Commit Graph

17875 Commits

Author SHA1 Message Date
David S. Miller c99f7abf0e Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	include/net/inetpeer.h
	net/ipv6/output_core.c

Changes in net were fixing bugs in code removed in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-03 23:32:12 -07:00
Daniel Borkmann 3480593131 net: filter: get rid of BPF_S_* enum
This patch finally allows us to get rid of the BPF_S_* enum.
Currently, the code performs unnecessary encode and decode
workarounds in seccomp and filter migration itself when a filter
is being attached in order to overcome BPF_S_* encoding which
is not used anymore by the new interpreter resp. JIT compilers.

Keeping it around would mean that also in future we would need
to extend and maintain this enum and related encoders/decoders.
We can get rid of all that and save us these operations during
filter attaching. Naturally, also JIT compilers need to be updated
by this.

Before JIT conversion is being done, each compiler checks if A
is being loaded at startup to obtain information if it needs to
emit instructions to clear A first. Since BPF extensions are a
subset of BPF_LD | BPF_{W,H,B} | BPF_ABS variants, case statements
for extensions can be removed at that point. To ease and minimalize
code changes in the classic JITs, we have introduced bpf_anc_helper().

Tested with test_bpf on x86_64 (JIT, int), s390x (JIT, int),
arm (JIT, int), i368 (int), ppc64 (JIT, int); for sparc we
unfortunately didn't have access, but changes are analogous to
the rest.

Joint work with Alexei Starovoitov.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mircea Gherzan <mgherzan@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Acked-by: Chema Gonzalez <chemag@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-01 22:16:58 -07:00
Linus Torvalds 32439700fe 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 fixlets, mostly related to the (root-only) SCHED_DEADLINE
  policy, but also a hotplug bug fix and a fix for a NR_CPUS related
  overallocation bug causing a suspend/resume regression"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix hotplug vs. set_cpus_allowed_ptr()
  sched/cpupri: Replace NR_CPUS arrays
  sched/deadline: Replace NR_CPUS arrays
  sched/deadline: Restrict user params max value to 2^63 ns
  sched/deadline: Change sched_getparam() behaviour vs SCHED_DEADLINE
  sched: Disallow sched_attr::sched_policy < 0
  sched: Make sched_setattr() correctly return -EFBIG
2014-06-01 18:26:59 -07:00
Linus Torvalds a4bf79eb6a Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core futex/rtmutex fixes from Thomas Gleixner:
 "Three fixlets for long standing issues in the futex/rtmutex code
  unearthed by Dave Jones syscall fuzzer:

   - Add missing early deadlock detection checks in the futex code
   - Prevent user space from attaching a futex to kernel threads
   - Make the deadlock detector of rtmutex work again

  Looks large, but is more comments than code change"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rtmutex: Fix deadlock detector for real
  futex: Prevent attaching to kernel threads
  futex: Add another early deadlock detection check
2014-05-31 09:47:55 -07:00
Thomas Gleixner 397335f004 rtmutex: Fix deadlock detector for real
The current deadlock detection logic does not work reliably due to the
following early exit path:

	/*
	 * Drop out, when the task has no waiters. Note,
	 * top_waiter can be NULL, when we are in the deboosting
	 * mode!
	 */
	if (top_waiter && (!task_has_pi_waiters(task) ||
			   top_waiter != task_top_pi_waiter(task)))
		goto out_unlock_pi;

So this not only exits when the task has no waiters, it also exits
unconditionally when the current waiter is not the top priority waiter
of the task.

So in a nested locking scenario, it might abort the lock chain walk
and therefor miss a potential deadlock.

Simple fix: Continue the chain walk, when deadlock detection is
enabled.

We also avoid the whole enqueue, if we detect the deadlock right away
(A-A). It's an optimization, but also prevents that another waiter who
comes in after the detection and before the task has undone the damage
observes the situation and detects the deadlock and returns
-EDEADLOCK, which is wrong as the other task is not in a deadlock
situation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20140522031949.725272460@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-28 17:28:13 +02:00
Linus Torvalds 9e3d633178 Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull two powerpc fixes from Ben Herrenschmidt:
 "Here's a pair of powerpc fixes for 3.15 which are also going to
  stable.

  One's a fix for building with newer binutils (the problem currently
  only affects the BookE kernels but the affected macro might come back
  into use on BookS platforms at any time).  Unfortunately, the binutils
  maintainer did a backward incompatible change to a construct that we
  use so we have to add Makefile check.

  The other one is a fix for CPUs getting stuck in kexec when running
  single threaded.  Since we routinely use kexec on power (including in
  our newer bootloaders), I deemed that important enough"

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc, kexec: Fix "Processor X is stuck" issue during kexec from ST mode
  powerpc: Fix 64 bit builds with binutils 2.24
2014-05-28 08:06:50 -07:00
Srivatsa S. Bhat 011e4b02f1 powerpc, kexec: Fix "Processor X is stuck" issue during kexec from ST mode
If we try to perform a kexec when the machine is in ST (Single-Threaded) mode
(ppc64_cpu --smt=off), the kexec operation doesn't succeed properly, and we
get the following messages during boot:

[    0.089866] POWER8 performance monitor hardware support registered
[    0.089985] power8-pmu: PMAO restore workaround active.
[    5.095419] Processor 1 is stuck.
[   10.097933] Processor 2 is stuck.
[   15.100480] Processor 3 is stuck.
[   20.102982] Processor 4 is stuck.
[   25.105489] Processor 5 is stuck.
[   30.108005] Processor 6 is stuck.
[   35.110518] Processor 7 is stuck.
[   40.113369] Processor 9 is stuck.
[   45.115879] Processor 10 is stuck.
[   50.118389] Processor 11 is stuck.
[   55.120904] Processor 12 is stuck.
[   60.123425] Processor 13 is stuck.
[   65.125970] Processor 14 is stuck.
[   70.128495] Processor 15 is stuck.
[   75.131316] Processor 17 is stuck.

