Commit Graph

22264 Commits

Author SHA1 Message Date
Alexei Starovoitov
1e1dcd93b4 perf: split perf_trace_buf_prepare into alloc and update parts
split allows to move expensive update of 'struct trace_entry' to later phase.
Repurpose unused 1st argument of perf_tp_event() to indicate event type.

While splitting use temp variable 'rctx' instead of '*rctx' to avoid
unnecessary loads done by the compiler due to -fno-strict-aliasing

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07 21:04:26 -04:00
Alexei Starovoitov
ec5e099d6e perf: optimize perf_fetch_caller_regs
avoid memset in perf_fetch_caller_regs, since it's the critical path of all tracepoints.
It's called from perf_sw_event_sched, perf_event_task_sched_in and all of perf_trace_##call
with this_cpu_ptr(&__perf_regs[..]) which are zero initialized by perpcu init logic and
subsequent call to perf_arch_fetch_caller_regs initializes the same fields on all archs,
so we can safely drop memset from all of the above cases and move it into
perf_ftrace_function_call that calls it with stack allocated pt_regs.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07 21:04:26 -04:00
Linus Torvalds
4a2d057e4f Merge branch 'PAGE_CACHE_SIZE-removal'
Merge PAGE_CACHE_SIZE removal patches from Kirill Shutemov:
 "PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
  ago with promise that one day it will be possible to implement page
  cache with bigger chunks than PAGE_SIZE.

  This promise never materialized.  And unlikely will.

  Let's stop pretending that pages in page cache are special.  They are
  not.

  The first patch with most changes has been done with coccinelle.  The
  second is manual fixups on top.

  The third patch removes macros definition"

[ I was planning to apply this just before rc2, but then I spaced out,
  so here it is right _after_ rc2 instead.

  As Kirill suggested as a possibility, I could have decided to only
  merge the first two patches, and leave the old interfaces for
  compatibility, but I'd rather get it all done and any out-of-tree
  modules and patches can trivially do the converstion while still also
  working with older kernels, so there is little reason to try to
  maintain the redundant legacy model.    - Linus ]

* PAGE_CACHE_SIZE-removal:
  mm: drop PAGE_CACHE_* and page_cache_{get,release} definition
  mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage
  mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
2016-04-04 10:50:24 -07:00
Kirill A. Shutemov
09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Borislav Petkov
5c8a010c24 locking/lockdep: Fix print_collision() unused warning
Fix this:

  kernel/locking/lockdep.c:2051:13: warning: ‘print_collision’ defined but not used [-Wunused-function]
  static void print_collision(struct task_struct *curr,
              ^

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
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/1459759327-2880-1-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-04 11:41:34 +02:00
Linus Torvalds
4c3b73c6a2 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Misc kernel side fixes:

   - fix event leak
   - fix AMD PMU driver bug
   - fix core event handling bug
   - fix build bug on certain randconfigs

  Plus misc tooling fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/amd/ibs: Fix pmu::stop() nesting
  perf/core: Don't leak event in the syscall error path
  perf/core: Fix time tracking bug with multiplexing
  perf jit: genelf makes assumptions about endian
  perf hists: Fix determination of a callchain node's childlessness
  perf tools: Add missing initialization of perf_sample.cpumode in synthesized samples
  perf tools: Fix build break on powerpc
  perf/x86: Move events_sysfs_show() outside CPU_SUP_INTEL
  perf bench: Fix detached tarball building due to missing 'perf bench memcpy' headers
  perf tests: Fix tarpkg build test error output redirection
2016-04-03 07:22:12 -05:00
Linus Torvalds
7b367f5dba Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core kernel fixes from Ingo Molnar:
 "This contains the nohz/atomic cleanup/fix for the fetch_or() ugliness
  you noted during the original nohz pull request, plus there's also
  misc fixes:

   - fix liblockdep build bug
   - fix uapi header build bug
   - print more lockdep hash collision info to help debug recent reports
     of hash collisions
   - update MAINTAINERS email address"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  MAINTAINERS: Update my email address
  locking/lockdep: Print chain_key collision information
  uapi/linux/stddef.h: Provide __always_inline to userspace headers
  tools/lib/lockdep: Fix unsupported 'basename -s' in run_tests.sh
  locking/atomic, sched: Unexport fetch_or()
  timers/nohz: Convert tick dependency mask to atomic_t
  locking/atomic: Introduce atomic_fetch_or()
2016-04-03 07:06:53 -05:00
Linus Torvalds
05cf8077e5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Missing device reference in IPSEC input path results in crashes
    during device unregistration.  From Subash Abhinov Kasiviswanathan.

 2) Per-queue ISR register writes not being done properly in macb
    driver, from Cyrille Pitchen.

 3) Stats accounting bugs in bcmgenet, from Patri Gynther.

 4) Lightweight tunnel's TTL and TOS were swapped in netlink dumps, from
    Quentin Armitage.

 5) SXGBE driver has off-by-one in probe error paths, from Rasmus
    Villemoes.

 6) Fix race in save/swap/delete options in netfilter ipset, from
    Vishwanath Pai.

 7) Ageing time of bridge not set properly when not operating over a
    switchdev device.  Fix from Haishuang Yan.

 8) Fix GRO regression wrt nested FOU/GUE based tunnels, from Alexander
    Duyck.

 9) IPV6 UDP code bumps wrong stats, from Eric Dumazet.

10) FEC driver should only access registers that actually exist on the
    given chipset, fix from Fabio Estevam.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (73 commits)
  net: mvneta: fix changing MTU when using per-cpu processing
  stmmac: fix MDIO settings
  Revert "stmmac: Fix 'eth0: No PHY found' regression"
  stmmac: fix TX normal DESC
  net: mvneta: use cache_line_size() to get cacheline size
  net: mvpp2: use cache_line_size() to get cacheline size
  net: mvpp2: fix maybe-uninitialized warning
  tun, bpf: fix suspicious RCU usage in tun_{attach, detach}_filter
  net: usb: cdc_ncm: adding Telit LE910 V2 mobile broadband card
  rtnl: fix msg size calculation in if_nlmsg_size()
  fec: Do not access unexisting register in Coldfire
  net: mvneta: replace MVNETA_CPU_D_CACHE_LINE_SIZE with L1_CACHE_BYTES
  net: mvpp2: replace MVPP2_CPU_D_CACHE_LINE_SIZE with L1_CACHE_BYTES
  net: dsa: mv88e6xxx: Clear the PDOWN bit on setup
  net: dsa: mv88e6xxx: Introduce _mv88e6xxx_phy_page_{read, write}
  bpf: make padding in bpf_tunnel_key explicit
  ipv6: udp: fix UDP_MIB_IGNOREDMULTI updates
  bnxt_en: Fix ethtool -a reporting.
  bnxt_en: Fix typo in bnxt_hwrm_set_pause_common().
  bnxt_en: Implement proper firmware message padding.
  ...
2016-04-01 20:03:33 -05:00
Alfredo Alvarez Fernandez
39e2e173fb locking/lockdep: Print chain_key collision information
A sequence of pairs [class_idx -> corresponding chain_key iteration]
is printed for both the current held_lock chain and the cached chain.

That exposes the two different class_idx sequences that led to that
particular hash value.

This helps with debugging hash chain collision reports.

Signed-off-by: Alfredo Alvarez Fernandez <alfredoalvarezfernandez@gmail.com>
Acked-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: linux-fsdevel@vger.kernel.org
Cc: sedat.dilek@gmail.com
Cc: tytso@mit.edu
Link: http://lkml.kernel.org/r/1459357416-19190-1-git-send-email-alfredoalvarezernandez@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31 15:03:58 +02:00
Alexander Shishkin
201c2f85bd perf/core: Don't leak event in the syscall error path
In the error path, event_file not being NULL is used to determine
whether the event itself still needs to be free'd, so fix it up to
avoid leaking.

Reported-by: Leon Yu <chianglungyu@gmail.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 130056275a ("perf: Do not double free")
Link: http://lkml.kernel.org/r/87twk06yxp.fsf@ashishki-desk.ger.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31 09:54:07 +02:00
Peter Zijlstra
8fdc65391c perf/core: Fix time tracking bug with multiplexing
Stephane reported that commit:

  3cbaa59069 ("perf: Fix ctx time tracking by introducing EVENT_TIME")

introduced a regression wrt. time tracking, as easily observed by:

> This patch introduce a bug in the time tracking of events when
> multiplexing is used.
>
> The issue is easily reproducible with the following perf run:
>
>  $ perf stat -a -C 0 -e branches,branches,branches,branches,branches,branches -I 1000
>      1.000730239            652,394      branches   (66.41%)
>      1.000730239            597,809      branches   (66.41%)
>      1.000730239            593,870      branches   (66.63%)
>      1.000730239            651,440      branches   (67.03%)
>      1.000730239            656,725      branches   (66.96%)
>      1.000730239      <not counted>      branches
>
> One branches event is shown as not having run. Yet, with
> multiplexing, all events should run especially with a 1s (-I 1000)
> interval. The delta for time_running comes out to 0. Yet, the event
> has run because the kernel is actually multiplexing the events. The
> problem is that the time tracking is the kernel and especially in
> ctx_sched_out() is wrong now.
>
> The problem is that in case that the kernel enters ctx_sched_out() with the
> following state:
>    ctx->is_active=0x7 event_type=0x1
>    Call Trace:
>     [<ffffffff813ddd41>] dump_stack+0x63/0x82
>     [<ffffffff81182bdc>] ctx_sched_out+0x2bc/0x2d0
>     [<ffffffff81183896>] perf_mux_hrtimer_handler+0xf6/0x2c0
>     [<ffffffff811837a0>] ? __perf_install_in_context+0x130/0x130
>     [<ffffffff810f5818>] __hrtimer_run_queues+0xf8/0x2f0
>     [<ffffffff810f6097>] hrtimer_interrupt+0xb7/0x1d0
>     [<ffffffff810509a8>] local_apic_timer_interrupt+0x38/0x60
>     [<ffffffff8175ca9d>] smp_apic_timer_interrupt+0x3d/0x50
>     [<ffffffff8175ac7c>] apic_timer_interrupt+0x8c/0xa0
>
> In that case, the test:
>       if (is_active & EVENT_TIME)
>
> will be false and the time will not be updated. Time must always be updated on
> sched out.

Fix this by always updating time if EVENT_TIME was set, as opposed to
only updating time when EVENT_TIME changed.

Reported-by: Stephane Eranian <eranian@google.com>
Tested-by: Stephane Eranian <eranian@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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Cc: namhyung@kernel.org
Fixes: 3cbaa59069 ("perf: Fix ctx time tracking by introducing EVENT_TIME")
Link: http://lkml.kernel.org/r/20160329072644.GB3408@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31 09:54:06 +02:00
Frederic Weisbecker
5529578a27 locking/atomic, sched: Unexport fetch_or()
This patch functionally reverts:

  5fd7a09cfb ("atomic: Export fetch_or()")

During the merge Linus observed that the generic version of fetch_or()
was messy:

  " This makes the ugly "fetch_or()" macro that the scheduler used
    internally a new generic helper, and does a bad job at it. "

  e23604edac Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Now that we have introduced atomic_fetch_or(), fetch_or() is only used
by the scheduler in order to deal with thread_info flags which type
can vary across architectures.

Lets confine fetch_or() back to the scheduler so that we encourage
future users to use the more robust and well typed atomic_t version
instead.

While at it, fetch_or() gets robustified, pasting improvements from a
previous patch by Ingo Molnar that avoids needless expression
re-evaluations in the loop.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1458830281-4255-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-29 11:52:11 +02:00
Frederic Weisbecker
f009a7a767 timers/nohz: Convert tick dependency mask to atomic_t
The tick dependency mask was intially unsigned long because this is the
type on which clear_bit() operates on and fetch_or() accepts it.

But now that we have atomic_fetch_or(), we can instead use
atomic_andnot() to clear the bit. This consolidates the type of our
tick dependency mask, reduce its size on structures and benefit from
possible architecture optimizations on atomic_t operations.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1458830281-4255-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-29 11:52:11 +02:00
Alexander Potapenko
be7635e728 arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.

Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>.  Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.

Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25 16:37:42 -07:00
Michal Hocko
36324a990c oom: clear TIF_MEMDIE after oom_reaper managed to unmap the address space
When oom_reaper manages to unmap all the eligible vmas there shouldn't
be much of the freable memory held by the oom victim left anymore so it
makes sense to clear the TIF_MEMDIE flag for the victim and allow the
OOM killer to select another task.

The lack of TIF_MEMDIE also means that the victim cannot access memory
reserves anymore but that shouldn't be a problem because it would get
the access again if it needs to allocate and hits the OOM killer again
due to the fatal_signal_pending resp.  PF_EXITING check.  We can safely
hide the task from the OOM killer because it is clearly not a good
candidate anymore as everyhing reclaimable has been torn down already.

This patch will allow to cap the time an OOM victim can keep TIF_MEMDIE
and thus hold off further global OOM killer actions granted the oom
reaper is able to take mmap_sem for the associated mm struct.  This is
not guaranteed now but further steps should make sure that mmap_sem for
write should be blocked killable which will help to reduce such a lock
contention.  This is not done by this patch.

Note that exit_oom_victim might be called on a remote task from
__oom_reap_task now so we have to check and clear the flag atomically
otherwise we might race and underflow oom_victims or wake up waiters too
early.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25 16:37:42 -07:00
Andrew Morton
69b27baf00 sched: add schedule_timeout_idle()
This will be needed in the patch "mm, oom: introduce oom reaper".

Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25 16:37:42 -07:00
Daniel Borkmann
322cea2f41 bpf: add missing map_flags to bpf_map_show_fdinfo
Add map_flags attribute to bpf_map_show_fdinfo(), so that tools like
tc can check for them when loading objects from a pinned entry, e.g.
if user intent wrt allocation (BPF_F_NO_PREALLOC) is different to the
pinned object, it can bail out. Follow-up to 6c90598174 ("bpf:
pre-allocate hash map elements"), so that tc can still support this
with v4.6.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-25 11:36:41 -04:00
Linus Torvalds
3d66c6ba3f Power management and ACPI material for v4.6-rc1, part 2
- Fix for an intel_pstate driver issue related to the handling of
    MSR updates uncovered by the recent cpufreq rework (Rafael Wysocki).
 
  - cpufreq core cleanups related to starting governors and frequency
    synchronization during resume from system suspend and a locking
    fix for cpufreq_quick_get() (Rafael Wysocki, Richard Cochran).
 
  - acpi-cpufreq and powernv cpufreq driver updates (Jisheng Zhang,
    Michael Neuling, Richard Cochran, Shilpasri Bhat).
 
  - intel_idle driver update preventing some Skylake-H systems
    from hanging during initialization by disabling deep C-states
    mishandled by the platform in the problematic configurations (Len
    Brown).
 
  - Intel Xeon Phi Processor x200 support for intel_idle (Dasaratharaman
    Chandramouli).
 
  - cpuidle menu governor updates to make it always honor PM QoS
    latency constraints (and prevent C1 from being used as the
    fallback C-state on x86 when they are set below its exit latency)
    and to restore the previous behavior to fall back to C1 if the next
    timer event is set far enough in the future that was changed in 4.4
    which led to an energy consumption regression (Rik van Riel, Rafael
    Wysocki).
 
  - New device ID for a future AMD UART controller in the ACPI driver
    for AMD SoCs (Wang Hongcheng).
 
  - Rockchip rk3399 support for the rockchip-io-domain adaptive voltage
    scaling (AVS) driver (David Wu).
 
  - ACPI PCI resources management fix for the handling of IO space
    resources on architectures where the IO space is memory mapped
    (IA64 and ARM64) broken by the introduction of common ACPI
    resources parsing for PCI host bridges in 4.4 (Lorenzo Pieralisi).
 
  - Fix for the ACPI backend of the generic device properties API
    to make it parse non-device (data node only) children of an
    ACPI device correctly (Irina Tirdea).
 
  - Fixes for the handling of global suspend flags (introduced in 4.4)
    during hibernation and resume from it (Lukas Wunner).
 
  - Support for obtaining configuration information from Device Trees
    in the PM clocks framework (Jon Hunter).
 
  - ACPI _DSM helper code and devfreq framework cleanups (Colin Ian
    King, Geert Uytterhoeven).
 
 /
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Merge tag 'pm+acpi-4.6-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management and ACPI updates from Rafael Wysocki:
 "The second batch of power management and ACPI updates for v4.6.

  Included are fixups on top of the previous PM/ACPI pull request and
  other material that didn't make into it but still should go into 4.6.

  Among other things, there's a fix for an intel_pstate driver issue
  uncovered by recent cpufreq changes, a workaround for a boot hang on
  Skylake-H related to the handling of deep C-states by the platform and
  a PCI/ACPI fix for the handling of IO port resources on non-x86
  architectures plus some new device IDs and similar.

  Specifics:

   - Fix for an intel_pstate driver issue related to the handling of MSR
     updates uncovered by the recent cpufreq rework (Rafael Wysocki).

   - cpufreq core cleanups related to starting governors and frequency
     synchronization during resume from system suspend and a locking fix
     for cpufreq_quick_get() (Rafael Wysocki, Richard Cochran).

   - acpi-cpufreq and powernv cpufreq driver updates (Jisheng Zhang,
     Michael Neuling, Richard Cochran, Shilpasri Bhat).

