Commit Graph

19213 Commits

Author SHA1 Message Date
Ingo Molnar
d360b78f99 Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

 - Streamline RCU's use of per-CPU variables, shifting from "cpu"
   arguments to functions to "this_"-style per-CPU variable accessors.

 - Signal-handling RCU updates.

 - Real-time updates.

 - Torture-test updates.

 - Miscellaneous fixes.

 - Documentation updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-20 08:57:58 +01:00
Linus Torvalds
78646f62db ACPI and power management fixes for 3.18-rc5
- Fix a crash in the suspend-to-idle code path introduced by a
    recent commit that forgot to check a pointer against NULL before
    dereferencing it (Dmitry Eremin-Solenikov).
 
  - Fix a boot crash on Exynos5 introduced by a recent commit making
    that platform use generic Device Tree bindings for power domains
    which exposed a weakness in the generic power domains framework
    leading to that crash (Ulf Hansson).
 
  - Fix a crash during system resume on systems where cpufreq depends
    on Operation Performance Points (OPP) for functionality, but
    CONFIG_OPP is not set.  This leads the cpufreq driver registration
    to fail, but the resume code attempts to restore the pre-suspend
    cpufreq configuration (which does not exist) nevertheless and
    crashes.  From Geert Uytterhoeven.
 
  - Add a new ACPI blacklist entry for Dell Vostro 3546 that has
    problems if it is reported as Windows 8 compatible to the BIOS
    (Adam Lee).
 
  - Fix swapped arguments in an error message in the cpufreq-dt
    driver (Abhilash Kesavan).
 
  - Fix up the prototypes of new callbacks in struct generic_pm_domain
    to make them more useful.  Users of those callbacks will be added
    in 3.19 and it's better for them to be based on the correct struct
    definition in mainline from the start.  From Ulf Hansson and
    Kevin Hilman.
 
 /
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Merge tag 'pm+acpi-3.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael Wysocki:
 "These are three regression fixes, two recent (generic power domains,
  suspend-to-idle) and one older (cpufreq), an ACPI blacklist entry for
  one more machine having problems with Windows 8 compatibility, a minor
  cpufreq driver fix (cpufreq-dt) and a fixup for new callback
  definitions (generic power domains).

  Specifics:

   - Fix a crash in the suspend-to-idle code path introduced by a recent
     commit that forgot to check a pointer against NULL before
     dereferencing it (Dmitry Eremin-Solenikov).

   - Fix a boot crash on Exynos5 introduced by a recent commit making
     that platform use generic Device Tree bindings for power domains
     which exposed a weakness in the generic power domains framework
     leading to that crash (Ulf Hansson).

   - Fix a crash during system resume on systems where cpufreq depends
     on Operation Performance Points (OPP) for functionality, but
     CONFIG_OPP is not set.  This leads the cpufreq driver registration
     to fail, but the resume code attempts to restore the pre-suspend
     cpufreq configuration (which does not exist) nevertheless and
     crashes.  From Geert Uytterhoeven.

   - Add a new ACPI blacklist entry for Dell Vostro 3546 that has
     problems if it is reported as Windows 8 compatible to the BIOS
     (Adam Lee).

   - Fix swapped arguments in an error message in the cpufreq-dt driver
     (Abhilash Kesavan).

   - Fix up the prototypes of new callbacks in struct generic_pm_domain
     to make them more useful.  Users of those callbacks will be added
     in 3.19 and it's better for them to be based on the correct struct
     definition in mainline from the start.  From Ulf Hansson and Kevin
     Hilman"

* tag 'pm+acpi-3.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / Domains: Fix initial default state of the need_restore flag
  PM / sleep: Fix entering suspend-to-IDLE if no freeze_oops is set
  PM / Domains: Change prototype for the attach and detach callbacks
  cpufreq: Avoid crash in resume on SMP without OPP
  cpufreq: cpufreq-dt: Fix arguments in clock failure error message
  ACPI / blacklist: blacklist Win8 OSI for Dell Vostro 3546
2014-11-14 13:38:02 -08:00
Xie XiuQi
bc53a3f46d kernel/panic.c: update comments for print_tainted
Commit 69361eef90 ("panic: add TAINT_SOFTLOCKUP") added the 'L' flag,
but failed to update the comments for print_tainted().  So, update the
comments.

Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-13 16:17:06 -08:00
Paul E. McKenney
9ea6c58856 Merge branches 'torture.2014.11.03a', 'cpu.2014.11.03a', 'doc.2014.11.13a', 'fixes.2014.11.13a', 'signal.2014.10.29a' and 'rt.2014.10.29a' into HEAD
cpu.2014.11.03a: Changes for per-CPU variables.
doc.2014.11.13a: Documentation updates.
fixes.2014.11.13a: Miscellaneous fixes.
signal.2014.10.29a: Signal changes.
rt.2014.10.29a: Real-time changes.
torture.2014.11.03a: torture-test changes.
2014-11-13 10:39:04 -08:00
Paul E. McKenney
60ced4950c rcu: Fix FIXME in rcu_tasks_kthread()
This commit affines rcu_tasks_kthread() to the housekeeping CPUs
in CONFIG_NO_HZ_FULL builds.  This is just a default, so systems
administrators are free to put this kthread somewhere else if they wish.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-11-13 10:35:41 -08:00
Linus Torvalds
911883759f Merge branch 'stable-3.18' of git://git.infradead.org/users/pcmoore/audit
Pull audit fixes from Paul Moore:
 "After he sent the initial audit pull request for 3.18, Eric asked me
  to take over the management of the audit tree, hence this pull request
  to fix a couple of problems with audit.