Note that only the sibling threads are stuck, while the primary threads (0, 8,
16 etc) boot just fine. Looking closer at the previous step of kexec, we observe
that kexec tries to wakeup (bring online) the sibling threads of all the cores,
before performing kexec:

[ 9464.131231] Starting new kernel
[ 9464.148507] kexec: Waking offline cpu 1.
[ 9464.148552] kexec: Waking offline cpu 2.
[ 9464.148600] kexec: Waking offline cpu 3.
[ 9464.148636] kexec: Waking offline cpu 4.
[ 9464.148671] kexec: Waking offline cpu 5.
[ 9464.148708] kexec: Waking offline cpu 6.
[ 9464.148743] kexec: Waking offline cpu 7.
[ 9464.148779] kexec: Waking offline cpu 9.
[ 9464.148815] kexec: Waking offline cpu 10.
[ 9464.148851] kexec: Waking offline cpu 11.
[ 9464.148887] kexec: Waking offline cpu 12.
[ 9464.148922] kexec: Waking offline cpu 13.
[ 9464.148958] kexec: Waking offline cpu 14.
[ 9464.148994] kexec: Waking offline cpu 15.
[ 9464.149030] kexec: Waking offline cpu 17.

Instrumenting this piece of code revealed that the cpu_up() operation actually
fails with -EBUSY. Thus, only the primary threads of all the cores are online
during kexec, and hence this is a sure-shot receipe for disaster, as explained
in commit e8e5c2155b (powerpc/kexec: Fix orphaned offline CPUs across kexec),
as well as in the comment above wake_offline_cpus().

It turns out that cpu_up() was returning -EBUSY because the variable
'cpu_hotplug_disabled' was set to 1; and this disabling of CPU hotplug was done
by migrate_to_reboot_cpu() inside kernel_kexec().

Now, migrate_to_reboot_cpu() was originally written with the assumption that
any further code will not need to perform CPU hotplug, since we are anyway in
the reboot path. However, kexec is clearly not such a case, since we depend on
onlining CPUs, atleast on powerpc.

So re-enable cpu-hotplug after returning from migrate_to_reboot_cpu() in the
kexec path, to fix this regression in kexec on powerpc.

Also, wrap the cpu_up() in powerpc kexec code within a WARN_ON(), so that we
can catch such issues more easily in the future.

Fixes: c97102ba96 (kexec: migrate to reboot cpu)
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-05-28 13:24:26 +10:00
David S. Miller 54e5c4def0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/bonding/bond_alb.c
	drivers/net/ethernet/altera/altera_msgdma.c
	drivers/net/ethernet/altera/altera_sgdma.c
	net/ipv6/xfrm6_output.c

Several cases of overlapping changes.

The xfrm6_output.c has a bug fix which overlaps the renaming
of skb->local_df to skb->ignore_df.

In the Altera TSE driver cases, the register access cleanups
in net-next overlapped with bug fixes done in net.

Similarly a bug fix to send ALB packets in the bonding driver using
the right source address overlaps with cleanups in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-24 00:32:30 -04:00
Linus Torvalds f02f79dbcb Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "The biggest commit is an irqtime accounting loop latency fix, the rest
  are misc fixes all over the place: deadline scheduling, docs, numa,
  balancer and a bad to-idle latency fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/numa: Initialize newidle balance stats in sd_numa_init()
  sched: Fix updating rq->max_idle_balance_cost and rq->next_balance in idle_balance()
  sched: Skip double execution of pick_next_task_fair()
  sched: Use CPUPRI_NR_PRIORITIES instead of MAX_RT_PRIO in cpupri check
  sched/deadline: Fix memory leak
  sched/deadline: Fix sched_yield() behavior
  sched: Sanitize irq accounting madness
  sched/docbook: Fix 'make htmldocs' warnings caused by missing description
2014-05-23 10:04:04 -07:00
Linus Torvalds e6a32c3ad1 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "The biggest changes are fixes for races that kept triggering Trinity
  crashes, plus liblockdep build fixes and smaller misc fixes.

  The liblockdep bits in perf/urgent are a pull mistake - they should
  have been in locking/urgent - but by the time I noticed other commits
  were added and testing was done :-/ Sorry about that"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix a race between ring_buffer_detach() and ring_buffer_attach()
  perf: Prevent false warning in perf_swevent_add
  perf: Limit perf_event_attr::sample_period to 63 bits
  tools/liblockdep: Remove all build files when doing make clean
  tools/liblockdep: Build liblockdep from tools/Makefile
  perf/x86/intel: Fix Silvermont's event constraints
  perf: Fix perf_event_init_context()
  perf: Fix race in removing an event
2014-05-23 10:02:34 -07:00
Lai Jiangshan 6acbfb9697 sched: Fix hotplug vs. set_cpus_allowed_ptr()
Lai found that:

  WARNING: CPU: 1 PID: 13 at arch/x86/kernel/smp.c:124 native_smp_send_reschedule+0x2d/0x4b()
  ...
  migration_cpu_stop+0x1d/0x22

was caused by set_cpus_allowed_ptr() assuming that cpu_active_mask is
always a sub-set of cpu_online_mask.

This isn't true since 5fbd036b55 ("sched: Cleanup cpu_active madness").

So set active and online at the same time to avoid this particular
problem.

Fixes: 5fbd036b55 ("sched: Cleanup cpu_active madness")
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael wang <wangyun@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Link: http://lkml.kernel.org/r/53758B12.8060609@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-22 10:21:31 +02:00
Peter Zijlstra 4dac0b6383 sched/cpupri: Replace NR_CPUS arrays
Tejun reported that his resume was failing due to order-3 allocations
from sched_domain building.

Replace the NR_CPUS arrays in there with a dynamically allocated
array.

Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-7cysnkw1gik45r864t1nkudh@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-22 10:21:29 +02:00
Peter Zijlstra 944770ab54 sched/deadline: Replace NR_CPUS arrays
Tejun reported that his resume was failing due to order-3 allocations
from sched_domain building.

Replace the NR_CPUS arrays in there with a dynamically allocated
array.

Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-kat4gl1m5a6dwy6nzuqox45e@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-22 10:21:28 +02:00
Juri Lelli b0827819b0 sched/deadline: Restrict user params max value to 2^63 ns
Michael Kerrisk noticed that creating SCHED_DEADLINE reservations
with certain parameters (e.g, a runtime of something near 2^64 ns)
can cause a system freeze for some amount of time.

The problem is that in the interface we have

 u64 sched_runtime;

while internally we need to have a signed runtime (to cope with
budget overruns)

 s64 runtime;

At the time we setup a new dl_entity we copy the first value in
the second. The cast turns out with negative values when
sched_runtime is too big, and this causes the scheduler to go crazy
right from the start.