   - intel_idle driver update preventing some Skylake-H systems from
     hanging during initialization by disabling deep C-states mishandled
     by the platform in the problematic configurations (Len Brown).

   - Intel Xeon Phi Processor x200 support for intel_idle
     (Dasaratharaman Chandramouli).

   - cpuidle menu governor updates to make it always honor PM QoS
     latency constraints (and prevent C1 from being used as the fallback
     C-state on x86 when they are set below its exit latency) and to
     restore the previous behavior to fall back to C1 if the next timer
     event is set far enough in the future that was changed in 4.4 which
     led to an energy consumption regression (Rik van Riel, Rafael
     Wysocki).

   - New device ID for a future AMD UART controller in the ACPI driver
     for AMD SoCs (Wang Hongcheng).

   - Rockchip rk3399 support for the rockchip-io-domain adaptive voltage
     scaling (AVS) driver (David Wu).

   - ACPI PCI resources management fix for the handling of IO space
     resources on architectures where the IO space is memory mapped
     (IA64 and ARM64) broken by the introduction of common ACPI
     resources parsing for PCI host bridges in 4.4 (Lorenzo Pieralisi).

   - Fix for the ACPI backend of the generic device properties API to
     make it parse non-device (data node only) children of an ACPI
     device correctly (Irina Tirdea).

   - Fixes for the handling of global suspend flags (introduced in 4.4)
     during hibernation and resume from it (Lukas Wunner).

   - Support for obtaining configuration information from Device Trees
     in the PM clocks framework (Jon Hunter).

   - ACPI _DSM helper code and devfreq framework cleanups (Colin Ian
     King, Geert Uytterhoeven)"

* tag 'pm+acpi-4.6-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (23 commits)
  PM / AVS: rockchip-io: add io selectors and supplies for rk3399
  intel_idle: Support for Intel Xeon Phi Processor x200 Product Family
  intel_idle: prevent SKL-H boot failure when C8+C9+C10 enabled
  ACPI / PM: Runtime resume devices when waking from hibernate
  PM / sleep: Clear pm_suspend_global_flags upon hibernate
  cpufreq: governor: Always schedule work on the CPU running update
  cpufreq: Always update current frequency before startig governor
  cpufreq: Introduce cpufreq_update_current_freq()
  cpufreq: Introduce cpufreq_start_governor()
  cpufreq: powernv: Add sysfs attributes to show throttle stats
  cpufreq: acpi-cpufreq: make Intel/AMD MSR access, io port access static
  PCI: ACPI: IA64: fix IO port generic range check
  ACPI / util: cast data to u64 before shifting to fix sign extension
  cpufreq: powernv: Define per_cpu chip pointer to optimize hot-path
  cpuidle: menu: Fall back to polling if next timer event is near
  cpufreq: acpi-cpufreq: Clean up hot plug notifier callback
  intel_pstate: Do not call wrmsrl_on_cpu() with disabled interrupts
  cpufreq: Make cpufreq_quick_get() safe to call
  ACPI / property: fix data node parsing in acpi_get_next_subnode()
  ACPI / APD: Add device HID for future AMD UART controller
  ...
2016-03-24 22:59:58 -07:00
Rafael J. Wysocki
3513ac743d Merge branches 'pm-avs', 'pm-clk', 'pm-devfreq' and 'pm-sleep'
* pm-avs:
  PM / AVS: rockchip-io: add io selectors and supplies for rk3399

* pm-clk:
  PM / clk: Add support for obtaining clocks from device-tree

* pm-devfreq:
  PM / devfreq: Spelling s/frequnecy/frequency/

* pm-sleep:
  ACPI / PM: Runtime resume devices when waking from hibernate
  PM / sleep: Clear pm_suspend_global_flags upon hibernate
2016-03-25 00:58:18 +01:00
Linus Torvalds
e46b4e2b46 Nothing major this round. Mostly small clean ups and fixes.
Some visible changes:
 
  A new flag was added to distinguish traces done in NMI context.
 
  Preempt tracer now shows functions where preemption is disabled but
  interrupts are still enabled.
 
 Other notes:
 
  Updates were done to function tracing to allow better performance
  with perf.
 
  Infrastructure code has been added to allow for a new histogram
  feature for recording live trace event histograms that can be
  configured by simple user commands. The feature itself was just
  finished, but needs a round in linux-next before being pulled.
  This only includes some infrastructure changes that will be needed.
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Merge tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "Nothing major this round.  Mostly small clean ups and fixes.

  Some visible changes:

   - A new flag was added to distinguish traces done in NMI context.

   - Preempt tracer now shows functions where preemption is disabled but
     interrupts are still enabled.

  Other notes:

   - Updates were done to function tracing to allow better performance
     with perf.

   - Infrastructure code has been added to allow for a new histogram
     feature for recording live trace event histograms that can be
     configured by simple user commands.  The feature itself was just
     finished, but needs a round in linux-next before being pulled.

     This only includes some infrastructure changes that will be needed"

* tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits)
  tracing: Record and show NMI state
  tracing: Fix trace_printk() to print when not using bprintk()
  tracing: Remove redundant reset per-CPU buff in irqsoff tracer
  x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c
  tracing: Fix crash from reading trace_pipe with sendfile
  tracing: Have preempt(irqs)off trace preempt disabled functions
  tracing: Fix return while holding a lock in register_tracer()
  ftrace: Use kasprintf() in ftrace_profile_tracefs()
  ftrace: Update dynamic ftrace calls only if necessary
  ftrace: Make ftrace_hash_rec_enable return update bool
  tracing: Fix typoes in code comment and printk in trace_nop.c
  tracing, writeback: Replace cgroup path to cgroup ino
  tracing: Use flags instead of bool in trigger structure
  tracing: Add an unreg_all() callback to trigger commands
  tracing: Add needs_rec flag to event triggers
  tracing: Add a per-event-trigger 'paused' field
  tracing: Add get_syscall_name()
  tracing: Add event record param to trigger_ops.func()
  tracing: Make event trigger functions available
  tracing: Make ftrace_event_field checking functions available
  ...
2016-03-24 10:52:25 -07:00
Linus Torvalds
3fa2fe2ce0 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "This tree contains various perf fixes on the kernel side, plus three
  hw/event-enablement late additions:

   - Intel Memory Bandwidth Monitoring events and handling
   - the AMD Accumulated Power Mechanism reporting facility
   - more IOMMU events

  ... and a final round of perf tooling updates/fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  perf llvm: Use strerror_r instead of the thread unsafe strerror one
  perf llvm: Use realpath to canonicalize paths
  perf tools: Unexport some methods unused outside strbuf.c
  perf probe: No need to use formatting strbuf method
  perf help: Use asprintf instead of adhoc equivalents
  perf tools: Remove unused perf_pathdup, xstrdup functions
  perf tools: Do not include stringify.h from the kernel sources
  tools include: Copy linux/stringify.h from the kernel
  tools lib traceevent: Remove redundant CPU output
  perf tools: Remove needless 'extern' from function prototypes
  perf tools: Simplify die() mechanism
  perf tools: Remove unused DIE_IF macro
  perf script: Remove lots of unused arguments
  perf thread: Rename perf_event__preprocess_sample_addr to thread__resolve
  perf machine: Rename perf_event__preprocess_sample to machine__resolve
  perf tools: Add cpumode to struct perf_sample
  perf tests: Forward the perf_sample in the dwarf unwind test
  perf tools: Remove misplaced __maybe_unused
  perf list: Fix documentation of :ppp
  perf bench numa: Fix assertion for nodes bitfield
  ...
2016-03-24 10:02:14 -07:00
Linus Torvalds
be53f58fa0 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Misc fixes: a cgroup fix, a fair-scheduler migration accounting fix, a
  cputime fix and two cpuacct cleanups"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/cpuacct: Simplify the cpuacct code
  sched/cpuacct: Rename parameter in cpuusage_write() for readability
  sched/fair: Add comments to explain select_idle_sibling()
  sched/fair: Fix fairness issue on migration
  sched/cgroup: Fix/cleanup cgroup teardown/init
  sched/cputime: Fix steal time accounting vs. CPU hotplug
2016-03-24 09:42:50 -07:00
Lukas Wunner
276142730c PM / sleep: Clear pm_suspend_global_flags upon hibernate
When suspending to RAM, waking up and later suspending to disk,
we gratuitously runtime resume devices after the thaw phase.
This does not occur if we always suspend to RAM or always to disk.

pm_complete_with_resume_check(), which gets called from
pci_pm_complete() among others, schedules a runtime resume
if PM_SUSPEND_FLAG_FW_RESUME is set. The flag is set during
a suspend-to-RAM cycle. It is cleared at the beginning of
the suspend-to-RAM cycle but not afterwards and it is not
cleared during a suspend-to-disk cycle at all. Fix it.

Fixes: ef25ba0476 (PM / sleep: Add flags to indicate platform firmware involvement)
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-23 02:43:11 +01:00
Joe Perches
a395d6a7e3 kernel/...: convert pr_warning to pr_warn
Use the more common logging method with the eventual goal of removing
pr_warning altogether.

Miscellanea:

 - Realign arguments
 - Coalesce formats
 - Add missing space between a few coalesced formats

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>	[kernel/power/suspend.c]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Brian Starkey
c907e0eb43 memremap: add MEMREMAP_WC flag
Add a flag to memremap() for writecombine mappings.  Mappings satisfied
by this flag will not be cached, however writes may be delayed or
combined into more efficient bursts.  This is most suitable for buffers
written sequentially by the CPU for use by other DMA devices.

Signed-off-by: Brian Starkey <brian.starkey@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Brian Starkey
cf61e2a148 memremap: don't modify flags
These patches implement a MEMREMAP_WC flag for memremap(), which can be
used to obtain writecombine mappings.  This is then used for setting up
dma_coherent_mem regions which use the DMA_MEMORY_MAP flag.

The motivation is to fix an alignment fault on arm64, and the suggestion
to implement MEMREMAP_WC for this case was made at [1].  That particular
issue is handled in patch 4, which makes sure that the appropriate
memset function is used when zeroing allocations mapped as IO memory.

This patch (of 4):

Don't modify the flags input argument to memremap(). MEMREMAP_WB is
already a special case so we can check for it directly instead of
clearing flag bits in each mapper.

Signed-off-by: Brian Starkey <brian.starkey@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Helge Deller
41b2715487 kernel/signal.c: add compile-time check for __ARCH_SI_PREAMBLE_SIZE
The value of __ARCH_SI_PREAMBLE_SIZE defines the size (including
padding) of the part of the struct siginfo that is before the union, and
it is then used to calculate the needed padding (SI_PAD_SIZE) to make
the size of struct siginfo equal to 128 (SI_MAX_SIZE) bytes.

Depending on the target architecture and word width it equals to either
3 or 4 times sizeof int.

Since the very beginning we had __ARCH_SI_PREAMBLE_SIZE wrong on the
parisc architecture for the 64bit kernel build.  It's even more
frustrating, because it can easily be checked at compile time if the
value was defined correctly.

This patch adds such a check for the correctness of
__ARCH_SI_PREAMBLE_SIZE in the hope that it will prevent existing and
future architectures from running into the same problem.

I refrained from replacing __ARCH_SI_PREAMBLE_SIZE by offsetof() in
copy_siginfo() in include/asm-generic/siginfo.h, because a) it doesn't
make any difference and b) it's used in the Documentation/kmemcheck.txt
example.

I ran this patch through the 0-DAY kernel test infrastructure and only
the parisc architecture triggered as expected.  That means that this
patch should be OK for all major architectures.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Dmitry Vyukov
5c9a8750a6 kernel: add kcov code coverage
kcov provides code coverage collection for coverage-guided fuzzing
(randomized testing).  Coverage-guided fuzzing is a testing technique
that uses coverage feedback to determine new interesting inputs to a
system.  A notable user-space example is AFL
(http://lcamtuf.coredump.cx/afl/).  However, this technique is not
widely used for kernel testing due to missing compiler and kernel
support.

kcov does not aim to collect as much coverage as possible.  It aims to
collect more or less stable coverage that is function of syscall inputs.
To achieve this goal it does not collect coverage in soft/hard
interrupts and instrumentation of some inherently non-deterministic or
non-interesting parts of kernel is disbled (e.g.  scheduler, locking).

Currently there is a single coverage collection mode (tracing), but the
API anticipates additional collection modes.  Initially I also
implemented a second mode which exposes coverage in a fixed-size hash
table of counters (what Quentin used in his original patch).  I've
dropped the second mode for simplicity.

This patch adds the necessary support on kernel side.  The complimentary
compiler support was added in gcc revision 231296.

We've used this support to build syzkaller system call fuzzer, which has
found 90 kernel bugs in just 2 months:

  https://github.com/google/syzkaller/wiki/Found-Bugs

We've also found 30+ bugs in our internal systems with syzkaller.
Another (yet unexplored) direction where kcov coverage would greatly
help is more traditional "blob mutation".  For example, mounting a
random blob as a filesystem, or receiving a random blob over wire.

Why not gcov.  Typical fuzzing loop looks as follows: (1) reset
coverage, (2) execute a bit of code, (3) collect coverage, repeat.  A
typical coverage can be just a dozen of basic blocks (e.g.  an invalid
input).  In such context gcov becomes prohibitively expensive as
reset/collect coverage steps depend on total number of basic
blocks/edges in program (in case of kernel it is about 2M).  Cost of
kcov depends only on number of executed basic blocks/edges.  On top of
that, kernel requires per-thread coverage because there are always
background threads and unrelated processes that also produce coverage.
With inlined gcov instrumentation per-thread coverage is not possible.

kcov exposes kernel PCs and control flow to user-space which is
insecure.  But debugfs should not be mapped as user accessible.

Based on a patch by Quentin Casasnovas.

[akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode']
[akpm@linux-foundation.org: unbreak allmodconfig]
[akpm@linux-foundation.org: follow x86 Makefile layout standards]
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Tavis Ormandy <taviso@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@google.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: David Drysdale <drysdale@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Arnd Bergmann
ade356b99a profile: hide unused functions when !CONFIG_PROC_FS
A couple of functions and variables in the profile implementation are
used only on SMP systems by the procfs code, but are unused if either
procfs is disabled or in uniprocessor kernels.  gcc prints a harmless
warning about the unused symbols:

  kernel/profile.c:243:13: error: 'profile_flip_buffers' defined but not used [-Werror=unused-function]
   static void profile_flip_buffers(void)
               ^
  kernel/profile.c:266:13: error: 'profile_discard_flip_buffers' defined but not used [-Werror=unused-function]
   static void profile_discard_flip_buffers(void)
               ^
  kernel/profile.c:330:12: error: 'profile_cpu_callback' defined but not used [-Werror=unused-function]
   static int profile_cpu_callback(struct notifier_block *info,
              ^

This adds further #ifdef to the file, to annotate exactly in which cases
they are used.  I have done several thousand ARM randconfig kernels with
this patch applied and no longer get any warnings in this file.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Hidehiro Kawai
ebc41f20d7 panic: change nmi_panic from macro to function
Commit 1717f2096b ("panic, x86: Fix re-entrance problem due to panic
on NMI") and commit 58c5661f21 ("panic, x86: Allow CPUs to save
registers even if looping in NMI context") introduced nmi_panic() which
prevents concurrent/recursive execution of panic().  It also saves
registers for the crash dump on x86.

However, there are some cases where NMI handlers still use panic().
This patch set partially replaces them with nmi_panic() in those cases.

Even this patchset is applied, some NMI or similar handlers (e.g.  MCE
handler) continue to use panic().  This is because I can't test them
well and actual problems won't happen.  For example, the possibility
that normal panic and panic on MCE happen simultaneously is very low.

This patch (of 3):

Convert nmi_panic() to a proper function and export it instead of
exporting internal implementation details to modules, for obvious
reasons.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com>
Cc: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Jann Horn
378c6520e7 fs/coredump: prevent fsuid=0 dumps into user-controlled directories
This commit fixes the following security hole affecting systems where
all of the following conditions are fulfilled:

 - The fs.suid_dumpable sysctl is set to 2.
 - The kernel.core_pattern sysctl's value starts with "/". (Systems
   where kernel.core_pattern starts with "|/" are not affected.)
 - Unprivileged user namespace creation is permitted. (This is
   true on Linux >=3.8, but some distributions disallow it by
   default using a distro patch.)

Under these conditions, if a program executes under secure exec rules,
causing it to run with the SUID_DUMP_ROOT flag, then unshares its user
namespace, changes its root directory and crashes, the coredump will be
written using fsuid=0 and a path derived from kernel.core_pattern - but
this path is interpreted relative to the root directory of the process,
allowing the attacker to control where a coredump will be written with
root privileges.

To fix the security issue, always interpret core_pattern for dumps that
are written under SUID_DUMP_ROOT relative to the root directory of init.

Signed-off-by: Jann Horn <jann@thejh.net>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Oleg Nesterov
1333ab0315 ptrace: change __ptrace_unlink() to clear ->ptrace under ->siglock
This test-case (simplified version of generated by syzkaller)

	#include <unistd.h>
	#include <sys/ptrace.h>
	#include <sys/wait.h>

	void test(void)
	{
		for (;;) {
			if (fork()) {
				wait(NULL);
				continue;
			}

			ptrace(PTRACE_SEIZE, getppid(), 0, 0);
			ptrace(PTRACE_INTERRUPT, getppid(), 0, 0);
			_exit(0);
		}
	}

	int main(void)
	{
		int np;

		for (np = 0; np < 8; ++np)
			if (!fork())
				test();

		while (wait(NULL) > 0)
			;
		return 0;
	}

triggers the 2nd WARN_ON_ONCE(!signr) warning in do_jobctl_trap().  The
problem is that __ptrace_unlink() clears task->jobctl under siglock but
task->ptrace is cleared without this lock held; this fools the "else"
branch which assumes that !PT_SEIZED means PT_PTRACED.

