Commit graph

20688 commits

Author SHA1 Message Date
Paul E. McKenney 7fd0ddc5bf rcu: Fix synchronize_sched_expedited() type error for "s"
The type of "s" has been "long" rather than the correct "unsigned long"
for quite some time.  This commit fixes this type error.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:55 -07:00
Paul E. McKenney b09e5f8601 rcu: Abstract funnel locking from synchronize_sched_expedited()
This commit abstracts funnel locking from synchronize_sched_expedited()
so that it may be used by synchronize_rcu_expedited().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:53 -07:00
Paul E. McKenney 543c6158f6 rcu: Make synchronize_rcu_expedited() use sequence-counter scheme
Although synchronize_rcu_expedited() uses a sequence-counter scheme, it
is based on a single increment per grace period, which means that tasks
piggybacking off of concurrent grace periods may be forced to wait longer
than necessary.  This commit therefore applies the new sequence-count
functions developed for synchronize_sched_expedited() to speed things
up a bit and to consolidate the sequence-counter implementation.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:52 -07:00
Paul E. McKenney 28f00767e3 rcu: Abstract sequence counting from synchronize_sched_expedited()
This commit creates rcu_exp_gp_seq_start() and rcu_exp_gp_seq_end() to
bracket an expedited grace period, rcu_exp_gp_seq_snap() to snapshot the
sequence counter, and rcu_exp_gp_seq_done() to check to see if a full
expedited grace period has elapsed since the snapshot.  These will be
applied to synchronize_rcu_expedited().  These are defined in terms of
underlying rcu_seq_start(), rcu_seq_end(), rcu_seq_snap(), rcu_seq_done(),
which will be applied to _rcu_barrier().

One reason that this commit doesn't use the seqcount primitives themselves
is that the smp_wmb() in those primitive is insufficient due to the fact
that expedited grace periods do reads as well as writes.  In addition,
the read-side seqcount primitives detect a potentially partial change,
where the expedited primitives instead need a guaranteed full change.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:51 -07:00
Peter Zijlstra 3a6d7c64d7 rcu: Make expedited GP CPU stoppage asynchronous
Sequentially stopping the CPUs slows down expedited grace periods by
at least a factor of two, based on rcutorture's grace-period-per-second
rate.  This is a conservative measure because rcutorture uses unusually
long RCU read-side critical sections and because rcutorture periodically
quiesces the system in order to test RCU's ability to ramp down to and
up from the idle state.  This commit therefore replaces the stop_one_cpu()
with stop_one_cpu_nowait(), using an atomic-counter scheme to determine
when all CPUs have passed through the stopped state.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:50 -07:00
Paul E. McKenney 385b73c06f rcu: Get rid of synchronize_sched_expedited()'s polling loop
This commit gets rid of synchronize_sched_expedited()'s mutex_trylock()
polling loop in favor of a funnel-locking scheme based on the rcu_node
tree.  The work-done check is done at each level of the tree, allowing
high-contention situations to be resolved quickly with reasonable levels
of mutex contention.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:48 -07:00
Paul E. McKenney d6ada2cf2f rcu: Rework synchronize_sched_expedited() counter handling
Now that synchronize_sched_expedited() have a mutex, it can use simpler
work-already-done detection scheme.  This commit simplifies this scheme
by using something similar to the sequence-locking counter scheme.
A counter is incremented before and after each grace period, so that
the counter is odd in the midst of the grace period and even otherwise.
So if the counter has advanced to the second even number that is
greater than or equal to the snapshot, the required grace period has
already happened.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:47 -07:00
Peter Zijlstra c190c3b16c rcu: Switch synchronize_sched_expedited() to stop_one_cpu()
The synchronize_sched_expedited() currently invokes try_stop_cpus(),
which schedules the stopper kthreads on each online non-idle CPU,
and waits until all those kthreads are running before letting any
of them stop.  This is disastrous for real-time workloads, which
get hit with a preemption that is as long as the longest scheduling
latency on any CPU, including any non-realtime housekeeping CPUs.
This commit therefore switches to using stop_one_cpu() on each CPU
in turn.  This avoids inflicting the worst-case scheduling latency
on the worst-case CPU onto all other CPUs, and also simplifies the
code a little bit.