Moreover, considering how we deal with deadlines wraparound

 (s64)(a - b) < 0

we also have to restrict acceptable values for sched_{deadline,period}.

This patch fixes the thing checking that user parameters are always
below 2^63 ns (still large enough for everyone).

It also rewrites other conditions that we check, since in
__checkparam_dl we don't have to deal with deadline wraparounds
and what we have now erroneously fails when the difference between
values is too big.

Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Dario Faggioli<raistlin@linux.it>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140513141131.20d944f81633ee937f256385@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-22 10:21:27 +02:00
Peter Zijlstra ce5f7f8200 sched/deadline: Change sched_getparam() behaviour vs SCHED_DEADLINE
The way we read POSIX one should only call sched_getparam() when
sched_getscheduler() returns either SCHED_FIFO or SCHED_RR.

Given that we currently return sched_param::sched_priority=0 for all
others, extend the same behaviour to SCHED_DEADLINE.

Requested-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Dario Faggioli <raistlin@linux.it>
Cc: linux-man <linux-man@vger.kernel.org>
Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140512205034.GH13467@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-22 10:21:26 +02:00
Peter Zijlstra dbdb22754f sched: Disallow sched_attr::sched_policy < 0
The scheduler uses policy=-1 to preserve the current policy state to
implement sys_sched_setparam(), this got exposed to userspace by
accident through sys_sched_setattr(), cure this.

Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140509085311.GJ30445@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-22 10:21:26 +02:00
Michael Kerrisk 143cf23df2 sched: Make sched_setattr() correctly return -EFBIG
The documented[1] behavior of sched_attr() in the proposed man page text is:

    sched_attr::size must be set to the size of the structure, as in
    sizeof(struct sched_attr), if the provided structure is smaller
    than the kernel structure, any additional fields are assumed
    '0'. If the provided structure is larger than the kernel structure,
    the kernel verifies all additional fields are '0' if not the
    syscall will fail with -E2BIG.

As currently implemented, sched_copy_attr() returns -EFBIG for
for this case, but the logic in sys_sched_setattr() converts that
error to -EFAULT. This patch fixes the behavior.

[1] http://thread.gmane.org/gmane.linux.kernel/1615615/focus=1697760

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/536CEC17.9070903@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-22 10:21:25 +02:00
Alexei Starovoitov 5fe821a9de net: filter: cleanup invocation of internal BPF
Kernel API for classic BPF socket filters is:

sk_unattached_filter_create() - validate classic BPF, convert, JIT
SK_RUN_FILTER() - run it
sk_unattached_filter_destroy() - destroy socket filter

Cleanup internal BPF kernel API as following:

sk_filter_select_runtime() - final step of internal BPF creation.
  Try to JIT internal BPF program, if JIT is not available select interpreter
SK_RUN_FILTER() - run it
sk_filter_free() - free internal BPF program

Disallow direct calls to BPF interpreter. Execution of the BPF program should
be done with SK_RUN_FILTER() macro.

Example of internal BPF create, run, destroy:

  struct sk_filter *fp;

  fp = kzalloc(sk_filter_size(prog_len), GFP_KERNEL);
  memcpy(fp->insni, prog, prog_len * sizeof(fp->insni[0]));
  fp->len = prog_len;

  sk_filter_select_runtime(fp);

  SK_RUN_FILTER(fp, ctx);

  sk_filter_free(fp);

Sockets, seccomp, testsuite, tracing are using different ways to populate
sk_filter, so first steps of program creation are not common.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-21 17:07:17 -04:00
Linus Torvalds 06eb4cc2e7 Merge branch 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull more cgroup fixes from Tejun Heo:
 "Three more patches to fix cgroup_freezer breakage due to the recent
  cgroup internal locking changes - an operation cgroup_freezer was
  using now requires sleepable context and cgroup_freezer was invoking
  that while holding a spin lock.  cgroup_freezer was using an overly
  elaborate hierarchical locking scheme.

  While it's possible to convert the hierarchical spinlocks directly to
  mutexes, this patch simplifies the overall locking so that it uses a
  global mutex.  This has the added benefit of avoiding iterating
  potentially huge number of tasks under a spinlock.  While the patch is
  on the larger side in the devel cycle, the changes made are mostly
  straight-forward and the locking logic is a lot simpler afterwards"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix rcu_read_lock() leak in update_if_frozen()
  cgroup_freezer: replace freezer->lock with freezer_mutex
  cgroup: introduce task_css_is_root()
2014-05-21 18:36:40 +09:00
Linus Torvalds 95d08585e0 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Gleixner:
 "A single bug fix for a long standing issue:

   - Updating the expiry value of a relative timer _after_ letting the
     idle logic select a target cpu for the timer based on its stale
     expiry value is outright stupid.  Thanks to Viresh for spotting the
     brainfart"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Set expiry time before switch_hrtimer_base()
2014-05-20 14:19:10 +09:00
Peter Zijlstra b69cf53640 perf: Fix a race between ring_buffer_detach() and ring_buffer_attach()
Alexander noticed that we use RCU iteration on rb->event_list but do
not use list_{add,del}_rcu() to add,remove entries to that list, nor
do we observe proper grace periods when re-using the entries.

Merge ring_buffer_detach() into ring_buffer_attach() such that
attaching to the NULL buffer is detaching.

Furthermore, ensure that between any 'detach' and 'attach' of the same
event we observe the required grace period, but only when strictly
required. In effect this means that only ioctl(.request =
PERF_EVENT_IOC_SET_OUTPUT) will wait for a grace period, while the
normal initial attach and final detach will not be delayed.

This patch should, I think, do the right thing under all
circumstances, the 'normal' cases all should never see the extra grace
period, but the two cases:

 1) PERF_EVENT_IOC_SET_OUTPUT on an event which already has a
    ring_buffer set, will now observe the required grace period between
    removing itself from the old and attaching itself to the new buffer.

    This case is 'simple' in that both buffers are present in
    perf_event_set_output() one could think an unconditional
    synchronize_rcu() would be sufficient; however...

 2) an event that has a buffer attached, the buffer is destroyed
    (munmap) and then the event is attached to a new/different buffer
    using PERF_EVENT_IOC_SET_OUTPUT.