  As you can see below, the changes are minimal: adding some whitespace
  to a string so userspace parses it correctly, and fixing a problem
  with audit's usage of fsnotify that was causing audit watch rules to
  be lost.  Neither of these patches were very controversial on the
  mailing lists and they fix real problems, getting them into 3.18 would
  be a good thing"

* 'stable-3.18' of git://git.infradead.org/users/pcmoore/audit:
  audit: keep inode pinned
  audit: AUDIT_FEATURE_CHANGE message format missing delimiting space
2014-11-13 09:36:39 -08:00
Miklos Szeredi
799b601451 audit: keep inode pinned
Audit rules disappear when an inode they watch is evicted from the cache.
This is likely not what we want.

The guilty commit is "fsnotify: allow marks to not pin inodes in core",
which didn't take into account that audit_tree adds watches with a zero
mask.

Adding any mask should fix this.

Fixes: 90b1e7a578 ("fsnotify: allow marks to not pin inodes in core")
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org # 2.6.36+
Signed-off-by: Paul Moore <pmoore@redhat.com>
2014-11-11 14:20:22 -05:00
Rabin Vincent
07906da788 tracing: Do not risk busy looping in buffer splice
If the read loop in trace_buffers_splice_read() keeps failing due to
memory allocation failures without reading even a single page then this
function will keep busy looping.

Remove the risk for that by exiting the function if memory allocation
failures are seen.

Link: http://lkml.kernel.org/r/1415309167-2373-2-git-send-email-rabin@rab.in

Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-10 16:47:31 -05:00
Rabin Vincent
e30f53aad2 tracing: Do not busy wait in buffer splice
On a !PREEMPT kernel, attempting to use trace-cmd results in a soft
lockup:

 # trace-cmd record -e raw_syscalls:* -F false
 NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [trace-cmd:61]
 ...
 Call Trace:
  [<ffffffff8105b580>] ? __wake_up_common+0x90/0x90
  [<ffffffff81092e25>] wait_on_pipe+0x35/0x40
  [<ffffffff810936e3>] tracing_buffers_splice_read+0x2e3/0x3c0
  [<ffffffff81093300>] ? tracing_stats_read+0x2a0/0x2a0
  [<ffffffff812d10ab>] ? _raw_spin_unlock+0x2b/0x40
  [<ffffffff810dc87b>] ? do_read_fault+0x21b/0x290
  [<ffffffff810de56a>] ? handle_mm_fault+0x2ba/0xbd0
  [<ffffffff81095c80>] ? trace_event_buffer_lock_reserve+0x40/0x80
  [<ffffffff810951e2>] ? trace_buffer_lock_reserve+0x22/0x60
  [<ffffffff81095c80>] ? trace_event_buffer_lock_reserve+0x40/0x80
  [<ffffffff8112415d>] do_splice_to+0x6d/0x90
  [<ffffffff81126971>] SyS_splice+0x7c1/0x800
  [<ffffffff812d1edd>] tracesys_phase2+0xd3/0xd8

The problem is this: tracing_buffers_splice_read() calls
ring_buffer_wait() to wait for data in the ring buffers.  The buffers
are not empty so ring_buffer_wait() returns immediately.  But
tracing_buffers_splice_read() calls ring_buffer_read_page() with full=1,
meaning it only wants to read a full page.  When the full page is not
available, tracing_buffers_splice_read() tries to wait again with
ring_buffer_wait(), which again returns immediately, and so on.

Fix this by adding a "full" argument to ring_buffer_wait() which will
make ring_buffer_wait() wait until the writer has left the reader's
page, i.e.  until full-page reads will succeed.

Link: http://lkml.kernel.org/r/1415645194-25379-1-git-send-email-rabin@rab.in

Cc: stable@vger.kernel.org # 3.16+
Fixes: b1169cc69b ("tracing: Remove mock up poll wait function")
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-10 16:45:43 -05:00
Dmitry Eremin-Solenikov
403b9636fe PM / sleep: Fix entering suspend-to-IDLE if no freeze_oops is set
If no freeze_ops is set, trying to enter suspend-to-IDLE will cause a
nice oops in platform_suspend_prepare_late(). Add respective checks to
platform_suspend_prepare_late() and platform_resume_early() functions.

Fixes: a8d46b9e4e (ACPI / sleep: Rework the handling of ACPI GPE wakeup ...)
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-08 22:30:05 +01:00
Paul E. McKenney
b8969d1a50 rcutorture: Fix rcu_torture_cbflood() memory leak
Commit 38706bc5a2 (rcutorture: Add callback-flood test) vmalloc()ed
a bunch of RCU callbacks, but failed to free them.  This commit fixes
that oversight.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:26:41 -08:00
Pranith Kumar
aa23c6fbc5 rcutorture: Add early boot self tests
Add early boot self tests for RCU under CONFIG_PROVE_RCU.

Currently the only test is adding a dummy callback which increments a counter
which we then later verify after calling rcu_barrier*().