Follow-up commits will simplify the counter-snapshotting algorithm
and convert a number of the counters that are now protected by the
new ->expedited_mutex to non-atomic.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
[ paulmck: Kept stop_one_cpu(), dropped disabling of "guardrails". ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:45 -07:00
Paul E. McKenney 75c27f119b rcu: Remove CONFIG_RCU_CPU_STALL_INFO
The CONFIG_RCU_CPU_STALL_INFO has been default-y for a couple of
releases with no complaints, so it is time to eliminate this Kconfig
option entirely, so that the long-form RCU CPU stall warnings cannot
be disabled.  This commit does just that.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:44 -07:00
Paul E. McKenney 9b68387450 rcu: Stop disabling CPU hotplug in synchronize_rcu_expedited()
The fact that tasks could be migrated from leaf to root rcu_node
structures meant that synchronize_rcu_expedited() had to disable
CPU hotplug.  However, tasks now stay put, so this commit removes the
CPU-hotplug disabling from synchronize_rcu_expedited().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:42 -07:00
Paul E. McKenney 13bd64947f rcu: Reset rcu_fanout_leaf if out of bounds
Currently if the rcu_fanout_leaf boot parameter is out of bounds (that
is, less than RCU_FANOUT_LEAF or greater than the number of bits in an
unsigned long), a warning is issued and execution continues with the
out-of-bounds value.  This can result in all manner of failures, so this
patch resets rcu_fanout_leaf to RCU_FANOUT_LEAF when an out-of-bounds
condition is detected.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:41 -07:00
Alexander Gordeev 032dfc8722 rcu: Shut up bogus gcc array bounds warning
Because gcc does not realize a loop would not be entered ever
(i.e. in case of rcu_num_lvls == 1):

  for (i = 1; i < rcu_num_lvls; i++)
	  rsp->level[i] = rsp->level[i - 1] + levelcnt[i - 1];

some compiler (pre- 5.x?) versions give a bogus warning:

  kernel/rcu/tree.c: In function ‘rcu_init_one.isra.55’:
  kernel/rcu/tree.c:4108:13: warning: array subscript is above array bounds [-Warray-bounds]
     rsp->level[i] = rsp->level[i - 1] + rsp->levelcnt[i - 1];
               ^
Fix that warning by adding an extra item to rcu_state::level[]
array. Once the bogus warning is fixed in gcc and kernel drops
support of older versions, the dummy item may be removed from
the array.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Suggested-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-17 14:58:40 -07:00
Alexander Gordeev 426216970e rcu: Simplify arithmetic to calculate number of RCU nodes
This update makes arithmetic to calculate number of RCU nodes
more straight and easy to read.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:21 -07:00
Alexander Gordeev cb00710239 rcu: Limit count of static data to the number of RCU levels
Although a number of RCU levels may be less than the current
maximum of four, some static data associated with each level
are allocated for all four levels. As result, the extra data
never get accessed and just wast memory. This update limits
count of allocated items to the number of used RCU levels.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:20 -07:00
Alexander Gordeev 199977bff9 rcu: Remove unnecessary fields from rcu_state structure
Members rcu_state::levelcnt[] and rcu_state::levelspread[]
are only used at init. There is no reason to keep them
afterwards.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:19 -07:00
Alexander Gordeev 05b84aec46 rcu: Limit rcu_capacity[] size to RCU_NUM_LVLS items
Number of items in rcu_capacity[] array is defined by macro
MAX_RCU_LVLS. However, that array is never accessed beyond
RCU_NUM_LVLS index. Therefore, we can limit the array to
RCU_NUM_LVLS items and eliminate MAX_RCU_LVLS. As result,
in most cases the memory is conserved.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:18 -07:00
Alexander Gordeev a6d77081e2 rcu: Limit rcu_state::levelcnt[] to RCU_NUM_LVLS items
Variable rcu_num_lvls is limited by RCU_NUM_LVLS macro.
In turn, rcu_state::levelcnt[] array is never accessed
beyond rcu_num_lvls. Thus, rcu_state::levelcnt[] is safe
to limit to RCU_NUM_LVLS items.

Since rcu_num_lvls could be changed during boot (as result
of rcutree.rcu_fanout_leaf kernel parameter update) one might
assume a new value could overflow the value of RCU_NUM_LVLS.
However, that is not the case, since leaf-level fanout is only
permitted to increase, resulting in rcu_num_lvls possibly to
decrease.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:16 -07:00
Alexander Gordeev 9618138b09 rcu: Simplify rcu_init_geometry() capacity arithmetics
Current code suggests that introducing the extra level to
rcu_capacity[] array makes some of the arithmetic easier.
Well, in fact it appears rather confusing and unnecessary.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:15 -07:00
Alexander Gordeev 679f9858b1 rcu: Cleanup rcu_init_geometry() code and arithmetics
This update simplifies rcu_init_geometry() code flow
and makes calculation of the total number of rcu_node
structures more easy to read.