    This case is more complex because the buffer destruction does:
      ring_buffer_attach(.rb = NULL)
    followed by the ioctl() doing:
      ring_buffer_attach(.rb = foo);

    and we still need to observe the grace period between these two
    calls due to us reusing the event->rb_entry list_head.

In order to make 2 happen we use Paul's latest cond_synchronize_rcu()
call.

Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Reported-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140507123526.GD13658@twins.programming.kicks-ass.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-19 21:44:56 +09:00
Jiri Olsa 39af6b1678 perf: Prevent false warning in perf_swevent_add
The perf cpu offline callback takes down all cpu context
events and releases swhash->swevent_hlist.

This could race with task context software event being just
scheduled on this cpu via perf_swevent_add while cpu hotplug
code already cleaned up event's data.

The race happens in the gap between the cpu notifier code
and the cpu being actually taken down. Note that only cpu
ctx events are terminated in the perf cpu hotplug code.

It's easily reproduced with:
  $ perf record -e faults perf bench sched pipe

while putting one of the cpus offline:
  # echo 0 > /sys/devices/system/cpu/cpu1/online

Console emits following warning:
  WARNING: CPU: 1 PID: 2845 at kernel/events/core.c:5672 perf_swevent_add+0x18d/0x1a0()
  Modules linked in:
  CPU: 1 PID: 2845 Comm: sched-pipe Tainted: G        W    3.14.0+ #256
  Hardware name: Intel Corporation Montevina platform/To be filled by O.E.M., BIOS AMVACRB1.86C.0066.B00.0805070703 05/07/2008
   0000000000000009 ffff880077233ab8 ffffffff81665a23 0000000000200005
   0000000000000000 ffff880077233af8 ffffffff8104732c 0000000000000046
   ffff88007467c800 0000000000000002 ffff88007a9cf2a0 0000000000000001
  Call Trace:
   [<ffffffff81665a23>] dump_stack+0x4f/0x7c
   [<ffffffff8104732c>] warn_slowpath_common+0x8c/0xc0
   [<ffffffff8104737a>] warn_slowpath_null+0x1a/0x20
   [<ffffffff8110fb3d>] perf_swevent_add+0x18d/0x1a0
   [<ffffffff811162ae>] event_sched_in.isra.75+0x9e/0x1f0
   [<ffffffff8111646a>] group_sched_in+0x6a/0x1f0
   [<ffffffff81083dd5>] ? sched_clock_local+0x25/0xa0
   [<ffffffff811167e6>] ctx_sched_in+0x1f6/0x450
   [<ffffffff8111757b>] perf_event_sched_in+0x6b/0xa0
   [<ffffffff81117a4b>] perf_event_context_sched_in+0x7b/0xc0
   [<ffffffff81117ece>] __perf_event_task_sched_in+0x43e/0x460
   [<ffffffff81096f1e>] ? put_lock_stats.isra.18+0xe/0x30
   [<ffffffff8107b3c8>] finish_task_switch+0xb8/0x100
   [<ffffffff8166a7de>] __schedule+0x30e/0xad0
   [<ffffffff81172dd2>] ? pipe_read+0x3e2/0x560
   [<ffffffff8166b45e>] ? preempt_schedule_irq+0x3e/0x70
   [<ffffffff8166b45e>] ? preempt_schedule_irq+0x3e/0x70
   [<ffffffff8166b464>] preempt_schedule_irq+0x44/0x70
   [<ffffffff816707f0>] retint_kernel+0x20/0x30
   [<ffffffff8109e60a>] ? lockdep_sys_exit+0x1a/0x90
   [<ffffffff812a4234>] lockdep_sys_exit_thunk+0x35/0x67
   [<ffffffff81679321>] ? sysret_check+0x5/0x56

Fixing this by tracking the cpu hotplug state and displaying
the WARN only if current cpu is initialized properly.

Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: stable@vger.kernel.org
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1396861448-10097-1-git-send-email-jolsa@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-19 21:44:55 +09:00
Peter Zijlstra 0819b2e30c perf: Limit perf_event_attr::sample_period to 63 bits
Vince reported that using a large sample_period (one with bit 63 set)
results in wreckage since while the sample_period is fundamentally
unsigned (negative periods don't make sense) the way we implement
things very much rely on signed logic.

So limit sample_period to 63 bits to avoid tripping over this.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/n/tip-p25fhunibl4y3qi0zuqmyf4b@git.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-19 21:44:55 +09:00
Thomas Gleixner f0d71b3dcb futex: Prevent attaching to kernel threads
We happily allow userspace to declare a random kernel thread to be the
owner of a user space PI futex.

Found while analysing the fallout of Dave Jones syscall fuzzer.

We also should validate the thread group for private futexes and find
some fast way to validate whether the "alleged" owner has RW access on
the file which backs the SHM, but that's a separate issue.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <darren@dvhart.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Carlos ODonell <carlos@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20140512201701.194824402@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
2014-05-19 21:18:49 +09:00
Thomas Gleixner 866293ee54 futex: Add another early deadlock detection check
Dave Jones trinity syscall fuzzer exposed an issue in the deadlock
detection code of rtmutex:
  http://lkml.kernel.org/r/20140429151655.GA14277@redhat.com

That underlying issue has been fixed with a patch to the rtmutex code,
but the futex code must not call into rtmutex in that case because
    - it can detect that issue early
    - it avoids a different and more complex fixup for backing out

If the user space variable got manipulated to 0x80000000 which means
no lock holder, but the waiters bit set and an active pi_state in the
kernel is found we can figure out the recursive locking issue by
looking at the pi_state owner. If that is the current task, then we
can safely return -EDEADLK.