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-11-03 19:26:37 -08:00
Paul E. McKenney
62db99f478 cpu: Avoid puts_pending overflow
A long string of get_online_cpus() with each followed by a
put_online_cpu() that fails to acquire cpu_hotplug.lock can result in
overflow of the cpu_hotplug.puts_pending counter.  Although this is
perhaps improbably, a system with absolutely no CPU-hotplug operations
will have an arbitrarily long time in which this overflow could occur.
This commit therefore adds overflow checks to get_online_cpus() and
try_get_online_cpus().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:21:01 -08:00
Paul E. McKenney
8fa7845df5 rcu: Remove "cpu" argument to rcu_cleanup_after_idle()
The "cpu" argument to rcu_cleanup_after_idle() is always the current
CPU, so drop it.  This moves the smp_processor_id() from the caller to
rcu_cleanup_after_idle(), saving argument-passing overhead.  Again,
the anticipated cross-CPU uses of these functions has been replaced
by NO_HZ_FULL.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:20:56 -08:00
Paul E. McKenney
198bbf8127 rcu: Remove "cpu" argument to rcu_prepare_for_idle()
The "cpu" argument to rcu_prepare_for_idle() is always the current
CPU, so drop it.  This in turn allows two of the uses of "cpu" in
this function to be replaced with a this_cpu_ptr() and the third by
smp_processor_id(), replacing that of the call to rcu_prepare_for_idle().
Again, the anticipated cross-CPU uses of these functions has been replaced
by NO_HZ_FULL.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:20:49 -08:00
Paul E. McKenney
aa6da5140b rcu: Remove "cpu" argument to rcu_needs_cpu()
The "cpu" argument to rcu_needs_cpu() is always the current CPU, so drop
it.  This in turn allows the "cpu" argument to rcu_cpu_has_callbacks()
to be removed, which allows the uses of "cpu" in both functions to be
replaced with a this_cpu_ptr().  Again, the anticipated cross-CPU uses
of these functions has been replaced by NO_HZ_FULL.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:20:43 -08:00
Paul E. McKenney
38200cf247 rcu: Remove "cpu" argument to rcu_note_context_switch()
The "cpu" argument to rcu_note_context_switch() is always the current
CPU, so drop it.  This in turn allows the "cpu" argument to
rcu_preempt_note_context_switch() to be removed, which allows the sole
use of "cpu" in both functions to be replaced with a this_cpu_ptr().
Again, the anticipated cross-CPU uses of these functions has been
replaced by NO_HZ_FULL.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:20:34 -08:00
Paul E. McKenney
86aea0e6e7 rcu: Remove "cpu" argument to rcu_preempt_check_callbacks()
Because rcu_preempt_check_callbacks()'s argument is guaranteed to
always be the current CPU, drop the argument and replace per_cpu()
with __this_cpu_read().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:20:26 -08:00
Paul E. McKenney
e3950ecd55 rcu: Remove "cpu" argument to rcu_pending()
Because rcu_pending()'s argument is guaranteed to always be the current
CPU, drop the argument and replace per_cpu_ptr() with this_cpu_ptr().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:20:18 -08:00
Paul E. McKenney
c3377c2da6 rcu: Remove "cpu" argument to rcu_check_callbacks()
The "cpu" argument was kept around on the off-chance that RCU might
offload scheduler-clock interrupts.  However, this offload approach
has been replaced by NO_HZ_FULL, which offloads -all- RCU processing
from qualifying CPUs.  It is therefore time to remove the "cpu" argument
to rcu_check_callbacks(), which this commit does.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:20:11 -08:00
Paul E. McKenney
11bbb235c2 rcu: Use DEFINE_PER_CPU_SHARED_ALIGNED for rcu_data
The rcu_data per-CPU variable has a number of fields that are atomically
manipulated, potentially by any CPU.  This situation can result in false
sharing with per-CPU variables that have the misfortune of being allocated
adjacent to rcu_data in memory.  This commit therefore changes the
DEFINE_PER_CPU() to DEFINE_PER_CPU_SHARED_ALIGNED() in order to avoid
this false sharing.

Reported-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:20:03 -08:00
Christoph Lameter
28ced795cb rcu: Remove rcu_dynticks * parameters when they are always this_cpu_ptr(&rcu_dynticks)
For some functions in kernel/rcu/tree* the rdtp parameter is always
this_cpu_ptr(rdtp).  Remove the parameter if constant and calculate the
pointer in function.

This will have the advantage that it is obvious that the address are
all per cpu offsets and thus it will enable the use of this_cpu_ops in
the future.

Signed-off-by: Christoph Lameter <cl@linux.com>
[ paulmck: Forward-ported to rcu/dev, whitespace adjustment. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-11-03 19:19:26 -08:00
Linus Torvalds
ab01f963de ACPI and power management fixes for 3.18-rc3
- Fix a crash on r8a7791/koelsch during resume from system suspend
    caused by a recent cpufreq-dt commit (Geert Uytterhoeven).
 
  - Fix an MFD enumeration problem introduced by a recent commit
    adding ACPI support to the MFD subsystem that exposed a weakness
    in the ACPI core causing ACPI enumeration to be applied to all
    devices associated with one ACPI companion object, although it
    should be used for one of them only (Mika Westerberg).
 
  - Fix an ACPI EC regression introduced during the 3.17 cycle
    causing some Samsung laptops to misbehave as a result of a
    workaround targeted at some Acer machines.  That includes
    a revert of a commit that went too far and a quirk for the
    Acer machines in question.  From Lv Zheng.
 
  - Fix a regression in the system suspend error code path introduced
    during the 3.15 cycle that causes it to fail to take errors from
    asychronous execution of "late" suspend callbacks into account
    (Imre Deak).
 
  - Fix a long-standing bug in the hibernation resume error code path
    that fails to roll back everything correcty on "freeze" callback
    errors and leaves some devices in a "suspended" state causing more
    breakage to happen subsequently (Imre Deak).
 
  - Make the cpufreq-dt driver disable operation performance points
    that are not supported by the VR connected to the CPU voltage
    plane with acceptable tolerance instead of constantly failing
    voltage scaling later on (Lucas Stach).
 
 /
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Merge tag 'pm+acpi-3.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael Wysocki:
 "These are fixes received after my previous pull request plus one that
  has been in the works for quite a while, but its previous version
  caused problems to happen, so it's been deferred till now.

  Fixed are two recent regressions (MFD enumeration and cpufreq-dt),
  ACPI EC regression introduced in 3.17, system suspend error code path
  regression introduced in 3.15, an older bug related to recovery from
  failing resume from hibernation and a cpufreq-dt driver issue related
  to operation performance points.

  Specifics:

   - Fix a crash on r8a7791/koelsch during resume from system suspend
     caused by a recent cpufreq-dt commit (Geert Uytterhoeven).

   - Fix an MFD enumeration problem introduced by a recent commit adding
     ACPI support to the MFD subsystem that exposed a weakness in the
     ACPI core causing ACPI enumeration to be applied to all devices
     associated with one ACPI companion object, although it should be
     used for one of them only (Mika Westerberg).