The update relies on the fact num_rcu_lvl[] is never
accessed beyond rcu_num_lvls index by the rest of the
code. Therefore, there is no need initialize the whole
num_rcu_lvl[].

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:14 -07:00
Alexander Gordeev 372b0ec24f rcu: Remove superfluous local variable in rcu_init_geometry()
Local variable 'n' mimics 'nr_cpu_ids' while the both are
used within one function. There is no reason for 'n' to
exist whatsoever.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:13 -07:00
Alexander Gordeev 75cf15a4c0 rcu: Panic if RCU tree can not accommodate all CPUs
Currently a condition when RCU tree is unable to accommodate
the configured number of CPUs is not permitted and causes
a fall back to compile-time values. However, the code has no
means to exceed the RCU tree capacity neither at compile-time
nor in run-time. Therefore, if the condition is met in run-
time then it indicates a serios problem elsewhere and should
be handled with a panic.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:12 -07:00
Paul E. McKenney 319362c90f rcu: Provide more diagnostics for stalled GP kthread
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2015-07-15 14:45:10 -07:00
Linus Torvalds 1dc51b8288 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 "Assorted VFS fixes and related cleanups (IMO the most interesting in
  that part are f_path-related things and Eric's descriptor-related
  stuff).  UFS regression fixes (it got broken last cycle).  9P fixes.
  fs-cache series, DAX patches, Jan's file_remove_suid() work"

[ I'd say this is much more than "fixes and related cleanups".  The
  file_table locking rule change by Eric Dumazet is a rather big and
  fundamental update even if the patch isn't huge.   - Linus ]

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
  9p: cope with bogus responses from server in p9_client_{read,write}
  p9_client_write(): avoid double p9_free_req()
  9p: forgetting to cancel request on interrupted zero-copy RPC
  dax: bdev_direct_access() may sleep
  block: Add support for DAX reads/writes to block devices
  dax: Use copy_from_iter_nocache
  dax: Add block size note to documentation
  fs/file.c: __fget() and dup2() atomicity rules
  fs/file.c: don't acquire files->file_lock in fd_install()
  fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
  vfs: avoid creation of inode number 0 in get_next_ino
  namei: make set_root_rcu() return void
  make simple_positive() public
  ufs: use dir_pages instead of ufs_dir_pages()
  pagemap.h: move dir_pages() over there
  remove the pointless include of lglock.h
  fs: cleanup slight list_entry abuse
  xfs: Correctly lock inode when removing suid and file capabilities
  fs: Call security_ops->inode_killpriv on truncate
  fs: Provide function telling whether file_remove_privs() will do anything
  ...
2015-07-04 19:36:06 -07:00
Linus Torvalds 1b3618b60a Except for the preempt notifiers fix, these are all small bugfixes
that could have been waited for -rc2.  Sending them now since I
 was taking care of Peter's patch anyway.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "Except for the preempt notifiers fix, these are all small bugfixes
  that could have been waited for -rc2.  Sending them now since I was
  taking care of Peter's patch anyway"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm: add hyper-v crash msrs values
  KVM: x86: remove data variable from kvm_get_msr_common
  KVM: s390: virtio-ccw: don't overwrite config space values
  KVM: x86: keep track of LVT0 changes under APICv
  KVM: x86: properly restore LVT0
  KVM: x86: make vapics_in_nmi_mode atomic
  sched, preempt_notifier: separate notifier registration from static_key inc/dec
2015-07-04 11:29:59 -07:00
Linus Torvalds 22a093b2fb Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Debug info and other statistics fixes and related enhancements"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/numa: Fix numa balancing stats in /proc/pid/sched
  sched/numa: Show numa_group ID in /proc/sched_debug task listings
  sched/debug: Move print_cfs_rq() declaration to kernel/sched/sched.h
  sched/stat: Expose /proc/pid/schedstat if CONFIG_SCHED_INFO=y
  sched/stat: Simplify the sched_info accounting dependency
2015-07-04 08:56:53 -07:00
Srikar Dronamraju 397f2378f1 sched/numa: Fix numa balancing stats in /proc/pid/sched
Commit 44dba3d5d6 ("sched: Refactor task_struct to use
numa_faults instead of numa_* pointers") modified the way
tsk->numa_faults stats are accounted.

However that commit never touched show_numa_stats() that is displayed
in /proc/pid/sched and thus the numbers displayed in /proc/pid/sched
don't match the actual numbers.

Fix it by making sure that /proc/pid/sched reflects the task
fault numbers. Also add group fault stats too.

Also couple of more modifications are added here:

1. Format changes:

  - Previously we would list two entries per node, one for private
    and one for shared. Also the home node info was listed in each entry.