Note also that most of other PTRACE_SEIZE checks can race with detach
from the exiting tracer too.  Say, the callers of ptrace_trap_notify()
assume that SEIZED can't go away after it was checked.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Andy Lutomirski
efbc0fbf34 auditsc: for seccomp events, log syscall compat state using in_compat_syscall
Except on SPARC, this is what the code always did.  SPARC compat seccomp
was buggy, although the impact of the bug was limited because SPARC
32-bit and 64-bit syscall numbers are the same.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Andy Lutomirski
5c465217a9 ptrace: in PEEK_SIGINFO, check syscall bitness, not task bitness
Users of the 32-bit ptrace() ABI expect the full 32-bit ABI.  siginfo
translation should check ptrace() ABI, not caller task ABI.

This is an ABI change on SPARC.  Let's hope that no one relied on the
old buggy ABI.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Andy Lutomirski
5c38065e02 seccomp: check in_compat_syscall, not is_compat_task, in strict mode
Seccomp wants to know the syscall bitness, not the caller task bitness,
when it selects the syscall whitelist.

As far as I know, this makes no difference on any architecture, so it's
not a security problem.  (It generates identical code everywhere except
sparc, and, on sparc, the syscall numbering is the same for both ABIs.)

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Tetsuo Handa
b4aa14a63c kernel/hung_task.c: use timeout diff when timeout is updated
When new timeout is written to /proc/sys/kernel/hung_task_timeout_secs,
khungtaskd is interrupted and again sleeps for full timeout duration.

This means that hang task will not be checked if new timeout is written
periodically within old timeout duration and/or checking of hang task
will be delayed for up to previous timeout duration.  Fix this by
remembering last time khungtaskd checked hang task.

This change will allow other watchdog tasks (if any) to share khungtaskd
by sleeping for minimal timeout diff of all watchdog tasks.  Doing more
watchdog tasks from khungtaskd will reduce the possibility of printk()
collisions by multiple watchdog threads.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Peter Zijlstra
7e6867bf83 tracing: Record and show NMI state
The latency tracer format has a nice column to indicate IRQ state, but
this is not able to tell us about NMI state.

When tracing perf interrupt handlers (which often run in NMI context)
it is very useful to see how the events nest.

Link: http://lkml.kernel.org/r/20160318153022.105068893@infradead.org

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-22 18:04:10 -04:00
Steven Rostedt (Red Hat)
3debb0a9dd tracing: Fix trace_printk() to print when not using bprintk()
The trace_printk() code will allocate extra buffers if the compile detects
that a trace_printk() is used. To do this, the format of the trace_printk()
is saved to the __trace_printk_fmt section, and if that section is bigger
than zero, the buffers are allocated (along with a message that this has
happened).

If trace_printk() uses a format that is not a constant, and thus something
not guaranteed to be around when the print happens, the compiler optimizes
the fmt out, as it is not used, and the __trace_printk_fmt section is not
filled. This means the kernel will not allocate the special buffers needed
for the trace_printk() and the trace_printk() will not write anything to the
tracing buffer.

Adding a "__used" to the variable in the __trace_printk_fmt section will
keep it around, even though it is set to NULL. This will keep the string
from being printed in the debugfs/tracing/printk_formats section as it is
not needed.

Reported-by: Vlastimil Babka <vbabka@suse.cz>
Fixes: 07d777fe8c "tracing: Add percpu buffers for trace_printk()"
Cc: stable@vger.kernel.org # v3.5+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-22 18:02:40 -04:00
Linus Torvalds
5518f66b5a Merge branch 'for-4.6-ns' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup namespace support from Tejun Heo:
 "These are changes to implement namespace support for cgroup which has
  been pending for quite some time now.  It is very straight-forward and
  only affects what part of cgroup hierarchies are visible.

  After unsharing, mounting a cgroup fs will be scoped to the cgroups
  the task belonged to at the time of unsharing and the cgroup paths
  exposed to userland would be adjusted accordingly"

* 'for-4.6-ns' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix and restructure error handling in copy_cgroup_ns()
  cgroup: fix alloc_cgroup_ns() error handling in copy_cgroup_ns()
  Add FS_USERNS_FLAG to cgroup fs
  cgroup: Add documentation for cgroup namespaces
  cgroup: mount cgroupns-root when inside non-init cgroupns
  kernfs: define kernfs_node_dentry
  cgroup: cgroup namespace setns support
  cgroup: introduce cgroup namespaces
  sched: new clone flag CLONE_NEWCGROUP for cgroup namespace
  kernfs: Add API to generate relative kernfs path
2016-03-21 10:05:13 -07:00
Zhao Lei
73e6aafd9e sched/cpuacct: Simplify the cpuacct code
- Use for() instead of while() loop in some functions
   to make the code simpler.

 - Use this_cpu_ptr() instead of per_cpu_ptr() to make the code
   cleaner and a bit faster.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/d8a7ef9592f55224630cb26dea239f05b6398a4e.1458187654.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 11:00:28 +01:00
Dongsheng Yang
1a736b77a3 sched/cpuacct: Rename parameter in cpuusage_write() for readability
The name of the 'reset' parameter to cpuusage_write() is quite confusing,
because the only valid value we allow is '0', so !reset is actually the
case that resets ...

Rename it to 'val' and explain it in a comment that we only allow 0.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: cgroups@vger.kernel.org
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/1450696483-2864-1-git-send-email-yangds.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 10:59:29 +01:00
Matt Fleming
d4335581dc sched/fair: Add comments to explain select_idle_sibling()
It's not entirely obvious how the main loop in select_idle_sibling()
works on first glance. Sprinkle a few comments to explain the design
and intention behind the loop based on some conversations with Mike
and Peter.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.com>
Cc: Mike Galbraith <mgalbraith@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1457535548-15329-1-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 10:52:51 +01:00
Peter Zijlstra
3a47d5124a sched/fair: Fix fairness issue on migration
Pavan reported that in the presence of very light tasks (or cgroups)
the placement of migrated tasks can cause severe fairness issues.

The problem is that enqueue_entity() places the task before it updates
time, thereby it can place the task far in the past (remember that
light tasks will shoot virtual time forward at a high speed, so in
relation to the pre-existing light task, we can land far in the past).

This is done because update_curr() needs the current task, and we
might be placing the current task.

The obvious solution is to differentiate between the current and any
other task; placing the current before we update time, and placing any
other task after, such that !curr tasks end up at the current moment
in time, and not in the past.

Reported-by: Pavan Kondeti <pkondeti@codeaurora.org>
Tested-by: Pavan Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: byungchul.park@lge.com
Link: http://lkml.kernel.org/r/20160309120403.GK6344@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 10:49:23 +01:00
Peter Zijlstra
2f5177f0fd sched/cgroup: Fix/cleanup cgroup teardown/init
The CPU controller hasn't kept up with the various changes in the whole
cgroup initialization / destruction sequence, and commit:

  2e91fa7f6d ("cgroup: keep zombies associated with their original cgroups")

caused it to explode.

The reason for this is that zombies do not inhibit css_offline() from
being called, but do stall css_released(). Now we tear down the cfs_rq
structures on css_offline() but zombies can run after that, leading to
use-after-free issues.

The solution is to move the tear-down to css_released(), which
guarantees nobody (including no zombies) is still using our cgroup.

Furthermore, a few simple cleanups are possible too. There doesn't
appear to be any point to us using css_online() (anymore?) so fold that
in css_alloc().

And since cgroup code guarantees an RCU grace period between
css_released() and css_free() we can forgo using call_rcu() and free the
stuff immediately.

Suggested-by: Tejun Heo <tj@kernel.org>
Reported-by: Kazuki Yamaguchi <k@rhe.jp>
Reported-by: Niklas Cassel <niklas.cassel@axis.com>
Tested-by: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 2e91fa7f6d ("cgroup: keep zombies associated with their original cgroups")
Link: http://lkml.kernel.org/r/20160316152245.GY6344@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 10:49:23 +01:00
Ingo Molnar
42e405f7b1 Merge branch 'linus' into sched/urgent, to pick up dependencies
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 10:47:40 +01:00
Peter Zijlstra
1dcaac1ce0 perf/core: Document some hotplug bits
Document some of the hotplug notifier usage.

Requested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 09:35:29 +01:00
Peter Zijlstra
8184059e93 perf/core: Fix Undefined behaviour in rb_alloc()
Sasha reported:

 [ 3494.030114] UBSAN: Undefined behaviour in kernel/events/ring_buffer.c:685:22
 [ 3494.030647] shift exponent -1 is negative

Andrey spotted that this is because:

  It happens if nr_pages = 0:
     rb->page_order = ilog2(nr_pages);

Fix it by making both assignments conditional on nr_pages; since
otherwise they should both be 0 anyway, and will be because of the
kzalloc() used to allocate the structure.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Reported-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20160129141751.GA407@worktop
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 09:08:18 +01:00
Peter Zijlstra
91a612eea9 perf/core: Fix dynamic interrupt throttle
There were two problems with the dynamic interrupt throttle mechanism,
both triggered by the same action.

When you (or perf_fuzzer) write a huge value into
/proc/sys/kernel/perf_event_max_sample_rate the computed
perf_sample_allowed_ns becomes 0. This effectively disables the whole
dynamic throttle.

This is fixed by ensuring update_perf_cpu_limits() never sets the
value to 0. However, we allow disabling of the dynamic throttle by
writing 100 to /proc/sys/kernel/perf_cpu_time_max_percent. This will
generate a warning in dmesg.

The second problem is that by setting the max_sample_rate to a huge
number, the adaptive process can take a few tries, since it halfs the
limit each time. Change that to directly compute a new value based on
the observed duration.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 09:08:17 +01:00
Peter Zijlstra
1e02cd40f1 perf/core: Fix the unthrottle logic
Its possible to IOC_PERIOD while the event is throttled, this would
re-start the event and the next tick would then try to unthrottle it,
and find the event wasn't actually stopped anymore.

This would tickle a WARN in the x86-pmu code which isn't expecting to
start a !stopped event.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: dvyukov@google.com
Cc: oleg@redhat.com
Cc: panand@redhat.com
Cc: sasha.levin@oracle.com
Cc: vince@deater.net
Link: http://lkml.kernel.org/r/20160310143924.GR6356@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 09:08:14 +01:00
Linus Torvalds
643ad15d47 Merge branch 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 protection key support from Ingo Molnar:
 "This tree adds support for a new memory protection hardware feature
  that is available in upcoming Intel CPUs: 'protection keys' (pkeys).

  There's a background article at LWN.net:

      https://lwn.net/Articles/643797/

  The gist is that protection keys allow the encoding of
  user-controllable permission masks in the pte.  So instead of having a
  fixed protection mask in the pte (which needs a system call to change
  and works on a per page basis), the user can map a (handful of)
  protection mask variants and can change the masks runtime relatively
  cheaply, without having to change every single page in the affected
  virtual memory range.

  This allows the dynamic switching of the protection bits of large
  amounts of virtual memory, via user-space instructions.  It also
  allows more precise control of MMU permission bits: for example the
  executable bit is separate from the read bit (see more about that
  below).

  This tree adds the MM infrastructure and low level x86 glue needed for
  that, plus it adds a high level API to make use of protection keys -
  if a user-space application calls:

        mmap(..., PROT_EXEC);

  or

        mprotect(ptr, sz, PROT_EXEC);

  (note PROT_EXEC-only, without PROT_READ/WRITE), the kernel will notice
  this special case, and will set a special protection key on this
  memory range.  It also sets the appropriate bits in the Protection
  Keys User Rights (PKRU) register so that the memory becomes unreadable
  and unwritable.

  So using protection keys the kernel is able to implement 'true'
  PROT_EXEC on x86 CPUs: without protection keys PROT_EXEC implies
  PROT_READ as well.  Unreadable executable mappings have security
  advantages: they cannot be read via information leaks to figure out
  ASLR details, nor can they be scanned for ROP gadgets - and they
  cannot be used by exploits for data purposes either.

  We know about no user-space code that relies on pure PROT_EXEC
  mappings today, but binary loaders could start making use of this new
  feature to map binaries and libraries in a more secure fashion.

  There is other pending pkeys work that offers more high level system
  call APIs to manage protection keys - but those are not part of this
  pull request.

  Right now there's a Kconfig that controls this feature
  (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) that is default enabled
  (like most x86 CPU feature enablement code that has no runtime
  overhead), but it's not user-configurable at the moment.  If there's
  any serious problem with this then we can make it configurable and/or
  flip the default"

* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  x86/mm/pkeys: Fix mismerge of protection keys CPUID bits
  mm/pkeys: Fix siginfo ABI breakage caused by new u64 field
  x86/mm/pkeys: Fix access_error() denial of writes to write-only VMA
  mm/core, x86/mm/pkeys: Add execute-only protection keys support
  x86/mm/pkeys: Create an x86 arch_calc_vm_prot_bits() for VMA flags
  x86/mm/pkeys: Allow kernel to modify user pkey rights register
  x86/fpu: Allow setting of XSAVE state
  x86/mm: Factor out LDT init from context init
  mm/core, x86/mm/pkeys: Add arch_validate_pkey()
  mm/core, arch, powerpc: Pass a protection key in to calc_vm_flag_bits()
  x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU
  x86/mm/pkeys: Add Kconfig prompt to existing config option
  x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps
  x86/mm/pkeys: Dump PKRU with other kernel registers
  mm/core, x86/mm/pkeys: Differentiate instruction fetches
  x86/mm/pkeys: Optimize fault handling in access_error()
  mm/core: Do not enforce PKEY permissions on remote mm access
  um, pkeys: Add UML arch_*_access_permitted() methods
  mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
  x86/mm/gup: Simplify get_user_pages() PTE bit handling
  ...
2016-03-20 19:08:56 -07:00
Linus Torvalds
26660a4046 Merge branch 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull 'objtool' stack frame validation from Ingo Molnar:
 "This tree adds a new kernel build-time object file validation feature
  (ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation.
  It was written by and is maintained by Josh Poimboeuf.

  The motivation: there's a category of hard to find kernel bugs, most
  of them in assembly code (but also occasionally in C code), that
  degrades the quality of kernel stack dumps/backtraces.  These bugs are
  hard to detect at the source code level.  Such bugs result in
  incorrect/incomplete backtraces most of time - but can also in some
  rare cases result in crashes or other undefined behavior.

  The build time correctness checking is done via the new 'objtool'
  user-space utility that was written for this purpose and which is
  hosted in the kernel repository in tools/objtool/.  The tool's (very
  simple) UI and source code design is shaped after Git and perf and
  shares quite a bit of infrastructure with tools/perf (which tooling
  infrastructure sharing effort got merged via perf and is already
  upstream).  Objtool follows the well-known kernel coding style.

  Objtool does not try to check .c or .S files, it instead analyzes the
  resulting .o generated machine code from first principles: it decodes
  the instruction stream and interprets it.  (Right now objtool supports
  the x86-64 architecture.)

  From tools/objtool/Documentation/stack-validation.txt:

   "The kernel CONFIG_STACK_VALIDATION option enables a host tool named
    objtool which runs at compile time.  It has a "check" subcommand
    which analyzes every .o file and ensures the validity of its stack
    metadata.  It enforces a set of rules on asm code and C inline
    assembly code so that stack traces can be reliable.

    Currently it only checks frame pointer usage, but there are plans to
    add CFI validation for C files and CFI generation for asm files.

    For each function, it recursively follows all possible code paths
    and validates the correct frame pointer state at each instruction.

    It also follows code paths involving special sections, like
    .altinstructions, __jump_table, and __ex_table, which can add
    alternative execution paths to a given instruction (or set of
    instructions).  Similarly, it knows how to follow switch statements,
    for which gcc sometimes uses jump tables."

  When this new kernel option is enabled (it's disabled by default), the
  tool, if it finds any suspicious assembly code pattern, outputs
  warnings in compiler warning format:

    warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch
    warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup
    warning: objtool:__schedule()+0x3c0: duplicate frame pointer save
    warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer

  ... so that scripts that pick up compiler warnings will notice them.
  All known warnings triggered by the tool are fixed by the tree, most
  of the commits in fact prepare the kernel to be warning-free.  Most of
  them are bugfixes or cleanups that stand on their own, but there are
  also some annotations of 'special' stack frames for justified cases
  such entries to JIT-ed code (BPF) or really special boot time code.

  There are two other long-term motivations behind this tool as well:

   - To improve the quality and reliability of kernel stack frames, so
     that they can be used for optimized live patching.

   - To create independent infrastructure to check the correctness of
     CFI stack frames at build time.  CFI debuginfo is notoriously
     unreliable and we cannot use it in the kernel as-is without extra
     checking done both on the kernel side and on the build side.