The check should have been added in commit 59fa62451 (futex: Handle
futex_pi OWNER_DIED take over correctly) already, but I did not see
the above issue caused by user space manipulation back then.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <darren@dvhart.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Carlos ODonell <carlos@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20140512201701.097349971@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
2014-05-19 21:18:49 +09:00
Alexei Starovoitov 8f577cadf7 seccomp: JIT compile seccomp filter
Take advantage of internal BPF JIT

05-sim-long_jumps.c of libseccomp was used as micro-benchmark:

 seccomp_rule_add_exact(ctx,...
 seccomp_rule_add_exact(ctx,...

 rc = seccomp_load(ctx);

 for (i = 0; i < 10000000; i++)
    syscall(...);

$ sudo sysctl net.core.bpf_jit_enable=1
$ time ./bench
real	0m2.769s
user	0m1.136s
sys	0m1.624s

$ sudo sysctl net.core.bpf_jit_enable=0
$ time ./bench
real	0m5.825s
user	0m1.268s
sys	0m4.548s

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-15 16:31:30 -04:00
WANG Cong 122ff243f5 ipv4: make ip_local_reserved_ports per netns
ip_local_port_range is already per netns, so should ip_local_reserved_ports
be. And since it is none by default we don't actually need it when we don't
enable CONFIG_SYSCTL.

By the way, rename inet_is_reserved_local_port() to inet_is_local_reserved_port()

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-14 15:31:45 -04:00
Tejun Heo 36e9d2ebcc cgroup: fix rcu_read_lock() leak in update_if_frozen()
While updating cgroup_freezer locking, 68fafb77d827 ("cgroup_freezer:
replace freezer->lock with freezer_mutex") introduced a bug in
update_if_frozen() where it returns with rcu_read_lock() held.  Fix it
by adding rcu_read_unlock() before returning.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
2014-05-13 11:28:30 -04:00
Tejun Heo e5ced8ebb1 cgroup_freezer: replace freezer->lock with freezer_mutex
After 96d365e0b8 ("cgroup: make css_set_lock a rwsem and rename it
to css_set_rwsem"), css task iterators requires sleepable context as
it may block on css_set_rwsem.  I missed that cgroup_freezer was
iterating tasks under IRQ-safe spinlock freezer->lock.  This leads to
errors like the following on freezer state reads and transitions.

  BUG: sleeping function called from invalid context at /work
 /os/work/kernel/locking/rwsem.c:20
  in_atomic(): 0, irqs_disabled(): 0, pid: 462, name: bash
  5 locks held by bash/462:
   #0:  (sb_writers#7){.+.+.+}, at: [<ffffffff811f0843>] vfs_write+0x1a3/0x1c0
   #1:  (&of->mutex){+.+.+.}, at: [<ffffffff8126d78b>] kernfs_fop_write+0xbb/0x170
   #2:  (s_active#70){.+.+.+}, at: [<ffffffff8126d793>] kernfs_fop_write+0xc3/0x170
   #3:  (freezer_mutex){+.+...}, at: [<ffffffff81135981>] freezer_write+0x61/0x1e0
   #4:  (rcu_read_lock){......}, at: [<ffffffff81135973>] freezer_write+0x53/0x1e0
  Preemption disabled at:[<ffffffff81104404>] console_unlock+0x1e4/0x460

  CPU: 3 PID: 462 Comm: bash Not tainted 3.15.0-rc1-work+ #10
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
   ffff88000916a6d0 ffff88000e0a3da0 ffffffff81cf8c96 0000000000000000
   ffff88000e0a3dc8 ffffffff810cf4f2 ffffffff82388040 ffff880013aaf740
   0000000000000002 ffff88000e0a3de8 ffffffff81d05974 0000000000000246
  Call Trace:
   [<ffffffff81cf8c96>] dump_stack+0x4e/0x7a
   [<ffffffff810cf4f2>] __might_sleep+0x162/0x260
   [<ffffffff81d05974>] down_read+0x24/0x60
   [<ffffffff81133e87>] css_task_iter_start+0x27/0x70
   [<ffffffff8113584d>] freezer_apply_state+0x5d/0x130
   [<ffffffff81135a16>] freezer_write+0xf6/0x1e0
   [<ffffffff8112eb88>] cgroup_file_write+0xd8/0x230
   [<ffffffff8126d7b7>] kernfs_fop_write+0xe7/0x170
   [<ffffffff811f0756>] vfs_write+0xb6/0x1c0
   [<ffffffff811f121d>] SyS_write+0x4d/0xc0
   [<ffffffff81d08292>] system_call_fastpath+0x16/0x1b

freezer->lock used to be used in hot paths but that time is long gone
and there's no reason for the lock to be IRQ-safe spinlock or even
per-cgroup.  In fact, given the fact that a cgroup may contain large
number of tasks, it's not a good idea to iterate over them while
holding IRQ-safe spinlock.

Let's simplify locking by replacing per-cgroup freezer->lock with
global freezer_mutex.  This also makes the comments explaining the
intricacies of policy inheritance and the locking around it as the
states are protected by a common mutex.

The conversion is mostly straight-forward.  The followings are worth
mentioning.

* freezer_css_online() no longer needs double locking.

* freezer_attach() now performs propagation simply while holding
  freezer_mutex.  update_if_frozen() race no longer exists and the
  comment is removed.

* freezer_fork() now tests whether the task is in root cgroup using
  the new task_css_is_root() without doing rcu_read_lock/unlock().  If
  not, it grabs freezer_mutex and performs the operation.

* freezer_read() and freezer_change_state() grab freezer_mutex across
  the whole operation and pin the css while iterating so that each
  descendant processing happens in sleepable context.

Fixes: 96d365e0b8 ("cgroup: make css_set_lock a rwsem and rename it to css_set_rwsem")
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-05-13 11:26:31 -04:00
Tejun Heo 5024ae29cd cgroup: introduce task_css_is_root()
Determining the css of a task usually requires RCU read lock as that's
the only thing which keeps the returned css accessible till its
reference is acquired; however, testing whether a task belongs to the
root can be performed without dereferencing the returned css by
comparing the returned pointer against the root one in init_css_set[]
which never changes.

Implement task_css_is_root() which can be invoked in any context.
This will be used by the scheduled cgroup_freezer change.

v2: cgroup no longer supports modular controllers.  No need to export
    init_css_set.  Pointed out by Li.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-05-13 11:26:27 -04:00
Linus Torvalds efb2b1d5fd Merge branch 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fixes from Tejun Heo:
 "Fixes for two bugs in workqueue.