  - Now preferred node, total_faults and current node are
    displayed separately.

  - Now there is one entry per node, that lists private,shared task and
    group faults.

2. Unit changes:

  - p->numa_pages_migrated was getting reset after every read of
    /proc/pid/sched. It's more useful to have absolute numbers since
    differential migrations between two accesses can be more easily
    calculated.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Iulia Manda <iulia.manda21@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1435252903-1081-4-git-send-email-srikar@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-04 10:04:33 +02:00
Srikar Dronamraju e3d24d0a60 sched/numa: Show numa_group ID in /proc/sched_debug task listings
Having the numa group ID in /proc/sched_debug helps to see how
the numa groups have spread across the system.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Iulia Manda <iulia.manda21@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1435252903-1081-3-git-send-email-srikar@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-04 10:04:32 +02:00
Srikar Dronamraju 6b55c9654f sched/debug: Move print_cfs_rq() declaration to kernel/sched/sched.h
Currently print_cfs_rq() is declared in include/linux/sched.h.
However it's not used outside kernel/sched. Hence move the
declaration to kernel/sched/sched.h

Also some functions are only available for CONFIG_SCHED_DEBUG=y.
Hence move the declarations to within the #ifdef.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Iulia Manda <iulia.manda21@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1435252903-1081-2-git-send-email-srikar@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-04 10:04:31 +02:00
Naveen N. Rao f6db834799 sched/stat: Simplify the sched_info accounting dependency
Both CONFIG_SCHEDSTATS=y and CONFIG_TASK_DELAY_ACCT=y track task
sched_info, which results in ugly #if clauses.

Simplify the code by introducing a synthethic CONFIG_SCHED_INFO
switch, selected by both.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: a.p.zijlstra@chello.nl
Cc: ricklind@us.ibm.com
Link: http://lkml.kernel.org/r/8d19eef800811a94b0f91bcbeb27430a884d7433.1435255405.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-04 10:04:30 +02:00
Linus Torvalds 0cbee99269 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace updates from Eric Biederman:
 "Long ago and far away when user namespaces where young it was realized
  that allowing fresh mounts of proc and sysfs with only user namespace
  permissions could violate the basic rule that only root gets to decide
  if proc or sysfs should be mounted at all.

  Some hacks were put in place to reduce the worst of the damage could
  be done, and the common sense rule was adopted that fresh mounts of
  proc and sysfs should allow no more than bind mounts of proc and
  sysfs.  Unfortunately that rule has not been fully enforced.

  There are two kinds of gaps in that enforcement.  Only filesystems
  mounted on empty directories of proc and sysfs should be ignored but
  the test for empty directories was insufficient.  So in my tree
  directories on proc, sysctl and sysfs that will always be empty are
  created specially.  Every other technique is imperfect as an ordinary
  directory can have entries added even after a readdir returns and
  shows that the directory is empty.  Special creation of directories
  for mount points makes the code in the kernel a smidge clearer about
  it's purpose.  I asked container developers from the various container
  projects to help test this and no holes were found in the set of mount
  points on proc and sysfs that are created specially.

  This set of changes also starts enforcing the mount flags of fresh
  mounts of proc and sysfs are consistent with the existing mount of
  proc and sysfs.  I expected this to be the boring part of the work but
  unfortunately unprivileged userspace winds up mounting fresh copies of
  proc and sysfs with noexec and nosuid clear when root set those flags
  on the previous mount of proc and sysfs.  So for now only the atime,
  read-only and nodev attributes which userspace happens to keep
  consistent are enforced.  Dealing with the noexec and nosuid
  attributes remains for another time.

  This set of changes also addresses an issue with how open file
  descriptors from /proc/<pid>/ns/* are displayed.  Recently readlink of
  /proc/<pid>/fd has been triggering a WARN_ON that has not been
  meaningful since it was added (as all of the code in the kernel was
  converted) and is not now actively wrong.

  There is also a short list of issues that have not been fixed yet that
  I will mention briefly.

  It is possible to rename a directory from below to above a bind mount.
  At which point any directory pointers below the renamed directory can
  be walked up to the root directory of the filesystem.  With user
  namespaces enabled a bind mount of the bind mount can be created
  allowing the user to pick a directory whose children they can rename
  to outside of the bind mount.  This is challenging to fix and doubly
  so because all obvious solutions must touch code that is in the
  performance part of pathname resolution.