  The quality of kernel stack frames matters to debuggability as well,
  so IMO we can merge this without having to consider the live patching
  or CFI debuginfo angle"

* 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  objtool: Only print one warning per function
  objtool: Add several performance improvements
  tools: Copy hashtable.h into tools directory
  objtool: Fix false positive warnings for functions with multiple switch statements
  objtool: Rename some variables and functions
  objtool: Remove superflous INIT_LIST_HEAD
  objtool: Add helper macros for traversing instructions
  objtool: Fix false positive warnings related to sibling calls
  objtool: Compile with debugging symbols
  objtool: Detect infinite recursion
  objtool: Prevent infinite recursion in noreturn detection
  objtool: Detect and warn if libelf is missing and don't break the build
  tools: Support relative directory path for 'O='
  objtool: Support CROSS_COMPILE
  x86/asm/decoder: Use explicitly signed chars
  objtool: Enable stack metadata validation on 64-bit x86
  objtool: Add CONFIG_STACK_VALIDATION option
  objtool: Add tool to perform compile-time stack metadata validation
  x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard
  sched: Always inline context_switch()
  ...
2016-03-20 18:23:21 -07:00
Linus Torvalds
51b3eae8db Merge branch 'stable-4.6' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore:
 "A small set of patches for audit this time; just three in total and
  one is a spelling fix.

  The two patches with actual content are designed to help prevent new
  instances of auditd from displacing an existing, functioning auditd
  and to generate a log of the attempt.  Not to worry, dead/stuck auditd
  instances can still be replaced by a new instance without problem.

  Nothing controversial, and everything passes our regression suite"

* 'stable-4.6' of git://git.infradead.org/users/pcmoore/audit:
  audit: Fix typo in comment
  audit: log failed attempts to change audit_pid configuration
  audit: stop an old auditd being starved out by a new auditd
2016-03-19 17:52:49 -07:00
Linus Torvalds
1200b6809d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Support more Realtek wireless chips, from Jes Sorenson.

   2) New BPF types for per-cpu hash and arrap maps, from Alexei
      Starovoitov.

   3) Make several TCP sysctls per-namespace, from Nikolay Borisov.

   4) Allow the use of SO_REUSEPORT in order to do per-thread processing
   of incoming TCP/UDP connections.  The muxing can be done using a
   BPF program which hashes the incoming packet.  From Craig Gallek.

   5) Add a multiplexer for TCP streams, to provide a messaged based
      interface.  BPF programs can be used to determine the message
      boundaries.  From Tom Herbert.

   6) Add 802.1AE MACSEC support, from Sabrina Dubroca.

   7) Avoid factorial complexity when taking down an inetdev interface
      with lots of configured addresses.  We were doing things like
      traversing the entire address less for each address removed, and
      flushing the entire netfilter conntrack table for every address as
      well.

   8) Add and use SKB bulk free infrastructure, from Jesper Brouer.

   9) Allow offloading u32 classifiers to hardware, and implement for
      ixgbe, from John Fastabend.

  10) Allow configuring IRQ coalescing parameters on a per-queue basis,
      from Kan Liang.

  11) Extend ethtool so that larger link mode masks can be supported.
      From David Decotigny.

  12) Introduce devlink, which can be used to configure port link types
      (ethernet vs Infiniband, etc.), port splitting, and switch device
      level attributes as a whole.  From Jiri Pirko.

  13) Hardware offload support for flower classifiers, from Amir Vadai.

  14) Add "Local Checksum Offload".  Basically, for a tunneled packet
      the checksum of the outer header is 'constant' (because with the
      checksum field filled into the inner protocol header, the payload
      of the outer frame checksums to 'zero'), and we can take advantage
      of that in various ways.  From Edward Cree"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits)
  bonding: fix bond_get_stats()
  net: bcmgenet: fix dma api length mismatch
  net/mlx4_core: Fix backward compatibility on VFs
  phy: mdio-thunder: Fix some Kconfig typos
  lan78xx: add ndo_get_stats64
  lan78xx: handle statistics counter rollover
  RDS: TCP: Remove unused constant
  RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket
  net: smc911x: convert pxa dma to dmaengine
  team: remove duplicate set of flag IFF_MULTICAST
  bonding: remove duplicate set of flag IFF_MULTICAST
  net: fix a comment typo
  ethernet: micrel: fix some error codes
  ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it
  bpf, dst: add and use dst_tclassid helper
  bpf: make skb->tc_classid also readable
  net: mvneta: bm: clarify dependencies
  cls_bpf: reset class and reuse major in da
  ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c
  ldmvsw: Add ldmvsw.c driver code
  ...
2016-03-19 10:05:34 -07:00
Linus Torvalds
6b5f04b6cf Merge branch 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "cgroup changes for v4.6-rc1.  No userland visible behavior changes in
  this pull request.  I'll send out a separate pull request for the
  addition of cgroup namespace support.

   - The biggest change is the revamping of cgroup core task migration
     and controller handling logic.  There are quite a few places where
     controllers and tasks are manipulated.  Previously, many of those
     places implemented custom operations for each specific use case
     assuming specific starting conditions.  While this worked, it makes
     the code fragile and difficult to follow.

     The bulk of this pull request restructures these operations so that
     most related operations are performed through common helpers which
     implement recursive (subtrees are always processed consistently)
     and idempotent (they make cgroup hierarchy converge to the target
     state rather than performing operations assuming specific starting
     conditions).  This makes the code a lot easier to understand,
     verify and extend.

   - Implicit controller support is added.  This is primarily for using
     perf_event on the v2 hierarchy so that perf can match cgroup v2
     path without requiring the user to do anything special.  The kernel
     portion of perf_event changes is acked but userland changes are
     still pending review.

   - cgroup_no_v1= boot parameter added to ease testing cgroup v2 in
     certain environments.

   - There is a regression introduced during v4.4 devel cycle where
     attempts to migrate zombie tasks can mess up internal object
     management.  This was fixed earlier this week and included in this
     pull request w/ stable cc'd.

   - Misc non-critical fixes and improvements"

* 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (44 commits)
  cgroup: avoid false positive gcc-6 warning
  cgroup: ignore css_sets associated with dead cgroups during migration
  Documentation: cgroup v2: Trivial heading correction.
  cgroup: implement cgroup_subsys->implicit_on_dfl
  cgroup: use css_set->mg_dst_cgrp for the migration target cgroup
  cgroup: make cgroup[_taskset]_migrate() take cgroup_root instead of cgroup
  cgroup: move migration destination verification out of cgroup_migrate_prepare_dst()
  cgroup: fix incorrect destination cgroup in cgroup_update_dfl_csses()
  cgroup: Trivial correction to reflect controller.
  cgroup: remove stale item in cgroup-v1 document INDEX file.
  cgroup: update css iteration in cgroup_update_dfl_csses()
  cgroup: allocate 2x cgrp_cset_links when setting up a new root
  cgroup: make cgroup_calc_subtree_ss_mask() take @this_ss_mask
  cgroup: reimplement rebind_subsystems() using cgroup_apply_control() and friends
  cgroup: use cgroup_apply_enable_control() in cgroup creation path
  cgroup: combine cgroup_mutex locking and offline css draining
  cgroup: factor out cgroup_{apply|finalize}_control() from cgroup_subtree_control_write()
  cgroup: introduce cgroup_{save|propagate|restore}_control()
  cgroup: make cgroup_drain_offline() and cgroup_apply_control_{disable|enable}() recursive
  cgroup: factor out cgroup_apply_control_enable() from cgroup_subtree_control_write()
  ...
2016-03-18 20:25:49 -07:00
Linus Torvalds
ef504fa591 Merge branch 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue updates from Tejun Heo:
 "Three trivial workqueue changes"

* 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Fix comment for work_on_cpu()
  sched/core: Get rid of 'cpu' argument in wq_worker_sleeping()
  workqueue: Replace usage of init_name with dev_set_name()
2016-03-18 20:05:39 -07:00
Linus Torvalds
814a2bf957 Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton:

 - a couple of hotfixes

 - the rest of MM

 - a new timer slack control in procfs

 - a couple of procfs fixes

 - a few misc things

 - some printk tweaks

 - lib/ updates, notably to radix-tree.

 - add my and Nick Piggin's old userspace radix-tree test harness to
   tools/testing/radix-tree/.  Matthew said it was a godsend during the
   radix-tree work he did.

 - a few code-size improvements, switching to __always_inline where gcc
   screwed up.

 - partially implement character sets in sscanf

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
  sscanf: implement basic character sets
  lib/bug.c: use common WARN helper
  param: convert some "on"/"off" users to strtobool
  lib: add "on"/"off" support to kstrtobool
  lib: update single-char callers of strtobool()
  lib: move strtobool() to kstrtobool()
  include/linux/unaligned: force inlining of byteswap operations
  include/uapi/linux/byteorder, swab: force inlining of some byteswap operations
  include/asm-generic/atomic-long.h: force inlining of some atomic_long operations
  usb: common: convert to use match_string() helper
  ide: hpt366: convert to use match_string() helper
  ata: hpt366: convert to use match_string() helper
  power: ab8500: convert to use match_string() helper
  power: charger_manager: convert to use match_string() helper
  drm/edid: convert to use match_string() helper
  pinctrl: convert to use match_string() helper
  device property: convert to use match_string() helper
  lib/string: introduce match_string() helper
  radix-tree tests: add test for radix_tree_iter_next
  radix-tree tests: add regression3 test
  ...
2016-03-18 19:26:54 -07:00
Dmitry Safonov
741f3a69f1 tracing: Remove redundant reset per-CPU buff in irqsoff tracer
There is no reason to do it twice: from commit b6f11df26f
("trace: Call tracing_reset_online_cpus before tracer->init()")
resetting of per-CPU buffers done before tracer->init() call.

tracer->init() calls {irqs,preempt,preemptirqs}off_tracer_init() and it
calls __irqsoff_tracer_init(), which resets per-CPU ringbuffer second
time.
It's slowpath, but anyway.

Link: http://lkml.kernel.org/r/1445278226-16187-1-git-send-email-0x7f454c46@gmail.com

Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 16:39:11 -04:00
Steven Rostedt (Red Hat)
a29054d947 tracing: Fix crash from reading trace_pipe with sendfile
If tracing contains data and the trace_pipe file is read with sendfile(),
then it can trigger a NULL pointer dereference and various BUG_ON within the
VM code.

There's a patch to fix this in the splice_to_pipe() code, but it's also a
good idea to not let that happen from trace_pipe either.

Link: http://lkml.kernel.org/r/1457641146-9068-1-git-send-email-rabin@rab.in

Cc: stable@vger.kernel.org # 2.6.30+
Reported-by: Rabin Vincent <rabin.vincent@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 15:51:42 -04:00
Steven Rostedt (Red Hat)
cb86e05390 tracing: Have preempt(irqs)off trace preempt disabled functions
Joel Fernandes reported that the function tracing of preempt disabled
sections was not being reported when running either the preemptirqsoff or
preemptoff tracers. This was due to the fact that the function tracer
callback for those tracers checked if irqs were disabled before tracing. But
this fails when we want to trace preempt off locations as well.

Joel explained that he wanted to see funcitons where interrupts are enabled
but preemption was disabled. The expected output he wanted:

   <...>-2265    1d.h1 3419us : preempt_count_sub <-irq_exit
   <...>-2265    1d..1 3419us : __do_softirq <-irq_exit
   <...>-2265    1d..1 3419us : msecs_to_jiffies <-__do_softirq
   <...>-2265    1d..1 3420us : irqtime_account_irq <-__do_softirq
   <...>-2265    1d..1 3420us : __local_bh_disable_ip <-__do_softirq
   <...>-2265    1..s1 3421us : run_timer_softirq <-__do_softirq
   <...>-2265    1..s1 3421us : hrtimer_run_pending <-run_timer_softirq
   <...>-2265    1..s1 3421us : _raw_spin_lock_irq <-run_timer_softirq
   <...>-2265    1d.s1 3422us : preempt_count_add <-_raw_spin_lock_irq
   <...>-2265    1d.s2 3422us : _raw_spin_unlock_irq <-run_timer_softirq
   <...>-2265    1..s2 3422us : preempt_count_sub <-_raw_spin_unlock_irq
   <...>-2265    1..s1 3423us : rcu_bh_qs <-__do_softirq
   <...>-2265    1d.s1 3423us : irqtime_account_irq <-__do_softirq
   <...>-2265    1d.s1 3423us : __local_bh_enable <-__do_softirq

There's a comment saying that the irq disabled check is because there's a
possible race that tracing_cpu may be set when the function is executed. But
I don't remember that race. For now, I added a check for preemption being
enabled too to not record the function, as there would be no race if that
was the case. I need to re-investigate this, as I'm now thinking that the
tracing_cpu will always be correct. But no harm in keeping the check for
now, except for the slight performance hit.

Link: http://lkml.kernel.org/r/1457770386-88717-1-git-send-email-agnel.joel@gmail.com

Fixes: 5e6d2b9cfa "tracing: Use one prologue for the preempt irqs off tracer function tracers"
Cc: stable@vget.kernel.org # 2.6.37+
Reported-by: Joel Fernandes <agnel.joel@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 12:47:38 -04:00
Chunyu Hu
c8ca003b2f tracing: Fix return while holding a lock in register_tracer()
commit d39cdd2036 ("tracing: Make tracer_flags use the right set_flag
callback")  introduces a potential mutex deadlock issue, as it forgets to
free the mutex when allocaing the tracer_flags gets fail.

The issue was found by Dan Carpenter through Smatch static code check tool.

Link: http://lkml.kernel.org/r/1457958941-30265-1-git-send-email-chuhu@redhat.com

Fixes: d39cdd2036 ("tracing: Make tracer_flags use the right set_flag callback")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 10:36:21 -04:00
Geliang Tang
6363c6b599 ftrace: Use kasprintf() in ftrace_profile_tracefs()
Use kasprintf() instead of kmalloc() and snprintf().

Link: http://lkml.kernel.org/r/135a7bc36e51fd9eaa57124dd2140285b771f738.1458050835.git.geliangtang@163.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 10:31:34 -04:00
Jiri Olsa
7f50d06bb6 ftrace: Update dynamic ftrace calls only if necessary
Currently dynamic ftrace calls are updated any time
the ftrace_ops is un/registered. If we do  this update
only when it's needed, we save lot of time for perf
system wide ftrace function sampling/counting.

The reason is that for system wide sampling/counting,
perf creates event for each cpu in the system.

Each event then registers separate copy of ftrace_ops,
which ends up in FTRACE_UPDATE_CALLS updates. On servers
with many cpus that means serious stall (240 cpus server):

Counting:
  # time ./perf stat -e ftrace:function -a sleep 1

   Performance counter stats for 'system wide':

              370,663      ftrace:function

          1.401427505 seconds time elapsed

  real    3m51.743s
  user    0m0.023s
  sys     3m48.569s

Sampling:
  # time ./perf record -e ftrace:function -a sleep 1
  [ perf record: Woken up 0 times to write data ]
  Warning:
  Processed 141200 events and lost 5 chunks!

  [ perf record: Captured and wrote 10.703 MB perf.data (135950 samples) ]

  real    2m31.429s
  user    0m0.213s
  sys     2m29.494s

There's no reason to do the FTRACE_UPDATE_CALLS update
for each event in perf case, because all the ftrace_ops
always share the same filter, so the updated calls are
always the same.

It's required that only first ftrace_ops registration
does the FTRACE_UPDATE_CALLS update (also sometimes
the second if the first one used the trampoline), but
the rest can be only cheaply linked into the ftrace_ops
list.

Counting:
  # time ./perf stat -e ftrace:function -a sleep 1

   Performance counter stats for 'system wide':

             398,571      ftrace:function

         1.377503733 seconds time elapsed

  real    0m2.787s
  user    0m0.005s
  sys     0m1.883s

Sampling:
  # time ./perf record -e ftrace:function -a sleep 1
  [ perf record: Woken up 0 times to write data ]
  Warning:
  Processed 261730 events and lost 9 chunks!

  [ perf record: Captured and wrote 19.907 MB perf.data (256293 samples) ]

  real    1m31.948s
  user    0m0.309s
  sys     1m32.051s

Link: http://lkml.kernel.org/r/1458138873-1553-6-git-send-email-jolsa@kernel.org

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 10:30:34 -04:00
Jiri Olsa
84b6d3e614 ftrace: Make ftrace_hash_rec_enable return update bool
Change __ftrace_hash_rec_update to return true in case
we need to update dynamic ftrace call records. It return
false in case no update is needed.

Link: http://lkml.kernel.org/r/1458138873-1553-5-git-send-email-jolsa@kernel.org

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 10:30:15 -04:00
Linus Torvalds
0f49fc95b8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatching update from Jiri Kosina:

 - cleanup of module notifiers; this depends on a module.c cleanup which
   has been acked by Rusty; from Jessica Yu

 - small assorted fixes and MAINTAINERS update

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch/module: remove livepatch module notifier
  modules: split part of complete_formation() into prepare_coming_module()
  livepatch: Update maintainers
  livepatch: Fix the error message about unresolvable ambiguity
  klp: remove CONFIG_LIVEPATCH dependency from klp headers
  klp: remove superfluous errors in asm/livepatch.h
2016-03-17 21:46:32 -07:00
Linus Torvalds
49dc2b7173 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  drivers/rtc: broken link fix
  drm/i915 Fix typos in i915_gem_fence.c
  Docs: fix missing word in REPORTING-BUGS
  lib+mm: fix few spelling mistakes
  MAINTAINERS: add git URL for APM driver
  treewide: Fix typo in printk
2016-03-17 21:38:27 -07:00
Josh Poimboeuf
2553b67a1f lib/bug.c: use common WARN helper
The traceoff_on_warning option doesn't have any effect on s390, powerpc,
arm64, parisc, and sh because there are two different types of WARN
implementations:

1) The above mentioned architectures treat WARN() as a special case of a
   BUG() exception.  They handle warnings in report_bug() in lib/bug.c.