  One is exiting with internal mutex held in a failure path of
  wq_update_unbound_numa().  The other is a subtle and unlikely
  use-after-possible-last-put in the rescuer logic.  Both have been
  around for quite some time now and are unlikely to have triggered
  noticeably often.  All patches are marked for -stable backport"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix a possible race condition between rescuer and pwq-release
  workqueue: make rescuer_thread() empty wq->maydays list before exiting
  workqueue: fix bugs in wq_update_unbound_numa() failure path
2014-05-13 11:24:07 +09:00
Linus Torvalds 26a41cd1ee Merge branch 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "During recent restructuring, device_cgroup unified config input check
  and enforcement logic; unfortunately, it turned out to share too much.
  Aristeu's patches fix the breakage and marked for -stable backport.

  The other two patches are fallouts from kernfs conversion.  The blkcg
  change is temporary and will go away once kernfs internal locking gets
  simplified (patches pending)"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  blkcg: use trylock on blkcg_pol_mutex in blkcg_reset_stats()
  device_cgroup: check if exception removal is allowed
  device_cgroup: fix the comment format for recently added functions
  device_cgroup: rework device access check and exception checking
  cgroup: fix the retry path of cgroup_mount()
2014-05-13 11:22:57 +09:00
David S. Miller 5f013c9bc7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/altera/altera_sgdma.c
	net/netlink/af_netlink.c
	net/sched/cls_api.c
	net/sched/sch_api.c

The netlink conflict dealt with moving to netlink_capable() and
netlink_ns_capable() in the 'net' tree vs. supporting 'tc' operations
in non-init namespaces.  These were simple transformations from
netlink_capable to netlink_ns_capable.

The Altera driver conflict was simply code removal overlapping some
void pointer cast cleanups in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-12 13:19:14 -04:00
Viresh Kumar 84ea7fe379 hrtimer: Set expiry time before switch_hrtimer_base()
switch_hrtimer_base() calls hrtimer_check_target() which ensures that
we do not migrate a timer to a remote cpu if the timer expires before
the current programmed expiry time on that remote cpu.

But __hrtimer_start_range_ns() calls switch_hrtimer_base() before the
new expiry time is set. So the sanity check in hrtimer_check_target()
is operating on stale or even uninitialized data.

Update expiry time before calling switch_hrtimer_base().

[ tglx: Rewrote changelog once again ]

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: linaro-networking@linaro.org
Cc: fweisbec@gmail.com
Cc: arvind.chauhan@arm.com
Link: http://lkml.kernel.org/r/81999e148745fc51bbcd0615823fbab9b2e87e23.1399882253.git.viresh.kumar@linaro.org
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-12 10:47:39 +02:00
Linus Torvalds 181da3c34a Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
 "A somewhat unpleasantly large collection of small fixes.  The big ones
  are the __visible tree sweep and a fix for 'earlyprintk=efi,keep'.  It
  was using __init functions with predictably suboptimal results.

  Another key fix is a build fix which would produce output that simply
  would not decompress correctly in some configuration, due to the
  existing Makefiles picking up an unfortunate local label and mistaking
  it for the global symbol _end.

  Additional fixes include the handling of 64-bit numbers when setting
  the vdso data page (a latent bug which became manifest when i386
  started exporting a vdso with time functions), a fix to the new MSR
  manipulation accessors which would cause features to not get properly
  unblocked, a build fix for 32-bit userland, and a few new platform
  quirks"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, vdso, time: Cast tv_nsec to u64 for proper shifting in update_vsyscall()
  x86: Fix typo in MSR_IA32_MISC_ENABLE_LIMIT_CPUID macro
  x86: Fix typo preventing msr_set/clear_bit from having an effect
  x86/intel: Add quirk to disable HPET for the Baytrail platform
  x86/hpet: Make boot_hpet_disable extern
  x86-64, build: Fix stack protector Makefile breakage with 32-bit userland
  x86/reboot: Add reboot quirk for Certec BPC600
  asmlinkage: Add explicit __visible to drivers/*, lib/*, kernel/*
  asmlinkage, x86: Add explicit __visible to arch/x86/*
  asmlinkage: Revert "lto: Make asmlinkage __visible"
  x86, build: Don't get confused by local symbols
  x86/efi: earlyprintk=efi,keep fix
2014-05-09 12:24:20 -07:00
Linus Torvalds f322e26238 This contains two fixes.
The first is a long standing bug that causes bogus data to show up
 in the refcnt field of the module_refcnt tracepoint. It was
 introduced by a merge conflict resolution back in 2.6.35-rc days.
 
 The result should be refcnt = incs - decs, but instead it did
 refcnt = incs + decs.
 
 The second fix is to a bug that was introduced in this merge window
 that allowed for a tracepoint funcs pointer to be used after it
 was freed. Moving the location of where the probes are released
 solved the problem.
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Merge tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "This contains two fixes.

  The first is a long standing bug that causes bogus data to show up in
  the refcnt field of the module_refcnt tracepoint.  It was introduced
  by a merge conflict resolution back in 2.6.35-rc days.

  The result should be 'refcnt = incs - decs', but instead it did
  'refcnt = incs + decs'.

  The second fix is to a bug that was introduced in this merge window
  that allowed for a tracepoint funcs pointer to be used after it was
  freed.  Moving the location of where the probes are released solved
  the problem"

* tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracepoint: Fix use of tracepoint funcs after rcu free
  trace: module: Maintain a valid user count
2014-05-08 14:17:13 -07:00
Mathieu Desnoyers 8058bd0faa tracepoint: Fix use of tracepoint funcs after rcu free
Commit de7b297390 "tracepoint: Use struct pointer instead of name hash
for reg/unreg tracepoints" introduces a use after free by calling
release_probes on the old struct tracepoint array before the newly
allocated array is published with rcu_assign_pointer. There is a race
window where tracepoints (RCU readers) can perform a
"use-after-grace-period-after-free", which shows up as a GPF in
stress-tests.

Link: http://lkml.kernel.org/r/53698021.5020108@oracle.com
Link: http://lkml.kernel.org/p/1399549669-25465-1-git-send-email-mathieu.desnoyers@efficios.com

Reported-by: Sasha Levin <sasha.levin@oracle.com>
CC: Oleg Nesterov <oleg@redhat.com>
CC: Dave Jones <davej@redhat.com>
Fixes: de7b297390 "tracepoint: Use struct pointer instead of name hash for reg/unreg tracepoints"
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-05-08 09:10:56 -04:00
Jason Low 2b4cfe64de sched/numa: Initialize newidle balance stats in sd_numa_init()
Also initialize the per-sd variables for newidle load balancing
in sd_numa_init().

