Commit Graph

23791 Commits

Author SHA1 Message Date
Linus Torvalds 9ad1aeecdb Merge branch 'core-smp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP bootup updates from Ingo Molnar:
 "Three changes to unify/standardize some of the bootup message printing
  in kernel/smp.c between architectures"

* 'core-smp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kernel/smp: Tell the user we're bringing up secondary CPUs
  kernel/smp: Make the SMP boot message common on all arches
  kernel/smp: Define pr_fmt() for smp.c
2016-12-12 10:02:01 -08:00
Linus Torvalds 718c0ddd6a Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main RCU changes in this development cycle were:

   - Miscellaneous fixes, including a change to call_rcu()'s rcu_head
     alignment check.

   - Security-motivated list consistency checks, which are disabled by
     default behind DEBUG_LIST.

   - Torture-test updates.

   - Documentation updates, yet again just simple changes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  torture: Prevent jitter from delaying build-only runs
  torture: Remove obsolete files from rcutorture .gitignore
  rcu: Don't kick unless grace period or request
  rcu: Make expedited grace periods recheck dyntick idle state
  torture: Trace long read-side delays
  rcu: RCU_TRACE enables event tracing as well as debugfs
  rcu: Remove obsolete comment from __call_rcu()
  rcu: Remove obsolete rcu_check_callbacks() header comment
  rcu: Tighten up __call_rcu() rcu_head alignment check
  Documentation/RCU: Fix minor typo
  documentation: Present updated RCU guarantee
  bug: Avoid Kconfig warning for BUG_ON_DATA_CORRUPTION
  lib/Kconfig.debug: Fix typo in select statement
  lkdtm: Add tests for struct list corruption
  bug: Provide toggle for BUG on data corruption
  list: Split list_del() debug checking into separate function
  rculist: Consolidate DEBUG_LIST for list_add_rcu()
  list: Split list_add() debug checking into separate function
2016-12-12 09:09:54 -08:00
Vincent Guittot 6b94780e45 sched/core: Use load_avg for selecting idlest group
find_idlest_group() only compares the runnable_load_avg when looking
for the least loaded group. But on fork intensive use case like
hackbench where tasks blocked quickly after the fork, this can lead to
selecting the same CPU instead of other CPUs, which have similar
runnable load but a lower load_avg.

When the runnable_load_avg of 2 CPUs are close, we now take into
account the amount of blocked load as a 2nd selection factor. There is
now 3 zones for the runnable_load of the rq:

 - [0 .. (runnable_load - imbalance)]:
	Select the new rq which has significantly less runnable_load

 - [(runnable_load - imbalance) .. (runnable_load + imbalance)]:
	The runnable loads are close so we use load_avg to chose
	between the 2 rq

 - [(runnable_load + imbalance) .. ULONG_MAX]:
	Keep the current rq which has significantly less runnable_load

The scale factor that is currently used for comparing runnable_load,
doesn't work well with small value. As an example, the use of a
scaling factor fails as soon as this_runnable_load == 0 because we
always select local rq even if min_runnable_load is only 1, which
doesn't really make sense because they are just the same. So instead
of scaling factor, we use an absolute margin for runnable_load to
detect CPUs with similar runnable_load and we keep using scaling
factor for blocked load.

For use case like hackbench, this enable the scheduler to select
different CPUs during the fork sequence and to spread tasks across the
system.

Tests have been done on a Hikey board (ARM based octo cores) for
several kernel. The result below gives min, max, avg and stdev values
of 18 runs with each configuration.

The patches depend on the "no missing update_rq_clock()" work.

hackbench -P -g 1

         ea86cb4b76  7dc603c902  v4.8        v4.8+patches
  min    0.049         0.050         0.051       0,048
  avg    0.057         0.057(0%)     0.057(0%)   0,055(+5%)
  max    0.066         0.068         0.070       0,063
  stdev  +/-9%         +/-9%         +/-8%       +/-9%

More performance numbers here:

  https://lkml.kernel.org/r/20161203214707.GI20785@codeblueprint.co.uk

Tested-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: kernellwp@gmail.com
Cc: umgwanakikbuti@gmail.com
Cc: yuyang.du@intel.comc
Link: http://lkml.kernel.org/r/1481216215-24651-3-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-11 13:10:57 +01:00
Vincent Guittot f519a3f1c6 sched/core: Fix find_idlest_group() for fork
During fork, the utilization of a task is init once the rq has been
selected because the current utilization level of the rq is used to
set the utilization of the fork task. As the task's utilization is
still 0 at this step of the fork sequence, it doesn't make sense to
look for some spare capacity that can fit the task's utilization.
Furthermore, I can see perf regressions for the test:

   hackbench -P -g 1

because the least loaded policy is always bypassed and tasks are not
spread during fork.

With this patch and the fix below, we are back to same performances as
for v4.8. The fix below is only a temporary one used for the test
until a smarter solution is found because we can't simply remove the
test which is useful for others benchmarks

| @@ -5708,13 +5708,6 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int t
|
|	avg_cost = this_sd->avg_scan_cost;
|
| -	/*
| -	 * Due to large variance we need a large fuzz factor; hackbench in
| -	 * particularly is sensitive here.
| -	 */
| -	if ((avg_idle / 512) < avg_cost)
| -		return -1;
| -
|	time = local_clock();
|
|	for_each_cpu_wrap(cpu, sched_domain_span(sd), target, wrap) {

Tested-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: kernellwp@gmail.com
Cc: umgwanakikbuti@gmail.com
Cc: yuyang.du@intel.comc
Link: http://lkml.kernel.org/r/1481216215-24651-2-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-11 13:10:56 +01:00
Ingo Molnar 6643aab30f Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-11 13:10:40 +01:00
Ingo Molnar 6f38751510 Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-11 13:07:13 +01:00
David S. Miller 821781a9f4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-12-10 16:21:55 -05:00
Steven Rostedt (Red Hat) 1a41442864 tracing/fgraph: Have wakeup and irqsoff tracers ignore graph functions too
Currently both the wakeup and irqsoff traces do not handle set_graph_notrace
well. The ftrace infrastructure will ignore the return paths of all
functions leaving them hanging without an end:

  # echo '*spin*' > set_graph_notrace
  # cat trace
  [...]
          _raw_spin_lock() {
            preempt_count_add() {
            do_raw_spin_lock() {
          update_rq_clock();

Where the '*spin*' functions should have looked like this:

          _raw_spin_lock() {
            preempt_count_add();
            do_raw_spin_lock();
          }
          update_rq_clock();

Instead, have the wakeup and irqsoff tracers ignore the functions that are
set by the set_graph_notrace like the function_graph tracer does. Move
the logic in the function_graph tracer into a header to allow wakeup and
irqsoff tracers to use it as well.

Cc: Namhyung Kim <namhyung.kim@lge.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-12-09 09:21:35 -05:00
Steven Rostedt (Red Hat) 794de08a16 fgraph: Handle a case where a tracer ignores set_graph_notrace
Both the wakeup and irqsoff tracers can use the function graph tracer when
the display-graph option is set. The problem is that they ignore the notrace
file, and record the entry of functions that would be ignored by the
function_graph tracer. This causes the trace->depth to be recorded into the
ring buffer. The set_graph_notrace uses a trick by adding a large negative
number to the trace->depth when a graph function is to be ignored.

On trace output, the graph function uses the depth to record a stack of
functions. But since the depth is negative, it accesses the array with a
negative number and causes an out of bounds access that can cause a kernel
oops or corrupt data.

Have the print functions handle cases where a tracer still records functions
even when they are in set_graph_notrace.

Also add warnings if the depth is below zero before accessing the array.

Note, the function graph logic will still prevent the return of these
functions from being recorded, which means that they will be left hanging
without a return. For example:

   # echo '*spin*' > set_graph_notrace
   # echo 1 > options/display-graph
   # echo wakeup > current_tracer
   # cat trace
   [...]
      _raw_spin_lock() {
        preempt_count_add() {
        do_raw_spin_lock() {
      update_rq_clock();

Where it should look like:

      _raw_spin_lock() {
        preempt_count_add();
        do_raw_spin_lock();
      }
      update_rq_clock();

Cc: stable@vger.kernel.org
Cc: Namhyung Kim <namhyung.kim@lge.com>
Fixes: 29ad23b004 ("ftrace: Add set_graph_notrace filter")
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-12-09 09:19:28 -05:00
Steven Rostedt (Red Hat) 656c7f0d2d tracing: Replace kmap with copy_from_user() in trace_marker writing
Instead of using get_user_pages_fast() and kmap_atomic() when writing
to the trace_marker file, just allocate enough space on the ring buffer
directly, and write into it via copy_from_user().

Writing into the trace_marker file use to allocate a temporary buffer
to perform the copy_from_user(), as we didn't want to write into the
ring buffer if the copy failed. But as a trace_marker write is suppose
to be extremely fast, and allocating memory causes other tracepoints to
trigger, Peter Zijlstra suggested using get_user_pages_fast() and
kmap_atomic() to keep the user space pages in memory and reading it
directly. But Henrik Austad had issues with this because it required taking
the mm->mmap_sem and causing long delays with the write.

Instead, just allocate the space in the ring buffer and use
copy_from_user() directly. If it faults, return -EFAULT and write
"<faulted>" into the ring buffer.

Link: http://lkml.kernel.org/r/20161208124018.72dd0f86@gandalf.local.home

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Henrik Austad <henrik@austad.us>
Cc: Peter Zijlstra <peterz@infradead.org>
Updates: d696b58ca2 "tracing: Do not allocate buffer for trace_marker"
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-12-09 09:18:14 -05:00
Steven Rostedt (Red Hat) 9c1f6bb8c8 tracing: Allow benchmark to be enabled at early_initcall()
The trace event start up selftests fails when the trace benchmark is
enabled, because it is disabled during boot. It really only needs to be
disabled before scheduling is set up, as it creates a thread.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-12-09 09:16:15 -05:00
Steven Rostedt (Red Hat) 989a0a3d24 tracing: Have system enable return error if one of the events fail
If one of the events within a system fails to enable when "1" is written
to the system "enable" file, it should return an error. Note, some events
may still be enabled, but the user should know that something did go wrong.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-12-09 09:15:41 -05:00
Steven Rostedt (Red Hat) 1dd349ab74 tracing: Do not start benchmark on boot up
Trace events are enabled very early on boot up via the boot command line
parameter. The benchmark tool creates a new thread to perform the trace
event benchmarking. But at start up, it is called before scheduling is set
up and because it creates a new thread before the init thread is created,
this crashes the kernel.

Have the benchmark fail to register when started via the kernel command
line.

Also, since the registering of a tracepoint now can handle failure cases,
return -ENOMEM instead of warning if the thread cannot be created.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-12-09 09:14:00 -05:00
Steven Rostedt (Red Hat) 8cf868affd tracing: Have the reg function allow to fail
Some tracepoints have a registration function that gets enabled when the
tracepoint is enabled. There may be cases that the registraction function
must fail (for example, can't allocate enough memory). In this case, the
tracepoint should also fail to register, otherwise the user would not know
why the tracepoint is not working.

Cc: David Howells <dhowells@redhat.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-12-09 09:13:30 -05:00
Thomas Gleixner c029a2bec6 timekeeping: Use mul_u64_u32_shr() instead of open coding it
The resume code must deal with a clocksource delta which is potentially big
enough to overflow the 64bit mult.

Replace the open coded handling with the proper function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Parit Bhargava <prarit@redhat.com>
Cc: Laurent Vivier <lvivier@redhat.com>
Cc: "Christopher S. Hall" <christopher.s.hall@intel.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Liav Rehana <liavr@mellanox.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20161208204228.921674404@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-09 12:06:42 +01:00
Thomas Gleixner cbd99e3b28 timekeeping: Get rid of pointless typecasts
cycle_t is defined as u64, so casting it to u64 is a pointless and
confusing exercise. cycle_t should simply go away and be replaced with a
plain u64 to avoid further confusion.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Parit Bhargava <prarit@redhat.com>
Cc: Laurent Vivier <lvivier@redhat.com>
Cc: "Christopher S. Hall" <christopher.s.hall@intel.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Liav Rehana <liavr@mellanox.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20161208204228.844699737@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-09 12:06:42 +01:00
Thomas Gleixner acc89612a7 timekeeping: Make the conversion call chain consistently unsigned
Propagating a unsigned value through signed variables and functions makes
absolutely no sense and is just prone to (re)introduce subtle signed
vs. unsigned issues as happened recently.

Clean it up.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Parit Bhargava <prarit@redhat.com>
Cc: Laurent Vivier <lvivier@redhat.com>
Cc: "Christopher S. Hall" <christopher.s.hall@intel.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Liav Rehana <liavr@mellanox.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20161208204228.765843099@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-09 12:06:41 +01:00
Thomas Gleixner 9c1645727b timekeeping_Force_unsigned_clocksource_to_nanoseconds_conversion
The clocksource delta to nanoseconds conversion is using signed math, but
the delta is unsigned. This makes the conversion space smaller than
necessary and in case of a multiplication overflow the conversion can
become negative. The conversion is done with scaled math:

    s64 nsec_delta = ((s64)clkdelta * clk->mult) >> clk->shift;

Shifting a signed integer right obvioulsy preserves the sign, which has
interesting consequences:
 
 - Time jumps backwards
 
 - __iter_div_u64_rem() which is used in one of the calling code pathes
   will take forever to piecewise calculate the seconds/nanoseconds part.

This has been reported by several people with different scenarios:

David observed that when stopping a VM with a debugger:

 "It was essentially the stopped by debugger case.  I forget exactly why,
  but the guest was being explicitly stopped from outside, it wasn't just
  scheduling lag.  I think it was something in the vicinity of 10 minutes
  stopped."

 When lifting the stop the machine went dead.

The stopped by debugger case is not really interesting, but nevertheless it
would be a good thing not to die completely.

But this was also observed on a live system by Liav:

 "When the OS is too overloaded, delta will get a high enough value for the
  msb of the sum delta * tkr->mult + tkr->xtime_nsec to be set, and so
  after the shift the nsec variable will gain a value similar to
  0xffffffffff000000."

Unfortunately this has been reintroduced recently with commit 6bd58f09e1
("time: Add cycles to nanoseconds translation"). It had been fixed a year
ago already in commit 35a4933a89 ("time: Avoid signed overflow in
timekeeping_get_ns()").

Though it's not surprising that the issue has been reintroduced because the
function itself and the whole call chain uses s64 for the result and the
propagation of it. The change in this recent commit is subtle:

   s64 nsec;

-  nsec = (d * m + n) >> s:
+  nsec = d * m + n;
+  nsec >>= s;

d being type of cycle_t adds another level of obfuscation.

This wouldn't have happened if the previous change to unsigned computation
would have made the 'nsec' variable u64 right away and a follow up patch
had cleaned up the whole call chain.

There have been patches submitted which basically did a revert of the above
patch leaving everything else unchanged as signed. Back to square one. This
spawned a admittedly pointless discussion about potential users which rely
on the unsigned behaviour until someone pointed out that it had been fixed
before. The changelogs of said patches added further confusion as they made
finally false claims about the consequences for eventual users which expect
signed results.

Despite delta being cycle_t, aka. u64, it's very well possible to hand in
a signed negative value and the signed computation will happily return the
correct result. But nobody actually sat down and analyzed the code which
was added as user after the propably unintended signed conversion.

Though in sensitive code like this it's better to analyze it proper and
make sure that nothing relies on this than hunting the subtle wreckage half
a year later. After analyzing all call chains it stands that no caller can
hand in a negative value (which actually would work due to the s64 cast)
and rely on the signed math to do the right thing.

Change the conversion function to unsigned math. The conversion of all call
chains is done in a follow up patch.

This solves the starvation issue, which was caused by the negative result,
but it does not solve the underlying problem. It merily procrastinates
it. When the timekeeper update is deferred long enough that the unsigned
multiplication overflows, then time going backwards is observable again.

It does neither solve the issue of clocksources with a small counter width
which will wrap around possibly several times and cause random time stamps
to be generated. But those are usually not found on systems used for
virtualization, so this is likely a non issue.

I took the liberty to claim authorship for this simply because
analyzing all callsites and writing the changelog took substantially
more time than just making the simple s/s64/u64/ change and ignore the
rest.

Fixes: 6bd58f09e1 ("time: Add cycles to nanoseconds translation")
Reported-by: David Gibson <david@gibson.dropbear.id.au>
Reported-by: Liav Rehana <liavr@mellanox.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Parit Bhargava <prarit@redhat.com>
Cc: Laurent Vivier <lvivier@redhat.com>
Cc: "Christopher S. Hall" <christopher.s.hall@intel.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20161208204228.688545601@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-09 12:06:41 +01:00
Martin KaFai Lau 17bedab272 bpf: xdp: Allow head adjustment in XDP prog
This patch allows XDP prog to extend/remove the packet
data at the head (like adding or removing header).  It is
done by adding a new XDP helper bpf_xdp_adjust_head().

It also renames bpf_helper_changes_skb_data() to
bpf_helper_changes_pkt_data() to better reflect
that XDP prog does not work on skb.

This patch adds one "xdp_adjust_head" bit to bpf_prog for the
XDP-capable driver to check if the XDP prog requires
bpf_xdp_adjust_head() support.  The driver can then decide
to error out during XDP_SETUP_PROG.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-08 14:25:13 -05:00
Alexei Starovoitov d2a4dd37f6 bpf: fix state equivalence
Commmits 57a09bf0a4 ("bpf: Detect identical PTR_TO_MAP_VALUE_OR_NULL registers")
and 484611357c ("bpf: allow access into map value arrays") by themselves
are correct, but in combination they make state equivalence ignore 'id' field
of the register state which can lead to accepting invalid program.

Fixes: 57a09bf0a4 ("bpf: Detect identical PTR_TO_MAP_VALUE_OR_NULL registers")
Fixes: 484611357c ("bpf: allow access into map value arrays")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-08 13:31:11 -05:00
Oleg Nesterov 8fb9dcbdc3 kthread: Don't abuse kthread_create_on_cpu() in __kthread_create_worker()
kthread_create_on_cpu() sets KTHREAD_IS_PER_CPU and kthread->cpu, this
only makes sense if this kthread can be parked/unparked by cpuhp code.
kthread workers never call kthread_parkme() so this has no effect.

Change __kthread_create_worker() to simply call kthread_bind(task, cpu).
The very fact that kthread_create_on_cpu() doesn't accept a generic fmt
shows that it should not be used outside of smpboot.c.