2) All other architectures just call warn_slowpath_*() directly.  Their
   warnings are handled in warn_slowpath_common() in kernel/panic.c.

Support traceoff_on_warning on all architectures and prevent any future
divergence by using a single common function to emit the warning.

Also remove the '()' from '%pS()', because the parentheses look funky:

  [   45.607629] WARNING: at /root/warn_mod/warn_mod.c:17 .init_dummy+0x20/0x40 [warn_mod]()

Reported-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Kees Cook
4cc7ecb7f2 param: convert some "on"/"off" users to strtobool
This changes several users of manual "on"/"off" parsing to use
strtobool.

Some side-effects:
- these uses will now parse y/n/1/0 meaningfully too
- the early_param uses will now bubble up parse errors

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Amitkumar Karwar <akarwar@marvell.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Joe Perches <joe@perches.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nishant Sarmukadam <nishants@marvell.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steve French <sfrench@samba.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Ivan Delalande
f468908bb5 printk: add clear_idx symbol to vmcoreinfo
This allows us to extract from the vmcore only the messages emitted
since the last time the ring buffer was cleared.  We just have to make
sure its value is always up-to-date, when old messages are discarded to
free space in log_make_free_space() for example.

Signed-off-by: Zeyu Zhao <zzy8200@gmail.com>
Signed-off-by: Ivan Delalande <colona@arista.com>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Sergey Senozhatsky
adaf6590ee printk: check CON_ENABLED in have_callable_console()
have_callable_console() must also test CON_ENABLED bit, not just
CON_ANYTIME.  We may have disabled CON_ANYTIME console so printk can
wrongly assume that it's safe to call_console_drivers().

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Jan Kara <jack@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kyle McMartin <kyle@kernel.org>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Calvin Owens <calvinowens@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Sergey Senozhatsky
6b97a20d3a printk: set may_schedule for some of console_trylock() callers
console_unlock() allows to cond_resched() if its caller has set
`console_may_schedule' to 1, since 8d91f8b153 ("printk: do
cond_resched() between lines while outputting to consoles").

The rules are:
-- console_lock() always sets `console_may_schedule' to 1
-- console_trylock() always sets `console_may_schedule' to 0

However, console_trylock() callers (among them is printk()) do not
always call printk() from atomic contexts, and some of them can
cond_resched() in console_unlock(), so console_trylock() can set
`console_may_schedule' to 1 for such processes.

For !CONFIG_PREEMPT_COUNT kernels, however, console_trylock() always
sets `console_may_schedule' to 0.

It's possible to drop explicit preempt_disable()/preempt_enable() in
vprintk_emit(), because console_unlock() and console_trylock() are now
smart enough:
 a) console_unlock() does not cond_resched() when it's unsafe
    (console_trylock() takes care of that)
 b) console_unlock() does can_use_console() check.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Jan Kara <jack@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kyle McMartin <kyle@kernel.org>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Calvin Owens <calvinowens@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Sergey Senozhatsky
a8199371af printk: move can_use_console() out of console_trylock_for_printk()
console_unlock() allows to cond_resched() if its caller has set
`console_may_schedule' to 1 (this functionality is present since
8d91f8b153 ("printk: do cond_resched() between lines while outputting
to consoles").

The rules are:
-- console_lock() always sets `console_may_schedule' to 1
-- console_trylock() always sets `console_may_schedule' to 0

printk() calls console_unlock() with preemption desabled, which
basically can lead to RCU stalls, watchdog soft lockups, etc.  if
something is simultaneously calling printk() frequent enough (IOW,
console_sem owner always has new data to send to console divers and
can't leave console_unlock() for a long time).

printk()->console_trylock() callers do not necessarily execute in atomic
contexts, and some of them can cond_resched() in console_unlock().
console_trylock() can set `console_may_schedule' to 1 (allow
cond_resched() later in consoe_unlock()) when it's safe.

This patch (of 3):

vprintk_emit() disables preemption around console_trylock_for_printk()
and console_unlock() calls for a strong reason -- can_use_console()
check.  The thing is that vprintl_emit() can be called on a CPU that is
not fully brought up yet (!cpu_online()), which potentially can cause
problems if console driver wants to access per-cpu data.  A console
driver can explicitly state that it's safe to call it from !online cpu
by setting CON_ANYTIME bit in console ->flags.  That's why for
!cpu_online() can_use_console() iterates all the console to find out if
there is a CON_ANYTIME console, otherwise console_unlock() must be
avoided.

can_use_console() ensures that console_unlock() call is safe in
vprintk_emit() only; console_lock() and console_trylock() are not
covered by this check.  Even though call_console_drivers(), invoked from
console_cont_flush() and console_unlock(), tests `!cpu_online() &&
CON_ANYTIME' for_each_console(), it may be too late, which can result in
messages loss.

Assume that we have 2 cpus -- CPU0 is online, CPU1 is !online, and no
CON_ANYTIME consoles available.

CPU0 online                        CPU1 !online
                                 console_trylock()
                                 ...
                                 console_unlock()
                                   console_cont_flush
                                     spin_lock logbuf_lock
                                     if (!cont.len) {
                                        spin_unlock logbuf_lock
                                        return
                                     }
                                   for (;;) {
vprintk_emit
  spin_lock logbuf_lock
  log_store
  spin_unlock logbuf_lock
                                     spin_lock logbuf_lock
  !console_trylock_for_printk        msg_print_text
 return                              console_idx = log_next()
                                     console_seq++
                                     console_prev = msg->flags
                                     spin_unlock logbuf_lock

                                     call_console_drivers()
                                       for_each_console(con) {
                                         if (!cpu_online() &&
                                             !(con->flags & CON_ANYTIME))
                                                 continue;
                                         }
                                   /*
                                    * no message printed, we lost it
                                    */
vprintk_emit
  spin_lock logbuf_lock
  log_store
  spin_unlock logbuf_lock
  !console_trylock_for_printk
 return
                                   /*
                                    * go to the beginning of the loop,
                                    * find out there are new messages,
                                    * lose it
                                    */
                                   }

console_trylock()/console_lock() call on CPU1 may come from cpu
notifiers registered on that CPU.  Since notifiers are not getting
unregistered when CPU is going DOWN, all of the notifiers receive
notifications during CPU UP.  For example, on my x86_64, I see around 50
notification sent from offline CPU to itself

 [swapper/2] from cpu:2 to:2 action:CPU_STARTING hotplug_hrtick
 [swapper/2] from cpu:2 to:2 action:CPU_STARTING blk_mq_main_cpu_notify
 [swapper/2] from cpu:2 to:2 action:CPU_STARTING blk_mq_queue_reinit_notify
 [swapper/2] from cpu:2 to:2 action:CPU_STARTING console_cpu_notify

while doing
  echo 0 > /sys/devices/system/cpu/cpu2/online
  echo 1 > /sys/devices/system/cpu/cpu2/online

So grabbing the console_sem lock while CPU is !online is possible,
in theory.

This patch moves can_use_console() check out of
console_trylock_for_printk().  Instead it calls it in console_unlock(),
so now console_lock()/console_unlock() are also 'protected' by
can_use_console().  This also means that console_trylock_for_printk() is
not really needed anymore and can be removed.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Jan Kara <jack@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kyle McMartin <kyle@kernel.org>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Calvin Owens <calvinowens@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
John Stultz
da8b44d5a9 timer: convert timer_slack_ns from unsigned long to u64
This patchset introduces a /proc/<pid>/timerslack_ns interface which
would allow controlling processes to be able to set the timerslack value
on other processes in order to save power by avoiding wakeups (Something
Android currently does via out-of-tree patches).

The first patch tries to fix the internal timer_slack_ns usage which was
defined as a long, which limits the slack range to ~4 seconds on 32bit
systems.  It converts it to a u64, which provides the same basically
unlimited slack (500 years) on both 32bit and 64bit machines.

The second patch introduces the /proc/<pid>/timerslack_ns interface
which allows the full 64bit slack range for a task to be read or set on
both 32bit and 64bit machines.

With these two patches, on a 32bit machine, after setting the slack on
bash to 10 seconds:

$ time sleep 1

real    0m10.747s
user    0m0.001s
sys     0m0.005s

The first patch is a little ugly, since I had to chase the slack delta
arguments through a number of functions converting them to u64s.  Let me
know if it makes sense to break that up more or not.

Other than that things are fairly straightforward.

This patch (of 2):

The timer_slack_ns value in the task struct is currently a unsigned
long.  This means that on 32bit applications, the maximum slack is just
over 4 seconds.  However, on 64bit machines, its much much larger (~500
years).

This disparity could make application development a little (as well as
the default_slack) to a u64.  This means both 32bit and 64bit systems
have the same effective internal slack range.

Now the existing ABI via PR_GET_TIMERSLACK and PR_SET_TIMERSLACK specify
the interface as a unsigned long, so we preserve that limitation on
32bit systems, where SET_TIMERSLACK can only set the slack to a unsigned
long value, and GET_TIMERSLACK will return ULONG_MAX if the slack is
actually larger then what can be stored by an unsigned long.

This patch also modifies hrtimer functions which specified the slack
delta as a unsigned long.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Oren Laadan <orenl@cellrox.com>
Cc: Ruchi Kandoi <kandoiruchi@google.com>
Cc: Rom Lemarchand <romlem@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Johannes Weiner
795ae7a0de mm: scale kswapd watermarks in proportion to memory
In machines with 140G of memory and enterprise flash storage, we have
seen read and write bursts routinely exceed the kswapd watermarks and
cause thundering herds in direct reclaim.  Unfortunately, the only way
to tune kswapd aggressiveness is through adjusting min_free_kbytes - the
system's emergency reserves - which is entirely unrelated to the
system's latency requirements.  In order to get kswapd to maintain a
250M buffer of free memory, the emergency reserves need to be set to 1G.
That is a lot of memory wasted for no good reason.

On the other hand, it's reasonable to assume that allocation bursts and
overall allocation concurrency scale with memory capacity, so it makes
sense to make kswapd aggressiveness a function of that as well.

Change the kswapd watermark scale factor from the currently fixed 25% of
the tunable emergency reserve to a tunable 0.1% of memory.

Beyond 1G of memory, this will produce bigger watermark steps than the
current formula in default settings.  Ensure that the new formula never
chooses steps smaller than that, i.e.  25% of the emergency reserve.

On a 140G machine, this raises the default watermark steps - the
distance between min and low, and low and high - from 16M to 143M.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Vladimir Davydov
12580e4b54 mm: memcontrol: report kernel stack usage in cgroup2 memory.stat
Show how much memory is allocated to kernel stacks.

Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Joshua Hunt
a1ee1932aa watchdog: don't run proc_watchdog_update if new value is same as old
While working on a script to restore all sysctl params before a series of
tests I found that writing any value into the
/proc/sys/kernel/{nmi_watchdog,soft_watchdog,watchdog,watchdog_thresh}
causes them to call proc_watchdog_update().

  NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter.
  NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter.
  NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter.
  NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter.

There doesn't appear to be a reason for doing this work every time a write
occurs, so only do it when the values change.

Signed-off-by: Josh Hunt <johunt@akamai.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: <stable@vger.kernel.org>	[4.1.x+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Linus Torvalds
96b9b1c956 TTY/Serial patches for 4.6-rc1
Here's the big tty/serial driver pull request for 4.6-rc1.
 
 Lots of changes in here, Peter has been on a tear again, with lots of
 refactoring and bugs fixes, many thanks to the great work he has been
 doing.  Lots of driver updates and fixes as well, full details in the
 shortlog.
 
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here's the big tty/serial driver pull request for 4.6-rc1.

  Lots of changes in here, Peter has been on a tear again, with lots of
  refactoring and bugs fixes, many thanks to the great work he has been
  doing.  Lots of driver updates and fixes as well, full details in the
  shortlog.

  All have been in linux-next for a while with no reported issues"

* tag 'tty-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (220 commits)
  serial: 8250: describe CONFIG_SERIAL_8250_RSA
  serial: samsung: optimize UART rx fifo access routine
  serial: pl011: add mark/space parity support
  serial: sa1100: make sa1100_register_uart_fns a function
  tty: serial: 8250: add MOXA Smartio MUE boards support
  serial: 8250: convert drivers to use up_to_u8250p()
  serial: 8250/mediatek: fix building with SERIAL_8250=m
  serial: 8250/ingenic: fix building with SERIAL_8250=m
  serial: 8250/uniphier: fix modular build
  Revert "drivers/tty/serial: make 8250/8250_ingenic.c explicitly non-modular"
  Revert "drivers/tty/serial: make 8250/8250_mtk.c explicitly non-modular"
  serial: mvebu-uart: initial support for Armada-3700 serial port
  serial: mctrl_gpio: Add missing module license
  serial: ifx6x60: avoid uninitialized variable use
  tty/serial: at91: fix bad offset for UART timeout register
  tty/serial: at91: restore dynamic driver binding
  serial: 8250: Add hardware dependency to RT288X option
  TTY, devpts: document pty count limiting
  tty: goldfish: support platform_device with id -1
  drivers: tty: goldfish: Add device tree bindings
  ...
2016-03-17 13:53:25 -07:00
Linus Torvalds
bb7aeae3d6 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security layer updates from James Morris:
 "There are a bunch of fixes to the TPM, IMA, and Keys code, with minor
  fixes scattered across the subsystem.

  IMA now requires signed policy, and that policy is also now measured
  and appraised"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (67 commits)
  X.509: Make algo identifiers text instead of enum
  akcipher: Move the RSA DER encoding check to the crypto layer
  crypto: Add hash param to pkcs1pad
  sign-file: fix build with CMS support disabled
  MAINTAINERS: update tpmdd urls
  MODSIGN: linux/string.h should be #included to get memcpy()
  certs: Fix misaligned data in extra certificate list
  X.509: Handle midnight alternative notation in GeneralizedTime
  X.509: Support leap seconds
  Handle ISO 8601 leap seconds and encodings of midnight in mktime64()
  X.509: Fix leap year handling again
  PKCS#7: fix unitialized boolean 'want'
  firmware: change kernel read fail to dev_dbg()
  KEYS: Use the symbol value for list size, updated by scripts/insert-sys-cert
  KEYS: Reserve an extra certificate symbol for inserting without recompiling
  modsign: hide openssl output in silent builds
  tpm_tis: fix build warning with tpm_tis_resume
  ima: require signed IMA policy
  ima: measure and appraise the IMA policy itself
  ima: load policy using path
  ...
2016-03-17 11:33:45 -07:00
Jessica Yu
7e545d6eca livepatch/module: remove livepatch module notifier
Remove the livepatch module notifier in favor of directly enabling and
disabling patches to modules in the module loader. Hard-coding the
function calls ensures that ftrace_module_enable() is run before
klp_module_coming() during module load, and that klp_module_going() is
run before ftrace_release_mod() during module unload. This way, ftrace
and livepatch code is run in the correct order during the module
load/unload sequence without dependence on the module notifier call chain.

Signed-off-by: Jessica Yu <jeyu@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2016-03-17 09:45:10 +01:00
Jessica Yu
4c973d1620 modules: split part of complete_formation() into prepare_coming_module()
Put all actions in complete_formation() that are performed after
module->state is set to MODULE_STATE_COMING into a separate function
prepare_coming_module(). This split prepares for the removal of the
livepatch module notifiers in favor of hard-coding function calls to
klp_module_{coming,going} in the module loader.

The complete_formation -> prepare_coming_module split will also make error
handling easier since we can jump to the appropriate error label to do any
module GOING cleanup after all the COMING-actions have completed.

Signed-off-by: Jessica Yu <jeyu@redhat.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2016-03-17 09:45:09 +01:00
Linus Torvalds
8759957b77 libnvdimm for 4.6
1/ Asynchronous address range scrub:
 Given the capacities of next generation persistent memory devices a
 scrub operation to find all poison may take 10s of seconds.  We want
 this scrub work to be done asynchronously with the rest of system
 initialization, so we move it out of line from the NFIT probing, i.e.
 acpi_nfit_add().
 
 2/ Clear poison:
 ACPI 6.1 introduces the ability to send "clear error" commands to the
 ACPI0012:00 device representing the root of an "nvdimm bus".  Similar to
 relocating a bad block on a disk, this support clears media errors in
 response to a write.
 
 3/ Persistent memory resource tracking:
 A persistent memory range may be designated as simply "reserved" by
 platform firmware in the efi/e820 memory map.  Later when the NFIT
 driver loads it discovers that the range is "Persistent Memory".  The
 NFIT bus driver inserts a resource to advertise that "persistent"
 attribute in the system resource tree for /proc/iomem and
 kernel-internal usages.
 
 4/ Miscellaneous cleanups and fixes:
 Workaround section misaligned pmem ranges when allocating a struct page
 memmap, fix handling of the read-only case in the ioctl path, and clean
 up block device major number allocation.
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Merge tag 'libnvdimm-for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:

 - Asynchronous address range scrub:

     Given the capacities of next generation persistent memory devices a
     scrub operation to find all poison may take 10s of seconds.  We
     want this scrub work to be done asynchronously with the rest of
     system initialization, so we move it out of line from the NFIT
     probing, i.e. acpi_nfit_add().