  As mentioned above there is also a question of how to ensure that
  developers by accident or with purpose do not introduce exectuable
  files on sysfs and proc and in doing so introduce security regressions
  in the current userspace that will not be immediately obvious and as
  such are likely to require breaking userspace in painful ways once
  they are recognized"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  vfs: Remove incorrect debugging WARN in prepend_path
  mnt: Update fs_fully_visible to test for permanently empty directories
  sysfs: Create mountpoints with sysfs_create_mount_point
  sysfs: Add support for permanently empty directories to serve as mount points.
  kernfs: Add support for always empty directories.
  proc: Allow creating permanently empty directories that serve as mount points
  sysctl: Allow creating permanently empty directories that serve as mountpoints.
  fs: Add helper functions for permanently empty directories.
  vfs: Ignore unlocked mounts in fs_fully_visible
  mnt: Modify fs_fully_visible to deal with locked ro nodev and atime
  mnt: Refactor the logic for mounting sysfs and proc in a user namespace
2015-07-03 15:20:57 -07:00
Peter Zijlstra 2ecd9d29ab sched, preempt_notifier: separate notifier registration from static_key inc/dec
Commit 1cde2930e1 ("sched/preempt: Add static_key() to preempt_notifiers")
had two problems.  First, the preempt-notifier API needs to sleep with the
addition of the static_key, we do however need to hold off preemption
while modifying the preempt notifier list, otherwise a preemption could
observe an inconsistent list state.  KVM correctly registers and
unregisters preempt notifiers with preemption disabled, so the sleep
caused dmesg splats.

Second, KVM registers and unregisters preemption notifiers very often
(in vcpu_load/vcpu_put).  With a single uniprocessor guest the static key
would move between 0 and 1 continuously, hitting the slow path on every
userspace exit.

To fix this, wrap the static_key inc/dec in a new API, and call it from
KVM.

Fixes: 1cde2930e1 ("sched/preempt: Add static_key() to preempt_notifiers")
Reported-by: Pontus Fuchs <pontus.fuchs@gmail.com>
Reported-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-03 18:55:00 +02:00
Linus Torvalds 7df9ab845c make certificate list change message more useful
It's a bug in our Makefile rules, make it show what the changing
certificate list was, and make it a warning so that people actually see
it.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-02 16:42:13 -07:00
Linus Torvalds 2d01eedf1d Merge branch 'akpm' (patches from Andrew)
Merge third patchbomb from Andrew Morton:

 - the rest of MM

 - scripts/gdb updates

 - ipc/ updates

 - lib/ updates

 - MAINTAINERS updates

 - various other misc things

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (67 commits)
  genalloc: rename of_get_named_gen_pool() to of_gen_pool_get()
  genalloc: rename dev_get_gen_pool() to gen_pool_get()
  x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit
  MAINTAINERS: add zpool
  MAINTAINERS: BCACHE: Kent Overstreet has changed email address
  MAINTAINERS: move Jens Osterkamp to CREDITS
  MAINTAINERS: remove unused nbd.h pattern
  MAINTAINERS: update brcm gpio filename pattern
  MAINTAINERS: update brcm dts pattern
  MAINTAINERS: update sound soc intel patterns
  MAINTAINERS: remove website for paride
  MAINTAINERS: update Emulex ocrdma email addresses
  bcache: use kvfree() in various places
  libcxgbi: use kvfree() in cxgbi_free_big_mem()
  target: use kvfree() in session alloc and free
  IB/ehca: use kvfree() in ipz_queue_{cd}tor()
  drm/nouveau/gem: use kvfree() in u_free()
  drm: use kvfree() in drm_free_large()
  cxgb4: use kvfree() in t4_free_mem()
  cxgb3: use kvfree() in cxgb_free_mem()
  ...
2015-07-01 17:47:51 -07:00
Linus Torvalds 6ac15baacb Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "This contains:

   - a build regression fix introduced by the timeconst move

   - a hotplug regression fix introduced by the timer wheel diet

   - a cpu hotplug bug fix for the exynos clocksource driver"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Remove development rules from Kbuild/Makefile
  timer: Fix hotplug regression
  clocksource: exynos_mct: Avoid blocking calls in the cpu hotplug notifier
2015-07-01 15:44:18 -07:00
Linus Torvalds 5c3950970b Power management and ACPI fixes for v4.2-rc1
- Fix a recently added memory leak in an error path in the ACPI
    resources management code (Dan Carpenter).
 
  - Fix a build warning triggered by an ACPI video header function
    that should be static inline (Borislav Petkov).
 
  - Change names of helper function converting struct fwnode_handle
    pointers to either struct device_node or struct acpi_device
    pointers so they don't conflict with local variable names
    (Alexander Sverdlin).
 
  - Make the hibernate core re-enable nonboot CPUs on failures to
    disable them as expected (Vitaly Kuznetsov).
 