Now, the only reason we can not unexport this helper and move it into
smpboot.c is that it sets kthread->cpu and struct kthread is not exported.
And the only reason we can not kill kthread->cpu is that kthread_unpark()
is used by drivers/gpu/drm/amd/scheduler/gpu_scheduler.c and thus we can
not turn _unpark into kthread_unpark(struct smp_hotplug_thread *, cpu).

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Chunming Zhou <David1.Zhou@amd.com>
Cc: Roman Pen <roman.penyaev@profitbricks.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20161129175110.GA5342@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-08 14:36:20 +01:00
Oleg Nesterov cf380a4a96 kthread: Don't use to_live_kthread() in kthread_[un]park()
Now that to_kthread() is always validm change kthread_park() and
kthread_unpark() to use it and kill to_live_kthread().

The conversion of kthread_unpark() is trivial. If KTHREAD_IS_PARKED is set
then the task has called complete(&self->parked) and there the function
cannot race against a concurrent kthread_stop() and exit.

kthread_park() is more tricky, because its semantics are not well
defined. It returns -ENOSYS if the thread exited but this can never happen
and as Roman pointed out kthread_park() can obviously block forever if it
would race with the exiting kthread.

The usage of kthread_park() in cpuhp code (cpu.c, smpboot.c, stop_machine.c)
is fine. It can never see an exiting/exited kthread, smpboot_destroy_threads()
clears *ht->store, smpboot_park_thread() checks it is not NULL under the same
smpboot_threads_lock. cpuhp_threads and cpu_stop_threads never exit, so other
callers are fine too.

But it has two more users:

- watchdog_park_threads():

  The code is actually correct, get_online_cpus() ensures that
  kthread_park() can't race with itself (note that kthread_park() can't
  handle this race correctly), but it should not use kthread_park()
  directly.

- drivers/gpu/drm/amd/scheduler/gpu_scheduler.c should not use
  kthread_park() either.

  kthread_park() must not be called after amd_sched_fini() which does
  kthread_stop(), otherwise even to_live_kthread() is not safe because
  task_struct can be already freed and sched->thread can point to nowhere.

The usage of kthread_park/unpark should either be restricted to core code
which is properly protected against the exit race or made more robust so it
is safe to use it in drivers.

To catch eventual exit issues, add a WARN_ON(PF_EXITING) for now.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chunming Zhou <David1.Zhou@amd.com>
Cc: Roman Pen <roman.penyaev@profitbricks.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20161129175107.GA5339@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-08 14:36:19 +01:00
Oleg Nesterov efb29fbfa5 kthread: Don't use to_live_kthread() in kthread_stop()
kthread_stop() had to use to_live_kthread() simply because it was not
possible to access kthread->exited after the exiting task clears
task_struct->vfork_done. Now that to_kthread() is always valid,
wake_up_process() + wait_for_completion() can be done
ununconditionally. It's not an issue anymore if the task has already issued
complete_vfork_done() or died.

The exiting task can get the spurious wakeup after mm_release() but this is
possible without this change too and is fine; do_task_dead() ensures that
this can't make any harm.

As a further enhancement this could be converted to task_work_add() later,
so ->vfork_done can be avoided completely.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chunming Zhou <David1.Zhou@amd.com>
Cc: Roman Pen <roman.penyaev@profitbricks.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20161129175103.GA5336@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-08 14:36:19 +01:00
Oleg Nesterov eff9662547 Revert "kthread: Pin the stack via try_get_task_stack()/put_task_stack() in to_live_kthread() function"
This reverts commit 23196f2e5f.

Now that struct kthread is kmalloc'ed and not longer on the task stack
there is no need anymore to pin the stack.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chunming Zhou <David1.Zhou@amd.com>
Cc: Roman Pen <roman.penyaev@profitbricks.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20161129175100.GA5333@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-08 14:36:18 +01:00
Oleg Nesterov 1da5c46fa9 kthread: Make struct kthread kmalloc'ed
commit 23196f2e5f "kthread: Pin the stack via try_get_task_stack() /
put_task_stack() in to_live_kthread() function" is a workaround for the
fragile design of struct kthread being allocated on the task stack.

struct kthread in its current form should be removed, but this needs
cleanups outside of kthread.c.

As a first step move struct kthread away from the task stack by making it
kmalloc'ed. This allows to access kthread.exited without the magic of
trying to pin task stack and the try logic in to_live_kthread().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chunming Zhou <David1.Zhou@amd.com>
Cc: Roman Pen <roman.penyaev@profitbricks.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20161129175057.GA5330@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-08 14:36:18 +01:00
Michal Hocko 777c6e0dae hotplug: Make register and unregister notifier API symmetric
Yu Zhao has noticed that __unregister_cpu_notifier only unregisters its
notifiers when HOTPLUG_CPU=y while the registration might succeed even
when HOTPLUG_CPU=n if MODULE is enabled. This means that e.g. zswap
might keep a stale notifier on the list on the manual clean up during
the pool tear down and thus corrupt the list. Resulting in the following

[  144.964346] BUG: unable to handle kernel paging request at ffff880658a2be78
[  144.971337] IP: [<ffffffffa290b00b>] raw_notifier_chain_register+0x1b/0x40
<snipped>
[  145.122628] Call Trace:
[  145.125086]  [<ffffffffa28e5cf8>] __register_cpu_notifier+0x18/0x20
[  145.131350]  [<ffffffffa2a5dd73>] zswap_pool_create+0x273/0x400
[  145.137268]  [<ffffffffa2a5e0fc>] __zswap_param_set+0x1fc/0x300
[  145.143188]  [<ffffffffa2944c1d>] ? trace_hardirqs_on+0xd/0x10
[  145.149018]  [<ffffffffa2908798>] ? kernel_param_lock+0x28/0x30
[  145.154940]  [<ffffffffa2a3e8cf>] ? __might_fault+0x4f/0xa0
[  145.160511]  [<ffffffffa2a5e237>] zswap_compressor_param_set+0x17/0x20
[  145.167035]  [<ffffffffa2908d3c>] param_attr_store+0x5c/0xb0
[  145.172694]  [<ffffffffa290848d>] module_attr_store+0x1d/0x30
[  145.178443]  [<ffffffffa2b2b41f>] sysfs_kf_write+0x4f/0x70
[  145.183925]  [<ffffffffa2b2a5b9>] kernfs_fop_write+0x149/0x180
[  145.189761]  [<ffffffffa2a99248>] __vfs_write+0x18/0x40
[  145.194982]  [<ffffffffa2a9a412>] vfs_write+0xb2/0x1a0
[  145.200122]  [<ffffffffa2a9a732>] SyS_write+0x52/0xa0
[  145.205177]  [<ffffffffa2ff4d97>] entry_SYSCALL_64_fastpath+0x12/0x17

This can be even triggered manually by changing
/sys/module/zswap/parameters/compressor multiple times.

Fix this issue by making unregister APIs symmetric to the register so
there are no surprises.

Fixes: 47e627bc8c ("[PATCH] hotplug: Allow modules to use the cpu hotplug notifiers even if !CONFIG_HOTPLUG_CPU")
Reported-and-tested-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Streetman <ddstreet@ieee.org>
Link: http://lkml.kernel.org/r/20161207135438.4310-1-mhocko@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-08 10:08:41 +01:00
Kefeng Wang 166ad0e1e2 kcov: add missing #include <linux/sched.h>
In __sanitizer_cov_trace_pc we use task_struct and fields within it, but
as we haven't included <linux/sched.h>, it is not guaranteed to be
defined.  While we usually happen to acquire the definition through a
transitive include, this is fragile (and hasn't been true in the past,
causing issues with backports).

Include <linux/sched.h> to avoid any fragility.

[mark.rutland@arm.com: rewrote changelog]
Link: http://lkml.kernel.org/r/1481007384-27529-1-git-send-email-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-07 17:10:00 -08:00
Linus Torvalds 68f5503bdc Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Ingo Molnar:
 "An autogroup nice level adjustment bug fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/autogroup: Fix 64-bit kernel nice level adjustment
2016-12-07 11:35:55 -08:00
Linus Torvalds bf7f1c7e2f Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "A bogus warning fix, a counter width handling fix affecting certain
  machines, plus a oneliner hw-enablement patch for Knights Mill CPUs"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Remove invalid warning from list_update_cgroup_even()t
  perf/x86: Fix full width counter, counter overflow
  perf/x86/intel: Enable C-state residency events for Knights Mill
2016-12-07 11:32:19 -08:00
Linus Torvalds 5b43f97f3f Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Two rtmutex race fixes (which miraculously never triggered, that we
  know of), plus two lockdep printk formatting regression fixes"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep: Fix report formatting
  locking/rtmutex: Use READ_ONCE() in rt_mutex_owner()
  locking/rtmutex: Prevent dequeue vs. unlock race
  locking/selftest: Fix output since KERN_CONT changes
2016-12-07 11:27:33 -08:00
Daniel Borkmann ef0915cacd bpf: fix loading of BPF_MAXINSNS sized programs
General assumption is that single program can hold up to BPF_MAXINSNS,
that is, 4096 number of instructions. It is the case with cBPF and
that limit was carried over to eBPF. When recently testing digest, I
noticed that it's actually not possible to feed 4096 instructions
via bpf(2).

The check for > BPF_MAXINSNS was added back then to bpf_check() in
cbd3570086 ("bpf: verifier (add ability to receive verification log)").
However, 09756af468 ("bpf: expand BPF syscall with program load/unload")
added yet another check that comes before that into bpf_prog_load(),
but this time bails out already in case of >= BPF_MAXINSNS.

Fix it up and perform the check early in bpf_prog_load(), so we can drop
the second one in bpf_check(). It makes sense, because also a 0 insn
program is useless and we don't want to waste any resources doing work
up to bpf_check() point. The existing bpf(2) man page documents E2BIG
as the official error for such cases, so just stick with it as well.

Fixes: 09756af468 ("bpf: expand BPF syscall with program load/unload")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-07 13:16:04 -05:00
Murali Karicheri 5304121ada clocksource: export the clocks_calc_mult_shift to use by timestamp code
The CPSW CPTS driver is capable of doing timestamping on tx/rx packets and
requires to know mult and shift factors for timestamp conversion from raw
value to nanoseconds (ptp clock). Now these mult and shift factors are
calculated manually and provided through DT, which makes very hard to
support of a lot number of platforms, especially if CPTS refclk is not the
same for some kind of boards and depends on efuse settings (Keystone 2
platforms). Hence, export clocks_calc_mult_shift() to allow drivers like
CPSW CPTS (and other ptp drivesr) to benefit from automaitc calculation of
mult and shift factors.

Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-07 11:13:48 -05:00
Sebastian Andrzej Siewior b18cc3de00 tracing/rb: Init the CPU mask on allocation
Before commit b32614c034 ("tracing/rb: Convert to hotplug state machine")
the allocated cpumask was initialized to the mask of online or possible
CPUs. After the CPU hotplug changes the buffer initialization moved to
trace_rb_cpu_prepare() but the cpumask is allocated with alloc_cpumask()
and therefor has random content. As a consequence the cpu buffers are not
initialized and a later access dereferences a NULL pointer.

Use zalloc_cpumask() instead so trace_rb_cpu_prepare() initializes the
buffers properly.

Fixes: b32614c034 ("tracing/rb: Convert to hotplug state machine")
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: rostedt@goodmis.org
Link: http://lkml.kernel.org/r/20161207133133.hzkcqfllxcdi3joz@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-07 14:36:21 +01:00
Dmitry Vyukov f943fe0faf lockdep: Fix report formatting
Since commit:

  4bcc595ccd ("printk: reinstate KERN_CONT for printing continuation lines")

printk() requires KERN_CONT to continue log messages. Lots of printk()
in lockdep.c and print_ip_sym() don't have it. As the result lockdep
reports are completely messed up.

Add missing KERN_CONT and inline print_ip_sym() where necessary.

Example of a messed up report:

  0-rc5+ #41 Not tainted
  -------------------------------------------------------
  syz-executor0/5036 is trying to acquire lock:
   (
  rtnl_mutex
  ){+.+.+.}
  , at:
  [<ffffffff86b3d6ac>] rtnl_lock+0x1c/0x20
  but task is already holding lock:
   (
  &net->packet.sklist_lock
  ){+.+...}
  , at:
  [<ffffffff873541a6>] packet_diag_dump+0x1a6/0x1920
  which lock already depends on the new lock.
  the existing dependency chain (in reverse order) is:
  -> #3
   (
  &net->packet.sklist_lock
  +.+...}
  ...

Without this patch all scripts that parse kernel bug reports are broken.

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andreyknvl@google.com
Cc: aryabinin@virtuozzo.com
Cc: joe@perches.com
Cc: syzkaller@googlegroups.com
Link: http://lkml.kernel.org/r/1480343083-48731-1-git-send-email-dvyukov@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-06 10:40:08 +01:00
David Carrillo-Cisneros 8fc31ce889 perf/core: Remove invalid warning from list_update_cgroup_even()t
The warning introduced in commit:

  864c2357ca ("perf/core: Do not set cpuctx->cgrp for unscheduled cgroups")

assumed that a cgroup switch always precedes list_del_event. This is
not the case. Remove warning.

Make sure that cpuctx->cgrp is NULL until a cgroup event is sched in
or ctx->nr_cgroups == 0.

Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V Shankar <ravi.v.shankar@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1480841177-27299-1-git-send-email-davidcc@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-06 09:44:29 +01:00
Al Viro 8bd107633b audit_log_{name,link_denied}: constify struct path
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-05 19:00:38 -05:00
Al Viro 3cd5eca8d7 fsnotify: constify 'data' passed to ->handle_event()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-05 18:58:31 -05:00
Daniel Borkmann 7bd509e311 bpf: add prog_digest and expose it via fdinfo/netlink
When loading a BPF program via bpf(2), calculate the digest over
the program's instruction stream and store it in struct bpf_prog's
digest member. This is done at a point in time before any instructions
are rewritten by the verifier. Any unstable map file descriptor
number part of the imm field will be zeroed for the hash.

fdinfo example output for progs:

  # cat /proc/1590/fdinfo/5
  pos:          0
  flags:        02000002
  mnt_id:       11
  prog_type:    1
  prog_jited:   1
  prog_digest:  b27e8b06da22707513aa97363dfb11c7c3675d28
  memlock:      4096

When programs are pinned and retrieved by an ELF loader, the loader
can check the program's digest through fdinfo and compare it against
one that was generated over the ELF file's program section to see
if the program needs to be reloaded. Furthermore, this can also be
exposed through other means such as netlink in case of a tc cls/act
dump (or xdp in future), but also through tracepoints or other
facilities to identify the program. Other than that, the digest can
also serve as a base name for the work in progress kallsyms support
of programs. The digest doesn't depend/select the crypto layer, since
we need to keep dependencies to a minimum. iproute2 will get support
for this facility.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-05 15:33:11 -05:00
Al Viro cbbd26b8b1 [iov_iter] new primitives - copy_from_iter_full() and friends
copy_from_iter_full(), copy_from_iter_full_nocache() and
csum_and_copy_from_iter_full() - counterparts of copy_from_iter()
et.al., advancing iterator only in case of successful full copy
and returning whether it had been successful or not.

Convert some obvious users.  *NOTE* - do not blindly assume that
something is a good candidate for those unless you are sure that
not advancing iov_iter in failure case is the right thing in
this case.  Anything that does short read/short write kind of
stuff (or is in a loop, etc.) is unlikely to be a good one.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-05 14:33:36 -05:00
Gianluca Borello 3c839744b3 bpf: Preserve const register type on const OR alu ops
Occasionally, clang (e.g. version 3.8.1) translates a sum between two
constant operands using a BPF_OR instead of a BPF_ADD. The verifier is
currently not handling this scenario, and the destination register type
becomes UNKNOWN_VALUE even if it's still storing a constant. As a result,
the destination register cannot be used as argument to a helper function
expecting a ARG_CONST_STACK_*, limiting some use cases.

Modify the verifier to handle this case, and add a few tests to make sure
all combinations are supported, and stack boundaries are still verified
even with BPF_OR.

Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-05 13:40:05 -05:00
Al Viro 450630975d don't open-code file_inode()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-04 18:29:28 -05:00
David S. Miller 2745529ac7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Couple conflicts resolved here:

1) In the MACB driver, a bug fix to properly initialize the
   RX tail pointer properly overlapped with some changes
   to support variable sized rings.

2) In XGBE we had a "CONFIG_PM" --> "CONFIG_PM_SLEEP" fix
   overlapping with a reorganization of the driver to support
   ACPI, OF, as well as PCI variants of the chip.

3) In 'net' we had several probe error path bug fixes to the
   stmmac driver, meanwhile a lot of this code was cleaned up
   and reorganized in 'net-next'.

4) The cls_flower classifier obtained a helper function in
   'net-next' called __fl_delete() and this overlapped with
   Daniel Borkamann's bug fix to use RCU for object destruction
   in 'net'.  It also overlapped with Jiri's change to guard
   the rhashtable_remove_fast() call with a check against
   tc_skip_sw().

5) In mlx4, a revert bug fix in 'net' overlapped with some
   unrelated changes in 'net-next'.

6) In geneve, a stale header pointer after pskb_expand_head()
   bug fix in 'net' overlapped with a large reorganization of
   the same code in 'net-next'.  Since the 'net-next' code no
   longer had the bug in question, there was nothing to do
   other than to simply take the 'net-next' hunks.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03 12:29:53 -05:00
Linus Torvalds 8bca927f13 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Lots more phydev and probe error path leaks in various drivers by
    Johan Hovold.

 2) Fix race in packet_set_ring(), from Philip Pettersson.

 3) Use after free in dccp_invalid_packet(), from Eric Dumazet.

 4) Signnedness overflow in SO_{SND,RCV}BUFFORCE, also from Eric
    Dumazet.

 5) When tunneling between ipv4 and ipv6 we can be left with the wrong
    skb->protocol value as we enter the IPSEC engine and this causes all
    kinds of problems. Set it before the output path does any
    dst_output() calls, from Eli Cooper.

 6) bcmgenet uses wrong device struct pointer in DMA API calls, fix from
    Florian Fainelli.

 7) Various netfilter nat bug fixes from FLorian Westphal.

 8) Fix memory leak in ipvlan_link_new(), from Gao Feng.

 9) Locking fixes, particularly wrt. socket lookups, in l2tp from
    Guillaume Nault.

10) Avoid invoking rhash teardowns in atomic context by moving netlink
    cb->done() dump completion from a worker thread. Fix from Herbert
    Xu.

11) Buffer refcount problems in tun and macvtap on errors, from Jason
    Wang.