 - Clear poison:

     ACPI 6.1 introduces the ability to send "clear error" commands to
     the ACPI0012:00 device representing the root of an "nvdimm bus".
     Similar to relocating a bad block on a disk, this support clears
     media errors in response to a write.

 - Persistent memory resource tracking:

     A persistent memory range may be designated as simply "reserved" by
     platform firmware in the efi/e820 memory map.  Later when the NFIT
     driver loads it discovers that the range is "Persistent Memory".

     The NFIT bus driver inserts a resource to advertise that
     "persistent" attribute in the system resource tree for /proc/iomem
     and kernel-internal usages.

 - Miscellaneous cleanups and fixes:

     Workaround section misaligned pmem ranges when allocating a struct
     page memmap, fix handling of the read-only case in the ioctl path,
     and clean up block device major number allocation.

* tag 'libnvdimm-for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (26 commits)
  libnvdimm, pmem: clear poison on write
  libnvdimm, pmem: fix kmap_atomic() leak in error path
  nvdimm/btt: don't allocate unused major device number
  nvdimm/blk: don't allocate unused major device number
  pmem: don't allocate unused major device number
  ACPI: Change NFIT driver to insert new resource
  resource: Export insert_resource and remove_resource
  resource: Add remove_resource interface
  resource: Change __request_region to inherit from immediate parent
  libnvdimm, pmem: fix ia64 build, use PHYS_PFN
  nfit, libnvdimm: clear poison command support
  libnvdimm, pfn: 'resource'-address and 'size' attributes for pfn devices
  libnvdimm, pmem: adjust for section collisions with 'System RAM'
  libnvdimm, pmem: fix 'pfn' support for section-misaligned namespaces
  libnvdimm: Fix security issue with DSM IOCTL.
  libnvdimm: Clean-up access mode check.
  tools/testing/nvdimm: expand ars unit testing
  nfit: disable userspace initiated ars during scrub
  nfit: scrub and register regions in a workqueue
  nfit, libnvdimm: async region scrub workqueue
  ...
2016-03-16 17:45:56 -07:00
Linus Torvalds
277edbabf6 Power management and ACPI material for v4.6-rc1, part 1
- Redesign of cpufreq governors and the intel_pstate driver to
    make them use callbacks invoked by the scheduler to trigger CPU
    frequency evaluation instead of using per-CPU deferrable timers
    for that purpose (Rafael Wysocki).
 
  - Reorganization and cleanup of cpufreq governor code to make it
    more straightforward and fix some concurrency problems in it
    (Rafael Wysocki, Viresh Kumar).
 
  - Cleanup and improvements of locking in the cpufreq core (Viresh
    Kumar).
 
  - Assorted cleanups in the cpufreq core (Rafael Wysocki, Viresh
    Kumar, Eric Biggers).
 
  - intel_pstate driver updates including fixes, optimizations and a
    modification to make it enable enable hardware-coordinated P-state
    selection (HWP) by default if supported by the processor (Philippe
    Longepe, Srinivas Pandruvada, Rafael Wysocki, Viresh Kumar, Felipe
    Franciosi).
 
  - Operating Performance Points (OPP) framework updates to improve
    its handling of voltage regulators and device clocks and updates
    of the cpufreq-dt driver on top of that (Viresh Kumar, Jon Hunter).
 
  - Updates of the powernv cpufreq driver to fix initialization
    and cleanup problems in it and correct its worker thread handling
    with respect to CPU offline, new powernv_throttle tracepoint
    (Shilpasri Bhat).
 
  - ACPI cpufreq driver optimization and cleanup (Rafael Wysocki).
 
  - ACPICA updates including one fix for a regression introduced
    by previos changes in the ACPICA code (Bob Moore, Lv Zheng,
    David Box, Colin Ian King).
 
  - Support for installing ACPI tables from initrd (Lv Zheng).
 
  - Optimizations of the ACPI CPPC code (Prashanth Prakash, Ashwin
    Chaugule).
 
  - Support for _HID(ACPI0010) devices (ACPI processor containers)
    and ACPI processor driver cleanups (Sudeep Holla).
 
  - Support for ACPI-based enumeration of the AMBA bus (Graeme Gregory,
    Aleksey Makarov).
 
  - Modification of the ACPI PCI IRQ management code to make it treat
    255 in the Interrupt Line register as "not connected" on x86 (as
    per the specification) and avoid attempts to use that value as
    a valid interrupt vector (Chen Fan).
 
  - ACPI APEI fixes related to resource leaks (Josh Hunt).
 
  - Removal of modularity from a few ACPI drivers (BGRT, GHES,
    intel_pmic_crc) that cannot be built as modules in practice (Paul
    Gortmaker).
 
  - PNP framework update to make it treat ACPI_RESOURCE_TYPE_SERIAL_BUS
    as a valid resource type (Harb Abdulhamid).
 
  - New device ID (future AMD I2C controller) in the ACPI driver for
    AMD SoCs (APD) and in the designware I2C driver (Xiangliang Yu).
 
  - Assorted ACPI cleanups (Colin Ian King, Kaiyen Chang, Oleg Drokin).
 
  - cpuidle menu governor optimization to avoid a square root
    computation in it (Rasmus Villemoes).
 
  - Fix for potential use-after-free in the generic device properties
    framework (Heikki Krogerus).
 
  - Updates of the generic power domains (genpd) framework including
    support for multiple power states of a domain, fixes and debugfs
    output improvements (Axel Haslam, Jon Hunter, Laurent Pinchart,
    Geert Uytterhoeven).
 
  - Intel RAPL power capping driver updates to reduce IPI overhead in
    it (Jacob Pan).
 
  - System suspend/hibernation code cleanups (Eric Biggers, Saurabh
    Sengar).
 
  - Year 2038 fix for the process freezer (Abhilash Jindal).
 
  - turbostat utility updates including new features (decoding of more
    registers and CPUID fields, sub-second intervals support, GFX MHz
    and RC6 printout, --out command line option), fixes (syscall jitter
    detection and workaround, reductioin of the number of syscalls made,
    fixes related to Xeon x200 processors, compiler warning fixes) and
    cleanups (Len Brown, Hubert Chrzaniuk, Chen Yu).
 
 /
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Merge tag 'pm+acpi-4.6-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "This time the majority of changes go into cpufreq and they are
  significant.

  First off, the way CPU frequency updates are triggered is different
  now.  Instead of having to set up and manage a deferrable timer for
  each CPU in the system to evaluate and possibly change its frequency
  periodically, cpufreq governors set up callbacks to be invoked by the
  scheduler on a regular basis (basically on utilization updates).  The
  "old" governors, "ondemand" and "conservative", still do all of their
  work in process context (although that is triggered by the scheduler
  now), but intel_pstate does it all in the callback invoked by the
  scheduler with no need for any additional asynchronous processing.

  Of course, this eliminates the overhead related to the management of
  all those timers, but also it allows the cpufreq governor code to be
  simplified quite a bit.  On top of that, the common code and data
  structures used by the "ondemand" and "conservative" governors are
  cleaned up and made more straightforward and some long-standing and
  quite annoying problems are addressed.  In particular, the handling of
  governor sysfs attributes is modified and the related locking becomes
  more fine grained which allows some concurrency problems to be avoided
  (particularly deadlocks with the core cpufreq code).

  In principle, the new mechanism for triggering frequency updates
  allows utilization information to be passed from the scheduler to
  cpufreq.  Although the current code doesn't make use of it, in the
  works is a new cpufreq governor that will make decisions based on the
  scheduler's utilization data.  That should allow the scheduler and
  cpufreq to work more closely together in the long run.

  In addition to the core and governor changes, cpufreq drivers are
  updated too.  Fixes and optimizations go into intel_pstate, the
  cpufreq-dt driver is updated on top of some modification in the
  Operating Performance Points (OPP) framework and there are fixes and
  other updates in the powernv cpufreq driver.

  Apart from the cpufreq updates there is some new ACPICA material,
  including a fix for a problem introduced by previous ACPICA updates,
  and some less significant changes in the ACPI code, like CPPC code
  optimizations, ACPI processor driver cleanups and support for loading
  ACPI tables from initrd.

  Also updated are the generic power domains framework, the Intel RAPL
  power capping driver and the turbostat utility and we have a bunch of
  traditional assorted fixes and cleanups.

  Specifics:

   - Redesign of cpufreq governors and the intel_pstate driver to make
     them use callbacks invoked by the scheduler to trigger CPU
     frequency evaluation instead of using per-CPU deferrable timers for
     that purpose (Rafael Wysocki).

   - Reorganization and cleanup of cpufreq governor code to make it more
     straightforward and fix some concurrency problems in it (Rafael
     Wysocki, Viresh Kumar).

   - Cleanup and improvements of locking in the cpufreq core (Viresh
     Kumar).

   - Assorted cleanups in the cpufreq core (Rafael Wysocki, Viresh
     Kumar, Eric Biggers).

   - intel_pstate driver updates including fixes, optimizations and a
     modification to make it enable enable hardware-coordinated P-state
     selection (HWP) by default if supported by the processor (Philippe
     Longepe, Srinivas Pandruvada, Rafael Wysocki, Viresh Kumar, Felipe
     Franciosi).

   - Operating Performance Points (OPP) framework updates to improve its
     handling of voltage regulators and device clocks and updates of the
     cpufreq-dt driver on top of that (Viresh Kumar, Jon Hunter).

   - Updates of the powernv cpufreq driver to fix initialization and
     cleanup problems in it and correct its worker thread handling with
     respect to CPU offline, new powernv_throttle tracepoint (Shilpasri
     Bhat).

   - ACPI cpufreq driver optimization and cleanup (Rafael Wysocki).

   - ACPICA updates including one fix for a regression introduced by
     previos changes in the ACPICA code (Bob Moore, Lv Zheng, David Box,
     Colin Ian King).

   - Support for installing ACPI tables from initrd (Lv Zheng).

   - Optimizations of the ACPI CPPC code (Prashanth Prakash, Ashwin
     Chaugule).

   - Support for _HID(ACPI0010) devices (ACPI processor containers) and
     ACPI processor driver cleanups (Sudeep Holla).

   - Support for ACPI-based enumeration of the AMBA bus (Graeme Gregory,
     Aleksey Makarov).

   - Modification of the ACPI PCI IRQ management code to make it treat
     255 in the Interrupt Line register as "not connected" on x86 (as
     per the specification) and avoid attempts to use that value as a
     valid interrupt vector (Chen Fan).

   - ACPI APEI fixes related to resource leaks (Josh Hunt).

   - Removal of modularity from a few ACPI drivers (BGRT, GHES,
     intel_pmic_crc) that cannot be built as modules in practice (Paul
     Gortmaker).

   - PNP framework update to make it treat ACPI_RESOURCE_TYPE_SERIAL_BUS
     as a valid resource type (Harb Abdulhamid).

   - New device ID (future AMD I2C controller) in the ACPI driver for
     AMD SoCs (APD) and in the designware I2C driver (Xiangliang Yu).

   - Assorted ACPI cleanups (Colin Ian King, Kaiyen Chang, Oleg Drokin).

   - cpuidle menu governor optimization to avoid a square root
     computation in it (Rasmus Villemoes).

   - Fix for potential use-after-free in the generic device properties
     framework (Heikki Krogerus).

   - Updates of the generic power domains (genpd) framework including
     support for multiple power states of a domain, fixes and debugfs
     output improvements (Axel Haslam, Jon Hunter, Laurent Pinchart,
     Geert Uytterhoeven).

   - Intel RAPL power capping driver updates to reduce IPI overhead in
     it (Jacob Pan).

   - System suspend/hibernation code cleanups (Eric Biggers, Saurabh
     Sengar).

   - Year 2038 fix for the process freezer (Abhilash Jindal).

   - turbostat utility updates including new features (decoding of more
     registers and CPUID fields, sub-second intervals support, GFX MHz
     and RC6 printout, --out command line option), fixes (syscall jitter
     detection and workaround, reductioin of the number of syscalls
     made, fixes related to Xeon x200 processors, compiler warning
     fixes) and cleanups (Len Brown, Hubert Chrzaniuk, Chen Yu)"

* tag 'pm+acpi-4.6-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (182 commits)
  tools/power turbostat: bugfix: TDP MSRs print bits fixing
  tools/power turbostat: correct output for MSR_NHM_SNB_PKG_CST_CFG_CTL dump
  tools/power turbostat: call __cpuid() instead of __get_cpuid()
  tools/power turbostat: indicate SMX and SGX support
  tools/power turbostat: detect and work around syscall jitter
  tools/power turbostat: show GFX%rc6
  tools/power turbostat: show GFXMHz
  tools/power turbostat: show IRQs per CPU
  tools/power turbostat: make fewer systems calls
  tools/power turbostat: fix compiler warnings
  tools/power turbostat: add --out option for saving output in a file
  tools/power turbostat: re-name "%Busy" field to "Busy%"
  tools/power turbostat: Intel Xeon x200: fix turbo-ratio decoding
  tools/power turbostat: Intel Xeon x200: fix erroneous bclk value
  tools/power turbostat: allow sub-sec intervals
  ACPI / APEI: ERST: Fixed leaked resources in erst_init
  ACPI / APEI: Fix leaked resources
  intel_pstate: Do not skip samples partially
  intel_pstate: Remove freq calculation from intel_pstate_calc_busy()
  intel_pstate: Move intel_pstate_calc_busy() into get_target_pstate_use_performance()
  ...
2016-03-16 14:10:53 -07:00
Arnd Bergmann
cfe02a8a97 cgroup: avoid false positive gcc-6 warning
When all subsystems are disabled, gcc notices that cgroup_subsys_enabled_key
is a zero-length array and that any access to it must be out of bounds:

In file included from ../include/linux/cgroup.h:19:0,
                 from ../kernel/cgroup.c:31:
../kernel/cgroup.c: In function 'cgroup_add_cftypes':
../kernel/cgroup.c:261:53: error: array subscript is above array bounds [-Werror=array-bounds]
  return static_key_enabled(cgroup_subsys_enabled_key[ssid]);
                            ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
../include/linux/jump_label.h:271:40: note: in definition of macro 'static_key_enabled'
  static_key_count((struct static_key *)x) > 0;    \
                                        ^

We should never call the function in this particular case, so this is
not a bug. In order to silence the warning, this adds an explicit check
for the CGROUP_SUBSYS_COUNT==0 case.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-03-16 13:32:23 -07:00
Tejun Heo
2b021cbf3c cgroup: ignore css_sets associated with dead cgroups during migration
Before 2e91fa7f6d ("cgroup: keep zombies associated with their
original cgroups"), all dead tasks were associated with init_css_set.
If a zombie task is requested for migration, while migration prep
operations would still be performed on init_css_set, the actual
migration would ignore zombie tasks.  As init_css_set is always valid,
this worked fine.

However, after 2e91fa7f6d, zombie tasks stay with the css_set it was
associated with at the time of death.  Let's say a task T associated
with cgroup A on hierarchy H-1 and cgroup B on hiearchy H-2.  After T
becomes a zombie, it would still remain associated with A and B.  If A
only contains zombie tasks, it can be removed.  On removal, A gets
marked offline but stays pinned until all zombies are drained.  At
this point, if migration is initiated on T to a cgroup C on hierarchy
H-2, migration path would try to prepare T's css_set for migration and
trigger the following.

 WARNING: CPU: 0 PID: 1576 at kernel/cgroup.c:474 cgroup_get+0x121/0x160()
 CPU: 0 PID: 1576 Comm: bash Not tainted 4.4.0-work+ #289
 ...
 Call Trace:
  [<ffffffff8127e63c>] dump_stack+0x4e/0x82
  [<ffffffff810445e8>] warn_slowpath_common+0x78/0xb0
  [<ffffffff810446d5>] warn_slowpath_null+0x15/0x20
  [<ffffffff810c33e1>] cgroup_get+0x121/0x160
  [<ffffffff810c349b>] link_css_set+0x7b/0x90
  [<ffffffff810c4fbc>] find_css_set+0x3bc/0x5e0
  [<ffffffff810c5269>] cgroup_migrate_prepare_dst+0x89/0x1f0
  [<ffffffff810c7547>] cgroup_attach_task+0x157/0x230
  [<ffffffff810c7a17>] __cgroup_procs_write+0x2b7/0x470
  [<ffffffff810c7bdc>] cgroup_tasks_write+0xc/0x10
  [<ffffffff810c4790>] cgroup_file_write+0x30/0x1b0
  [<ffffffff811c68fc>] kernfs_fop_write+0x13c/0x180
  [<ffffffff81151673>] __vfs_write+0x23/0xe0
  [<ffffffff81152494>] vfs_write+0xa4/0x1a0
  [<ffffffff811532d4>] SyS_write+0x44/0xa0
  [<ffffffff814af2d7>] entry_SYSCALL_64_fastpath+0x12/0x6f

It doesn't make sense to prepare migration for css_sets pointing to
dead cgroups as they are guaranteed to contain only zombies which are
ignored later during migration.  This patch makes cgroup destruction
path mark all affected css_sets as dead and updates the migration path
to ignore them during preparation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 2e91fa7f6d ("cgroup: keep zombies associated with their original cgroups")
Cc: stable@vger.kernel.org # v4.4+
2016-03-16 13:31:46 -07:00
Linus Torvalds
271ecc5253 Merge branch 'akpm' (patches from Andrew)
Merge first patch-bomb from Andrew Morton:

 - some misc things

 - ofs2 updates

 - about half of MM

 - checkpatch updates

 - autofs4 update

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits)
  autofs4: fix string.h include in auto_dev-ioctl.h
  autofs4: use pr_xxx() macros directly for logging
  autofs4: change log print macros to not insert newline
  autofs4: make autofs log prints consistent
  autofs4: fix some white space errors
  autofs4: fix invalid ioctl return in autofs4_root_ioctl_unlocked()
  autofs4: fix coding style line length in autofs4_wait()
  autofs4: fix coding style problem in autofs4_get_set_timeout()
  autofs4: coding style fixes
  autofs: show pipe inode in mount options
  kallsyms: add support for relative offsets in kallsyms address table
  kallsyms: don't overload absolute symbol type for percpu symbols
  x86: kallsyms: disable absolute percpu symbols on !SMP
  checkpatch: fix another left brace warning
  checkpatch: improve UNSPECIFIED_INT test for bare signed/unsigned uses
  checkpatch: warn on bare unsigned or signed declarations without int
  checkpatch: exclude asm volatile from complex macro check
  mm: memcontrol: drop unnecessary lru locking from mem_cgroup_migrate()
  mm: migrate: consolidate mem_cgroup_migrate() calls
  mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous
  ...
2016-03-16 11:51:08 -07:00
Ard Biesheuvel
2213e9a66b kallsyms: add support for relative offsets in kallsyms address table
Similar to how relative extables are implemented, it is possible to emit
the kallsyms table in such a way that it contains offsets relative to
some anchor point in the kernel image rather than absolute addresses.