   - Fix an ACPI EC regression introduced during the 3.17 cycle causing
     some Samsung laptops to misbehave as a result of a workaround
     targeted at some Acer machines.  That includes a revert of a commit
     that went too far and a quirk for the Acer machines in question.
     From Lv Zheng.

   - Fix a regression in the system suspend error code path introduced
     during the 3.15 cycle that causes it to fail to take errors from
     asychronous execution of "late" suspend callbacks into account
     (Imre Deak).

   - Fix a long-standing bug in the hibernation resume error code path
     that fails to roll back everything correcty on "freeze" callback
     errors and leaves some devices in a "suspended" state causing more
     breakage to happen subsequently (Imre Deak).

   - Make the cpufreq-dt driver disable operation performance points
     that are not supported by the VR connected to the CPU voltage plane
     with acceptable tolerance instead of constantly failing voltage
     scaling later on (Lucas Stach)"

* tag 'pm+acpi-3.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / EC: Fix regression due to conflicting firmware behavior between Samsung and Acer.
  Revert "ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC"
  cpufreq: cpufreq-dt: Restore default cpumask_setall(policy->cpus)
  PM / Sleep: fix recovery during resuming from hibernation
  PM / Sleep: fix async suspend_late/freeze_late error handling
  ACPI: Use ACPI companion to match only the first physical device
  cpufreq: cpufreq-dt: disable unsupported OPPs
2014-10-31 19:08:25 -07:00
Linus Torvalds
89453379aa Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "A bit has accumulated, but it's been a week or so since my last batch
  of post-merge-window fixes, so...

   1) Missing module license in netfilter reject module, from Pablo.
      Lots of people ran into this.

   2) Off by one in mac80211 baserate calculation, from Karl Beldan.

   3) Fix incorrect return value from ax88179_178a driver's set_mac_addr
      op, which broke use of it with bonding.  From Ian Morgan.

   4) Checking of skb_gso_segment()'s return value was not all
      encompassing, it can return an SKB pointer, a pointer error, or
      NULL.  Fix from Florian Westphal.

      This is crummy, and longer term will be fixed to just return error
      pointers or a real SKB.

   6) Encapsulation offloads not being handled by
      skb_gso_transport_seglen().  From Florian Westphal.

   7) Fix deadlock in TIPC stack, from Ying Xue.

   8) Fix performance regression from using rhashtable for netlink
      sockets.  The problem was the synchronize_net() invoked for every
      socket destroy.  From Thomas Graf.

   9) Fix bug in eBPF verifier, and remove the strong dependency of BPF
      on NET.  From Alexei Starovoitov.

  10) In qdisc_create(), use the correct interface to allocate
      ->cpu_bstats, otherwise the u64_stats_sync member isn't
      initialized properly.  From Sabrina Dubroca.

  11) Off by one in ip_set_nfnl_get_byindex(), from Dan Carpenter.

  12) nf_tables_newchain() was erroneously expecting error pointers from
      netdev_alloc_pcpu_stats().  It only returna a valid pointer or
      NULL.  From Sabrina Dubroca.

  13) Fix use-after-free in _decode_session6(), from Li RongQing.

  14) When we set the TX flow hash on a socket, we mistakenly do so
      before we've nailed down the final source port.  Move the setting
      deeper to fix this.  From Sathya Perla.

  15) NAPI budget accounting in amd-xgbe driver was counting descriptors
      instead of full packets, fix from Thomas Lendacky.

  16) Fix total_data_buflen calculation in hyperv driver, from Haiyang
      Zhang.

  17) Fix bcma driver build with OF_ADDRESS disabled, from Hauke
      Mehrtens.

  18) Fix mis-use of per-cpu memory in TCP md5 code.  The problem is
      that something that ends up being vmalloc memory can't be passed
      to the crypto hash routines via scatter-gather lists.  From Eric
      Dumazet.

  19) Fix regression in promiscuous mode enabling in cdc-ether, from
      Olivier Blin.

  20) Bucket eviction and frag entry killing can race with eachother,
      causing an unlink of the object from the wrong list.  Fix from
      Nikolay Aleksandrov.

  21) Missing initialization of spinlock in cxgb4 driver, from Anish
      Bhatt.

  22) Do not cache ipv4 routing failures, otherwise if the sysctl for
      forwarding is subsequently enabled this won't be seen.  From
      Nicolas Cavallari"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (131 commits)
  drivers: net: cpsw: Support ALLMULTI and fix IFF_PROMISC in switch mode
  drivers: net: cpsw: Fix broken loop condition in switch mode
  net: ethtool: Return -EOPNOTSUPP if user space tries to read EEPROM with lengh 0
  stmmac: pci: set default of the filter bins
  net: smc91x: Fix gpios for device tree based booting
  mpls: Allow mpls_gso to be built as module
  mpls: Fix mpls_gso handler.
  r8152: stop submitting intr for -EPROTO
  netfilter: nft_reject_bridge: restrict reject to prerouting and input
  netfilter: nft_reject_bridge: don't use IP stack to reject traffic
  netfilter: nf_reject_ipv6: split nf_send_reset6() in smaller functions
  netfilter: nf_reject_ipv4: split nf_send_reset() in smaller functions
  netfilter: nf_tables_bridge: update hook_mask to allow {pre,post}routing
  drivers/net: macvtap and tun depend on INET
  drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packets
  drivers/net: Disable UFO through virtio
  net: skb_fclone_busy() needs to detect orphaned skb
  gre: Use inner mac length when computing tunnel length
  mlx4: Avoid leaking steering rules on flow creation error flow
  net/mlx4_en: Don't attempt to TX offload the outer UDP checksum for VXLAN
  ...
2014-10-31 15:04:58 -07:00
Linus Torvalds
f5fa363026 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Various scheduler fixes all over the place: three SCHED_DL fixes,
  three sched/numa fixes, two generic race fixes and a comment fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/dl: Fix preemption checks
  sched: Update comments for CLONE_NEWNS
  sched: stop the unbound recursion in preempt_schedule_context()
  sched/fair: Fix division by zero sysctl_numa_balancing_scan_size
  sched/fair: Care divide error in update_task_scan_period()
  sched/numa: Fix unsafe get_task_struct() in task_numa_assign()
  sched/deadline: Fix races between rt_mutex_setprio() and dl_task_timer()
  sched/deadline: Don't replenish from a !SCHED_DEADLINE entity
  sched: Fix race between task_group and sched_task_group
2014-10-31 14:05:35 -07:00
Linus Torvalds
5656b408ff Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, plus on the kernel side:

   - a revert for a newly introduced PMU driver which isn't complete yet
     and where we ran out of time with fixes (to be tried again in
     v3.19) - this makes up for a large chunk of the diffstat.