Signed-off-by: Jason Low <jason.low2@hp.com>
Acked-by: morten.rasmussen@arm.com
Cc: daniel.lezcano@linaro.org
Cc: alex.shi@linaro.org
Cc: preeti@linux.vnet.ibm.com
Cc: efault@gmx.de
Cc: vincent.guittot@linaro.org
Cc: aswin@hp.com
Cc: chegu_vinod@hp.com
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1398303035-18255-3-git-send-email-jason.low2@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:51:37 +02:00
Jason Low 0e5b5337f0 sched: Fix updating rq->max_idle_balance_cost and rq->next_balance in idle_balance()
The following commit:

  e5fc66119e ("sched: Fix race in idle_balance()")

can potentially cause rq->max_idle_balance_cost to not be updated,
even when load_balance(NEWLY_IDLE) is attempted and the per-sd
max cost value is updated.

Preeti noticed a similar issue with updating rq->next_balance.

In this patch, we fix this by making sure we still check/update those values
even if a task gets enqueued while browsing the domains.

Signed-off-by: Jason Low <jason.low2@hp.com>
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: morten.rasmussen@arm.com
Cc: aswin@hp.com
Cc: daniel.lezcano@linaro.org
Cc: alex.shi@linaro.org
Cc: efault@gmx.de
Cc: vincent.guittot@linaro.org
Link: http://lkml.kernel.org/r/1398725155-7591-2-git-send-email-jason.low2@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:51:36 +02:00
Peter Zijlstra 6ccdc84b81 sched: Skip double execution of pick_next_task_fair()
Tim wrote:

 "The current code will call pick_next_task_fair a second time in the
  slow path if we did not pull any task in our first try.  This is
  really unnecessary as we already know no task can be pulled and it
  doubles the delay for the cpu to enter idle.

  We instrumented some network workloads and that saw that
  pick_next_task_fair is frequently called twice before a cpu enters
  idle.  The call to pick_next_task_fair can add non trivial latency as
  it calls load_balance which runs find_busiest_group on an hierarchy of
  sched domains spanning the cpus for a large system.  For some 4 socket
  systems, we saw almost 0.25 msec spent per call of pick_next_task_fair
  before a cpu can be idled."

Optimize the second call away for the common case and document the
dependency.

Reported-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Len Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/20140424100047.GP11096@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:51:35 +02:00
Steven Rostedt (Red Hat) 6227cb00cc sched: Use CPUPRI_NR_PRIORITIES instead of MAX_RT_PRIO in cpupri check
The check at the beginning of cpupri_find() makes sure that the task_pri
variable does not exceed the cp->pri_to_cpu array length. But that length
is CPUPRI_NR_PRIORITIES not MAX_RT_PRIO, where it will miss the last two
priorities in that array.

As task_pri is computed from convert_prio() which should never be bigger
than CPUPRI_NR_PRIORITIES, if the check should cause a panic if it is
hit.

Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1397015410.5212.13.camel@marge.simpson.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:51:33 +02:00
Li Zefan 6a7cd273dc sched/deadline: Fix memory leak
Free cpudl->free_cpus allocated in cpudl_init().

Signed-off-by: Li Zefan <lizefan@huawei.com>
Acked-by: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org> # 3.14+
Link: http://lkml.kernel.org/r/534F36CE.2000409@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:51:32 +02:00
Juri Lelli 5bfd126e80 sched/deadline: Fix sched_yield() behavior
yield_task_dl() is broken:

 o it forces current to be throttled setting its runtime to zero;
 o it sets current's dl_se->dl_new to one, expecting that dl_task_timer()
   will queue it back with proper parameters at replenish time.

Unfortunately, dl_task_timer() has this check at the very beginning:

	if (!dl_task(p) || dl_se->dl_new)
		goto unlock;

So, it just bails out and the task is never replenished. It actually
yielded forever.

To fix this, introduce a new flag indicating that the task properly yielded
the CPU before its current runtime expired. While this is a little overdoing
at the moment, the flag would be useful in the future to discriminate between
"good" jobs (of which remaining runtime could be reclaimed, i.e. recycled)
and "bad" jobs (for which dl_throttled task has been set) that needed to be
stopped.

Reported-by: yjay.kim <yjay.kim@lge.com>
Signed-off-by: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140429103953.e68eba1b2ac3309214e3dc5a@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:51:31 +02:00
Thomas Gleixner 2d513868e2 sched: Sanitize irq accounting madness
Russell reported, that irqtime_account_idle_ticks() takes ages due to:

       for (i = 0; i < ticks; i++)
               irqtime_account_process_tick(current, 0, rq);

It's sad, that this code was written way _AFTER_ the NOHZ idle
functionality was available. I charge myself guitly for not paying
attention when that crap got merged with commit abb74cefa ("sched:
Export ns irqtimes through /proc/stat")

So instead of looping nr_ticks times just apply the whole thing at
once.

As a side note: The whole cputime_t vs. u64 business in that context
wants to be cleaned up as well. There is no point in having all these
back and forth conversions. Lets standardise on u64 nsec for all
kernel internal accounting and be done with it. Everything else does
not make sense at all for fine grained accounting. Frederic, can you
please take care of that?

Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: Shaun Ruffell <sruffell@digium.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1405022307000.6261@ionos.tec.linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:51:30 +02:00
Peter Zijlstra ffb4ef21ac perf: Fix perf_event_init_context()
perf_pin_task_context() can return NULL but perf_event_init_context()
assumes it will not, correct this.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Link: http://lkml.kernel.org/r/20140505171428.GU26782@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:33:15 +02:00
Peter Zijlstra 46ce0fe97a perf: Fix race in removing an event
When removing a (sibling) event we do:

	raw_spin_lock_irq(&ctx->lock);
	perf_group_detach(event);
	raw_spin_unlock_irq(&ctx->lock);

	<hole>

	perf_remove_from_context(event);
		raw_spin_lock_irq(&ctx->lock);
		...
		raw_spin_unlock_irq(&ctx->lock);

Now, assuming the event is a sibling, it will be 'unreachable' for
things like ctx_sched_out() because that iterates the
groups->siblings, and we just unhooked the sibling.

So, if during <hole> we get ctx_sched_out(), it will miss the event
and not call event_sched_out() on it, leaving it programmed on the
PMU.