On 64-bit architectures, it cuts the size of the kallsyms address table
in half, since offsets between kernel symbols can typically be expressed
in 32 bits.  This saves several hundreds of kilobytes of permanent
.rodata on average.  In addition, the kallsyms address table is no
longer subject to dynamic relocation when CONFIG_RELOCATABLE is in
effect, so the relocation work done after decompression now doesn't have
to do relocation updates for all these values.  This saves up to 24
bytes (i.e., the size of a ELF64 RELA relocation table entry) per value,
which easily adds up to a couple of megabytes of uncompressed __init
data on ppc64 or arm64.  Even if these relocation entries typically
compress well, the combined size reduction of 2.8 MB uncompressed for a
ppc64_defconfig build (of which 2.4 MB is __init data) results in a ~500
KB space saving in the compressed image.

Since it is useful for some architectures (like x86) to retain the
ability to emit absolute values as well, this patch also adds support
for capturing both absolute and relative values when
KALLSYMS_ABSOLUTE_PERCPU is in effect, by emitting absolute per-cpu
addresses as positive 32-bit values, and addresses relative to the
lowest encountered relative symbol as negative values, which are
subtracted from the runtime address of this base symbol to produce the
actual address.

Support for the above is enabled by default for all architectures except
IA-64 and Tile-GX, whose symbols are too far apart to capture in this
manner.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 16:55:16 -07:00
Laura Abbott
1414c7f4f7 mm/page_poisoning.c: allow for zero poisoning
By default, page poisoning uses a poison value (0xaa) on free.  If this
is changed to 0, the page is not only sanitized but zeroing on alloc
with __GFP_ZERO can be skipped as well.  The tradeoff is that detecting
corruption from the poisoning is harder to detect.  This feature also
cannot be used with hibernation since pages are not guaranteed to be
zeroed after hibernation.

Credit to Grsecurity/PaX team for inspiring this work

Signed-off-by: Laura Abbott <labbott@fedoraproject.org>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jianyu Zhan <nasa4836@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 16:55:16 -07:00
Andreas Ziegler
07061aab2f mm: fix two typos in comments for to_vmem_altmap()
Commit 4b94ffdc41 ("x86, mm: introduce vmem_altmap to augment
vmemmap_populate()"), introduced the to_vmem_altmap() function.

The comments in this function contain two typos (one misspelling of the
Kconfig option CONFIG_SPARSEMEM_VMEMMAP, and one missing letter 'n'),
let's fix them up.

Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 16:55:16 -07:00
Peter Zijlstra
25528213fe tags: Fix DEFINE_PER_CPU expansions
$ make tags
  GEN     tags
ctags: Warning: drivers/acpi/processor_idle.c:64: null expansion of name pattern "\1"
ctags: Warning: drivers/xen/events/events_2l.c:41: null expansion of name pattern "\1"
ctags: Warning: kernel/locking/lockdep.c:151: null expansion of name pattern "\1"
ctags: Warning: kernel/rcu/rcutorture.c:133: null expansion of name pattern "\1"
ctags: Warning: kernel/rcu/rcutorture.c:135: null expansion of name pattern "\1"
ctags: Warning: kernel/workqueue.c:323: null expansion of name pattern "\1"
ctags: Warning: net/ipv4/syncookies.c:53: null expansion of name pattern "\1"
ctags: Warning: net/ipv6/syncookies.c:44: null expansion of name pattern "\1"
ctags: Warning: net/rds/page.c:45: null expansion of name pattern "\1"

Which are all the result of the DEFINE_PER_CPU pattern:

  scripts/tags.sh:200:	'/\<DEFINE_PER_CPU([^,]*, *\([[:alnum:]_]*\)/\1/v/'
  scripts/tags.sh:201:	'/\<DEFINE_PER_CPU_SHARED_ALIGNED([^,]*, *\([[:alnum:]_]*\)/\1/v/'

The below cures them. All except the workqueue one are within reasonable
distance of the 80 char limit. TJ do you have any preference on how to
fix the wq one, or shall we just not care its too long?

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 16:55:16 -07:00
Linus Torvalds
710d60cbf1 Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull cpu hotplug updates from Thomas Gleixner:
 "This is the first part of the ongoing cpu hotplug rework:

   - Initial implementation of the state machine

   - Runs all online and prepare down callbacks on the plugged cpu and
     not on some random processor

   - Replaces busy loop waiting with completions

   - Adds tracepoints so the states can be followed"

More detailed commentary on this work from an earlier email:
 "What's wrong with the current cpu hotplug infrastructure?

   - Asymmetry

     The hotplug notifier mechanism is asymmetric versus the bringup and
     teardown.  This is mostly caused by the notifier mechanism.

   - Largely undocumented dependencies

     While some notifiers use explicitely defined notifier priorities,
     we have quite some notifiers which use numerical priorities to
     express dependencies without any documentation why.

   - Control processor driven

     Most of the bringup/teardown of a cpu is driven by a control
     processor.  While it is understandable, that preperatory steps,
     like idle thread creation, memory allocation for and initialization
     of essential facilities needs to be done before a cpu can boot,
     there is no reason why everything else must run on a control
     processor.  Before this patch series, bringup looks like this:

       Control CPU                     Booting CPU

       do preparatory steps
       kick cpu into life

                                       do low level init

       sync with booting cpu           sync with control cpu

       bring the rest up

   - All or nothing approach

     There is no way to do partial bringups.  That's something which is
     really desired because we waste e.g.  at boot substantial amount of
     time just busy waiting that the cpu comes to life.  That's stupid
     as we could very well do preparatory steps and the initial IPI for
     other cpus and then go back and do the necessary low level
     synchronization with the freshly booted cpu.

   - Minimal debuggability

     Due to the notifier based design, it's impossible to switch between
     two stages of the bringup/teardown back and forth in order to test
     the correctness.  So in many hotplug notifiers the cancel
     mechanisms are either not existant or completely untested.

   - Notifier [un]registering is tedious

     To [un]register notifiers we need to protect against hotplug at
     every callsite.  There is no mechanism that bringup/teardown
     callbacks are issued on the online cpus, so every caller needs to
     do it itself.  That also includes error rollback.

  What's the new design?

     The base of the new design is a symmetric state machine, where both
     the control processor and the booting/dying cpu execute a well
     defined set of states.  Each state is symmetric in the end, except
     for some well defined exceptions, and the bringup/teardown can be
     stopped and reversed at almost all states.

     So the bringup of a cpu will look like this in the future:

       Control CPU                     Booting CPU

       do preparatory steps
       kick cpu into life

                                       do low level init

       sync with booting cpu           sync with control cpu

                                       bring itself up

     The synchronization step does not require the control cpu to wait.
     That mechanism can be done asynchronously via a worker or some
     other mechanism.

     The teardown can be made very similar, so that the dying cpu cleans
     up and brings itself down.  Cleanups which need to be done after
     the cpu is gone, can be scheduled asynchronously as well.

  There is a long way to this, as we need to refactor the notion when a
  cpu is available.  Today we set the cpu online right after it comes
  out of the low level bringup, which is not really correct.

  The proper mechanism is to set it to available, i.e. cpu local
  threads, like softirqd, hotplug thread etc. can be scheduled on that
  cpu, and once it finished all booting steps, it's set to online, so
  general workloads can be scheduled on it.  The reverse happens on
  teardown.  First thing to do is to forbid scheduling of general
  workloads, then teardown all the per cpu resources and finally shut it
  off completely.

  This patch series implements the basic infrastructure for this at the
  core level.  This includes the following:

   - Basic state machine implementation with well defined states, so
     ordering and prioritization can be expressed.

   - Interfaces to [un]register state callbacks

     This invokes the bringup/teardown callback on all online cpus with
     the proper protection in place and [un]installs the callbacks in
     the state machine array.

     For callbacks which have no particular ordering requirement we have
     a dynamic state space, so that drivers don't have to register an
     explicit hotplug state.

     If a callback fails, the code automatically does a rollback to the
     previous state.

   - Sysfs interface to drive the state machine to a particular step.

     This is only partially functional today.  Full functionality and
     therefor testability will be achieved once we converted all
     existing hotplug notifiers over to the new scheme.

   - Run all CPU_ONLINE/DOWN_PREPARE notifiers on the booting/dying
     processor:

       Control CPU                     Booting CPU

       do preparatory steps
       kick cpu into life

                                       do low level init

       sync with booting cpu           sync with control cpu
       wait for boot
                                       bring itself up

                                       Signal completion to control cpu

     In a previous step of this work we've done a full tree mechanical
     conversion of all hotplug notifiers to the new scheme.  The balance
     is a net removal of about 4000 lines of code.

     This is not included in this series, as we decided to take a
     different approach.  Instead of mechanically converting everything
     over, we will do a proper overhaul of the usage sites one by one so
     they nicely fit into the symmetric callback scheme.

     I decided to do that after I looked at the ugliness of some of the
     converted sites and figured out that their hotplug mechanism is
     completely buggered anyway.  So there is no point to do a
     mechanical conversion first as we need to go through the usage
     sites one by one again in order to achieve a full symmetric and
     testable behaviour"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  cpu/hotplug: Document states better
  cpu/hotplug: Fix smpboot thread ordering
  cpu/hotplug: Remove redundant state check
  cpu/hotplug: Plug death reporting race
  rcu: Make CPU_DYING_IDLE an explicit call
  cpu/hotplug: Make wait for dead cpu completion based
  cpu/hotplug: Let upcoming cpu bring itself fully up
  arch/hotplug: Call into idle with a proper state
  cpu/hotplug: Move online calls to hotplugged cpu
  cpu/hotplug: Create hotplug threads
  cpu/hotplug: Split out the state walk into functions
  cpu/hotplug: Unpark smpboot threads from the state machine
  cpu/hotplug: Move scheduler cpu_online notifier to hotplug core
  cpu/hotplug: Implement setup/removal interface
  cpu/hotplug: Make target state writeable
  cpu/hotplug: Add sysfs state interface
  cpu/hotplug: Hand in target state to _cpu_up/down
  cpu/hotplug: Convert the hotplugged cpu work to a state machine
  cpu/hotplug: Convert to a state machine for the control processor
  cpu/hotplug: Add tracepoints
  ...
2016-03-15 13:50:29 -07:00
Linus Torvalds
df2e37c814 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "The 4.6 pile of irq updates contains:

   - Support for IPI irqdomains to support proper integration of IPIs to
     and from coprocessors.  The first user of this new facility is
     MIPS.  The relevant MIPS patches come with the core to avoid merge
     ordering issues and have been acked by Ralf.

   - A new command line option to set the default interrupt affinity
     mask at boot time.

   - Support for some more new ARM and MIPS interrupt controllers:
     tango, alpine-msix and bcm6345-l1

   - Two small cleanups for x86/apic which we merged into irq/core to
     avoid yet another branch in x86 with two tiny commits.

   - The usual set of updates, cleanups in drivers/irqchip.  Mostly in
     the area of ARM-GIC, arada-37-xp and atmel chips.  Nothing
     outstanding here"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits)
  irqchip/irq-alpine-msi: Release the correct domain on error
  irqchip/mxs: Fix error check of of_io_request_and_map()
  irqchip/sunxi-nmi: Fix error check of of_io_request_and_map()
  genirq: Export IRQ functions for module use
  irqchip/gic/realview: Support more RealView DCC variants
  Documentation/bindings: Document the Alpine MSIX driver
  irqchip: Add the Alpine MSIX interrupt controller
  irqchip/gic-v3: Always return IRQ_SET_MASK_OK_DONE in gic_set_affinity
  irqchip/gic-v3-its: Mark its_init() and its children as __init
  irqchip/gic-v3: Remove gic_root_node variable from the ITS code
  irqchip/gic-v3: ACPI: Add redistributor support via GICC structures
  irqchip/gic-v3: Add ACPI support for GICv3/4 initialization
  irqchip/gic-v3: Refactor gic_of_init() for GICv3 driver
  x86/apic: Deinline _flat_send_IPI_mask, save ~150 bytes
  x86/apic: Deinline __default_send_IPI_*, save ~200 bytes
  dt-bindings: interrupt-controller: Add SoC-specific compatible string to Marvell ODMI
  irqchip/mips-gic: Add new DT property to reserve IPIs
  MIPS: Delete smp-gic.c
  MIPS: Make smp CMP, CPS and MT use the new generic IPI functions
  MIPS: Add generic SMP IPI support
  ...
2016-03-15 12:48:48 -07:00
Linus Torvalds
8a284c062e Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "The timer department delivers this time:

   - Support for cross clock domain timestamps in the core code plus a
     first user.  That allows more precise timestamping for PTP and
     later for audio and other peripherals.

     The ptp/e1000e patches have been acked by the relevant maintainers
     and are carried in the timer tree to avoid merge ordering issues.

   - Support for unregistering the current clocksource watchdog.  That
     lifts a limitation for switching clocksources which has been there
     from day 1

   - The usual pile of fixes and updates to the core and the drivers.
     Nothing outstanding and exciting"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  time/timekeeping: Work around false positive GCC warning
  e1000e: Adds hardware supported cross timestamp on e1000e nic
  ptp: Add PTP_SYS_OFFSET_PRECISE for driver crosstimestamping
  x86/tsc: Always Running Timer (ART) correlated clocksource
  hrtimer: Revert CLOCK_MONOTONIC_RAW support
  time: Add history to cross timestamp interface supporting slower devices
  time: Add driver cross timestamp interface for higher precision time synchronization
  time: Remove duplicated code in ktime_get_raw_and_real()
  time: Add timekeeping snapshot code capturing system time and counter
  time: Add cycles to nanoseconds translation
  jiffies: Use CLOCKSOURCE_MASK instead of constant
  clocksource: Introduce clocksource_freq2mult()
  clockevents/drivers/exynos_mct: Implement ->set_state_oneshot_stopped()
  clockevents/drivers/arm_global_timer: Implement ->set_state_oneshot_stopped()
  clockevents/drivers/arm_arch_timer: Implement ->set_state_oneshot_stopped()
  clocksource/drivers/arm_global_timer: Register delay timer
  clocksource/drivers/lpc32xx: Support timer-based ARM delay
  clocksource/drivers/lpc32xx: Support periodic mode
  clocksource/drivers/lpc32xx: Don't use the prescaler counter for clockevents
  clocksource/drivers/rockchip: Add err handle for rk_timer_init
  ...
2016-03-15 12:13:56 -07:00
Linus Torvalds
208de21477 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 changes in this cycle were:

   - Miscellaneous fixes, cleanups, restructuring.

   - RCU torture-test updates"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rcu: Export rcu_gp_is_normal()
  rcu: Remove rcu_user_hooks_switch
  rcu: Catch up rcu_report_qs_rdp() comment with reality
  rcu: Document unique-name limitation for DEFINE_STATIC_SRCU()
  rcu: Make rcu/tiny_plugin.h explicitly non-modular
  irq: Privatize irq_common_data::state_use_accessors
  RCU: Privatize rcu_node::lock
  sparse: Add __private to privatize members of structs
  rcu: Remove useless rcu_data_p when !PREEMPT_RCU
  rcutorture: Correct no-expedite console messages
  rcu: Set rdp->gpwrap when CPU is idle
  rcu: Stop treating in-kernel CPU-bound workloads as errors
  rcu: Update rcu_report_qs_rsp() comment
  rcu: Assign false instead of 0 for ->core_needs_qs
  rcutorture: Check for self-detected stalls
  rcutorture: Don't keep empty console.log.diags files
  rcutorture: Add checks for rcutorture writer starvation
2016-03-15 11:38:05 -07:00
Linus Torvalds
ba33ea811e Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:
 "This is another big update. Main changes are:

   - lots of x86 system call (and other traps/exceptions) entry code
     enhancements.  In particular the complex parts of the 64-bit entry
     code have been migrated to C code as well, and a number of dusty
     corners have been refreshed.  (Andy Lutomirski)

   - vDSO special mapping robustification and general cleanups (Andy
     Lutomirski)

   - cpufeature refactoring, cleanups and speedups (Borislav Petkov)

   - lots of other changes ..."