   - compilation warning fixes

   - a printk message fix

   - event_idx usage fixes/cleanups"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf probe: Trivial typo fix for --demangle
  perf tools: Fix report -F dso_from for data without branch info
  perf tools: Fix report -F dso_to for data without branch info
  perf tools: Fix report -F symbol_from for data without branch info
  perf tools: Fix report -F symbol_to for data without branch info
  perf tools: Fix report -F mispredict for data without branch info
  perf tools: Fix report -F in_tx for data without branch info
  perf tools: Fix report -F abort for data without branch info
  perf tools: Make CPUINFO_PROC an array to support different kernel versions
  perf callchain: Use global caching provided by libunwind
  perf/x86/intel: Revert incomplete and undocumented Broadwell client support
  perf/x86: Fix compile warnings for intel_uncore
  perf: Fix typos in sample code in the perf_event.h header
  perf: Fix and clean up initialization of pmu::event_idx
  perf: Fix bogus kernel printk
  perf diff: Add missing hists__init() call at tool start
2014-10-31 14:01:47 -07:00
Linus Torvalds
c958f9200f Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull futex fixes from Ingo Molnar:
 "This contains two futex fixes: one fixes a race condition, the other
  clarifies shared/private futex comments"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: Fix a race condition between REQUEUE_PI and task death
  futex: Mention key referencing differences between shared and private futexes
2014-10-31 13:57:45 -07:00
Linus Torvalds
aea4869f68 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core fixes from Ingo Molnar:
 "The tree contains two RCU fixes and a compiler quirk comment fix"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rcu: Make rcu_barrier() understand about missing rcuo kthreads
  compiler/gcc4+: Remove inaccurate comment about 'asm goto' miscompiles
  rcu: More on deadlock between CPU hotplug and expedited grace periods
2014-10-31 12:43:52 -07:00
Linus Torvalds
0f4b06766b Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "As you requested in the rc2 release mail the timer department serves
  you a few real bug fixes:

   - Fix the probe logic of the architected arm/arm64 timer
   - Plug a stack info leak in posix-timers
   - Prevent a shift out of bounds issue in the clockevents core"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ARM/ARM64: arch-timer: fix arch_timer_probed logic
  clockevents: Prevent shift out of bounds
  posix-timers: Fix stack info leak in timer_create()
2014-10-31 12:33:05 -07:00
Linus Torvalds
bcdfdaee5a ARM has system calls outside the NR_syscalls range, and the generic
tracing system does not support that and without checks, it can cause
 an oops to be reported.
 
 Rabin Vincent added checks in the return code on syscall events to make
 sure that the system call number is within the range that tracing
 knows about, and if not, simply ignores the system call.
 
 The system call tracing infrastructure needs to be rewritten to handle these
 cases better, but for now, to keep from oopsing, this patch will do.
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Merge tag 'trace-fixes-v3.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "ARM has system calls outside the NR_syscalls range, and the generic
  tracing system does not support that and without checks, it can cause
  an oops to be reported.

  Rabin Vincent added checks in the return code on syscall events to
  make sure that the system call number is within the range that tracing
  knows about, and if not, simply ignores the system call.

  The system call tracing infrastructure needs to be rewritten to handle
  these cases better, but for now, to keep from oopsing, this patch will
  do"

* tag 'trace-fixes-v3.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/syscalls: Ignore numbers outside NR_syscalls' range
2014-10-31 12:28:38 -07:00
Rabin Vincent
086ba77a6d tracing/syscalls: Ignore numbers outside NR_syscalls' range
ARM has some private syscalls (for example, set_tls(2)) which lie
outside the range of NR_syscalls.  If any of these are called while
syscall tracing is being performed, out-of-bounds array access will
occur in the ftrace and perf sys_{enter,exit} handlers.

 # trace-cmd record -e raw_syscalls:* true && trace-cmd report
 ...
 true-653   [000]   384.675777: sys_enter:            NR 192 (0, 1000, 3, 4000022, ffffffff, 0)
 true-653   [000]   384.675812: sys_exit:             NR 192 = 1995915264
 true-653   [000]   384.675971: sys_enter:            NR 983045 (76f74480, 76f74000, 76f74b28, 76f74480, 76f76f74, 1)
 true-653   [000]   384.675988: sys_exit:             NR 983045 = 0
 ...

 # trace-cmd record -e syscalls:* true
 [   17.289329] Unable to handle kernel paging request at virtual address aaaaaace
 [   17.289590] pgd = 9e71c000
 [   17.289696] [aaaaaace] *pgd=00000000
 [   17.289985] Internal error: Oops: 5 [#1] PREEMPT SMP ARM
 [   17.290169] Modules linked in:
 [   17.290391] CPU: 0 PID: 704 Comm: true Not tainted 3.18.0-rc2+ #21
 [   17.290585] task: 9f4dab00 ti: 9e710000 task.ti: 9e710000
 [   17.290747] PC is at ftrace_syscall_enter+0x48/0x1f8
 [   17.290866] LR is at syscall_trace_enter+0x124/0x184

Fix this by ignoring out-of-NR_syscalls-bounds syscall numbers.