  - Increase the default timeout of the device suspend watchdog to
    prevent it from triggering too early on some systems (Takashi Iwai).
 
  - Prevent the cpuidle powernv driver from registering idle
    states with CPUIDLE_FLAG_TIMER_STOP set if CONFIG_TICK_ONESHOT
    is unset which leads to boot hangs (Preeti U Murthy).
 
 /
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Merge tag 'pm+acpi-4.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI fixes from Rafael Wysocki:
 "These are fixes that didn't make it to the previous PM+ACPI pull
  request or are fixing issues introduced by it.

  Specifics:

   - Fix a recently added memory leak in an error path in the ACPI
     resources management code (Dan Carpenter)

   - Fix a build warning triggered by an ACPI video header function that
     should be static inline (Borislav Petkov)

   - Change names of helper function converting struct fwnode_handle
     pointers to either struct device_node or struct acpi_device
     pointers so they don't conflict with local variable names
     (Alexander Sverdlin)

   - Make the hibernate core re-enable nonboot CPUs on failures to
     disable them as expected (Vitaly Kuznetsov)

   - Increase the default timeout of the device suspend watchdog to
     prevent it from triggering too early on some systems (Takashi Iwai)

   - Prevent the cpuidle powernv driver from registering idle states
     with CPUIDLE_FLAG_TIMER_STOP set if CONFIG_TICK_ONESHOT is unset
     which leads to boot hangs (Preeti U Murthy)"

* tag 'pm+acpi-4.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  tick/idle/powerpc: Do not register idle states with CPUIDLE_FLAG_TIMER_STOP set in periodic mode
  PM / sleep: Increase default DPM watchdog timeout to 60
  PM / hibernate: re-enable nonboot cpus on disable_nonboot_cpus() failure
  ACPI / OF: Rename of_node() and acpi_node() to to_of_node() and to_acpi_node()
  ACPI / video: Inline acpi_video_set_dmi_backlight_type
  ACPI / resources: free memory on error in add_region_before()
2015-07-01 14:17:44 -07:00
Linus Torvalds 7adf12b87f xen: features and cleanups for 4.2-rc0
- Add "make xenconfig" to assist in generating configs for Xen guests.
 - Preparatory cleanups necessary for supporting 64 KiB pages in ARM
   guests.
 - Automatically use hvc0 as the default console in ARM guests.
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Merge tag 'for-linus-4.2-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:
 "Xen features and cleanups for 4.2-rc0:

   - add "make xenconfig" to assist in generating configs for Xen guests

   - preparatory cleanups necessary for supporting 64 KiB pages in ARM
     guests

   - automatically use hvc0 as the default console in ARM guests"

* tag 'for-linus-4.2-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  block/xen-blkback: s/nr_pages/nr_segs/
  block/xen-blkfront: Remove invalid comment
  block/xen-blkfront: Remove unused macro MAXIMUM_OUTSTANDING_BLOCK_REQS
  arm/xen: Drop duplicate define mfn_to_virt
  xen/grant-table: Remove unused macro SPP
  xen/xenbus: client: Fix call of virt_to_mfn in xenbus_grant_ring
  xen: Include xen/page.h rather than asm/xen/page.h
  kconfig: add xenconfig defconfig helper
  kconfig: clarify kvmconfig is for kvm
  xen/pcifront: Remove usage of struct timeval
  xen/tmem: use BUILD_BUG_ON() in favor of BUG_ON()
  hvc_xen: avoid uninitialized variable warning
  xenbus: avoid uninitialized variable warning
  xen/arm: allow console=hvc0 to be omitted for guests
  arm,arm64/xen: move Xen initialization earlier
  arm/xen: Correctly check if the event channel interrupt is present
2015-07-01 11:53:46 -07:00
Linus Torvalds 02201e3f1b Minor merge needed, due to function move.
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
 speed module address lookup.  He found some abusers of the module lock
 doing that too.
 
 A little bit of parameter work here too; including Dan Streetman's breaking
 up the big param mutex so writing a parameter can load another module (yeah,
 really).  Unfortunately that broke the usual suspects, !CONFIG_MODULES and
 !CONFIG_SYSFS, so those fixes were appended too.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Main excitement here is Peter Zijlstra's lockless rbtree optimization
  to speed module address lookup.  He found some abusers of the module
  lock doing that too.