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
  x86/cpufeature: Enable new AVX-512 features
  x86/entry/traps: Show unhandled signal for i386 in do_trap()
  x86/entry: Call enter_from_user_mode() with IRQs off
  x86/entry/32: Change INT80 to be an interrupt gate
  x86/entry: Improve system call entry comments
  x86/entry: Remove TIF_SINGLESTEP entry work
  x86/entry/32: Add and check a stack canary for the SYSENTER stack
  x86/entry/32: Simplify and fix up the SYSENTER stack #DB/NMI fixup
  x86/entry: Only allocate space for tss_struct::SYSENTER_stack if needed
  x86/entry: Vastly simplify SYSENTER TF (single-step) handling
  x86/entry/traps: Clear DR6 early in do_debug() and improve the comment
  x86/entry/traps: Clear TIF_BLOCKSTEP on all debug exceptions
  x86/entry/32: Restore FLAGS on SYSEXIT
  x86/entry/32: Filter NT and speed up AC filtering in SYSENTER
  x86/entry/compat: In SYSENTER, sink AC clearing below the existing FLAGS test
  selftests/x86: In syscall_nt, test NT|TF as well
  x86/asm-offsets: Remove PARAVIRT_enabled
  x86/entry/32: Introduce and use X86_BUG_ESPFIX instead of paravirt_enabled
  uprobes: __create_xol_area() must nullify xol_mapping.fault
  x86/cpufeature: Create a new synthetic cpu capability for machine check recovery
  ...
2016-03-15 09:32:27 -07:00
Ingo Molnar
670191572e Merge commit 'torture.2015.02.23a' into core/rcu
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-15 09:01:17 +01:00
Ingo Molnar
8bc6782fe2 Merge commit 'fixes.2015.02.23a' into core/rcu
Conflicts:
	kernel/rcu/tree.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-15 09:01:06 +01:00
Linus Torvalds
e23604edac Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull NOHZ updates from Ingo Molnar:
 "NOHZ enhancements, by Frederic Weisbecker, which reorganizes/refactors
  the NOHZ 'can the tick be stopped?' infrastructure and related code to
  be data driven, and harmonizes the naming and handling of all the
  various properties"

[ This makes the ugly "fetch_or()" macro that the scheduler used
  internally a new generic helper, and does a bad job at it.

  I'm pulling it, but I've asked Ingo and Frederic to get this
  fixed up ]

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched-clock: Migrate to use new tick dependency mask model
  posix-cpu-timers: Migrate to use new tick dependency mask model
  sched: Migrate sched to use new tick dependency mask model
  sched: Account rr tasks
  perf: Migrate perf to use new tick dependency mask model
  nohz: Use enum code for tick stop failure tracing message
  nohz: New tick dependency mask
  nohz: Implement wide kick on top of irq work
  atomic: Export fetch_or()
2016-03-14 19:44:38 -07:00
Linus Torvalds
d4e796152a Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle are:

   - Make schedstats a runtime tunable (disabled by default) and
     optimize it via static keys.

     As most distributions enable CONFIG_SCHEDSTATS=y due to its
     instrumentation value, this is a nice performance enhancement.
     (Mel Gorman)

   - Implement 'simple waitqueues' (swait): these are just pure
     waitqueues without any of the more complex features of full-blown
     waitqueues (callbacks, wake flags, wake keys, etc.).  Simple
     waitqueues have less memory overhead and are faster.

     Use simple waitqueues in the RCU code (in 4 different places) and
     for handling KVM vCPU wakeups.

     (Peter Zijlstra, Daniel Wagner, Thomas Gleixner, Paul Gortmaker,
     Marcelo Tosatti)

   - sched/numa enhancements (Rik van Riel)

   - NOHZ performance enhancements (Rik van Riel)

   - Various sched/deadline enhancements (Steven Rostedt)

   - Various fixes (Peter Zijlstra)

   - ... and a number of other fixes, cleanups and smaller enhancements"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits)
  sched/cputime: Fix steal_account_process_tick() to always return jiffies
  sched/deadline: Remove dl_new from struct sched_dl_entity
  Revert "kbuild: Add option to turn incompatible pointer check into error"
  sched/deadline: Remove superfluous call to switched_to_dl()
  sched/debug: Fix preempt_disable_ip recording for preempt_disable()
  sched, time: Switch VIRT_CPU_ACCOUNTING_GEN to jiffy granularity
  time, acct: Drop irq save & restore from __acct_update_integrals()
  acct, time: Change indentation in __acct_update_integrals()
  sched, time: Remove non-power-of-two divides from __acct_update_integrals()
  sched/rt: Kick RT bandwidth timer immediately on start up
  sched/debug: Add deadline scheduler bandwidth ratio to /proc/sched_debug
  sched/debug: Move sched_domain_sysctl to debug.c
  sched/debug: Move the /sys/kernel/debug/sched_features file setup into debug.c
  sched/rt: Fix PI handling vs. sched_setscheduler()
  sched/core: Remove duplicated sched_group_set_shares() prototype
  sched/fair: Consolidate nohz CPU load update code
  sched/fair: Avoid using decay_load_missed() with a negative value
  sched/deadline: Always calculate end of period on sched_yield()
  sched/cgroup: Fix cgroup entity load tracking tear-down
  rcu: Use simple wait queues where possible in rcutree
  ...
2016-03-14 19:14:06 -07:00
Linus Torvalds
e71c2c1eeb Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Main kernel side changes:

   - Big reorganization of the x86 perf support code.  The old code grew
     organically deep inside arch/x86/kernel/cpu/perf* and its naming
     became somewhat messy.

     The new location is under arch/x86/events/, using the following
     cleaner hierarchy of source code files:

       perf/x86: Move perf_event.c .................. => x86/events/core.c
       perf/x86: Move perf_event_amd.c .............. => x86/events/amd/core.c
       perf/x86: Move perf_event_amd_ibs.c .......... => x86/events/amd/ibs.c
       perf/x86: Move perf_event_amd_iommu.[ch] ..... => x86/events/amd/iommu.[ch]
       perf/x86: Move perf_event_amd_uncore.c ....... => x86/events/amd/uncore.c
       perf/x86: Move perf_event_intel_bts.c ........ => x86/events/intel/bts.c
       perf/x86: Move perf_event_intel.c ............ => x86/events/intel/core.c
       perf/x86: Move perf_event_intel_cqm.c ........ => x86/events/intel/cqm.c
       perf/x86: Move perf_event_intel_cstate.c ..... => x86/events/intel/cstate.c
       perf/x86: Move perf_event_intel_ds.c ......... => x86/events/intel/ds.c
       perf/x86: Move perf_event_intel_lbr.c ........ => x86/events/intel/lbr.c
       perf/x86: Move perf_event_intel_pt.[ch] ...... => x86/events/intel/pt.[ch]
       perf/x86: Move perf_event_intel_rapl.c ....... => x86/events/intel/rapl.c
       perf/x86: Move perf_event_intel_uncore.[ch] .. => x86/events/intel/uncore.[ch]
       perf/x86: Move perf_event_intel_uncore_nhmex.c => x86/events/intel/uncore_nmhex.c
       perf/x86: Move perf_event_intel_uncore_snb.c   => x86/events/intel/uncore_snb.c
       perf/x86: Move perf_event_intel_uncore_snbep.c => x86/events/intel/uncore_snbep.c
       perf/x86: Move perf_event_knc.c .............. => x86/events/intel/knc.c
       perf/x86: Move perf_event_p4.c ............... => x86/events/intel/p4.c
       perf/x86: Move perf_event_p6.c ............... => x86/events/intel/p6.c
       perf/x86: Move perf_event_msr.c .............. => x86/events/msr.c

     (Borislav Petkov)

   - Update various x86 PMU constraint and hw support details (Stephane
     Eranian)

   - Optimize kprobes for BPF execution (Martin KaFai Lau)

   - Rewrite, refactor and fix the Intel uncore PMU driver code (Thomas
     Gleixner)

   - Rewrite, refactor and fix the Intel RAPL PMU code (Thomas Gleixner)

   - Various fixes and smaller cleanups.

  There are lots of perf tooling updates as well.  A few highlights:

  perf report/top:

     - Hierarchy histogram mode for 'perf top' and 'perf report',
       showing multiple levels, one per --sort entry: (Namhyung Kim)

       On a mostly idle system:

         # perf top --hierarchy -s comm,dso

       Then expand some levels and use 'P' to take a snapshot:

         # cat perf.hist.0
         -  92.32%         perf
               58.20%         perf
               22.29%         libc-2.22.so
                5.97%         [kernel]
                4.18%         libelf-0.165.so
                1.69%         [unknown]
         -   4.71%         qemu-system-x86
                3.10%         [kernel]
                1.60%         qemu-system-x86_64 (deleted)
         +   2.97%         swapper
         #

     - Add 'L' hotkey to dynamicly set the percent threshold for
       histogram entries and callchains, i.e.  dynamicly do what the
       --percent-limit command line option to 'top' and 'report' does.
       (Namhyung Kim)

  perf mem:

     - Allow specifying events via -e in 'perf mem record', also listing
       what events can be specified via 'perf mem record -e list' (Jiri
       Olsa)

  perf record:

     - Add 'perf record' --all-user/--all-kernel options, so that one
       can tell that all the events in the command line should be
       restricted to the user or kernel levels (Jiri Olsa), i.e.:

         perf record -e cycles:u,instructions:u

       is equivalent to:

         perf record --all-user -e cycles,instructions

     - Make 'perf record' collect CPU cache info in the perf.data file header:

         $ perf record usleep 1
         [ perf record: Woken up 1 times to write data ]
         [ perf record: Captured and wrote 0.017 MB perf.data (7 samples) ]
         $ perf report --header-only -I | tail -10 | head -8
         # CPU cache info:
         #  L1 Data                 32K [0-1]
         #  L1 Instruction          32K [0-1]
         #  L1 Data                 32K [2-3]
         #  L1 Instruction          32K [2-3]
         #  L2 Unified             256K [0-1]
         #  L2 Unified             256K [2-3]
         #  L3 Unified            4096K [0-3]

       Will be used in 'perf c2c' and eventually in 'perf diff' to
       allow, for instance running the same workload in multiple
       machines and then when using 'diff' show the hardware difference.
       (Jiri Olsa)

     - Improved support for Java, using the JVMTI agent library to do
       jitdumps that then will be inserted in synthesized
       PERF_RECORD_MMAP2 events via 'perf inject' pointed to synthesized
       ELF files stored in ~/.debug and keyed with build-ids, to allow
       symbol resolution and even annotation with source line info, see
       the changeset comments to see how to use it (Stephane Eranian)

  perf script/trace:

     - Decode data_src values (e.g.  perf.data files generated by 'perf
       mem record') in 'perf script': (Jiri Olsa)

         # perf script
           perf 693 [1] 4.088652: 1 cpu/mem-loads,ldlat=30/P: ffff88007d0b0f40 68100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK No <SNIP>
                                                                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     - Improve support to 'data_src', 'weight' and 'addr' fields in
       'perf script' (Jiri Olsa)

     - Handle empty print fmts in 'perf script -s' i.e. when running
       python or perl scripts (Taeung Song)

  perf stat:

     - 'perf stat' now shows shadow metrics (insn per cycle, etc) in
       interval mode too.  E.g:

         # perf stat -I 1000 -e instructions,cycles sleep 1
         #         time   counts unit events
            1.000215928  519,620      instructions     #  0.69 insn per cycle
            1.000215928  752,003      cycles
         <SNIP>

     - Port 'perf kvm stat' to PowerPC (Hemant Kumar)

     - Implement CSV metrics output in 'perf stat' (Andi Kleen)

  perf BPF support:

     - Support converting data from bpf events in 'perf data' (Wang Nan)

     - Print bpf-output events in 'perf script': (Wang Nan).

         # perf record -e bpf-output/no-inherit,name=evt/ -e ./test_bpf_output_3.c/map:channel.event=evt/ usleep 1000
         # perf script
            usleep  4882 21384.532523:   evt:  ffffffff810e97d1 sys_nanosleep ([kernel.kallsyms])
             BPF output: 0000: 52 61 69 73 65 20 61 20  Raise a
                         0008: 42 50 46 20 65 76 65 6e  BPF even
                         0010: 74 21 00 00              t!..
             BPF string: "Raise a BPF event!"
         #

     - Add API to set values of map entries in a BPF object, be it
       individual map slots or ranges (Wang Nan)

     - Introduce support for the 'bpf-output' event (Wang Nan)

     - Add glue to read perf events in a BPF program (Wang Nan)

     - Improve support for bpf-output events in 'perf trace' (Wang Nan)

  ... and tons of other changes as well - see the shortlog and git log
  for details!"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (342 commits)
  perf stat: Add --metric-only support for -A
  perf stat: Implement --metric-only mode
  perf stat: Document CSV format in manpage
  perf hists browser: Check sort keys before hot key actions
  perf hists browser: Allow thread filtering for comm sort key
  perf tools: Add sort__has_comm variable
  perf tools: Recalc total periods using top-level entries in hierarchy
  perf tools: Remove nr_sort_keys field
  perf hists browser: Cleanup hist_browser__fprintf_hierarchy_entry()
  perf tools: Remove hist_entry->fmt field
  perf tools: Fix command line filters in hierarchy mode
  perf tools: Add more sort entry check functions
  perf tools: Fix hist_entry__filter() for hierarchy
  perf jitdump: Build only on supported archs
  tools lib traceevent: Add '~' operation within arg_num_eval()
  perf tools: Omit unnecessary cast in perf_pmu__parse_scale
  perf tools: Pass perf_hpp_list all the way through setup_sort_list
  perf tools: Fix perf script python database export crash
  perf jitdump: DWARF is also needed
  perf bench mem: Prepare the x86-64 build for upstream memcpy_mcsafe() changes
  ...
2016-03-14 17:58:53 -07:00
Linus Torvalds
d09e356ad0 Merge branch 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull read-only kernel memory updates from Ingo Molnar:
 "This tree adds two (security related) enhancements to the kernel's
  handling of read-only kernel memory:

   - extend read-only kernel memory to a new class of formerly writable
     kernel data: 'post-init read-only memory' via the __ro_after_init
     attribute, and mark the ARM and x86 vDSO as such read-only memory.

     This kind of attribute can be used for data that requires a once
     per bootup initialization sequence, but is otherwise never modified
     after that point.

     This feature was based on the work by PaX Team and Brad Spengler.

     (by Kees Cook, the ARM vDSO bits by David Brown.)

   - make CONFIG_DEBUG_RODATA always enabled on x86 and remove the
     Kconfig option.  This simplifies the kernel and also signals that
     read-only memory is the default model and a first-class citizen.
     (Kees Cook)"

* 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ARM/vdso: Mark the vDSO code read-only after init
  x86/vdso: Mark the vDSO code read-only after init
  lkdtm: Verify that '__ro_after_init' works correctly
  arch: Introduce post-init read-only memory
  x86/mm: Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option
  mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings
  asm-generic: Consolidate mark_rodata_ro()
2016-03-14 16:58:50 -07:00
Linus Torvalds
fbed0bc091 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking changes from Ingo Molnar:
 "Various updates:

   - Futex scalability improvements: remove page lock use for shared
     futex get_futex_key(), which speeds up 'perf bench futex hash'
     benchmarks by over 40% on a 60-core Westmere.  This makes anon-mem
     shared futexes perform close to private futexes.  (Mel Gorman)

   - lockdep hash collision detection and fix (Alfredo Alvarez
     Fernandez)

   - lockdep testing enhancements (Alfredo Alvarez Fernandez)

   - robustify lockdep init by using hlists (Andrew Morton, Andrey
     Ryabinin)

   - mutex and csd_lock micro-optimizations (Davidlohr Bueso)

   - small x86 barriers tweaks (Michael S Tsirkin)

   - qspinlock updates (Waiman Long)"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  locking/csd_lock: Use smp_cond_acquire() in csd_lock_wait()
  locking/csd_lock: Explicitly inline csd_lock*() helpers
  futex: Replace barrier() in unqueue_me() with READ_ONCE()
  locking/lockdep: Detect chain_key collisions
  locking/lockdep: Prevent chain_key collisions
  tools/lib/lockdep: Fix link creation warning
  tools/lib/lockdep: Add tests for AA and ABBA locking
  tools/lib/lockdep: Add userspace version of READ_ONCE()
  tools/lib/lockdep: Fix the build on recent kernels
  locking/qspinlock: Move __ARCH_SPIN_LOCK_UNLOCKED to qspinlock_types.h
  locking/mutex: Allow next waiter lockless wakeup
  locking/pvqspinlock: Enable slowpath locking count tracking
  locking/qspinlock: Use smp_cond_acquire() in pending code
  locking/pvqspinlock: Move lock stealing count tracking code into pv_queued_spin_steal_lock()
  locking/mcs: Fix mcs_spin_lock() ordering
  futex: Remove requirement for lock_page() in get_futex_key()
  futex: Rename barrier references in ordering guarantees
  locking/atomics: Update comment about READ_ONCE() and structures
  locking/lockdep: Eliminate lockdep_init()
  locking/lockdep: Convert hash tables to hlists
  ...
2016-03-14 15:50:44 -07:00