d86d3 (Fix DIV_ROUND_CLOSEST to support negative dividends)
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Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:
 - Add missing 'name' sysfs attributes to ad7314 and ads7871 drivers
 - Bump maximum wait time for applesmc driver (again)
 - Fix build warning seen with W=1 in include/linux/kernel.h, introduced
   with commit b6d86d3d6d ("Fix DIV_ROUND_CLOSEST to support negative
   dividends")

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  linux/kernel.h: Fix warning seen with W=1 due to change in DIV_ROUND_CLOSEST
  hwmon: (applesmc) Bump max wait
  hwmon: (ad7314) Add 'name' sysfs attribute
  hwmon: (ads7871) Add 'name' sysfs attribute
2012-09-21 12:33:31 -07:00
Linus Torvalds
06b050eb81 Merge branch 'fixes' of git://git.infradead.org/users/vkoul/slave-dma
Pull slave-dmaengine fixes from Vinod Koul:
 "There are two trivial fixes in pl330 driver and two in at_hdmac
  driver."

* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
  DMA: PL330: Check the pointer returned by kzalloc
  DMA: PL330: Fix potential NULL pointer dereference in pl330_submit_req()
  dmaengine: at_hdmac: check that each sg data length is non-null
  dmaengine: at_hdmac: fix comment in atc_prep_slave_sg()
2012-09-21 12:15:37 -07:00
Linus Torvalds
633650132e arm-soc: bug fixes for v3.6-rc
A couple of samsung clock locking fixes, at91 device tree gpio
 configuration fix and a couple more for shmobile and i.MX.
 
 All small targeted fixes.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull arm-soc bug fixes from Olof Johansson:
 "A couple of samsung clock locking fixes, at91 device tree gpio
  configuration fix and a couple more for shmobile and i.MX.

  All small targeted fixes."

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM i.MX25: Make timer irq work again
  ARM: imx: armadillo5x0: Fix illegal register access
  ARM: shmobile: kzm9g: bugfix: correct mmcif interrupt settings
  ARM: SAMSUNG: Use spin_lock_{irqsave,irqrestore} in clk_set_rate
  ARM: at91: fix missing #interrupt-cells on gpio-controller
  ARM: SAMSUNG: use spin_lock_irqsave() in clk_set_parent
2012-09-21 12:14:47 -07:00
Wei Yongjun
a9e8d1a6b8 sparc: fix the return value of module_alloc()
In case of error, function module_alloc() in other platform never
returns ERR_PTR(), and all of the user only check for NULL, so
we'd better return NULL instead of ERR_PTR().

dpatch engine is used to auto generated this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-21 12:14:20 -07:00
Andreas Larsson
dfa520af2c sparc32: Enable the relocation target R_SPARC_DISP32 for sparc32
GNU Binutils 2.20.1 generates .eh_frame sections that uses R_SPARC_DISP32.

Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-21 12:14:19 -07:00
Linus Torvalds
267b50fe6f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Martin Schwidefsky:
 "Bug fixes for 3.6-rc7, including some important patches for large page
  related memory management issues."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/dasd: fix read unit address configuration loop
  s390/dasd: fix pathgroup race
  s390/mm: fix user access page-table walk code
  s390/hwcaps: do not report high gprs for 31 bit kernel
  s390/cio: invalidate cdev pointer before deregistration
  s390/cio: fix IO subchannel event race
  s390/dasd: move wake_up call
  s390/hugetlb: use direct TLB flushing for hugetlbfs pages
  s390/mm: fix deadlock in unmap_hugepage_range()
2012-09-21 12:10:17 -07:00
Linus Torvalds
8ca7de9164 Bug-fixes:
* Fix M2P batching re-using the incorrect structure field.
  * Disable BIOS SMP MP table search.
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Merge tag 'stable/for-linus-3.6-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
 - Fix M2P batching re-using the incorrect structure field.

   In v3.5 we added batching for M2P override (Machine Frame Number ->
   Physical Frame Number), but the original MFN was saved in an
   incorrect structure - and we would oops/restore when restoring with
   the old MFN.

 - Disable BIOS SMP MP table search.

   A bootup issue that we had ignored until we found that on DL380 G6 it
   was needed.

* tag 'stable/for-linus-3.6-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/boot: Disable BIOS SMP MP table search.
  xen/m2p: do not reuse kmap_op->dev_bus_addr
2012-09-21 12:06:54 -07:00
Stefan Roese
a630844d89 net/stmmac: Use clk_prepare_enable and clk_disable_unprepare
This patch fixes an issue introduced by commit ID 6a81c26f
[net/stmmac: remove conditional compilation of clk code], which
switched from the internal stmmac_clk_{en}{dis}able calls to
clk_{en}{dis}able. By this, calling clk_prepare and clk_unprepare
was removed.

clk_{un}prepare is mandatory for platforms using common clock framework.
Since these drivers are used by SPEAr platform, which supports common
clock framework, add clk_{un}prepare() support for them. Otherwise
the clocks are not correctly en-/disabled and ethernet support doesn't
work.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-21 14:59:52 -04:00
Linus Torvalds
e05e279e6f debugfs: fix u32_array race in format_array_alloc
The format_array_alloc() function is fundamentally racy, in that it
prints the array twice: once to figure out how much space to allocate
for the buffer, and the second time to actually print out the data.

If any of the array contents changes in between, the allocation size may
be wrong, and the end result may be truncated in odd ways.

Just don't do it.  Allocate a maximum-sized array up-front, and just
format the array contents once.  The only user of the u32_array
interfaces is the Xen spinlock statistics code, and it has 31 entries in
the arrays, so the maximum size really isn't that big, and the end
result is much simpler code without the bug.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 11:48:05 -07:00