  A little bit of parameter work here too; including Dan Streetman's
  breaking up the big param mutex so writing a parameter can load
  another module (yeah, really).  Unfortunately that broke the usual
  suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
  appended too"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
  modules: only use mod->param_lock if CONFIG_MODULES
  param: fix module param locks when !CONFIG_SYSFS.
  rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
  module: add per-module param_lock
  module: make perm const
  params: suppress unused variable error, warn once just in case code changes.
  modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
  kernel/module.c: avoid ifdefs for sig_enforce declaration
  kernel/workqueue.c: remove ifdefs over wq_power_efficient
  kernel/params.c: export param_ops_bool_enable_only
  kernel/params.c: generalize bool_enable_only
  kernel/module.c: use generic module param operaters for sig_enforce
  kernel/params: constify struct kernel_param_ops uses
  sysfs: tightened sysfs permission checks
  module: Rework module_addr_{min,max}
  module: Use __module_address() for module_address_lookup()
  module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
  module: Optimize __module_address() using a latched RB-tree
  rbtree: Implement generic latch_tree
  seqlock: Introduce raw_read_seqcount_latch()
  ...
2015-07-01 10:49:25 -07:00
Eric W. Biederman f9bb48825a sysfs: Create mountpoints with sysfs_create_mount_point
This allows for better documentation in the code and
it allows for a simpler and fully correct version of
fs_fully_visible to be written.

The mount points converted and their filesystems are:
/sys/hypervisor/s390/       s390_hypfs
/sys/kernel/config/         configfs
/sys/kernel/debug/          debugfs
/sys/firmware/efi/efivars/  efivarfs
/sys/fs/fuse/connections/   fusectl
/sys/fs/pstore/             pstore
/sys/kernel/tracing/        tracefs
/sys/fs/cgroup/             cgroup
/sys/kernel/security/       securityfs
/sys/fs/selinux/            selinuxfs
/sys/fs/smackfs/            smackfs

Cc: stable@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:47 -05:00
Eric W. Biederman f9bd6733d3 sysctl: Allow creating permanently empty directories that serve as mountpoints.
Add a magic sysctl table sysctl_mount_point that when used to
create a directory forces that directory to be permanently empty.

Update the code to use make_empty_dir_inode when accessing permanently
empty directories.

Update the code to not allow adding to permanently empty directories.

Update /proc/sys/fs/binfmt_misc to be a permanently empty directory.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:39 -05:00
Thomas Gleixner 65f26062cd time: Remove development rules from Kbuild/Makefile
time.o gets rebuilt unconditionally due to a leftover Makefile rule
which was placed there for development purposes.

Remove it along with the commented out always rule in the toplevel
Kbuild file.

Fixes: 0a227985d4 'time: Move timeconst.h into include/generated'
Reported-by; Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Nicholas Mc Guire <der.herr@hofr.at>
2015-07-01 09:57:35 +02:00
Pekka Enberg 200f1ce365 kernel/relay.c: use kvfree() in relay_free_page_array()
Use kvfree() instead of open-coding it.

Signed-off-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:44:59 -07:00
Antonio Ospite b389645f04 printk: improve the description of /dev/kmsg line format
The comment about /dev/kmsg does not mention the additional values which
may actually be exported, fix that.

Also move up the part of the comment instructing the users to ignore these
additional values, this way the reading is more fluent and logically
compact.

Signed-off-by: Antonio Ospite <ao2@ao2.it>
Cc: Joe Perches <joe@perches.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:44:59 -07:00
Lorenzo Stoakes 3e44c471a2 gcov: add support for GCC 5.1
Fix kernel gcov support for GCC 5.1.  Similar to commit a992bf836f
("gcov: add support for GCC 4.9"), this patch takes into account the
existence of a new gcov counter (see gcc's gcc/gcov-counter.def.)

Firstly, it increments GCOV_COUNTERS (to 10), which makes the data
structure struct gcov_info compatible with GCC 5.1.

Secondly, a corresponding counter function __gcov_merge_icall_topn (Top N
value tracking for indirect calls) is included in base.c with the other
gcov counters unused for kernel profiling.

Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Yuan Pengfei <coolypf@qq.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:44:57 -07:00
HATAYAMA Daisuke 5375b708f2 kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops path
Commit f06e5153f4 ("kernel/panic.c: add "crash_kexec_post_notifiers"
option for kdump after panic_notifers") introduced
"crash_kexec_post_notifiers" kernel boot option, which toggles wheather
panic() calls crash_kexec() before panic_notifiers and dump kmsg or after.

The problem is that the commit overlooks panic_on_oops kernel boot option.
 If it is enabled, crash_kexec() is called directly without going through
panic() in oops path.

To fix this issue, this patch adds a check to "crash_kexec_post_notifiers"
in the condition of kexec_should_crash().

Also, put a comment in kexec_should_crash() to explain not obvious things
on this patch.

Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Acked-by: Baoquan He <bhe@redhat.com>
Tested-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:44:57 -07:00
HATAYAMA Daisuke f45d85ff1f kernel/panic: call the 2nd crash_kexec() only if crash_kexec_post_notifiers is enabled
For compatibility with the behaviour before the commit f06e5153f4
("kernel/panic.c: add "crash_kexec_post_notifiers" option for kdump after
panic_notifers"), the 2nd crash_kexec() should be called only if
crash_kexec_post_notifiers is enabled.

Note that crash_kexec() returns immediately if kdump crash kernel is not
loaded, so in this case, this patch makes no functionality change, but the
point is to make it explicit, from the caller panic() side, that the 2nd
crash_kexec() does nothing.

Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Suggested-by: Ingo Molnar <mingo@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:44:57 -07:00
Stephen Rothwell 20bdc2cfdb modules: only use mod->param_lock if CONFIG_MODULES
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-06-28 14:50:12 +09:30
Rusty Russell cf2fde7b39 param: fix module param locks when !CONFIG_SYSFS.
As Dan Streetman points out, the entire point of locking for is to
stop sysfs accesses, so they're elided entirely in the !SYSFS case.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-06-28 14:46:14 +09:30
Linus Torvalds 4a10a91756 Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore:
 "Four small audit patches for v4.2, all bug fixes.  Only 10 lines of
  change this time so very unremarkable, the patch subject lines pretty
  much tell the whole story"

* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
  audit: Fix check of return value of strnlen_user()
  audit: obsolete audit_context check is removed in audit_filter_rules()
  audit: fix for typo in comment to function audit_log_link_denied()
  lsm: rename duplicate labels in LSM_AUDIT_DATA_TASK audit message type
2015-06-27 13:53:16 -07:00
Linus Torvalds e22619a29f Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "The main change in this kernel is Casey's generalized LSM stacking
  work, which removes the hard-coding of Capabilities and Yama stacking,
  allowing multiple arbitrary "small" LSMs to be stacked with a default
  monolithic module (e.g.  SELinux, Smack, AppArmor).

  See
        https://lwn.net/Articles/636056/

  This will allow smaller, simpler LSMs to be incorporated into the
  mainline kernel and arbitrarily stacked by users.  Also, this is a
  useful cleanup of the LSM code in its own right"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (38 commits)
  tpm, tpm_crb: fix le64_to_cpu conversions in crb_acpi_add()
  vTPM: set virtual device before passing to ibmvtpm_reset_crq
  tpm_ibmvtpm: remove unneccessary message level.
  ima: update builtin policies
  ima: extend "mask" policy matching support
  ima: add support for new "euid" policy condition
  ima: fix ima_show_template_data_ascii()
  Smack: freeing an error pointer in smk_write_revoke_subj()
  selinux: fix setting of security labels on NFS
  selinux: Remove unused permission definitions
  selinux: enable genfscon labeling for sysfs and pstore files
  selinux: enable per-file labeling for debugfs files.
  selinux: update netlink socket classes
  signals: don't abuse __flush_signals() in selinux_bprm_committed_creds()
  selinux: Print 'sclass' as string when unrecognized netlink message occurs
  Smack: allow multiple labels in onlycap
  Smack: fix seq operations in smackfs
  ima: pass iint to ima_add_violation()
  ima: wrap event related data to the new ima_event_data structure
  integrity: add validity checks for 'path' parameter
  ...
2015-06-27 13:26:03 -07:00
Linus Torvalds e0dd880a54 Merge branch 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue updates from Tejun Heo:
 "Most of the changes are around implementing and fixing fallouts from
  sysfs and internal interface to limit the CPUs available to all
  unbound workqueues to help isolating CPUs.  It needs more work as
  ordered workqueues can roam unrestricted but still is a significant
  improvement"

* 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix typos in comments
  workqueue: move flush_scheduled_work() to workqueue.h
  workqueue: remove the lock from wq_sysfs_prep_attrs()
  workqueue: remove the declaration of copy_workqueue_attrs()
  workqueue: ensure attrs changes are properly synchronized
  workqueue: separate out and refactor the locking of applying attrs
  workqueue: simplify wq_update_unbound_numa()
  workqueue: wq_pool_mutex protects the attrs-installation
  workqueue: fix a typo
  workqueue: function name in the comment differs from the real function name
  workqueue: fix trivial typo in Documentation/workqueue.txt
  workqueue: Allow modifying low level unbound workqueue cpumask
  workqueue: Create low-level unbound workqueues cpumask
  workqueue: split apply_workqueue_attrs() into 3 stages
2015-06-26 20:12:21 -07:00