The subsequent perf_remove_from_context() call will find the ctx is
inactive and only call list_del_event() to remove the event from all
other lists.

Hereafter we can proceed to free the event; while still programmed!

Close this hole by moving perf_group_detach() inside the same
ctx->lock region(s) perf_remove_from_context() has.

The condition on inherited events only in __perf_event_exit_task() is
likely complete crap because non-inherited events are part of groups
too and we're tearing down just the same. But leave that for another
patch.

Most-likely-Fixes: e03a9a55b4 ("perf: Change close() semantics for group events")
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Much-staring-at-traces-by: Vince Weaver <vincent.weaver@maine.edu>
Much-staring-at-traces-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140505093124.GN17778@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:33:14 +02:00
Andi Kleen 722a9f9299 asmlinkage: Add explicit __visible to drivers/*, lib/*, kernel/*
As requested by Linus add explicit __visible to the asmlinkage users.
This marks functions visible to assembler.

Tree sweep for rest of tree.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1398984278-29319-4-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-05 16:07:46 -07:00
Linus Torvalds 2080cee435 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) e1000e computes header length incorrectly wrt vlans, fix from Vlad
    Yasevich.

 2) ns_capable() check in sock_diag netlink code, from Andrew
    Lutomirski.

 3) Fix invalid queue pairs handling in virtio_net, from Amos Kong.

 4) Checksum offloading busted in sxgbe driver due to incorrect
    descriptor layout, fix from Byungho An.

 5) Fix build failure with SMC_DEBUG set to 2 or larger, from Zi Shen
    Lim.

 6) Fix uninitialized A and X registers in BPF interpreter, from Alexei
    Starovoitov.

 7) Fix arch dependencies of candence driver.

 8) Fix netlink capabilities checking tree-wide, from Eric W Biederman.

 9) Don't dump IFLA_VF_PORTS if netlink request didn't ask for it in
    IFLA_EXT_MASK, from David Gibson.

10) IPV6 FIB dump restart doesn't handle table changes that happen
    meanwhile, causing the code to loop forever or emit dups, fix from
    Kumar Sandararajan.

11) Memory leak on VF removal in bnx2x, from Yuval Mintz.

12) Bug fixes for new Altera TSE driver from Vince Bridgers.

13) Fix route lookup key in SCTP, from Xugeng Zhang.

14) Use BH blocking spinlocks in SLIP, as per a similar fix to CAN/SLCAN
    driver.  From Oliver Hartkopp.

15) TCP doesn't bump retransmit counters in some code paths, fix from
    Eric Dumazet.

16) Clamp delayed_ack in tcp_cubic to prevent theoretical divides by
    zero.  Fix from Liu Yu.

17) Fix locking imbalance in error paths of HHF packet scheduler, from
    John Fastabend.

18) Properly reference the transport module when vsock_core_init() runs,
    from Andy King.

19) Fix buffer overflow in cdc_ncm driver, from Bjørn Mork.

20) IP_ECN_decapsulate() doesn't see a correct SKB network header in
    ip_tunnel_rcv(), fix from Ying Cai.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (132 commits)
  net: macb: Fix race between HW and driver
  net: macb: Remove 'unlikely' optimization
  net: macb: Re-enable RX interrupt only when RX is done
  net: macb: Clear interrupt flags
  net: macb: Pass same size to DMA_UNMAP as used for DMA_MAP
  ip_tunnel: Set network header properly for IP_ECN_decapsulate()
  e1000e: Restrict MDIO Slow Mode workaround to relevant parts
  e1000e: Fix issue with link flap on 82579
  e1000e: Expand workaround for 10Mb HD throughput bug
  e1000e: Workaround for dropped packets in Gig/100 speeds on 82579
  net/mlx4_core: Don't issue PCIe speed/width checks for VFs
  net/mlx4_core: Load the Eth driver first
  net/mlx4_core: Fix slave id computation for single port VF
  net/mlx4_core: Adjust port number in qp_attach wrapper when detaching
  net: cdc_ncm: fix buffer overflow
  Altera TSE: ALTERA_TSE should depend on HAS_DMA
  vsock: Make transport the proto owner
  net: sched: lock imbalance in hhf qdisc
  net: mvmdio: Check for a valid interrupt instead of an error
  net phy: Check for aneg completion before setting state to PHY_RUNNING
  ...
2014-05-05 15:59:46 -07:00
Linus Torvalds 0384dcae2b Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "This udpate delivers:

   - A fix for dynamic interrupt allocation on x86 which is required to
     exclude the GSI interrupts from the dynamic allocatable range.

     This was detected with the newfangled tablet SoCs which have GPIOs
     and therefor allocate a range of interrupts.  The MSI allocations
     already excluded the GSI range, so we never noticed before.

   - The last missing set_irq_affinity() repair, which was delayed due
     to testing issues

   - A few bug fixes for the armada SoC interrupt controller

   - A memory allocation fix for the TI crossbar interrupt controller

   - A trivial kernel-doc warning fix"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip: irq-crossbar: Not allocating enough memory
  irqchip: armanda: Sanitize set_irq_affinity()
  genirq: x86: Ensure that dynamic irq allocation does not conflict
  linux/interrupt.h: fix new kernel-doc warnings
  irqchip: armada-370-xp: Fix releasing of MSIs
  irqchip: armada-370-xp: implement the ->check_device() msi_chip operation
  irqchip: armada-370-xp: fix invalid cast of signed value into unsigned variable
2014-05-03 08:32:48 -07:00
Linus Torvalds 98facf0e1e 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 update brings along:

   - Two fixes for long standing bugs in the hrtimer code, one which
     prevents remote enqueuing and the other preventing arbitrary delays
     after a interrupt hang was detected

   - A fix in the timer wheel which prevents math overflow

   - A fix for a long standing issue with the architected ARM timer
     related to the C3STOP mechanism.

   - A trivial compile fix for nspire SoC clocksource"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timer: Prevent overflow in apply_slack
  hrtimer: Prevent remote enqueue of leftmost timers
  hrtimer: Prevent all reprogramming if hang detected
  clocksource: nspire: Fix compiler warning
  clocksource: arch_arm_timer: Fix age-old arch timer C3STOP detection issue
2014-05-03 08:31:45 -07:00