Commit cd0980fc8a "tracing: Check invalid syscall nr while tracing syscalls"
added the check for less than zero, but it should have also checked
for greater than NR_syscalls.

Link: http://lkml.kernel.org/p/1414620418-29472-1-git-send-email-rabin@rab.in

Fixes: cd0980fc8a "tracing: Check invalid syscall nr while tracing syscalls"
Cc: stable@vger.kernel.org # 2.6.33+
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-10-30 20:58:38 -04:00
Richard Guy Briggs
897f1acbb6 audit: AUDIT_FEATURE_CHANGE message format missing delimiting space
Add a space between subj= and feature= fields to make them parsable.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paul Moore <pmoore@redhat.com>
2014-10-30 19:42:02 -04:00
Ingo Molnar
21ee24bf5b Merge branch 'urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent
Pull two RCU fixes from Paul E. McKenney:

" - Complete the work of commit dd56af42bd (rcu: Eliminate deadlock
    between CPU hotplug and expedited grace periods), which was
    intended to allow synchronize_sched_expedited() to be safely
    used when holding locks acquired by CPU-hotplug notifiers.
    This commit makes the put_online_cpus() avoid the deadlock
    instead of just handling the get_online_cpus().

  - Complete the work of commit 35ce7f29a4 (rcu: Create rcuo
    kthreads only for onlined CPUs), which was intended to allow
    RCU to avoid allocating unneeded kthreads on systems where the
    firmware says that there are more CPUs than are really present.
    This commit makes rcu_barrier() aware of the mismatch, so that
    it doesn't hang waiting for non-existent CPUs. "

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-30 07:37:37 +01:00
Martin Schwidefsky
0baf2a4dbf kernel/kmod: fix use-after-free of the sub_info structure
Found this in the message log on a s390 system:

    BUG kmalloc-192 (Not tainted): Poison overwritten
    Disabling lock debugging due to kernel taint
    INFO: 0x00000000684761f4-0x00000000684761f7. First byte 0xff instead of 0x6b
    INFO: Allocated in call_usermodehelper_setup+0x70/0x128 age=71 cpu=2 pid=648
     __slab_alloc.isra.47.constprop.56+0x5f6/0x658
     kmem_cache_alloc_trace+0x106/0x408
     call_usermodehelper_setup+0x70/0x128
     call_usermodehelper+0x62/0x90
     cgroup_release_agent+0x178/0x1c0
     process_one_work+0x36e/0x680
     worker_thread+0x2f0/0x4f8
     kthread+0x10a/0x120
     kernel_thread_starter+0x6/0xc
     kernel_thread_starter+0x0/0xc
    INFO: Freed in call_usermodehelper_exec+0x110/0x1b8 age=71 cpu=2 pid=648
     __slab_free+0x94/0x560
     kfree+0x364/0x3e0
     call_usermodehelper_exec+0x110/0x1b8
     cgroup_release_agent+0x178/0x1c0
     process_one_work+0x36e/0x680
     worker_thread+0x2f0/0x4f8
     kthread+0x10a/0x120
     kernel_thread_starter+0x6/0xc
     kernel_thread_starter+0x0/0xc

There is a use-after-free bug on the subprocess_info structure allocated
by the user mode helper.  In case do_execve() returns with an error
____call_usermodehelper() stores the error code to sub_info->retval, but
sub_info can already have been freed.

Regarding UMH_NO_WAIT, the sub_info structure can be freed by
__call_usermodehelper() before the worker thread returns from
do_execve(), allowing memory corruption when do_execve() failed after
exec_mmap() is called.

Regarding UMH_WAIT_EXEC, the call to umh_complete() allows
call_usermodehelper_exec() to continue which then frees sub_info.

To fix this race the code needs to make sure that the call to
call_usermodehelper_freeinfo() is always done after the last store to
sub_info->retval.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-29 16:33:14 -07:00
Riku Voipio
f601de2044 gcov: add ARM64 to GCOV_PROFILE_ALL
Following up the arm testing of gcov, turns out gcov on ARM64 works fine
as well.  Only change needed is adding ARM64 to Kconfig depends.

Tested with qemu and mach-virt

Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Acked-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>
2014-10-29 16:33:14 -07:00
Paul E. McKenney
bbe5d7a93a rcu: Fix for rcuo online-time-creation reorganization bug
Commit 35ce7f29a4 (rcu: Create rcuo kthreads only for onlined CPUs)
contains checks for the case where CPUs are brought online out of
order, re-wiring the rcuo leader-follower relationships as needed.
Unfortunately, this rewiring was broken.  This apparently went undetected
due to the tendency of systems to bring CPUs online in order.  This commit
nevertheless fixes the rewiring.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-10-29 10:20:08 -07:00
Paul E. McKenney
776d680711 rcu: Kick rcuo kthreads after their CPU goes offline
If a no-CBs CPU were to post an RCU callback with interrupts disabled
after it entered the idle loop for the last time, there might be no
deferred wakeup for the corresponding rcuo kthreads.  This commit
therefore adds a set of calls to do_nocb_deferred_wakeup() after the
CPU has gone completely offline.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-10-29 10:20:07 -07:00
Pranith Kumar
28f6569ab7 rcu: Remove redundant TREE_PREEMPT_RCU config option
PREEMPT_RCU and TREE_PREEMPT_RCU serve the same function after
TINY_PREEMPT_RCU has been removed. This patch removes TREE_PREEMPT_RCU
and uses PREEMPT_RCU config option in its place.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-10-29 10:20:05 -07:00
Clark Williams
21871d7eff rcu: Unify boost and kthread priorities
Rename CONFIG_RCU_BOOST_PRIO to CONFIG_RCU_KTHREAD_PRIO and use this
value for both the per-CPU kthreads (rcuc/N) and the rcu boosting
threads (rcub/n).

Also, create the module_parameter rcutree.kthread_prio to be used on
the kernel command line at boot to set a new value (rcutree.kthread_prio=N).