12) We don't set Kconfig symbol DEFAULT_TCP_CONG properly when the user
    selects BBR. Fix from Julian Wollrath.

13) Fix deadlock in transmit path on altera TSE driver, from Lino
    Sanfilippo.

14) Fix unbalanced reference counting in dsa_switch_tree, from Nikita
    Yushchenko.

15) tc_tunnel_key needs to be properly exported to userspace via uapi,
    fix from Roi Dayan.

16) rds_tcp_init_net() doesn't unregister notifier in error path, fix
    from Sowmini Varadhan.

17) Stale packet header pointer access after pskb_expand_head() in
    genenve driver, fix from Sabrina Dubroca.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (103 commits)
  net: avoid signed overflows for SO_{SND|RCV}BUFFORCE
  geneve: avoid use-after-free of skb->data
  tipc: check minimum bearer MTU
  net: renesas: ravb: unintialized return value
  sh_eth: remove unchecked interrupts for RZ/A1
  net: bcmgenet: Utilize correct struct device for all DMA operations
  NET: usb: qmi_wwan: add support for Telit LE922A PID 0x1040
  cdc_ether: Fix handling connection notification
  ip6_offload: check segs for NULL in ipv6_gso_segment.
  RDS: TCP: unregister_netdevice_notifier() in error path of rds_tcp_init_net
  Revert: "ip6_tunnel: Update skb->protocol to ETH_P_IPV6 in ip6_tnl_xmit()"
  ipv6: Set skb->protocol properly for local output
  ipv4: Set skb->protocol properly for local output
  packet: fix race condition in packet_set_ring
  net: ethernet: altera: TSE: do not use tx queue lock in tx completion handler
  net: ethernet: altera: TSE: Remove unneeded dma sync for tx buffers
  net: ethernet: stmmac: fix of-node and fixed-link-phydev leaks
  net: ethernet: stmmac: platform: fix outdated function header
  net: ethernet: stmmac: dwmac-meson8b: fix probe error path
  net: ethernet: stmmac: dwmac-generic: fix probe error path
  ...
2016-12-02 11:45:27 -08:00
David Ahern 6102365876 bpf: Add new cgroup attach type to enable sock modifications
Add new cgroup based program type, BPF_PROG_TYPE_CGROUP_SOCK. Similar to
BPF_PROG_TYPE_CGROUP_SKB programs can be attached to a cgroup and run
any time a process in the cgroup opens an AF_INET or AF_INET6 socket.
Currently only sk_bound_dev_if is exported to userspace for modification
by a bpf program.

This allows a cgroup to be configured such that AF_INET{6} sockets opened
by processes are automatically bound to a specific device. In turn, this
enables the running of programs that do not support SO_BINDTODEVICE in a
specific VRF context / L3 domain.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 13:46:08 -05:00
David Ahern b2cd12574a bpf: Refactor cgroups code in prep for new type
Code move and rename only; no functional change intended.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 13:44:56 -05:00
Thomas Graf 3a0af8fd61 bpf: BPF for lightweight tunnel infrastructure
Registers new BPF program types which correspond to the LWT hooks:
  - BPF_PROG_TYPE_LWT_IN   => dst_input()
  - BPF_PROG_TYPE_LWT_OUT  => dst_output()
  - BPF_PROG_TYPE_LWT_XMIT => lwtunnel_xmit()

The separate program types are required to differentiate between the
capabilities each LWT hook allows:

 * Programs attached to dst_input() or dst_output() are restricted and
   may only read the data of an skb. This prevent modification and
   possible invalidation of already validated packet headers on receive
   and the construction of illegal headers while the IP headers are
   still being assembled.

 * Programs attached to lwtunnel_xmit() are allowed to modify packet
   content as well as prepending an L2 header via a newly introduced
   helper bpf_skb_change_head(). This is safe as lwtunnel_xmit() is
   invoked after the IP header has been assembled completely.

All BPF programs receive an skb with L3 headers attached and may return
one of the following error codes:

 BPF_OK - Continue routing as per nexthop
 BPF_DROP - Drop skb and return EPERM
 BPF_REDIRECT - Redirect skb to device as per redirect() helper.
                (Only valid in lwtunnel_xmit() context)

The return codes are binary compatible with their TC_ACT_
relatives to ease compatibility.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 10:51:49 -05:00
Thomas Gleixner 84d82ec5b9 locking/rtmutex: Explain locking rules for rt_mutex_proxy_unlock()/init_proxy_locked()
While debugging the unlock vs. dequeue race which resulted in state
corruption of futexes the lockless nature of rt_mutex_proxy_unlock()
caused some confusion.

Add commentry to explain why it is safe to do this lockless. Add matching
comments to rt_mutex_init_proxy_locked() for completeness sake.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20161130210030.591941927@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-02 11:13:57 +01:00
Thomas Gleixner b5016e8203 locking/rtmutex: Get rid of RT_MUTEX_OWNER_MASKALL
This is a left over from the original rtmutex implementation which used
both bit0 and bit1 in the owner pointer. Commit:

  8161239a8b ("rtmutex: Simplify PI algorithm and make highest prio task get lock")

... removed the usage of bit1, but kept the extra mask around. This is
confusing at best.

Remove it and just use RT_MUTEX_HAS_WAITERS for the masking.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20161130210030.509567906@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-02 11:13:57 +01:00
Ingo Molnar 1b95b1a06c Merge branch 'locking/urgent' into locking/core, to pick up dependent fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-02 11:13:44 +01:00
Thomas Gleixner 1be5d4fa0a locking/rtmutex: Use READ_ONCE() in rt_mutex_owner()
While debugging the rtmutex unlock vs. dequeue race Will suggested to use
READ_ONCE() in rt_mutex_owner() as it might race against the
cmpxchg_release() in unlock_rt_mutex_safe().

Will: "It's a minor thing which will most likely not matter in practice"

Careful search did not unearth an actual problem in todays code, but it's
better to be safe than surprised.

Suggested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20161130210030.431379999@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-02 11:13:26 +01:00
Thomas Gleixner dbb26055de locking/rtmutex: Prevent dequeue vs. unlock race
David reported a futex/rtmutex state corruption. It's caused by the
following problem:

CPU0		CPU1		CPU2

l->owner=T1
		rt_mutex_lock(l)
		lock(l->wait_lock)
		l->owner = T1 | HAS_WAITERS;
		enqueue(T2)
		boost()
		  unlock(l->wait_lock)
		schedule()

				rt_mutex_lock(l)
				lock(l->wait_lock)
				l->owner = T1 | HAS_WAITERS;
				enqueue(T3)
				boost()
				  unlock(l->wait_lock)
				schedule()
		signal(->T2)	signal(->T3)
		lock(l->wait_lock)
		dequeue(T2)
		deboost()
		  unlock(l->wait_lock)
				lock(l->wait_lock)
				dequeue(T3)
				  ===> wait list is now empty
				deboost()
				 unlock(l->wait_lock)
		lock(l->wait_lock)
		fixup_rt_mutex_waiters()
		  if (wait_list_empty(l)) {
		    owner = l->owner & ~HAS_WAITERS;
		    l->owner = owner
		     ==> l->owner = T1
		  }

				lock(l->wait_lock)
rt_mutex_unlock(l)		fixup_rt_mutex_waiters()
				  if (wait_list_empty(l)) {
				    owner = l->owner & ~HAS_WAITERS;
cmpxchg(l->owner, T1, NULL)
 ===> Success (l->owner = NULL)
				    l->owner = owner
				     ==> l->owner = T1
				  }

That means the problem is caused by fixup_rt_mutex_waiters() which does the
RMW to clear the waiters bit unconditionally when there are no waiters in
the rtmutexes rbtree.

This can be fatal: A concurrent unlock can release the rtmutex in the
fastpath because the waiters bit is not set. If the cmpxchg() gets in the
middle of the RMW operation then the previous owner, which just unlocked
the rtmutex is set as the owner again when the write takes place after the
successfull cmpxchg().

The solution is rather trivial: verify that the owner member of the rtmutex
has the waiters bit set before clearing it. This does not require a
cmpxchg() or other atomic operations because the waiters bit can only be
set and cleared with the rtmutex wait_lock held. It's also safe against the
fast path unlock attempt. The unlock attempt via cmpxchg() will either see
the bit set and take the slowpath or see the bit cleared and release it
atomically in the fastpath.

It's remarkable that the test program provided by David triggers on ARM64
and MIPS64 really quick, but it refuses to reproduce on x86-64, while the
problem exists there as well. That refusal might explain that this got not
discovered earlier despite the bug existing from day one of the rtmutex
implementation more than 10 years ago.

Thanks to David for meticulously instrumenting the code and providing the
information which allowed to decode this subtle problem.

Reported-by: David Daney <ddaney@caviumnetworks.com>
Tested-by: David Daney <david.daney@cavium.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@vger.kernel.org
Fixes: 23f78d4a03 ("[PATCH] pi-futex: rt mutex core")
Link: http://lkml.kernel.org/r/20161130210030.351136722@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-02 11:13:26 +01:00
Sebastian Andrzej Siewior b32614c034 tracing/rb: Convert to hotplug state machine
Install the callbacks via the state machine. The notifier in struct
ring_buffer is replaced by the multi instance interface.  Upon
__ring_buffer_alloc() invocation, cpuhp_state_add_instance() will invoke
the trace_rb_cpu_prepare() on each CPU.

This callback may now fail. This means __ring_buffer_alloc() will fail and
cleanup (like previously) and during a CPU up event this failure will not
allow the CPU to come up.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20161126231350.10321-7-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-02 00:52:34 +01:00
WANG Cong 6060298272 audit: remove useless synchronize_net()
netlink kernel socket is protected by refcount, not RCU.
Its rcv path is neither protected by RCU. So the synchronize_net()
is just pointless.

Cc: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-01 11:29:02 -05:00
Baolin Wang 4a057549d6 alarmtimer: Add tracepoints for alarm timers
Alarm timers are one of the mechanisms to wake up a system from suspend,
but there exist no tracepoints to analyse which process/thread armed an
alarmtimer.

Add tracepoints for start/cancel/expire of individual alarm timers and one
for tracing the suspend time decision when to resume the system.

The following trace excerpt illustrates the new mechanism:

Binder:3292_2-3304  [000] d..2   149.981123: alarmtimer_cancel:
alarmtimer:ffffffc1319a7800 type:REALTIME
expires:1325463120000000000 now:1325376810370370245

Binder:3292_2-3304  [000] d..2   149.981136: alarmtimer_start:
alarmtimer:ffffffc1319a7800 type:REALTIME
expires:1325376840000000000 now:1325376810370384591

Binder:3292_9-3953  [000] d..2   150.212991: alarmtimer_cancel:
alarmtimer:ffffffc1319a5a00 type:BOOTTIME
expires:179552000000 now:150154008122

Binder:3292_9-3953  [000] d..2   150.213006: alarmtimer_start:
alarmtimer:ffffffc1319a5a00 type:BOOTTIME
expires:179551000000 now:150154025622

system_server-3000  [002] ...1  162.701940: alarmtimer_suspend:
alarmtimer type:REALTIME expires:1325376840000000000

The wakeup time which is selected at suspend time allows to map it back to
the task arming the timer: Binder:3292_2.

[ tglx: Store alarm timer expiry time instead of some useless RTC relative
  	information, add proper type information for wakeups which are
  	handled via the clock_nanosleep/freezer and massage the changelog. ]

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Link: http://lkml.kernel.org/r/1480372524-15181-5-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-01 14:45:08 +01:00
Rafael J. Wysocki 4e28ec3d5f Merge back earlier cpuidle material for v4.10. 2016-12-01 14:39:51 +01:00
Josef Bacik e2d2afe15e bpf: fix states equal logic for varlen access
If we have a branch that looks something like this

int foo = map->value;
if (condition) {
  foo += blah;
} else {
  foo = bar;
}
map->array[foo] = baz;

We will incorrectly assume that the !condition branch is equal to the condition
branch as the register for foo will be UNKNOWN_VALUE in both cases.  We need to
adjust this logic to only do this if we didn't do a varlen access after we
processed the !condition branch, otherwise we have different ranges and need to
check the other branch as well.

Fixes: 484611357c ("bpf: allow access into map value arrays")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30 14:50:52 -05:00
Thiago Jung Bauermann e2e806f9e4 kexec_file: Factor out kexec_locate_mem_hole from kexec_add_buffer.
kexec_locate_mem_hole will be used by the PowerPC kexec_file_load
implementation to find free memory for the purgatory stack.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-30 23:15:01 +11:00
Thiago Jung Bauermann ec2b9bfaac kexec_file: Change kexec_add_buffer to take kexec_buf as argument.
This is done to simplify the kexec_add_buffer argument list.
Adapt all callers to set up a kexec_buf to pass to kexec_add_buffer.

In addition, change the type of kexec_buf.buffer from char * to void *.
There is no particular reason for it to be a char *, and the change
allows us to get rid of 3 existing casts to char * in the code.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-30 23:14:59 +11:00
Thiago Jung Bauermann 60fe3910bb kexec_file: Allow arch-specific memory walking for kexec_add_buffer
Allow architectures to specify a different memory walking function for
kexec_add_buffer. x86 uses iomem to track reserved memory ranges, but
PowerPC uses the memblock subsystem.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-30 23:14:57 +11:00
Peter Zijlstra f8319483f5 locking/lockdep: Provide a type check for lock_is_held
Christoph requested lockdep_assert_held() variants that distinguish
between held-for-read or held-for-write.

Provide:

  int lock_is_held_type(struct lockdep_map *lock, int read)

which takes the same argument as lock_acquire(.read) and matches it to
the held_lock instance.

Use of this function should be gated by the debug_locks variable. When
that is 0 the return value of the lock_is_held_type() function is
undefined. This is done to allow both negative and positive tests for
holding locks.

By default we provide (positive) lockdep_assert_held{,_exclusive,_read}()
macros.

Requested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-11-30 14:32:25 +11:00
Daniel Mack 01ae87eab5 bpf: cgroup: fix documentation of __cgroup_bpf_update()
There's a 'not' missing in one paragraph. Add it.

Fixes: 3007098494 ("cgroup: add support for eBPF programs")
Signed-off-by: Daniel Mack <daniel@zonque.org>
Reported-by: Rami Rosen <roszenrami@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-29 19:50:59 -05:00
Linus Torvalds faaae2a581 Re-enable CONFIG_MODVERSIONS in a slightly weaker form
This enables CONFIG_MODVERSIONS again, but allows for missing symbol CRC
information in order to work around the issue that newer binutils
versions seem to occasionally drop the CRC on the floor.  binutils 2.26
seems to work fine, while binutils 2.27 seems to break MODVERSIONS of
symbols that have been defined in assembler files.

[ We've had random missing CRC's before - it may be an old problem that
  just is now reliably triggered with the weak asm symbols and a new
  version of binutils ]

Some day I really do want to remove MODVERSIONS entirely.  Sadly, today
does not appear to be that day: Debian people apparently do want the
option to enable MODVERSIONS to make it easier to have external modules
across kernel versions, and this seems to be a fairly minimal fix for
the annoying problem.

Cc: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-29 16:01:30 -08:00
Richard Guy Briggs 8fae477056 audit: add support for session ID user filter
Define AUDIT_SESSIONID in the uapi and add support for specifying user
filters based on the session ID.  Also add the new session ID filter
to the feature bitmap so userspace knows it is available.

https://github.com/linux-audit/audit-kernel/issues/4
RFE: add a session ID filter to the kernel's user filter

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: combine multiple patches from Richard into this one]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-11-29 15:10:12 -05:00
Joel Fernandes 80ec355210 trace: Add an option for boot clock as trace clock
Unlike monotonic clock, boot clock as a trace clock will account for
time spent in suspend useful for tracing suspend/resume. This uses
earlier introduced infrastructure for using the fast boot clock.

Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Link: http://lkml.kernel.org/r/1480372524-15181-7-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-29 18:02:59 +01:00
Joel Fernandes 948a5312f4 timekeeping: Add a fast and NMI safe boot clock
This boot clock can be used as a tracing clock and will account for
suspend time.

To keep it NMI safe since we're accessing from tracing, we're not using a
separate timekeeper with updates to monotonic clock and boot offset
protected with seqlocks. This has the following minor side effects:

(1) Its possible that a timestamp be taken after the boot offset is updated
but before the timekeeper is updated. If this happens, the new boot offset
is added to the old timekeeping making the clock appear to update slightly
earlier:
   CPU 0                                        CPU 1
   timekeeping_inject_sleeptime64()
   __timekeeping_inject_sleeptime(tk, delta);
                                                timestamp();
   timekeeping_update(tk, TK_CLEAR_NTP...);

(2) On 32-bit systems, the 64-bit boot offset (tk->offs_boot) may be
partially updated.  Since the tk->offs_boot update is a rare event, this
should be a rare occurrence which postprocessing should be able to handle.

Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1480372524-15181-6-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-29 18:02:59 +01:00
Peter Zijlstra c1de45ca83 sched/idle: Add support for tasks that inject idle
Idle injection drivers such as Intel powerclamp and ACPI PAD drivers use
realtime tasks to take control of CPU then inject idle. There are two
issues with this approach:

 1. Low efficiency: injected idle task is treated as busy so sched ticks
    do not stop during injected idle period, the result of these
    unwanted wakeups can be ~20% loss in power savings.

 2. Idle accounting: injected idle time is presented to user as busy.

This patch addresses the issues by introducing a new PF_IDLE flag which
allows any given task to be treated as idle task while the flag is set.
Therefore, idle injection tasks can run through the normal flow of NOHZ
idle enter/exit to get the correct accounting as well as tick stop when
possible.

The implication is that idle task is then no longer limited to PID == 0.

Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-29 14:02:21 +01:00
Jacob Pan bb8313b603 cpuidle: Allow enforcing deepest idle state selection
When idle injection is used to cap power, we need to override the
governor's choice of idle states.

For this reason, make it possible the deepest idle state selection to
be enforced by setting a flag on a given CPU to achieve the maximum
potential power draw reduction.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-29 14:02:21 +01:00
Daniel Borkmann a3af5f8001 bpf: allow for mount options to specify permissions
Since we recently converted the BPF filesystem over to use mount_nodev(),
we now have the possibility to also hold mount options in sb's s_fs_info.
This work implements mount options support for specifying permissions on
the sb's inode, which will be used by tc when it manually needs to mount
the fs.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-27 20:38:47 -05:00
Daniel Borkmann 21116b7068 bpf: add owner_prog_type and accounted mem to array map's fdinfo
Allow for checking the owner_prog_type of a program array map. In some
cases bpf(2) can return -EINVAL /after/ the verifier passed and did all
the rewrites of the bpf program.

The reason that lets us fail at this late stage is that program array
maps are incompatible. Allow users to inspect this earlier after they
got the map fd through BPF_OBJ_GET command. tc will get support for this.

Also, display how much we charged the map with regards to RLIMIT_MEMLOCK.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-27 20:38:47 -05:00
Daniel Borkmann 88575199cc bpf: drop unnecessary context cast from BPF_PROG_RUN
Since long already bpf_func is not only about struct sk_buff * as
input anymore. Make it generic as void *, so that callers don't
need to cast for it each time they call BPF_PROG_RUN().

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-27 20:38:47 -05:00
AKASHI Takahiro 39290b389e module: extend 'rodata=off' boot cmdline parameter to module mappings
The current "rodata=off" parameter disables read-only kernel mappings
under CONFIG_DEBUG_RODATA:
    commit d2aa1acad2 ("mm/init: Add 'rodata=off' boot cmdline parameter
    to disable read-only kernel mappings")

This patch is a logical extension to module mappings ie. read-only mappings
at module loading can be disabled even if CONFIG_DEBUG_SET_MODULE_RONX
(mainly for debug use). Please note, however, that it only affects RO/RW
permissions, keeping NX set.

This is the first step to make CONFIG_DEBUG_SET_MODULE_RONX mandatory
(always-on) in the future as CONFIG_DEBUG_RODATA on x86 and arm64.

Suggested-by: and Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Link: http://lkml.kernel.org/r/20161114061505.15238-1-takahiro.akashi@linaro.org
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2016-11-27 16:15:33 -08:00
David S. Miller 0b42f25d2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
udplite conflict is resolved by taking what 'net-next' did
which removed the backlog receive method assignment, since
it is no longer necessary.

Two entries were added to the non-priv ethtool operations
switch statement, one in 'net' and one in 'net-next, so
simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-26 23:42:21 -05:00
Miroslav Benes 71d9f50793 module: Fix a comment above strong_try_module_get()
The comment above strong_try_module_get() function is not true anymore.
Return values changed with commit c9a3ba55bb ("module: wait for
dependent modules doing init.").

Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1611161635330.12580@pobox.suse.cz
[jeyu@redhat.com: style fixes to make checkpatch.pl happy]
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2016-11-26 11:18:03 -08:00
Aaron Tomlin 905dd707fc module: When modifying a module's text ignore modules which are going away too
By default, during the access permission modification of a module's core
and init pages, we only ignore modules that are malformed. Albeit for a
module which is going away, it does not make sense to change its text to
RO since the module should be RW, before deallocation.

This patch makes set_all_modules_text_ro() skip modules which are going
away too.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Link: http://lkml.kernel.org/r/1477560966-781-1-git-send-email-atomlin@redhat.com
[jeyu@redhat.com: add comment as suggested by Steven Rostedt]
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2016-11-26 11:18:03 -08:00
Aaron Tomlin 885a78d4a5 module: Ensure a module's state is set accordingly during module coming cleanup code
In load_module() in the event of an error, for e.g. unknown module
parameter(s) specified we go to perform some module coming clean up
operations. At this point the module is still in a "formed" state
when it is actually going away.

This patch updates the module's state accordingly to ensure anyone on the
module_notify_list waiting for a module going away notification will be
notified accordingly.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: http://lkml.kernel.org/r/1476980293-19062-2-git-send-email-atomlin@redhat.com
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2016-11-26 11:18:02 -08:00
Petr Mladek 7fd8329ba5 taint/module: Clean up global and module taint flags handling
The commit 66cc69e34e ("Fix: module signature vs tracepoints:
add new TAINT_UNSIGNED_MODULE") updated module_taint_flags() to
potentially print one more character. But it did not increase the
size of the corresponding buffers in m_show() and print_modules().

We have recently done the same mistake when adding a taint flag
for livepatching, see
https://lkml.kernel.org/r/cfba2c823bb984690b73572aaae1db596b54a082.1472137475.git.jpoimboe@redhat.com

Also struct module uses an incompatible type for mod-taints flags.
It survived from the commit 2bc2d61a96 ("[PATCH] list module
taint flags in Oops/panic"). There was used "int" for the global taint
flags at these times. But only the global tain flags was later changed
to "unsigned long" by the commit 25ddbb18aa ("Make the taint
flags reliable").

This patch defines TAINT_FLAGS_COUNT that can be used to create
arrays and buffers of the right size. Note that we could not use
enum because the taint flag indexes are used also in assembly code.

Then it reworks the table that describes the taint flags. The TAINT_*
numbers can be used as the index. Instead, we add information
if the taint flag is also shown per-module.

Finally, it uses "unsigned long", bit operations, and the updated
taint_flags table also for mod->taints.

It is not optimal because only few taint flags can be printed by
module_taint_flags(). But better be on the safe side. IMHO, it is
not worth the optimization and this is a good compromise.

Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: http://lkml.kernel.org/r/1474458442-21581-1-git-send-email-pmladek@suse.com
[jeyu@redhat.com: fix broken lkml link in changelog]
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2016-11-26 11:18:01 -08:00
Daniel Mack f432455148 bpf: add BPF_PROG_ATTACH and BPF_PROG_DETACH commands
Extend the bpf(2) syscall by two new commands, BPF_PROG_ATTACH and
BPF_PROG_DETACH which allow attaching and detaching eBPF programs
to a target.

On the API level, the target could be anything that has an fd in
userspace, hence the name of the field in union bpf_attr is called
'target_fd'.

When called with BPF_ATTACH_TYPE_CGROUP_INET_{E,IN}GRESS, the target is
expected to be a valid file descriptor of a cgroup v2 directory which
has the bpf controller enabled. These are the only use-cases
implemented by this patch at this point, but more can be added.

If a program of the given type already exists in the given cgroup,
the program is swapped automically, so userspace does not have to drop
an existing program first before installing a new one, which would
otherwise leave a gap in which no program is attached.

For more information on the propagation logic to subcgroups, please
refer to the bpf cgroup controller implementation.

The API is guarded by CAP_NET_ADMIN.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-25 16:26:04 -05:00
Daniel Mack 3007098494 cgroup: add support for eBPF programs
This patch adds two sets of eBPF program pointers to struct cgroup.
One for such that are directly pinned to a cgroup, and one for such
that are effective for it.

To illustrate the logic behind that, assume the following example
cgroup hierarchy.

  A - B - C
        \ D - E

If only B has a program attached, it will be effective for B, C, D
and E. If D then attaches a program itself, that will be effective for
both D and E, and the program in B will only affect B and C. Only one
program of a given type is effective for a cgroup.

Attaching and detaching programs will be done through the bpf(2)
syscall. For now, ingress and egress inet socket filtering are the
only supported use-cases.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-25 16:25:52 -05:00
Viresh Kumar d06e622d3d cpufreq: schedutil: Rectify comment in sugov_irq_work() function
This patch rectifies a comment present in sugov_irq_work() function to
follow proper grammar.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-24 21:50:59 +01:00
Tim Chen afe06efdf0 sched: Extend scheduler's asym packing
We generalize the scheduler's asym packing to provide an ordering
of the cpu beyond just the cpu number.  This allows the use of the
ASYM_PACKING scheduler machinery to move loads to preferred CPU in a
sched domain. The preference is defined with the cpu priority
given by arch_asym_cpu_priority(cpu).

We also record the most preferred cpu in a sched group when
we build the cpu's capacity for fast lookup of preferred cpu
during load balancing.

Co-developed-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-pm@vger.kernel.org
Cc: jolsa@redhat.com
Cc: rjw@rjwysocki.net
Cc: linux-acpi@vger.kernel.org
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: bp@suse.de
Link: http://lkml.kernel.org/r/0e73ae12737dfaafa46c07066cc7c5d3f1675e46.1479844244.git.tim.c.chen@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-24 14:09:46 +01:00
Mike Galbraith 83929cce95 sched/autogroup: Fix 64-bit kernel nice level adjustment
Michael Kerrisk reported:

> Regarding the previous paragraph...  My tests indicate
> that writing *any* value to the autogroup [nice priority level]
> file causes the task group to get a lower priority.

Because autogroup didn't call the then meaningless scale_load()...

Autogroup nice level adjustment has been broken ever since load
resolution was increased for 64-bit kernels.  Use scale_load() to
scale group weight.

Michael Kerrisk tested this patch to fix the problem:

> Applied and tested against 4.9-rc6 on an Intel u7 (4 cores).
> Test setup:
>
> Terminal window 1: running 40 CPU burner jobs
> Terminal window 2: running 40 CPU burner jobs
> Terminal window 1: running  1 CPU burner job
>
> Demonstrated that:
> * Writing "0" to the autogroup file for TW1 now causes no change
>   to the rate at which the process on the terminal consume CPU.
> * Writing -20 to the autogroup file for TW1 caused those processes
>   to get the lion's share of CPU while TW2 TW3 get a tiny amount.
> * Writing -20 to the autogroup files for TW1 and TW3 allowed the
>   process on TW3 to get as much CPU as it was getting as when
>   the autogroup nice values for both terminals were 0.

Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Tested-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-man <linux-man@vger.kernel.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1479897217.4306.6.camel@gmx.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-24 05:45:02 +01:00
Steven Rostedt (Red Hat) 38e11df134 ring-buffer: Force rb_end_commit() and rb_set_commit_to_write() inline
Both rb_end_commit() and rb_set_commit_to_write() are in the fast path of
the ring buffer recording. Make sure they are always inlined.

Link: http://lkml.kernel.org/r/20161121183700.GW26852@two.firstfloor.org

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-23 20:42:31 -05:00
Steven Rostedt (Red Hat) babe3fce95 ring-buffer: Froce rb_update_write_stamp() to be inlined
The function rb_update_write_stamp() is in the hotpath of the ring buffer
recording. Make sure that it is inlined as well. There's not many places
that call it.

Link: http://lkml.kernel.org/r/20161121183700.GW26852@two.firstfloor.org

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-23 20:38:39 -05:00
Steven Rostedt (Red Hat) 2289d5672f ring-buffer: Force inline of hotpath helper functions
There's several small helper functions in ring_buffer.c that are used in the
hot path. For some reason, even though they are marked inline, gcc tends not
to enforce it. Make sure these functions are always inlined.

Link: http://lkml.kernel.org/r/20161121183700.GW26852@two.firstfloor.org

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-23 20:35:32 -05:00
Steven Rostedt (Red Hat) 52ffabe384 tracing: Make __buffer_unlock_commit() always_inline
The function __buffer_unlock_commit() is called in a few places outside of
trace.c. But for the most part, it should really be inlined, as it is in the
hot path of the trace_events. For the callers outside of trace.c, create a
new function trace_buffer_unlock_commit_nostack(), as the reason it was used
was to avoid the stack tracing that trace_buffer_unlock_commit() could do.

Link: http://lkml.kernel.org/r/20161121183700.GW26852@two.firstfloor.org

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-23 20:30:51 -05:00
Steven Rostedt (Red Hat) 4239174570 tracing: Make tracepoint_printk a static_key
Currently, when tracepoint_printk is set (enabled by the "tp_printk" kernel
command line), it causes trace events to print via printk(). This is a very
dangerous operation, but is useful for debugging.

The issue is, it's seldom used, but it is always checked even if it's not
enabled by the kernel command line. Instead of having this feature called by
a branch against a variable, turn that variable into a static key, and this
will remove the test and jump.

To simplify things, the functions output_printk() and
trace_event_buffer_commit() were moved from trace_events.c to trace.c.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-23 15:52:45 -05:00
Steven Rostedt (Red Hat) 929ddbf3ef ring-buffer: Always inline rb_event_data()
The rb_event_data() is the fast path of getting the ring buffer data from an
event. Externally, ring_buffer_event_data() is used to access this function.
But unfortunately, rb_event_data() is not inlined, and calling
ring_buffer_event_data() causes that function to be called again. Force
rb_event_data() to be inlined to lower the number of operations needed when
calling ring_buffer_event_data().

Link: http://lkml.kernel.org/r/20161121183700.GW26852@two.firstfloor.org

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-23 11:40:34 -05:00
Steven Rostedt (Red Hat) fa7ffb39ef ring-buffer: Make rb_reserve_next_event() always inlined
The function rb_reserved_next_event() is called by two functions:
ring_buffer_lock_reserve() and ring_buffer_write(). This is in a very hot
path of the tracing code, and it is best that they are not functions. The
two callers are basically wrapers for rb_reserver_next_event(). Removing the
function calls can save execution time in the hotpath of tracing.

Link: http://lkml.kernel.org/r/20161121183700.GW26852@two.firstfloor.org

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-23 11:36:30 -05:00
Steven Rostedt (Red Hat) 3e9a8aadca tracing: Create a always_inlined __trace_buffer_lock_reserve()
As Andi Kleen pointed out in the Link below, the trace events has quite a
bit of code execution. A lot of that happens to be calling functions, where
some of them should simply be inlined. One of these functions happens to be
trace_buffer_lock_reserve() which is also a global, but it is used
throughout the file it is defined in. Create a __trace_buffer_lock_reserve()
that is always inlined that the file can benefit from.

Link: http://lkml.kernel.org/r/20161121183700.GW26852@two.firstfloor.org

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-23 11:29:58 -05:00
Linus Torvalds ded9b5dd20 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Six fixes for bugs that were found via fuzzing, and a trivial
  hw-enablement patch for AMD Family-17h CPU PMUs"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Allow only a single PMU/box within an events group
  perf/x86/intel: Cure bogus unwind from PEBS entries
  perf/x86: Restore TASK_SIZE check on frame pointer
  perf/core: Fix address filter parser
  perf/x86: Add perf support for AMD family-17h processors
  perf/x86/uncore: Fix crash by removing bogus event_list[] handling for SNB client uncore IMC
  perf/core: Do not set cpuctx->cgrp for unscheduled cgroups
2016-11-23 08:09:21 -08:00
Ingo Molnar 2b4d5b2582 sched/fair: Clean up the tunable parameter definitions
No change in functionality:

 - align the default values vertically to make them easier to scan
 - standardize the 'default:' lines
 - fix minor whitespace typos

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-23 10:38:55 +01:00
T.Zhou 176cedc4ed sched/dl: Fix comment in pick_next_task_dl()
Fix cut & paste oversight:

  s/pull_rt_task/pull_dl_task

Signed-off-by: T.Zhou <t1zhou@163.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: juri.lelli@gmail.com
Link: http://lkml.kernel.org/r/20161123004832.GA2983@geo
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-23 10:23:21 +01:00
Ingo Molnar ec84f00567 Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-23 10:23:09 +01:00
Ingo Molnar af91a81131 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

 - Documentation updates, yet again just simple changes.

 - Miscellaneous fixes, including a change to call_rcu()'s
   rcu_head alignment check.

 - Security-motivated list consistency checks, which are
   disabled by default behind DEBUG_LIST.

 - Torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-23 10:04:28 +01:00
Steven Rostedt (Red Hat) 7d43640022 tracing: Add error checks to creation of event files
The creation of the set_event_pid file was assigned to a variable "entry"
but that variable was never used. Ideally, it should be used to check if the
file was created and warn if it was not.

The files header_page, header_event should also be checked and a warning if
they fail to be created.

The "enable" file was moved up, as it is a more crucial file to have and a
hard failure (return -ENOMEM) should be returned if it is not created.

Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-22 18:32:03 -05:00
Chunyan Zhang 478409dd68 tracing: Add hook to function tracing for other subsystems to use
Currently Function traces can be only exported to the ring buffer. This
adds a trace_export concept which can process traces and export
them to a registered destination as an addition to the current
one that outputs to Ftrace - i.e. ring buffer.

In this way, if we want function traces to be sent to other destinations
rather than only to the ring buffer, we just need to register a new
trace_export and implement its own .write() function for writing traces to
storage.

With this patch, only function tracing (trace type is TRACE_FN)
is supported.

Link: http://lkml.kernel.org/r/1479715043-6534-2-git-send-email-zhang.chunyan@linaro.org

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-22 17:40:00 -05:00
Sebastian Andrzej Siewior 31eff2434d sched/nohz: Convert to hotplug state machine
Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: rt@linuxtronix.de
Link: http://lkml.kernel.org/r/20161117183541.8588-14-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-22 23:34:41 +01:00
Eric W. Biederman f84df2a6f2 exec: Ensure mm->user_ns contains the execed files
When the user namespace support was merged the need to prevent
ptrace from revealing the contents of an unreadable executable
was overlooked.

Correct this oversight by ensuring that the executed file
or files are in mm->user_ns, by adjusting mm->user_ns.

Use the new function privileged_wrt_inode_uidgid to see if
the executable is a member of the user namespace, and as such
if having CAP_SYS_PTRACE in the user namespace should allow
tracing the executable.  If not update mm->user_ns to
the parent user namespace until an appropriate parent is found.

Cc: stable@vger.kernel.org
Reported-by: Jann Horn <jann@thejh.net>
Fixes: 9e4a36ece6 ("userns: Fail exec for suid and sgid binaries with ids outside our user namespace.")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-11-22 13:21:00 -06:00
Eric W. Biederman 84d77d3f06 ptrace: Don't allow accessing an undumpable mm
It is the reasonable expectation that if an executable file is not
readable there will be no way for a user without special privileges to
read the file.  This is enforced in ptrace_attach but if ptrace
is already attached before exec there is no enforcement for read-only
executables.

As the only way to read such an mm is through access_process_vm
spin a variant called ptrace_access_vm that will fail if the
target process is not being ptraced by the current process, or
the current process did not have sufficient privileges when ptracing
began to read the target processes mm.

In the ptrace implementations replace access_process_vm by
ptrace_access_vm.  There remain several ptrace sites that still use
access_process_vm as they are reading the target executables
instructions (for kernel consumption) or register stacks.  As such it
does not appear necessary to add a permission check to those calls.

This bug has always existed in Linux.

Fixes: v1.0
Cc: stable@vger.kernel.org
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-11-22 12:57:38 -06:00
David S. Miller f9aa9dc7d2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
All conflicts were simple overlapping changes except perhaps
for the Thunder driver.

That driver has a change_mtu method explicitly for sending
a message to the hardware.  If that fails it returns an
error.

Normally a driver doesn't need an ndo_change_mtu method becuase those
are usually just range changes, which are now handled generically.
But since this extra operation is needed in the Thunder driver, it has
to stay.