Signed-off-by: Clark Williams <clark.williams@gmail.com>
[ paulmck: Ported to rcu/dev, applied Paul Bolle and Peter Zijlstra feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-10-29 10:19:41 -07:00
Oleg Nesterov
392809b258 signal: Document the RCU protection of ->sighand
__cleanup_sighand() frees sighand without RCU grace period. This is
correct but this looks "obviously buggy" and constantly confuses the
readers, add the comments to explain how this works.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-10-29 10:07:18 -07:00
Paul E. McKenney
eca1a08986 signal: Exit RCU read-side critical section on each pass through loop
The kill_pid_info() can potentially loop indefinitely if tasks are created
and deleted sufficiently quickly, and if this happens, this function
will remain in a single RCU read-side critical section indefinitely.
This commit therefore exits the RCU read-side critical section on each
pass through the loop.  Because a race must happen to retry the loop,
this should have no performance impact in the common case.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2014-10-29 10:07:04 -07:00
Paul E. McKenney
e0775cefb5 rcu: Avoid IPIing idle CPUs from synchronize_sched_expedited()
Currently, synchronize_sched_expedited() sends IPIs to all online CPUs,
even those that are idle or executing in nohz_full= userspace.  Because
idle CPUs and nohz_full= userspace CPUs are in extended quiescent states,
there is no need to IPI them in the first place.  This commit therefore
avoids IPIing CPUs that are already in extended quiescent states.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-10-28 13:49:30 -07:00
Paul E. McKenney
61cfd0970e rcu: Move RCU_BOOST variable declarations, eliminating #ifdef
There are some RCU_BOOST-specific per-CPU variable declarations that
are needlessly defined under #ifdef in kernel/rcu/tree.c.  This commit
therefore moves these declarations into a pre-existing #ifdef in
kernel/rcu/tree_plugin.h.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-10-28 13:49:28 -07:00
Paul E. McKenney
0eafa46823 rcu: Remove CONFIG_RCU_CPU_STALL_VERBOSE
The CONFIG_RCU_CPU_STALL_VERBOSE Kconfig parameter causes preemptible
RCU's CPU stall warnings to dump out any preempted tasks that are blocking
the current RCU grace period.  This information is useful, and the default
has been CONFIG_RCU_CPU_STALL_VERBOSE=y for some years.  It is therefore
time for this commit to remove this Kconfig parameter, so that future
kernel builds will always act as if CONFIG_RCU_CPU_STALL_VERBOSE=y.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-10-28 13:48:13 -07:00
Linus Torvalds
6234056e13 Adding the new code for 3.19, I discovered a couple of minor bugs with
the accounting of the ftrace_ops trampoline logic. One was that the
 old hash was not updated before calling the modify code for an ftrace_ops.
 The second bug was what let the first bug go unnoticed, as the update would
 check the current hash for all ftrace_ops (where it should only check the
 old hash for modified ones). This let things work when only one ftrace_ops
 was registered to a function, but could break if more than one was
 registered depending on the order of the look ups.
 
 The worse thing that can happen if this bug triggers is that the ftrace
 self checks would find an anomaly and shut itself down.
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Merge tag 'trace-fixes-v3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull ftrace trampoline accounting fixes from Steven Rostedt:
 "Adding the new code for 3.19, I discovered a couple of minor bugs with
  the accounting of the ftrace_ops trampoline logic.

  One was that the old hash was not updated before calling the modify
  code for an ftrace_ops.  The second bug was what let the first bug go
  unnoticed, as the update would check the current hash for all
  ftrace_ops (where it should only check the old hash for modified
  ones).  This let things work when only one ftrace_ops was registered
  to a function, but could break if more than one was registered
  depending on the order of the look ups.

  The worse thing that can happen if this bug triggers is that the
  ftrace self checks would find an anomaly and shut itself down"

* tag 'trace-fixes-v3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix checking of trampoline ftrace_ops in finding trampoline
  ftrace: Set ops->old_hash on modifying what an ops hooks to
2014-10-28 13:27:19 -07:00
Paul E. McKenney
d7e2993396 rcu: Make rcu_barrier() understand about missing rcuo kthreads
Commit 35ce7f29a4 (rcu: Create rcuo kthreads only for onlined CPUs)
avoids creating rcuo kthreads for CPUs that never come online.  This
fixes a bug in many instances of firmware: Instead of lying about their
age, these systems instead lie about the number of CPUs that they have.
Before commit 35ce7f29a4, this could result in huge numbers of useless
rcuo kthreads being created.

It appears that experience indicates that I should have told the
people suffering from this problem to fix their broken firmware, but
I instead produced what turned out to be a partial fix.   The missing
piece supplied by this commit makes sure that rcu_barrier() knows not to
post callbacks for no-CBs CPUs that have not yet come online, because
otherwise rcu_barrier() will hang on systems having firmware that lies
about the number of CPUs.

It is tempting to simply have rcu_barrier() refuse to post a callback on
any no-CBs CPU that does not have an rcuo kthread.  This unfortunately
does not work because rcu_barrier() is required to wait for all pending
callbacks.  It is therefore required to wait even for those callbacks
that cannot possibly be invoked.  Even if doing so hangs the system.

Given that posting a callback to a no-CBs CPU that does not yet have an
rcuo kthread can hang rcu_barrier(), It is tempting to report an error
in this case.  Unfortunately, this will result in false positives at
boot time, when it is perfectly legal to post callbacks to the boot CPU
before the scheduler has started, in other words, before it is legal
to invoke rcu_barrier().

So this commit instead has rcu_barrier() avoid posting callbacks to
CPUs having neither rcuo kthread nor pending callbacks, and has it
complain bitterly if it finds CPUs having no rcuo kthread but some
pending callbacks.  And when rcu_barrier() does find CPUs having no rcuo
kthread but pending callbacks, as noted earlier, it has no choice but
to hang indefinitely.