However, if the message send fails we have to restore the original
MTU before the change because the entire call chain expects that if
an error is thrown by ndo_change_mtu then the MTU did not change.
Therefore code is added to nicvf_change_mtu to remember the original
MTU, and to restore it upon nicvf_update_hw_max_frs() failue.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-22 13:27:16 -05:00
Eric W. Biederman 64b875f7ac ptrace: Capture the ptracer's creds not PT_PTRACE_CAP
When the flag PT_PTRACE_CAP was added the PTRACE_TRACEME path was
overlooked.  This can result in incorrect behavior when an application
like strace traces an exec of a setuid executable.

Further PT_PTRACE_CAP does not have enough information for making good
security decisions as it does not report which user namespace the
capability is in.  This has already allowed one mistake through
insufficient granulariy.

I found this issue when I was testing another corner case of exec and
discovered that I could not get strace to set PT_PTRACE_CAP even when
running strace as root with a full set of caps.

This change fixes the above issue with strace allowing stracing as
root a setuid executable without disabling setuid.  More fundamentaly
this change allows what is allowable at all times, by using the correct
information in it's decision.

Cc: stable@vger.kernel.org
Fixes: 4214e42f96d4 ("v2.4.9.11 -> v2.4.9.12")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-11-22 11:49:49 -06:00
Eric W. Biederman bfedb58925 mm: Add a user_ns owner to mm_struct and fix ptrace permission checks
During exec dumpable is cleared if the file that is being executed is
not readable by the user executing the file.  A bug in
ptrace_may_access allows reading the file if the executable happens to
enter into a subordinate user namespace (aka clone(CLONE_NEWUSER),
unshare(CLONE_NEWUSER), or setns(fd, CLONE_NEWUSER).

This problem is fixed with only necessary userspace breakage by adding
a user namespace owner to mm_struct, captured at the time of exec, so
it is clear in which user namespace CAP_SYS_PTRACE must be present in
to be able to safely give read permission to the executable.

The function ptrace_may_access is modified to verify that the ptracer
has CAP_SYS_ADMIN in task->mm->user_ns instead of task->cred->user_ns.
This ensures that if the task changes it's cred into a subordinate
user namespace it does not become ptraceable.

The function ptrace_attach is modified to only set PT_PTRACE_CAP when
CAP_SYS_PTRACE is held over task->mm->user_ns.  The intent of
PT_PTRACE_CAP is to be a flag to note that whatever permission changes
the task might go through the tracer has sufficient permissions for
it not to be an issue.  task->cred->user_ns is always the same
as or descendent of mm->user_ns.  Which guarantees that having
CAP_SYS_PTRACE over mm->user_ns is the worst case for the tasks
credentials.

To prevent regressions mm->dumpable and mm->user_ns are not considered
when a task has no mm.  As simply failing ptrace_may_attach causes
regressions in privileged applications attempting to read things
such as /proc/<pid>/stat

Cc: stable@vger.kernel.org
Acked-by: Kees Cook <keescook@chromium.org>
Tested-by: Cyrill Gorcunov <gorcunov@openvz.org>
Fixes: 8409cca705 ("userns: allow ptrace from non-init user namespaces")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-11-22 11:49:48 -06:00
Pan Xinhui 05ffc95139 locking/mutex: Break out of expensive busy-loop on {mutex,rwsem}_spin_on_owner() when owner vCPU is preempted
An over-committed guest with more vCPUs than pCPUs has a heavy overload
in the two spin_on_owner. This blames on the lock holder preemption
issue.

Break out of the loop if the vCPU is preempted: if vcpu_is_preempted(cpu)
is true.

test-case:
perf record -a perf bench sched messaging -g 400 -p && perf report

before patch:
20.68%  sched-messaging  [kernel.vmlinux]  [k] mutex_spin_on_owner
 8.45%  sched-messaging  [kernel.vmlinux]  [k] mutex_unlock
 4.12%  sched-messaging  [kernel.vmlinux]  [k] system_call
 3.01%  sched-messaging  [kernel.vmlinux]  [k] system_call_common
 2.83%  sched-messaging  [kernel.vmlinux]  [k] copypage_power7
 2.64%  sched-messaging  [kernel.vmlinux]  [k] rwsem_spin_on_owner
 2.00%  sched-messaging  [kernel.vmlinux]  [k] osq_lock

after patch:
 9.99%  sched-messaging  [kernel.vmlinux]  [k] mutex_unlock
 5.28%  sched-messaging  [unknown]         [H] 0xc0000000000768e0
 4.27%  sched-messaging  [kernel.vmlinux]  [k] __copy_tofrom_user_power7
 3.77%  sched-messaging  [kernel.vmlinux]  [k] copypage_power7
 3.24%  sched-messaging  [kernel.vmlinux]  [k] _raw_write_lock_irq
 3.02%  sched-messaging  [kernel.vmlinux]  [k] system_call
 2.69%  sched-messaging  [kernel.vmlinux]  [k] wait_consider_task

Tested-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: boqun.feng@gmail.com
Cc: bsingharora@gmail.com
Cc: dave@stgolabs.net
Cc: kernellwp@gmail.com
Cc: konrad.wilk@oracle.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: mpe@ellerman.id.au
Cc: paulmck@linux.vnet.ibm.com
Cc: paulus@samba.org
Cc: rkrcmar@redhat.com
Cc: virtualization@lists.linux-foundation.org
Cc: will.deacon@arm.com
Cc: xen-devel-request@lists.xenproject.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1478077718-37424-4-git-send-email-xinhui.pan@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:48:10 +01:00
Pan Xinhui 5aff60a191 locking/osq: Break out of spin-wait busy waiting loop for a preempted vCPU in osq_lock()
An over-committed guest with more vCPUs than pCPUs has a heavy overload
in osq_lock().

This is because if vCPU-A holds the osq lock and yields out, vCPU-B ends
up waiting for per_cpu node->locked to be set. IOW, vCPU-B waits for
vCPU-A to run and unlock the osq lock.

Use the new vcpu_is_preempted(cpu) interface to detect if a vCPU is
currently running or not, and break out of the spin-loop if so.

test case:

 $ perf record -a perf bench sched messaging -g 400 -p && perf report

 before patch:
 18.09%  sched-messaging  [kernel.vmlinux]  [k] osq_lock
 12.28%  sched-messaging  [kernel.vmlinux]  [k] rwsem_spin_on_owner
  5.27%  sched-messaging  [kernel.vmlinux]  [k] mutex_unlock
  3.89%  sched-messaging  [kernel.vmlinux]  [k] wait_consider_task
  3.64%  sched-messaging  [kernel.vmlinux]  [k] _raw_write_lock_irq
  3.41%  sched-messaging  [kernel.vmlinux]  [k] mutex_spin_on_owner.is
  2.49%  sched-messaging  [kernel.vmlinux]  [k] system_call

 after patch:
 20.68%  sched-messaging  [kernel.vmlinux]  [k] mutex_spin_on_owner
  8.45%  sched-messaging  [kernel.vmlinux]  [k] mutex_unlock
  4.12%  sched-messaging  [kernel.vmlinux]  [k] system_call
  3.01%  sched-messaging  [kernel.vmlinux]  [k] system_call_common
  2.83%  sched-messaging  [kernel.vmlinux]  [k] copypage_power7
  2.64%  sched-messaging  [kernel.vmlinux]  [k] rwsem_spin_on_owner
  2.00%  sched-messaging  [kernel.vmlinux]  [k] osq_lock

Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Tested-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: bsingharora@gmail.com
Cc: dave@stgolabs.net
Cc: kernellwp@gmail.com
Cc: konrad.wilk@oracle.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: mpe@ellerman.id.au
Cc: paulmck@linux.vnet.ibm.com
Cc: paulus@samba.org
Cc: rkrcmar@redhat.com
Cc: virtualization@lists.linux-foundation.org
Cc: will.deacon@arm.com
Cc: xen-devel-request@lists.xenproject.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1478077718-37424-3-git-send-email-xinhui.pan@linux.vnet.ibm.com
[ Translated to English. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:48:10 +01:00
Ingo Molnar 02cb689b2c Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:37:38 +01:00
Oleg Nesterov 8e5bfa8c1f sched/autogroup: Do not use autogroup->tg in zombie threads
Exactly because for_each_thread() in autogroup_move_group() can't see it
and update its ->sched_task_group before _put() and possibly free().

So the exiting task needs another sched_move_task() before exit_notify()
and we need to re-introduce the PF_EXITING (or similar) check removed by
the previous change for another reason.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hartsjc@redhat.com
Cc: vbendel@redhat.com
Cc: vlovejoy@redhat.com
Link: http://lkml.kernel.org/r/20161114184612.GA15968@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:33:43 +01:00
Oleg Nesterov 18f649ef34 sched/autogroup: Fix autogroup_move_group() to never skip sched_move_task()
The PF_EXITING check in task_wants_autogroup() is no longer needed. Remove
it, but see the next patch.

However the comment is correct in that autogroup_move_group() must always
change task_group() for every thread so the sysctl_ check is very wrong;
we can race with cgroups and even sys_setsid() is not safe because a task
running with task_group() == ag->tg must participate in refcounting:

	int main(void)
	{
		int sctl = open("/proc/sys/kernel/sched_autogroup_enabled", O_WRONLY);

		assert(sctl > 0);
		if (fork()) {
			wait(NULL); // destroy the child's ag/tg
			pause();
		}

		assert(pwrite(sctl, "1\n", 2, 0) == 2);
		assert(setsid() > 0);
		if (fork())
			pause();

		kill(getppid(), SIGKILL);
		sleep(1);

		// The child has gone, the grandchild runs with kref == 1
		assert(pwrite(sctl, "0\n", 2, 0) == 2);
		assert(setsid() > 0);

		// runs with the freed ag/tg
		for (;;)
			sleep(1);

		return 0;
	}

crashes the kernel. It doesn't really need sleep(1), it doesn't matter if
autogroup_move_group() actually frees the task_group or this happens later.

Reported-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hartsjc@redhat.com
Cc: vbendel@redhat.com
Link: http://lkml.kernel.org/r/20161114184609.GA15965@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:33:42 +01:00
Marc Zyngier 4e20156640 genirq/msi: Drop artificial PCI dependency
The generic MSI layer doesn't have any PCI ties anymore, and the
build hack should have been removed some time ago.

Fixes: d9109698be ("genirq: Introduce msi_domain_alloc/free_irqs()")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1479806476-20801-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-22 11:00:19 +01:00
Linus Torvalds 8d1a2408ef Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller:

 1) With modern networking cards we can run out of 32-bit DMA space, so
    support 64-bit DMA addressing when possible on sparc64. From Dave
    Tushar.

 2) Some signal frame validation checks are inverted on sparc32, fix
    from Andreas Larsson.

 3) Lockdep tables can get too large in some circumstances on sparc64,
    add a way to adjust the size a bit. From Babu Moger.

 4) Fix NUMA node probing on some sun4v systems, from Thomas Tai.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: drop duplicate header scatterlist.h
  lockdep: Limit static allocations if PROVE_LOCKING_SMALL is defined
  config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc
  sunbmac: Fix compiler warning
  sunqe: Fix compiler warnings
  sparc64: Enable 64-bit DMA
  sparc64: Enable sun4v dma ops to use IOMMU v2 APIs
  sparc64: Bind PCIe devices to use IOMMU v2 service
  sparc64: Initialize iommu_map_table and iommu_pool
  sparc64: Add ATU (new IOMMU) support
  sparc64: Add FORCE_MAX_ZONEORDER and default to 13
  sparc64: fix compile warning section mismatch in find_node()
  sparc32: Fix inverted invalid_frame_pointer checks on sigreturns
  sparc64: Fix find_node warning if numa node cannot be found
2016-11-21 13:56:17 -08:00
Rafael J. Wysocki 08b98d3291 PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0 flag
Modify the ACPI system sleep support setup code to select
suspend-to-idle as the default system sleep state if the
ACPI_FADT_LOW_POWER_S0 flag is set in the FADT and the
default sleep state was not selected from the kernel command
line.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mario Limonciello <mario.limonciello@dell.com>
2016-11-21 22:48:10 +01:00
Rafael J. Wysocki 406e79385f PM / sleep: System sleep state selection interface rework
There are systems in which the platform doesn't support any special
sleep states, so suspend-to-idle (PM_SUSPEND_FREEZE) is the only
available system sleep state.  However, some user space frameworks
only use the "mem" and (sometimes) "standby" sleep state labels, so
the users of those systems need to modify user space in order to be
able to use system suspend at all and that may be a pain in practice.

Commit 0399d4db3e (PM / sleep: Introduce command line argument for
sleep state enumeration) attempted to address this problem by adding
a command line argument to change the meaning of the "mem" string in
/sys/power/state to make it trigger suspend-to-idle (instead of
suspend-to-RAM).

However, there also are systems in which the platform does support
special sleep states, but suspend-to-idle is the preferred one anyway
(it even may save more energy than the platform-provided sleep states
in some cases) and the above commit doesn't help in those cases.

For this reason, rework the system sleep state selection interface
again (but preserve backwards compatibiliby).  Namely, add a new
sysfs file, /sys/power/mem_sleep, that will control the system
suspend mode triggered by writing "mem" to /sys/power/state (in
analogy with what /sys/power/disk does for hibernation).  Make it
select suspend-to-RAM ("deep" sleep) by default (if supported) and
fall back to suspend-to-idle ("s2idle") otherwise and add a new
command line argument, mem_sleep_default, allowing that default to
be overridden if need be.

At the same time, drop the relative_sleep_states command line
argument that doesn't make sense any more.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mario Limonciello <mario.limonciello@dell.com>
2016-11-21 22:45:40 +01:00
Linus Torvalds 27e7ab99db Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Clear congestion control state when changing algorithms on an
    existing socket, from Florian Westphal.

 2) Fix register bit values in altr_tse_pcs portion of stmmac driver,
    from Jia Jie Ho.

 3) Fix PTP handling in stammc driver for GMAC4, from Giuseppe
    CAVALLARO.

 4) Fix udplite multicast delivery handling, it ignores the udp_table
    parameter passed into the lookups, from Pablo Neira Ayuso.

 5) Synchronize the space estimated by rtnl_vfinfo_size and the space
    actually used by rtnl_fill_vfinfo. From Sabrina Dubroca.

 6) Fix memory leak in fib_info when splitting nodes, from Alexander
    Duyck.

 7) If a driver does a napi_hash_del() explicitily and not via
    netif_napi_del(), it must perform RCU synchronization as needed. Fix
    this in virtio-net and bnxt drivers, from Eric Dumazet.

 8) Likewise, it is not necessary to invoke napi_hash_del() is we are
    also doing neif_napi_del() in the same code path. Remove such calls
    from be2net and cxgb4 drivers, also from Eric Dumazet.

 9) Don't allocate an ID in peernet2id_alloc() if the netns is dead,
    from WANG Cong.

10) Fix OF node and device struct leaks in of_mdio, from Johan Hovold.

11) We cannot cache routes in ip6_tunnel when using inherited traffic
    classes, from Paolo Abeni.

12) Fix several crashes and leaks in cpsw driver, from Johan Hovold.

13) Splice operations cannot use freezable blocking calls in AF_UNIX,
    from WANG Cong.

14) Link dump filtering by master device and kind support added an error
    in loop index updates during the dump if we actually do filter, fix
    from Zhang Shengju.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (59 commits)
  tcp: zero ca_priv area when switching cc algorithms
  net: l2tp: Treat NET_XMIT_CN as success in l2tp_eth_dev_xmit
  ethernet: stmmac: make DWMAC_STM32 depend on it's associated SoC
  tipc: eliminate obsolete socket locking policy description
  rtnl: fix the loop index update error in rtnl_dump_ifinfo()
  l2tp: fix racy SOCK_ZAPPED flag check in l2tp_ip{,6}_bind()
  net: macb: add check for dma mapping error in start_xmit()
  rtnetlink: fix FDB size computation
  netns: fix get_net_ns_by_fd(int pid) typo
  af_unix: conditionally use freezable blocking calls in read
  net: ethernet: ti: cpsw: fix fixed-link phy probe deferral
  net: ethernet: ti: cpsw: add missing sanity check
  net: ethernet: ti: cpsw: fix secondary-emac probe error path
  net: ethernet: ti: cpsw: fix of_node and phydev leaks
  net: ethernet: ti: cpsw: fix deferred probe
  net: ethernet: ti: cpsw: fix mdio device reference leak
  net: ethernet: ti: cpsw: fix bad register access in probe error path
  net: sky2: Fix shutdown crash
  cfg80211: limit scan results cache size
  net sched filters: pass netlink message flags in event notification
  ...
2016-11-21 13:26:28 -08:00
Daniel Borkmann 97bc402db7 bpf, mlx5: fix mlx5e_create_rq taking reference on prog
In mlx5e_create_rq(), when creating a new queue, we call bpf_prog_add() but
without checking the return value. bpf_prog_add() can fail since 92117d8443
("bpf: fix refcnt overflow"), so we really must check it. Take the reference
right when we assign it to the rq from priv->xdp_prog, and just drop the
reference on error path. Destruction in mlx5e_destroy_rq() looks good, though.

Fixes: 86994156c7 ("net/mlx5e: XDP fast RX drop bpf programs support")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-21 11:25:57 -05:00
Alexander Shishkin e96271f3ed perf/core: Fix address filter parser
The token table passed into match_token() must be null-terminated, which
it currently is not in the perf's address filter string parser, as caught
by Vince's perf_fuzzer and KASAN.

It doesn't blow up otherwise because of the alignment padding of the table
to the next element in the .rodata, which is luck.

Fixing by adding a null-terminator to the token table.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dvyukov@google.com
Cc: stable@vger.kernel.org # v4.7+
Fixes: 375637bc52 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/877f81f264.fsf@ashishki-desk.ger.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-21 11:28:36 +01:00
Waiman Long 194a6b5b9c sched/wake_q: Rename WAKE_Q to DEFINE_WAKE_Q
Currently the wake_q data structure is defined by the WAKE_Q() macro.
This macro, however, looks like a function doing something as "wake" is
a verb. Even checkpatch.pl was confused as it reported warnings like

  WARNING: Missing a blank line after declarations
  #548: FILE: kernel/futex.c:3665:
  +	int ret;
  +	WAKE_Q(wake_q);

This patch renames the WAKE_Q() macro to DEFINE_WAKE_Q() which clarifies
what the macro is doing and eliminates the checkpatch.pl warnings.

Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1479401198-1765-1-git-send-email-longman@redhat.com
[ Resolved conflict and added missing rename. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-21 10:29:01 +01:00
Steve Grubb c1e8f06d7a audit: fix formatting of AUDIT_CONFIG_CHANGE events
The AUDIT_CONFIG_CHANGE events sometimes use a op= field. The current
code logs the value of the field with quotes. This field is documented
to not be encoded, so it should not have quotes.

Signed-off-by: Steve Grubb <sgrubb@redhat.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
[PM: reformatted commit description to make checkpatch.pl happy]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-11-20 15:38:00 -05:00
Richard Guy Briggs 833fc48d18 audit: skip sessionid sentinel value when auto-incrementing
The value (unsigned int)-1 is used as a sentinel to indicate the
sessionID is unset.  Skip this value when the session_id value wraps.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-11-20 15:28:22 -05:00
Babu Moger e245d99e6c lockdep: Limit static allocations if PROVE_LOCKING_SMALL is defined
Reduce the size of data structure for lockdep entries by half if
PROVE_LOCKING_SMALL if defined. This is used only for sparc.

Signed-off-by: Babu Moger <babu.moger@oracle.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 11:33:19 -08:00
Alexey Dobriyan c7d03a00b5 netns: make struct pernet_operations::id unsigned int
Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

	void f(long *p, int i)
	{
		g(p[i]);
	}

  roughly translates to

	movsx	rsi, esi
	mov	rdi, [rsi+...]
	call 	g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

	static inline void *net_generic(const struct net *net, int id)
	{
		...
		ptr = ng->ptr[id - 1];
		...
	}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
	function                                     old     new   delta
	nfsd4_lock                                  3886    3959     +73
	tipc_link_build_proto_msg                   1096    1140     +44
	mac80211_hwsim_new_radio                    2776    2808     +32
	tipc_mon_rcv                                1032    1058     +26
	svcauth_gss_legacy_init                     1413    1429     +16
	tipc_bcbase_select_primary                   379     392     +13
	nfsd4_exchange_id                           1247    1260     +13
	nfsd4_setclientid_confirm                    782     793     +11
		...
	put_client_renew_locked                      494     480     -14
	ip_set_sockfn_get                            730     716     -14
	geneve_sock_add                              829     813     -16
	nfsd4_sequence_done                          721     703     -18
	nlmclnt_lookup_host                          708     686     -22
	nfsd4_lockt                                 1085    1063     -22
	nfs_get_client                              1077    1050     -27
	tcf_bpf_init                                1106    1076     -30
	nfsd4_encode_fattr                          5997    5930     -67
	Total: Before=154856051, After=154854321, chg -0.00%

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 10:59:15 -05:00
Thomas Gleixner f97960fbdd kernel/printk: Block cpuhotplug callback when tasks are frozen
The recent conversion of the console hotplug notifier to the state machine
missed the fact, that the notifier only operated on the non frozen
transitions. As a consequence the console_lock/unlock() pair is also
invoked during suspend, which results in a lockdep warning.

Restore the previous state by making the lock/unlock conditional on
!tasks_frozen.

Fixes: 90b14889d2 ("kernel/printk: Convert to hotplug state machine")
Reported-and-tested-by: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1611171729320.3645@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2016-11-17 19:44:58 +01:00
Ingo Molnar 89a01c51cb Merge branch 'x86/cpufeature' into x86/asm, to pick up dependency
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-17 08:30:54 +01:00
Viresh Kumar 21ef57297b cpufreq: schedutil: irq-work and mutex are only used in slow path
Execute the irq-work specific initialization/exit code only when the
fast path isn't available.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-16 23:21:08 +01:00
Viresh Kumar 02a7b1ee3b cpufreq: schedutil: move slow path from workqueue to SCHED_FIFO task
If slow path frequency changes are conducted in a SCHED_OTHER context
then they may be delayed for some amount of time, including
indefinitely, when real time or deadline activity is taking place.

Move the slow path to a real time kernel thread. In the future the
thread should be made SCHED_DEADLINE. The RT priority is arbitrarily set
to 50 for now.

Hackbench results on ARM Exynos, dual core A15 platform for 10
iterations:

$ hackbench -s 100 -l 100 -g 10 -f 20

Before			After
---------------------------------
1.808			1.603
1.847			1.251
2.229			1.590
1.952			1.600
1.947			1.257
1.925			1.627
2.694			1.620
1.258			1.621
1.919			1.632
1.250			1.240

Average:

1.8829			1.5041

Based on initial work by Steve Muckle.

Signed-off-by: Steve Muckle <smuckle.linux@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-16 23:21:08 +01:00
Viresh Kumar 4a71ce4348 cpufreq: schedutil: enable fast switch earlier
The fast_switch_enabled flag will be used by both sugov_policy_alloc()
and sugov_policy_free() with a later patch.

Prepare for that by moving the calls to enable and disable it to the
beginning of sugov_init() and end of sugov_exit().

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-16 23:21:08 +01:00
Viresh Kumar 8e2ddb0364 cpufreq: schedutil: Avoid indented labels
Switch to the more common practice of writing labels.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-16 23:21:07 +01:00
Josef Bacik f23cc643f9 bpf: fix range arithmetic for bpf map access
I made some invalid assumptions with BPF_AND and BPF_MOD that could result in
invalid accesses to bpf map entries.  Fix this up by doing a few things

1) Kill BPF_MOD support.  This doesn't actually get used by the compiler in real
life and just adds extra complexity.

2) Fix the logic for BPF_AND, don't allow AND of negative numbers and set the
minimum value to 0 for positive AND's.

3) Don't do operations on the ranges if they are set to the limits, as they are
by definition undefined, and allowing arithmetic operations on those values
could make them appear valid when they really aren't.

This fixes the testcase provided by Jann as well as a few other theoretical
problems.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16 13:21:45 -05:00
Thomas Gleixner b6e5d5b947 genirq/affinity: Use default affinity mask for reserved vectors
The reserved vectors at the beginning and the end of the vector space get
cpu_possible_mask assigned as their affinity mask.

All other non-auto affine interrupts get the default irq affinity mask
assigned. Using cpu_possible_mask breaks that rule.

Treat them like any other interrupt and use irq_default_affinity as target
mask.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
2016-11-16 18:44:01 +01:00
Christoph Hellwig bfe1307738 genirq/affinity: Take reserved vectors into account when spreading irqs
The recent addition of reserved vectors at the beginning or the end of the
vector space did not take the reserved vectors at the beginning into
account for the various loop exit conditions. As a consequence the last
vectors of the spread area are not included into the spread algorithm and
are treated like the reserved vectors at the end of the vector space and
get the default affinity mask assigned.

Sum up the affinity vectors and the reserved vectors at the beginning and
use the sum as exit condition.

[ tglx: Fixed all conditions instead of only one and massaged changelog ]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/1479201178-29604-2-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 18:44:01 +01:00
Martin KaFai Lau 2874aa2e46 bpf: Fix compilation warning in __bpf_lru_list_rotate_inactive
gcc-6.2.1 gives the following warning:
kernel/bpf/bpf_lru_list.c: In function ‘__bpf_lru_list_rotate_inactive.isra.3’:
kernel/bpf/bpf_lru_list.c:201:28: warning: ‘next’ may be used uninitialized in this function [-Wmaybe-uninitialized]

The "next" is currently initialized in the while() loop which must have >=1
iterations.

This patch initializes next to get rid of the compiler warning.

Fixes: 3a08c2fd76 ("bpf: LRU List")
Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16 11:30:56 -05:00
Vincent Guittot d03266910a sched/fair: Fix task group initialization
The moves of tasks are now propagated down to root and the utilization
of cfs_rq reflects reality so it doesn't need to be estimated at init.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: kernellwp@gmail.com
Cc: pjt@google.com
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1478598827-32372-7-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:11 +01:00
Vincent Guittot 4e5160766f sched/fair: Propagate asynchrous detach
A task can be asynchronously detached from cfs_rq when migrating
between CPUs. The load of the migrated task is then removed from
source cfs_rq during its next update. We use this event to set
propagation flag.

During the load balance, we take advantage of the update of blocked
load to propagate any pending changes.

The propagation relies on patch:

  "sched: Fix hierarchical order in rq->leaf_cfs_rq_list"

... which orders children and parents, to ensure that it's done in one pass.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: kernellwp@gmail.com
Cc: pjt@google.com
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1478598827-32372-6-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:10 +01:00
Vincent Guittot 09a43ace1f sched/fair: Propagate load during synchronous attach/detach
When a task moves from/to a cfs_rq, we set a flag which is then used to
propagate the change at parent level (sched_entity and cfs_rq) during
next update. If the cfs_rq is throttled, the flag will stay pending until
the cfs_rq is unthrottled.

For propagating the utilization, we copy the utilization of group cfs_rq to
the sched_entity.

For propagating the load, we have to take into account the load of the
whole task group in order to evaluate the load of the sched_entity.
Similarly to what was done before the rewrite of PELT, we add a correction
factor in case the task group's load is greater than its share so it will
contribute the same load of a task of equal weight.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: kernellwp@gmail.com
Cc: pjt@google.com
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1478598827-32372-5-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:10 +01:00
Vincent Guittot d31b1a66cb sched/fair: Factorize PELT update
Every time we modify load/utilization of sched_entity, we start to
sync it with its cfs_rq. This update is done in different ways:

 - when attaching/detaching a sched_entity, we update cfs_rq and then
   we sync the entity with the cfs_rq.

 - when enqueueing/dequeuing the sched_entity, we update both
   sched_entity and cfs_rq metrics to now.

Use update_load_avg() everytime we have to update and sync cfs_rq and
sched_entity before changing the state of a sched_enity.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: kernellwp@gmail.com
Cc: pjt@google.com
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1478598827-32372-4-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:09 +01:00
Vincent Guittot 9c2791f936 sched/fair: Fix hierarchical order in rq->leaf_cfs_rq_list
Fix the insertion of cfs_rq in rq->leaf_cfs_rq_list to ensure that a
child will always be called before its parent.

The hierarchical order in shares update list has been introduced by
commit:

  67e86250f8 ("sched: Introduce hierarchal order on shares update list")

With the current implementation a child can be still put after its
parent.

Lets take the example of:

       root
        \
         b
         /\
         c d*
           |
           e*

with root -> b -> c already enqueued but not d -> e so the
leaf_cfs_rq_list looks like: head -> c -> b -> root -> tail

The branch d -> e will be added the first time that they are enqueued,
starting with e then d.

When e is added, its parents is not already on the list so e is put at
the tail : head -> c -> b -> root -> e -> tail

Then, d is added at the head because its parent is already on the
list: head -> d -> c -> b -> root -> e -> tail

e is not placed at the right position and will be called the last
whereas it should be called at the beginning.

Because it follows the bottom-up enqueue sequence, we are sure that we
will finished to add either a cfs_rq without parent or a cfs_rq with a
parent that is already on the list. We can use this event to detect
when we have finished to add a new branch. For the others, whose
parents are not already added, we have to ensure that they will be
added after their children that have just been inserted the steps
before, and after any potential parents that are already in the list.
The easiest way is to put the cfs_rq just after the last inserted one
and to keep track of it untl the branch is fully added.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: kernellwp@gmail.com
Cc: pjt@google.com
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1478598827-32372-3-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:08 +01:00
Vincent Guittot df217913e7 sched/fair: Factorize attach/detach entity
Factorize post_init_entity_util_avg() and part of attach_task_cfs_rq()
in one function attach_entity_cfs_rq().

Create symmetric detach_entity_cfs_rq() function.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: kernellwp@gmail.com
Cc: pjt@google.com
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1478598827-32372-2-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:08 +01:00
Morten Rasmussen 893c5d2279 sched/fair: Fix incorrect comment for capacity_margin
The comment for capacity_margin introduced in:

  3273163c67 ("sched/fair: Let asymmetric CPU configurations balance at wake-up")

... got its usage the wrong way round - fix it.

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1476452472-24740-7-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:07 +01:00
Morten Rasmussen 9e0994c0a1 sched/fair: Avoid pulling tasks from non-overloaded higher capacity groups
For asymmetric CPU capacity systems it is counter-productive for
throughput if low capacity CPUs are pulling tasks from non-overloaded
CPUs with higher capacity. The assumption is that higher CPU capacity is
preferred over running alone in a group with lower CPU capacity.

This patch rejects higher CPU capacity groups with one or less task per
CPU as potential busiest group which could otherwise lead to a series of
failing load-balancing attempts leading to a force-migration.

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1476452472-24740-5-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:06 +01:00
Morten Rasmussen bf475ce0a3 sched/fair: Add per-CPU min capacity to sched_group_capacity
struct sched_group_capacity currently represents the compute capacity
sum of all CPUs in the sched_group.

Unless it is divided by the group_weight to get the average capacity
per CPU, it hides differences in CPU capacity for mixed capacity systems
(e.g. high RT/IRQ utilization or ARM big.LITTLE).

But even the average may not be sufficient if the group covers CPUs of
different capacities.

Instead, by extending struct sched_group_capacity to indicate min per-CPU
capacity in the group a suitable group for a given task utilization can
more easily be found such that CPUs with reduced capacity can be avoided
for tasks with high utilization (not implemented by this patch).

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1476452472-24740-4-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:06 +01:00
Morten Rasmussen 6a0b19c0f3 sched/fair: Consider spare capacity in find_idlest_group()
In low-utilization scenarios comparing relative loads in
find_idlest_group() doesn't always lead to the most optimum choice.
Systems with groups containing different numbers of cpus and/or cpus of
different compute capacity are significantly better off when considering
spare capacity rather than relative load in those scenarios.

In addition to existing load based search an alternative spare capacity
based candidate sched_group is found and selected instead if sufficient
spare capacity exists. If not, existing behaviour is preserved.

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1476452472-24740-3-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:05 +01:00
Morten Rasmussen 104cb16d9e sched/fair: Compute task/cpu utilization at wake-up correctly
At task wake-up load-tracking isn't updated until the task is enqueued.
The task's own view of its utilization contribution may therefore not be
aligned with its contribution to the cfs_rq load-tracking which may have
been updated in the meantime. Basically, the task's own utilization
hasn't yet accounted for the sleep decay, while the cfs_rq may have
(partially). Estimating the cfs_rq utilization in case the task is
migrated at wake-up as task_rq(p)->cfs.avg.util_avg - p->se.avg.util_avg
is therefore incorrect as the two load-tracking signals aren't time
synchronized (different last update).

To solve this problem, this patch synchronizes the task utilization with
its previous rq before the task utilization is used in the wake-up path.
Currently the update/synchronization is done _after_ the task has been
placed by select_task_rq_fair(). The synchronization is done without
having to take the rq lock using the existing mechanism used in
remove_entity_load_avg().

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1476452472-24740-2-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:05 +01:00
Martin Schwidefsky 527b0a76f4 sched/cpuacct: Avoid %lld seq_printf warning
For s390 kernel builds I keep getting this warning:

 kernel/sched/cpuacct.c: In function 'cpuacct_stats_show':
 kernel/sched/cpuacct.c:298:25: warning: format '%lld' expects argument of type 'long long int', but argument 4 has type 'clock_t {aka long int}' [-Wformat=]
   seq_printf(sf, "%s %lld\n",

Silence the warning by adding an explicit cast.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161111142749.6545-1-schwidefsky@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:29:03 +01:00
Ingo Molnar 0acbc7aa47 Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:16:28 +01:00
Christian Borntraeger f2f09a4cee locking/core: Remove cpu_relax_lowlatency() users
With the s390 special case of a yielding cpu_relax() implementation gone,
we can now remove all users of cpu_relax_lowlatency() and replace them
with cpu_relax().

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1477386195-32736-5-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:15:10 +01:00
Christian Borntraeger bf0d31c054 locking/core, stop_machine: Yield the CPU during stop machine()
Some time ago the following commit:

  57f2ffe14f ("s390: remove diag 44 calls from cpu_relax()")

... stopped cpu_relax() on s390 yielding to the hypervisor.

As it turns out this made stop_machine() run really slow on virtualized
overcommited systems. For example the kprobes test during bootup took
several seconds instead of just running unnoticed with large guests.

Therefore, yielding was reintroduced with commit:

  4d92f50249 ("s390: reintroduce diag 44 calls for cpu_relax()")

... but in fact the stop machine code seems to be the only place where
this yielding was really necessary. This place is probably the most
important one as it makes all but one guest CPUs wait for one guest CPU.

As we now have cpu_relax_yield(), we can use this in multi_cpu_stop().
For now lets only add it here. We can add it later in other places
when necessary.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1477386195-32736-3-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:15:09 +01:00
Nicolas Pitre baa73d9e47 posix-timers: Make them configurable
Some embedded systems have no use for them.  This removes about
25KB from the kernel binary size when configured out.

Corresponding syscalls are routed to a stub logging the attempt to
use those syscalls which should be enough of a clue if they were
disabled without proper consideration. They are: timer_create,
timer_gettime: timer_getoverrun, timer_settime, timer_delete,
clock_adjtime, setitimer, getitimer, alarm.

The clock_settime, clock_gettime, clock_getres and clock_nanosleep
syscalls are replaced by simple wrappers compatible with CLOCK_REALTIME,
CLOCK_MONOTONIC and CLOCK_BOOTTIME only which should cover the vast
majority of use cases with very little code.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-7-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:35 +01:00
Nicolas Pitre 53d3eaa315 posix_cpu_timers: Move the add_device_randomness() call to a proper place
There is no logical relation between add_device_randomness() and
posix_cpu_timers_exit(). Let's move the former to where the later
is called. This way, when posix-cpu-timers.c is compiled out, there
is no need to worry about not losing a call to add_device_randomness().

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-6-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:34 +01:00
Nicolas Pitre 74ba181e61 timer: Move sys_alarm from timer.c to itimer.c
Move the only user of alarm_setitimer to itimer.c where it is defined.
This allows for making alarm_setitimer static, and dropping it from the
build when __ARCH_WANT_SYS_ALARM is not defined.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-5-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:34 +01:00
Joel Fernandes d032ae8921 ftrace: Provide API to use global filtering for ftrace ops
Currently the global_ops filtering hash is not available to outside users
registering for function tracing. Provide an API for those users to be
able to choose global filtering.

This is in preparation for pstore's ftrace feature to be able to
use the global filters.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Joel Fernandes <joelaf@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:30 -08:00
Steven Rostedt fa32e8557b tracing: Add new trace_marker_raw
A new file is created:

 /sys/kernel/debug/tracing/trace_marker_raw

This allows for appications to create data structures and write the binary
data directly into it, and then read the trace data out from trace_pipe_raw
into the same type of data structure. This saves on converting numbers into
ASCII that would be required by trace_marker.