Reported-by: Yanko Kaneti <yaneti@declera.com>
Reported-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Reported-by: Meelis Roos <mroos@linux.ee>
Reported-by: Eric B Munson <emunson@akamai.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Eric B Munson <emunson@akamai.com>
Tested-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Tested-by: Yanko Kaneti <yaneti@declera.com>
Tested-by: Kevin Fenzi <kevin@scrye.com>
Tested-by: Meelis Roos <mroos@linux.ee>
2014-10-28 13:24:13 -07:00
Peter Zijlstra
c719f56092 perf: Fix and clean up initialization of pmu::event_idx
Andy reported that the current state of event_idx is rather confused.
So remove all but the x86_pmu implementation and change the default to
return 0 (the safe option).

Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: Cody P Schafer <dev@codyps.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Himangi Saraogi <himangi774@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: sukadev@linux.vnet.ibm.com <sukadev@linux.vnet.ibm.com>
Cc: Thomas Huth <thuth@linux.vnet.ibm.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux390@de.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:51:01 +01:00
Kirill Tkhai
f3a7e1a9c4 sched/dl: Fix preemption checks
1) switched_to_dl() check is wrong. We reschedule only
   if rq->curr is deadline task, and we do not reschedule
   if it's a lower priority task. But we must always
   preempt a task of other classes.

2) dl_task_timer():
   Policy does not change in case of priority inheritance.
   rt_mutex_setprio() changes prio, while policy remains old.

So we lose some balancing logic in dl_task_timer() and
switched_to_dl() when we check policy instead of priority. Boosted
task may be rq->curr.

(I didn't change switched_from_dl() because no check is necessary
there at all).

I've looked at this place(switched_to_dl) several times and even fixed
this function, but found just now...  I suppose some performance tests
may work better after this.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1413909356.19914.128.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:46:10 +01:00
Oleg Nesterov
009f60e276 sched: stop the unbound recursion in preempt_schedule_context()
preempt_schedule_context() does preempt_enable_notrace() at the end
and this can call the same function again; exception_exit() is heavy
and it is quite possible that need-resched is true again.

1. Change this code to dec preempt_count() and check need_resched()
   by hand.

2. As Linus suggested, we can use the PREEMPT_ACTIVE bit and avoid
   the enable/disable dance around __schedule(). But in this case
   we need to move into sched/core.c.

3. Cosmetic, but x86 forgets to declare this function. This doesn't
   really matter because it is only called by asm helpers, still it
   make sense to add the declaration into asm/preempt.h to match
   preempt_schedule().

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Chuck Ebbert <cebbert.lkml@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20141005202322.GB27962@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:46:05 +01:00
Kirill Tkhai
6419265899 sched/fair: Fix division by zero sysctl_numa_balancing_scan_size
File /proc/sys/kernel/numa_balancing_scan_size_mb allows writing of zero.

This bash command reproduces problem:

$ while :; do echo 0 > /proc/sys/kernel/numa_balancing_scan_size_mb; \
	   echo 256 > /proc/sys/kernel/numa_balancing_scan_size_mb; done

	divide error: 0000 [#1] SMP
	Modules linked in:
	CPU: 0 PID: 24112 Comm: bash Not tainted 3.17.0+ #8
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
	task: ffff88013c852600 ti: ffff880037a68000 task.ti: ffff880037a68000
	RIP: 0010:[<ffffffff81074191>]  [<ffffffff81074191>] task_scan_min+0x21/0x50
	RSP: 0000:ffff880037a6bce0  EFLAGS: 00010246
	RAX: 0000000000000a00 RBX: 00000000000003e8 RCX: 0000000000000000
	RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88013c852600
	RBP: ffff880037a6bcf0 R08: 0000000000000001 R09: 0000000000015c90
	R10: ffff880239bf6c00 R11: 0000000000000016 R12: 0000000000003fff
	R13: ffff88013c852600 R14: ffffea0008d1b000 R15: 0000000000000003
	FS:  00007f12bb048700(0000) GS:ffff88007da00000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
	CR2: 0000000001505678 CR3: 0000000234770000 CR4: 00000000000006f0
	Stack:
	 ffff88013c852600 0000000000003fff ffff880037a6bd18 ffffffff810741d1
	 ffff88013c852600 0000000000003fff 000000000002bfff ffff880037a6bda8
	 ffffffff81077ef7 ffffea0008a56d40 0000000000000001 0000000000000001
	Call Trace:
	 [<ffffffff810741d1>] task_scan_max+0x11/0x40
	 [<ffffffff81077ef7>] task_numa_fault+0x1f7/0xae0
	 [<ffffffff8115a896>] ? migrate_misplaced_page+0x276/0x300
	 [<ffffffff81134a4d>] handle_mm_fault+0x62d/0xba0
	 [<ffffffff8103e2f1>] __do_page_fault+0x191/0x510
	 [<ffffffff81030122>] ? native_smp_send_reschedule+0x42/0x60
	 [<ffffffff8106dc00>] ? check_preempt_curr+0x80/0xa0
	 [<ffffffff8107092c>] ? wake_up_new_task+0x11c/0x1a0
	 [<ffffffff8104887d>] ? do_fork+0x14d/0x340
	 [<ffffffff811799bb>] ? get_unused_fd_flags+0x2b/0x30
	 [<ffffffff811799df>] ? __fd_install+0x1f/0x60
	 [<ffffffff8103e67c>] do_page_fault+0xc/0x10
	 [<ffffffff8150d322>] page_fault+0x22/0x30
	RIP  [<ffffffff81074191>] task_scan_min+0x21/0x50
	RSP <ffff880037a6bce0>
	---[ end trace 9a826d16936c04de ]---

Also fix race in task_scan_min (it depends on compiler behaviour).

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dario Faggioli <raistlin@linux.it>
Cc: David Rientjes <rientjes@google.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Link: http://lkml.kernel.org/r/1413455977.24793.78.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:46:04 +01:00