Suggested-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-15 15:13:59 -05:00
Martin KaFai Lau 8f8449384e bpf: Add BPF_MAP_TYPE_LRU_PERCPU_HASH
Provide a LRU version of the existing BPF_MAP_TYPE_PERCPU_HASH

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Martin KaFai Lau 29ba732acb bpf: Add BPF_MAP_TYPE_LRU_HASH
Provide a LRU version of the existing BPF_MAP_TYPE_HASH.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Martin KaFai Lau fd91de7b3c bpf: Refactor codes handling percpu map
Refactor the codes that populate the value
of a htab_elem in a BPF_MAP_TYPE_PERCPU_HASH
typed bpf_map.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Martin KaFai Lau 961578b634 bpf: Add percpu LRU list
Instead of having a common LRU list, this patch allows a
percpu LRU list which can be selected by specifying a map
attribute.  The map attribute will be added in the later
patch.

While the common use case for LRU is #reads >> #updates,
percpu LRU list allows bpf prog to absorb unusual #updates
under pathological case (e.g. external traffic facing machine which
could be under attack).

Each percpu LRU is isolated from each other.  The LRU nodes (including
free nodes) cannot be moved across different LRU Lists.

Here are the update performance comparison between
common LRU list and percpu LRU list (the test code is
at the last patch):

[root@kerneltest003.31.prn1 ~]# for i in 1 4 8; do echo -n "$i cpus: "; \
./map_perf_test 16 $i | awk '{r += $3}END{print r " updates"}'; done
 1 cpus: 2934082 updates
 4 cpus: 7391434 updates
 8 cpus: 6500576 updates

[root@kerneltest003.31.prn1 ~]# for i in 1 4 8; do echo -n "$i cpus: "; \
./map_perf_test 32 $i | awk '{r += $3}END{printr " updates"}'; done
  1 cpus: 2896553 updates
  4 cpus: 9766395 updates
  8 cpus: 17460553 updates

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Martin KaFai Lau 3a08c2fd76 bpf: LRU List
Introduce bpf_lru_list which will provide LRU capability to
the bpf_htab in the later patch.

* General Thoughts:
1. Target use case.  Read is more often than update.
   (i.e. bpf_lookup_elem() is more often than bpf_update_elem()).
   If bpf_prog does a bpf_lookup_elem() first and then an in-place
   update, it still counts as a read operation to the LRU list concern.
2. It may be useful to think of it as a LRU cache
3. Optimize the read case
   3.1 No lock in read case
   3.2 The LRU maintenance is only done during bpf_update_elem()
4. If there is a percpu LRU list, it will lose the system-wise LRU
   property.  A completely isolated percpu LRU list has the best
   performance but the memory utilization is not ideal considering
   the work load may be imbalance.
5. Hence, this patch starts the LRU implementation with a global LRU
   list with batched operations before accessing the global LRU list.
   As a LRU cache, #read >> #update/#insert operations, it will work well.
6. There is a local list (for each cpu) which is named
   'struct bpf_lru_locallist'.  This local list is not used to sort
   the LRU property.  Instead, the local list is to batch enough
   operations before acquiring the lock of the global LRU list.  More
   details on this later.
7. In the later patch, it allows a percpu LRU list by specifying a
   map-attribute for scalability reason and for use cases that need to
   prepare for the worst (and pathological) case like DoS attack.
   The percpu LRU list is completely isolated from each other and the
   LRU nodes (including free nodes) cannot be moved across the list.  The
   following description is for the global LRU list but mostly applicable
   to the percpu LRU list also.

* Global LRU List:
1. It has three sub-lists: active-list, inactive-list and free-list.
2. The two list idea, active and inactive, is borrowed from the
   page cache.
3. All nodes are pre-allocated and all sit at the free-list (of the
   global LRU list) at the beginning.  The pre-allocation reasoning
   is similar to the existing BPF_MAP_TYPE_HASH.  However,
   opting-out prealloc (BPF_F_NO_PREALLOC) is not supported in
   the LRU map.

* Active/Inactive List (of the global LRU list):
1. The active list, as its name says it, maintains the active set of
   the nodes.  We can think of it as the working set or more frequently
   accessed nodes.  The access frequency is approximated by a ref-bit.
   The ref-bit is set during the bpf_lookup_elem().
2. The inactive list, as its name also says it, maintains a less
   active set of nodes.  They are the candidates to be removed
   from the bpf_htab when we are running out of free nodes.
3. The ordering of these two lists is acting as a rough clock.
   The tail of the inactive list is the older nodes and
   should be released first if the bpf_htab needs free element.

* Rotating the Active/Inactive List (of the global LRU list):
1. It is the basic operation to maintain the LRU property of
   the global list.
2. The active list is only rotated when the inactive list is running
   low.  This idea is similar to the current page cache.
   Inactive running low is currently defined as
   "# of inactive < # of active".
3. The active list rotation always starts from the tail.  It moves
   node without ref-bit set to the head of the inactive list.
   It moves node with ref-bit set back to the head of the active
   list and then clears its ref-bit.
4. The inactive rotation is pretty simply.
   It walks the inactive list and moves the nodes back to the head of
   active list if its ref-bit is set. The ref-bit is cleared after moving
   to the active list.
   If the node does not have ref-bit set, it just leave it as it is
   because it is already in the inactive list.

* Shrinking the Inactive List (of the global LRU list):
1. Shrinking is the operation to get free nodes when the bpf_htab is
   full.
2. It usually only shrinks the inactive list to get free nodes.
3. During shrinking, it will walk the inactive list from the tail,
   delete the nodes without ref-bit set from bpf_htab.
4. If no free node found after step (3), it will forcefully get
   one node from the tail of inactive or active list.  Forcefully is
   in the sense that it ignores the ref-bit.

* Local List:
1. Each CPU has a 'struct bpf_lru_locallist'.  The purpose is to
   batch enough operations before acquiring the lock of the
   global LRU.
2. A local list has two sub-lists, free-list and pending-list.
3. During bpf_update_elem(), it will try to get from the free-list
   of (the current CPU local list).
4. If the local free-list is empty, it will acquire from the
   global LRU list.  The global LRU list can either satisfy it
   by its global free-list or by shrinking the global inactive
   list.  Since we have acquired the global LRU list lock,
   it will try to get at most LOCAL_FREE_TARGET elements
   to the local free list.
5. When a new element is added to the bpf_htab, it will
   first sit at the pending-list (of the local list) first.
   The pending-list will be flushed to the global LRU list
   when it needs to acquire free nodes from the global list
   next time.

* Lock Consideration:
The LRU list has a lock (lru_lock).  Each bucket of htab has a
lock (buck_lock).  If both locks need to be acquired together,
the lock order is always lru_lock -> buck_lock and this only
happens in the bpf_lru_list.c logic.

In hashtab.c, both locks are not acquired together (i.e. one
lock is always released first before acquiring another lock).

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Linus Torvalds 81bcfe5e48 Alexei discovered a race condition in modules failing to load that
can cause a ftrace check to trigger and disable ftrace. This is because
 of the way modules are registered to ftrace. Their functions are
 loaded in the ftrace function tables but set to "disabled" since
 they are still in the process of being loaded by the module. After
 the module is finished, it calls back into the ftrace infrastructure
 to enable it. Looking deeper into the locations that access all the
 functions in the table, I found more locations that should ignore
 the disabled ones.
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Merge tag 'trace-v4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Alexei discovered a race condition in modules failing to load that can
  cause a ftrace check to trigger and disable ftrace.

  This is because of the way modules are registered to ftrace. Their
  functions are loaded in the ftrace function tables but set to
  "disabled" since they are still in the process of being loaded by the
  module. After the module is finished, it calls back into the ftrace
  infrastructure to enable it.

  Looking deeper into the locations that access all the functions in the
  table, I found more locations that should ignore the disabled ones"

* tag 'trace-v4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Add more checks for FTRACE_FL_DISABLED in processing ip records
  ftrace: Ignore FTRACE_FL_DISABLED while walking dyn_ftrace records
2016-11-15 08:49:13 -08:00
David S. Miller bb598c1b8c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of bug fixes in 'net' overlapping other changes in
'net-next-.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 10:54:36 -05:00
David Carrillo-Cisneros 864c2357ca perf/core: Do not set cpuctx->cgrp for unscheduled cgroups
Commit:

  db4a835601 ("perf/core: Set cgroup in CPU contexts for new cgroup events")

failed to verify that event->cgrp is actually the scheduled cgroup
in a CPU before setting cpuctx->cgrp. This patch fixes that.

Now that there is a different path for scheduled and unscheduled
cgroup, add a warning to catch when cpuctx->cgrp is still set after
the last cgroup event has been unsheduled.

To verify the bug:

  # Create 2 cgroups.
  mkdir /dev/cgroups/devices/g1
  mkdir /dev/cgroups/devices/g2

  # launch a task, bind it to a cpu and move it to g1
  CPU=2
  while :; do : ; done &
  P=$!

  taskset -pc $CPU $P
  echo $P > /dev/cgroups/devices/g1/tasks

  # monitor g2 (it runs no tasks) and observe output
  perf stat -e cycles -I 1000 -C $CPU -G g2

  #           time             counts unit events
     1.000091408          7,579,527      cycles                    g2
     2.000350111      <not counted>      cycles                    g2
     3.000589181      <not counted>      cycles                    g2
     4.000771428      <not counted>      cycles                    g2

  # note first line that displays that a task run in g2, despite
  # g2 having no tasks. This is because cpuctx->cgrp was wrongly
  # set when context of new event was installed.
  # After applying the fix we obtain the right output:

  perf stat -e cycles -I 1000 -C $CPU -G g2
  #           time             counts unit events
     1.000119615      <not counted>      cycles                    g2
     2.000389430      <not counted>      cycles                    g2
     3.000590962      <not counted>      cycles                    g2

Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Link: http://lkml.kernel.org/r/1478026378-86083-1-git-send-email-davidcc@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-15 14:18:22 +01:00
Stanislaw Gruszka 353c50ebe3 sched/cputime: Simplify task_cputime()
Now since fetch_task_cputime() has no other users than task_cputime(),
its code could be used directly in task_cputime().

Moreover since only 2 task_cputime() calls of 17 use a NULL argument,
we can add dummy variables to those calls and remove NULL checks from
task_cputimes().

Also remove NULL checks from task_cputimes_scaled().

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1479175612-14718-5-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-15 09:51:05 +01:00
Stanislaw Gruszka 40565b5aed sched/cputime, powerpc, s390: Make scaled cputime arch specific
Only s390 and powerpc have hardware facilities allowing to measure
cputimes scaled by frequency. On all other architectures
utimescaled/stimescaled are equal to utime/stime (however they are
accounted separately).

Remove {u,s}timescaled accounting on all architectures except
powerpc and s390, where those values are explicitly accounted
in the proper places.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161031162143.GB12646@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-15 09:51:05 +01:00
Stanislaw Gruszka 981ee2d444 sched/cputime, powerpc: Remove cputime_to_scaled()
Currently cputime_to_scaled() just return it's argument on
all implementations, we don't need to call this function.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1479175612-14718-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-15 09:51:04 +01:00
Linus Torvalds e76d21c40b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix off by one wrt. indexing when dumping /proc/net/route entries,
    from Alexander Duyck.

 2) Fix lockdep splats in iwlwifi, from Johannes Berg.

 3) Cure panic when inserting certain netfilter rules when NFT_SET_HASH
    is disabled, from Liping Zhang.

 4) Memory leak when nft_expr_clone() fails, also from Liping Zhang.

 5) Disable UFO when path will apply IPSEC tranformations, from Jakub
    Sitnicki.

 6) Don't bogusly double cwnd in dctcp module, from Florian Westphal.

 7) skb_checksum_help() should never actually use the value "0" for the
    resulting checksum, that has a special meaning, use CSUM_MANGLED_0
    instead. From Eric Dumazet.

 8) Per-tx/rx queue statistic strings are wrong in qed driver, fix from
    Yuval MIntz.

 9) Fix SCTP reference counting of associations and transports in
    sctp_diag. From Xin Long.

10) When we hit ip6tunnel_xmit() we could have come from an ipv4 path in
    a previous layer or similar, so explicitly clear the ipv6 control
    block in the skb. From Eli Cooper.

11) Fix bogus sleeping inside of inet_wait_for_connect(), from WANG
    Cong.

12) Correct deivce ID of T6 adapter in cxgb4 driver, from Hariprasad
    Shenai.

13) Fix potential access past the end of the skb page frag array in
    tcp_sendmsg(). From Eric Dumazet.

14) 'skb' can legitimately be NULL in inet{,6}_exact_dif_match(). Fix
    from David Ahern.

15) Don't return an error in tcp_sendmsg() if we wronte any bytes
    successfully, from Eric Dumazet.

16) Extraneous unlocks in netlink_diag_dump(), we removed the locking
    but forgot to purge these unlock calls. From Eric Dumazet.

17) Fix memory leak in error path of __genl_register_family(). We leak
    the attrbuf, from WANG Cong.

18) cgroupstats netlink policy table is mis-sized, from WANG Cong.

19) Several XDP bug fixes in mlx5, from Saeed Mahameed.

20) Fix several device refcount leaks in network drivers, from Johan
    Hovold.

21) icmp6_send() should use skb dst device not skb->dev to determine L3
    routing domain. From David Ahern.

22) ip_vs_genl_family sets maxattr incorrectly, from WANG Cong.

23) We leak new macvlan port in some cases of maclan_common_netlink()
    errors. Fix from Gao Feng.

24) Similar to the icmp6_send() fix, icmp_route_lookup() should
    determine L3 routing domain using skb_dst(skb)->dev not skb->dev.
    Also from David Ahern.

25) Several fixes for route offloading and FIB notification handling in
    mlxsw driver, from Jiri Pirko.

26) Properly cap __skb_flow_dissect()'s return value, from Eric Dumazet.

27) Fix long standing regression in ipv4 redirect handling, wrt.
    validating the new neighbour's reachability. From Stephen Suryaputra
    Lin.

28) If sk_filter() trims the packet excessively, handle it reasonably in
    tcp input instead of exploding. From Eric Dumazet.

29) Fix handling of napi hash state when copying channels in sfc driver,
    from Bert Kenward.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (121 commits)
  mlxsw: spectrum_router: Flush FIB tables during fini
  net: stmmac: Fix lack of link transition for fixed PHYs
  sctp: change sk state only when it has assocs in sctp_shutdown
  bnx2: Wait for in-flight DMA to complete at probe stage
  Revert "bnx2: Reset device during driver initialization"
  ps3_gelic: fix spelling mistake in debug message
  net: ethernet: ixp4xx_eth: fix spelling mistake in debug message
  ibmvnic: Fix size of debugfs name buffer
  ibmvnic: Unmap ibmvnic_statistics structure
  sfc: clear napi_hash state when copying channels
  mlxsw: spectrum_router: Correctly dump neighbour activity
  mlxsw: spectrum: Fix refcount bug on span entries
  bnxt_en: Fix VF virtual link state.
  bnxt_en: Fix ring arithmetic in bnxt_setup_tc().
  Revert "include/uapi/linux/atm_zatm.h: include linux/time.h"
  tcp: take care of truncations done by sk_filter()
  ipv4: use new_gw for redirect neigh lookup
  r8152: Fix error path in open function
  net: bpqether.h: remove if_ether.h guard
  net: __skb_flow_dissect() must cap its return value
  ...
2016-11-14 14:15:53 -08:00
Zhou Chengming 8d414bd2f7 tracing: Allow wakeup_dl tracer to be used by instances
Allow wakeup_dl tracer to be used by instances, like wakeup tracer
and wakeup_rt tracer.

Link: http://lkml.kernel.org/r/1479093553-31264-1-git-send-email-zhouchengming1@huawei.com

Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-14 16:43:00 -05:00
Steven Rostedt (Red Hat) 3f303fbccf tracing/filter: Define op as the enum that it is
The trace_events_file.c filter logic can be a bit complex. I copy this into
a userspace program where I can debug it a bit easier. One issue is the op
is defined in most places as an int instead of as an enum, and gdb just
gives the value when debugging. Having the actual op name shown in gdb is
more useful.

This has no functionality change, but helps in debugging when the file is
debugged in user space.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-14 16:42:59 -05:00
Steven Rostedt (Red Hat) fdf5b67986 tracing: Optimise comparison filters and fix binary and for 64 bit
Currently the filter logic for comparisons (like greater-than and less-than)
are used, they share the same function and a switch statement is used to
jump to the comparison type to perform. This is done in the extreme hot path
of the tracing code, and it does not take much more space to create a
unique comparison function to perform each type of comparison and remove the
switch statement.

Also, a bug was found where the binary and operation for 64 bits could fail
if the resulting bits were greater than 32 bits, because the result was
passed into a 32 bit variable. This was fixed when adding the separate
binary and function.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-14 16:42:58 -05:00
Masami Hiramatsu 60f1d5e3ba ftrace: Support full glob matching
Use glob_match() to support flexible glob wildcards (*,?)
and character classes ([) for ftrace.
Since the full glob matching is slower than the current
partial matching routines(*pat, pat*, *pat*), this leaves
those routines and just add MATCH_GLOB for complex glob
expression.

e.g.
----
[root@localhost tracing]# echo 'sched*group' > set_ftrace_filter
[root@localhost tracing]# cat set_ftrace_filter
sched_free_group
sched_change_group
sched_create_group
sched_online_group
sched_destroy_group
sched_offline_group
[root@localhost tracing]# echo '[Ss]y[Ss]_*' > set_ftrace_filter
[root@localhost tracing]# head set_ftrace_filter
sys_arch_prctl
sys_rt_sigreturn
sys_ioperm
SyS_iopl
sys_modify_ldt
SyS_mmap
SyS_set_thread_area
SyS_get_thread_area
SyS_set_tid_address
sys_fork
----

Link: http://lkml.kernel.org/r/147566869501.29136.6462645009894738056.stgit@devbox

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-14 16:42:58 -05:00
Steven Rostedt (Red Hat) 546fece4ea ftrace: Add more checks for FTRACE_FL_DISABLED in processing ip records
When a module is first loaded and its function ip records are added to the
ftrace list of functions to modify, they are set to DISABLED, as their text
is still in a read only state. When the module is fully loaded, and can be
updated, the flag is cleared, and if their's any functions that should be
tracing them, it is updated at that moment.

But there's several locations that do record accounting and should ignore
records that are marked as disabled, or they can cause issues.

Alexei already fixed one location, but others need to be addressed.

Cc: stable@vger.kernel.org
Fixes: b7ffffbb46 "ftrace: Add infrastructure for delayed enabling of module functions"
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-14 16:31:49 -05:00
Alexei Starovoitov 977c1f9c8c ftrace: Ignore FTRACE_FL_DISABLED while walking dyn_ftrace records
ftrace_shutdown() checks for sanity of ftrace records
and if dyn_ftrace->flags is not zero, it will warn.
It can happen that 'flags' are set to FTRACE_FL_DISABLED at this point,
since some module was loaded, but before ftrace_module_enable()
cleared the flags for this module.

In other words the module.c is doing:
ftrace_module_init(mod); // calls ftrace_update_code() that sets flags=FTRACE_FL_DISABLED
... // here ftrace_shutdown() is called that warns, since
err = prepare_coming_module(mod); // didn't have a chance to clear FTRACE_FL_DISABLED

Fix it by ignoring disabled records.
It's similar to what __ftrace_hash_rec_update() is already doing.

Link: http://lkml.kernel.org/r/1478560460-3818619-1-git-send-email-ast@fb.com

Cc: stable@vger.kernel.org
Fixes: b7ffffbb46 "ftrace: Add infrastructure for delayed enabling of module functions"
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-14 16:31:41 -05:00
Mickaël Salaün 535e7b4b5e bpf: Use u64_to_user_ptr()
Replace the custom u64_to_ptr() function with the u64_to_user_ptr()
macro.

Signed-off-by: Mickaël Salaün <mic@digikod.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-14 16:23:08 -05:00
Richard Guy Briggs 8443075eac audit: tame initialization warning len_abuf in audit_log_execve_info
Tame initialization warning of len_abuf in audit_log_execve_info even
though there isn't presently a bug introduced by commit 43761473c2
("audit: fix a double fetch in audit_log_single_execve_arg()").  Using
UNINITIALIZED_VAR instead may mask future bugs.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-11-14 15:18:48 -05:00
Paul E. McKenney aa3e0bf1aa rcu: Don't kick unless grace period or request
The current code can result in spurious kicks when there are no grace
periods in progress and no grace-period-related requests.  This is
sort of OK for a diagnostic aid, but the resulting ftrace-dump messages
in dmesg are annoying.  This commit therefore avoids spurious kicks
in the common case.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2016-11-14 10:46:31 -08:00
Paul E. McKenney 0742ac3e2f rcu: Make expedited grace periods recheck dyntick idle state
Expedited grace periods check dyntick-idle state, and avoid sending
IPIs to idle CPUs, including those running guest OSes, and, on NOHZ_FULL
kernels, nohz_full CPUs.  However, the kernel has been observed checking
a CPU while it was non-idle, but sending the IPI after it has gone
idle.  This commit therefore rechecks idle state immediately before
sending the IPI, refraining from IPIing CPUs that have since gone idle.

Reported-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-11-14 10:46:31 -08:00
Paul E. McKenney d0af39e89e torture: Trace long read-side delays
Although rcutorture will occasionally do a 50-millisecond grace-period
delay, these delays are quite rare.  And rightly so, because otherwise
the read rate would be quite low.  Thie means that it can be important
to identify whether or not a given run contained a long-delay read.
This commit therefore inserts a trace_rcu_torture_read() event to flag
runs containing long delays.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-11-14 10:46:30 -08:00
Paul E. McKenney 1f21b50b77 rcu: Remove obsolete comment from __call_rcu()
The __call_rcu() comment about opportunistically noting grace period
beginnings and endings is obsolete.  RCU still does such opportunistic
noting, but in __call_rcu_core() rather than __call_rcu(), and there
already is an appropriate comment in __call_rcu_core().  This commit
therefore removes the obsolete comment.

Reported-by: Michalis Kokologiannakis <mixaskok@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2016-11-14 10:46:19 -08:00
Paul E. McKenney 5403d367a7 rcu: Remove obsolete rcu_check_callbacks() header comment
In the deep past, rcu_check_callbacks() was only invoked if rcu_pending()
returned true.  Which was fine, but these days rcu_check_callbacks()
is invoked unconditionally.  This commit therefore removes the obsolete
sentence from the header comment.

Reported-by: Michalis Kokologiannakis <mixaskok@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2016-11-14 10:46:14 -08:00
Paul E. McKenney b8f2ed5384 rcu: Tighten up __call_rcu() rcu_head alignment check
Commit 720abae3d6 ("rcu: force alignment on struct
callback_head/rcu_head") forced the rcu_head (AKA callback_head)
structure's alignment to pointer size, that is, to 4-byte boundaries on
32-bit systems and to 8-byte boundaries on 64-bit systems.  This
commit therefore checks for this same alignment in __call_rcu(),
which used to contain a looser check for two-byte alignment.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2016-11-14 10:46:08 -08:00
Linus Torvalds f5c9f9c723 Revert "printk: make reading the kernel log flush pending lines"
This reverts commit bfd8d3f23b.

It turns out that this flushes things much too aggressiverly, and causes
lines to break up when the system logger races with new continuation
lines being printed.

There's a pending patch to make printk() flushing much more
straightforward, but it's too invasive for 4.9, so in the meantime let's
just not make the system message logging flush continuation lines.
They'll be flushed by the final newline anyway.

Suggested-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-14 09:31:52 -08:00
Linus Torvalds 5d69561b7b Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fix from Ingo Molnar:
 "This fixes a genirq regression that resulted in the Intel/Broxton
  pinctrl/GPIO driver (and possibly others) spewing warnings"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Use irq type from irqdata instead of irqdesc
2016-11-14 08:34:56 -08:00
James Morris 185c0f26c0 Merge commit 'v4.9-rc5' into next 2016-11-14 09:34:01 +11:00
Daniel Borkmann c540594f86 bpf, mlx4: fix prog refcount in mlx4_en_try_alloc_resources error path
Commit 67f8b1dcb9 ("net/mlx4_en: Refactor the XDP forwarding rings
scheme") added a bug in that the prog's reference count is not dropped
in the error path when mlx4_en_try_alloc_resources() is failing from
mlx4_xdp_set().

We previously took bpf_prog_add(prog, priv->rx_ring_num - 1), that we
need to release again. Earlier in the call path, dev_change_xdp_fd()
itself holds a reference to the prog as well (hence the '- 1' in the
bpf_prog_add()), so a simple atomic_sub() is safe to use here. When
an error is propagated, then bpf_prog_put() is called eventually from
dev_change_xdp_fd()

Fixes: 67f8b1dcb9 ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-12 23:31:57 -05:00
Linus Torvalds b9f659b810 Power management fixes for v4.9-rc5
- Prevent the PM core from attempting to suspend parent devices
    if any of their children, whose suspend callbacks were invoked
    asynchronously, have failed to suspend during the "late" and
    "noirq" phases of system-wide suspend of devices (Brian Norris).
 
  - Prevent the boot-time system suspend test code from leaking a
    reference to the RTC device used by it (Johan Hovold).
 
  - Fix cpupower to use the return value of one of its library
    functions correctly and restore the correct behavior of it
    when used for setting cpufreq tunables broken during the 4.7
    development cycle (Laura Abbott).
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Merge tag 'pm-4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix two bugs in error code paths in the PM core (system-wide
  suspend of devices), a device reference leak in the boot-time suspend
  test code and a cpupower utility regression from the 4.7 cycle.

  Specifics:

   - Prevent the PM core from attempting to suspend parent devices if
     any of their children, whose suspend callbacks were invoked
     asynchronously, have failed to suspend during the "late" and
     "noirq" phases of system-wide suspend of devices (Brian Norris).

   - Prevent the boot-time system suspend test code from leaking a
     reference to the RTC device used by it (Johan Hovold).

   - Fix cpupower to use the return value of one of its library
     functions correctly and restore the correct behavior of it when
     used for setting cpufreq tunables broken during the 4.7 development
     cycle (Laura Abbott)"

* tag 'pm-4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / sleep: don't suspend parent when async child suspend_{noirq, late} fails
  PM / sleep: fix device reference leak in test_suspend
  cpupower: Correct return type of cpu_power_is_cpu_online() in cpufreq-set
2016-11-11 16:54:23 -08:00
Rafael J. Wysocki cd16f3dcdb Merge branches 'pm-tools-fixes' and 'pm-sleep-fixes'
* pm-tools-fixes:
  cpupower: Correct return type of cpu_power_is_cpu_online() in cpufreq-set

* pm-sleep-fixes:
  PM / sleep: don't suspend parent when async child suspend_{noirq, late} fails
  PM / sleep: fix device reference leak in test_suspend
2016-11-11 23:24:58 +01:00
Hans de Goede c6c7d83b9c Revert "console: don't prefer first registered if DT specifies stdout-path"
This reverts commit 05fd007e46 ("console: don't prefer first
registered if DT specifies stdout-path").

The reverted commit changes existing behavior on which many ARM boards
rely.  Many ARM small-board-computers, like e.g.  the Raspberry Pi have
both a video output and a serial console.  Depending on whether the user
is using the device as a more regular computer; or as a headless device
we need to have the console on either one or the other.

Many users rely on the kernel behavior of the console being present on
both outputs, before the reverted commit the console setup with no
console= kernel arguments on an ARM board which sets stdout-path in dt
would look like this:

  [root@localhost ~]# cat /proc/consoles
  ttyS0                -W- (EC p a)    4:64
  tty0                 -WU (E  p  )    4:1

Where as after the reverted commit, it looks like this:

  [root@localhost ~]# cat /proc/consoles
  ttyS0                -W- (EC p a)    4:64

This commit reverts commit 05fd007e46 ("console: don't prefer first
registered if DT specifies stdout-path") restoring the original
behavior.

Fixes: 05fd007e46 ("console: don't prefer first registered if DT specifies stdout-path")
Link: http://lkml.kernel.org/r/20161104121135.4780-2-hdegoede@redhat.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-11 08:12:37 -08:00
Daniel Bristot de Oliveira 9846d50df3 sched/deadline: Fix typo in a comment
In the comment:

        /*
         * The task might have changed its scheduling policy to something
         * different than SCHED_DEADLINE (through switched_fromd_dl()).
         */

s/fromd/from/

Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luca Abeni <luca.abeni@unitn.it>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/5408b3b3f9ee197a7b7f10fb834341100a4f2c88.1478599881.git.bristot@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-11 08:28:52 +01:00
Ingo Molnar bfdd5537dc Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-11 08:27:11 +01:00
Tahsin Erdogan 83f06168ef locking/lockdep: Remove unused parameter from the add_lock_to_list() function
The 'class' parameter is not used, remove it.
n
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1478592127-4376-1-git-send-email-tahsin@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-11 08:25:20 +01:00
Ingo Molnar 4c8ee71620 Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-11 08:25:07 +01:00
Tobias Klauser de464375da bpf: Remove unused but set variables
Remove the unused but set variables min_set and max_set in
adjust_reg_min_max_vals to fix the following warning when building with
'W=1':

  kernel/bpf/verifier.c:1483:7: warning: variable ‘min_set’ set but not used [-Wunused-but-set-variable]

There is no warning about max_set being unused, but since it is only
used in the assignment of min_set it can be removed as well.

They were introduced in commit 484611357c ("bpf: allow access into map
value arrays") but seem to have never been used.

Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-09 21:15:00 -05:00
Sebastian Andrzej Siewior 90b14889d2 kernel/printk: Convert to hotplug state machine
Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20161103145021.28528-3-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-09 23:45:26 +01:00
Christoph Hellwig 67c93c218d genirq/affinity: Handle pre/post vectors in irq_create_affinity_masks()
Only calculate the affinity for the main I/O vectors, and skip the
pre or post vectors specified by struct irq_affinity.

Also remove the irq_affinity cpumask argument that has never been used.
If we ever need it in the future we can pass it through struct
irq_affinity.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/1478654107-7384-4-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-09 08:25:09 +01:00
Christoph Hellwig 212bd84622 genirq/affinity: Handle pre/post vectors in irq_calc_affinity_vectors()
Only calculate the affinity for the main I/O vectors, and skip the pre or
post vectors specified by struct irq_affinity.

Also remove the irq_affinity cpumask argument that has never been used.  If
we ever need it in the future we can pass it through struct irq_affinity.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/1478654107-7384-3-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-09 08:25:08 +01:00
Thomas Gleixner 7ee7e87dfb genirq: Use irq type from irqdata instead of irqdesc
The type flags in the irq descriptor are there for historical reasons and
only updated via irq_modify_status() or irq_set_type(). Both functions also
update the type flags in irqdata. __setup_irq() is the only left over user
of the type flags in the irq descriptor.

If __setup_irq() is called with empty irq type flags, then the type flags
are retrieved from irqdata. If an interrupt is shared, then the type flags
are compared with the type flags stored in the irq descriptor. 

On x86 the ioapic does not have a irq_set_type() callback because the type
is defined in the BIOS tables and cannot be changed. The type is stored in
irqdata at setup time without updating the type data in the irq
descriptor. As a result the comparison described above fails.

There is no point in updating the irq descriptor flags because the only
relevant storage is irqdata. Use the type flags from irqdata for both
retrieval and comparison in __setup_irq() instead.

Aside of that the print out in case of non matching type flags has the old
and new type flags arguments flipped. Fix that as well.

For correctness sake the flags stored in the irq descriptor should be
removed, but this is beyond the scope of this bugfix and will be done in a
later patch.

Fixes: 4b357daed6 ("genirq: Look-up trigger type if not specified by caller")
Reported-and-tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jon Hunter <jonathanh@nvidia.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1611072020360.3501@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-08 15:15:19 +01:00
Daniel Borkmann 20b2b24f91 bpf: fix map not being uncharged during map creation failure
In map_create(), we first find and create the map, then once that
suceeded, we charge it to the user's RLIMIT_MEMLOCK, and then fetch
a new anon fd through anon_inode_getfd(). The problem is, once the
latter fails f.e. due to RLIMIT_NOFILE limit, then we only destruct
the map via map->ops->map_free(), but without uncharging the previously
locked memory first. That means that the user_struct allocation is
leaked as well as the accounted RLIMIT_MEMLOCK memory not released.
Make the label names in the fix consistent with bpf_prog_load().

Fixes: aaac3ba95e ("bpf: charge user for creation of BPF maps and programs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-07 13:22:26 -05:00
Daniel Borkmann 483bed2b0d bpf: fix htab map destruction when extra reserve is in use
Commit a6ed3ea65d ("bpf: restore behavior of bpf_map_update_elem")
added an extra per-cpu reserve to the hash table map to restore old
behaviour from pre prealloc times. When non-prealloc is in use for a
map, then problem is that once a hash table extra element has been
linked into the hash-table, and the hash table is destroyed due to
refcount dropping to zero, then htab_map_free() -> delete_all_elements()
will walk the whole hash table and drop all elements via htab_elem_free().
The problem is that the element from the extra reserve is first fed
to the wrong backend allocator and eventually freed twice.

Fixes: a6ed3ea65d ("bpf: restore behavior of bpf_map_update_elem")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-07 13:20:52 -05:00
Linus Torvalds ffbcbfca84 Merge branches 'sched-urgent-for-linus' and 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull stack vmap fixups from Thomas Gleixner:
 "Two small patches related to sched_show_task():

   - make sure to hold a reference on the task stack while accessing it

   - remove the thread_saved_pc printout

  .. and add a sanity check into release_task_stack() to catch problems
  with task stack references"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Remove pointless printout in sched_show_task()
  sched/core: Fix oops in sched_show_task()

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  fork: Add task stack refcounting sanity check and prevent premature task stack freeing
2016-11-05 11:46:02 -07:00
WANG Cong 243d521261 taskstats: fix the length of cgroupstats_cmd_get_policy
cgroupstats_cmd_get_policy is [CGROUPSTATS_CMD_ATTR_MAX+1],
taskstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1],
but their family.maxattr is TASKSTATS_CMD_ATTR_MAX.
CGROUPSTATS_CMD_ATTR_MAX is less than TASKSTATS_CMD_ATTR_MAX,
so we could end up accessing out-of-bound.

Change cgroupstats_cmd_get_policy to TASKSTATS_CMD_ATTR_MAX+1,
this is safe because the rest are initialized to 0's.

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-03 16:55:58 -04:00
Linus Torvalds 8243d55977 sched/core: Remove pointless printout in sched_show_task()
In sched_show_task() we print out a useless hex number, not even a
symbol, and there's a big question mark whether this even makes sense
anyway, I suspect we should just remove it all.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: brgerst@gmail.com
Cc: jann@thejh.net
Cc: keescook@chromium.org
Cc: linux-api@vger.kernel.org
Cc: tycho.andersen@canonical.com
Link: http://lkml.kernel.org/r/CA+55aFzphURPFzAvU4z6Moy7ZmimcwPuUdYU8bj9z0J+S8X1rw@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-03 07:31:34 +01:00
Tetsuo Handa 382005027f sched/core: Fix oops in sched_show_task()
When CONFIG_THREAD_INFO_IN_TASK=y, it is possible that an exited thread
remains in the task list after its stack pointer was already set to NULL.

Therefore, thread_saved_pc() and stack_not_used() in sched_show_task()
will trigger NULL pointer dereference if an attempt to dump such thread's
traces (e.g. SysRq-t, khungtaskd) is made.

Since show_stack() in sched_show_task() calls try_get_task_stack() and
sched_show_task() is called from interrupt context, calling
try_get_task_stack() from sched_show_task() will be safe as well.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: brgerst@gmail.com
Cc: jann@thejh.net
Cc: keescook@chromium.org
Cc: linux-api@vger.kernel.org
Cc: tycho.andersen@canonical.com
Link: http://lkml.kernel.org/r/201611021950.FEJ34368.HFFJOOMLtQOVSF@I-love.SAKURA.ne.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-03 07:27:34 +01:00
Johan Hovold ceb75787bc PM / sleep: fix device reference leak in test_suspend
Make sure to drop the reference taken by class_find_device() after
opening the RTC device.

Fixes: 77437fd4e6 (pm: boot time suspend selftest)
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-02 05:10:04 +01:00
Mickaël Salaün 285fdfc5d9 seccomp: Fix documentation
Fix struct seccomp_filter and seccomp_run_filters() signatures.

Signed-off-by: Mickaël Salaün <mic@digikod.net>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: James Morris <jmorris@namei.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Will Drewry <wad@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-01 08:54:26 -07:00
Christoph Hellwig 70fd76140a block,fs: use REQ_* flags directly
Remove the WRITE_* and READ_SYNC wrappers, and just use the flags
directly.  Where applicable this also drops usage of the
bio_set_op_attrs wrapper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-01 09:43:26 -06:00