perf tools: Fix split_kallsyms_for_kcore() for trampoline symbols

Kallsyms symbols do not have a size, so the size becomes the distance to
the next symbol.

Consequently the recently added trampoline symbols end up with large
sizes because the trampolines are some distance from one another and the
main kernel map.

However, symbols that end outside their map can disrupt the symbol tree
because, after mapping, it can appear incorrectly that they overlap
other symbols.

Add logic to truncate symbol size to the end of the corresponding map.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: stable@vger.kernel.org
Fixes: d83212d5dd67 ("kallsyms, x86: Export addresses of PTI entry trampolines")
Link: http://lkml.kernel.org/r/20190109091835.5570-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf vendor events intel: Fix Load_Miss_Real_Latency on CLX

Fix incorrect event names for the Load_Miss_Real_Latency metric for
Cascadelake server in the same manner as commit 91b2b97025 for SKL/SKX.

Signed-off-by: William Cohen <wcohen@redhat.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190129170536.22510-1-wcohen@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf cs-etm: Set sample flags for exception return packet

When return from exception, we need to distinguish if it's system call
return or for other type exceptions for setting sample flags.  Due to
the exception return packet doesn't contain exception number, so we
cannot decide sample flags based on exception number.

On the other hand, the exception return packet is followed by an
instruction range packet; this range packet deliveries the start address
after exception handling, we can check if it is a SVC instruction just
before the start address.  If there has one SVC instruction is found
ahead the return address, this means it's an exception return for system
call; otherwise it is an normal return for other exceptions.

This patch is to set sample flags for exception return packet, firstly
it simply set sample flags as PERF_IP_FLAG_INTERRUPT for all exception
returns since at this point it doesn't know what's exactly the exception
type.  We will defer to decide if it's an exception return for system
call when the next instruction range packet comes, it checks if there
has one SVC instruction prior to the start address and if so we will
change sample flags to PERF_IP_FLAG_SYSCALLRET for system call return.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190129122842.32041-9-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf cs-etm: Set sample flags for exception packet

The exception taken and returning are typical flow for instruction jump
but it needs to be handled with exception packets. This patch is to set
sample flags for exception packet.

Since the exception packet contains the exception number, according to
the exception number this patch makes decision for belonging to which
exception types.

The decoder have defined different exception number for ETMv3 and ETMv4
separately, hence this patch needs firstly decide the ETM version by
using the metadata magic number, and this patch adds helper function
cs_etm__get_magic() for easily getting magic number.

Based on different ETM version, the exception packet contains the
exception number, according to the exception number this patch makes
decision for the exception belonging to which exception types.

In this patch, it introduces helper function cs_etm__is_svc_instr(); for
ETMv4 CS_ETMV4_EXC_CALL covers SVC, SMC and HVC cases in the single
exception number, thus need to use cs_etm__is_svc_instr() to decide an
exception taken for system call.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Robert Walker <robert.walker@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190129122842.32041-8-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf cs-etm: Add traceID in packet

Add traceID in packet, thus we can use traceID to retrieve metadata
pointer from traceID-metadata tuple.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190129122842.32041-7-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf cs-etm: Change tuple from traceID-CPU# to traceID-metadata

If packet processing wants to know the packet is bound with which ETM
version, it needs to access metadata to decide that based on metadata
magic number; but we cannot simply to use CPU logic ID number as index
to access metadata sequential array, especially when system have
hotplugged off CPUs, the metadata array are only allocated for online
CPUs but not offline CPUs, so the CPU logic number doesn't match with
its index in the array.

This patch is to change tuple from traceID-CPU# to traceID-metadata,
thus it can use the tuple to retrieve metadata pointer according to
traceID.

For safe accessing metadata fields, this patch provides helper function
cs_etm__get_cpu() which is used to return CPU number according to
traceID; cs_etm_decoder__buffer_packet() is the first consumer for this
helper function.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190129122842.32041-6-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf cs-etm: Add exception number in exception packet

When an exception packet comes, it contains the information for
exception number; the exception number indicates the exception types, so
from it we can know if the exception is taken for interrupt, system call
or other traps, etc.

This patch simply adds a field in cs_etm_packet struct, it records
exception number for exception packet that will then be used to properly
identify exception types to the perf synthesize mechanic.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190129122842.32041-5-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf cs-etm: Set sample flags for trace discontinuity

In the middle of trace stream, it might be interrupted thus the trace
data is not continuous, the trace stream firstly is ended for previous
trace block and restarted for next block.

To display related information for showing trace is restarted, this
patch set sample flags for trace discontinuity:

- If one discontinuity packet is coming, append flag
  PERF_IP_FLAG_TRACE_END to the previous packet to indicate the trace
  has been ended;
- If one instruction packet is following discontinuity packet, this
  instruction packet is the first one packet to restarting trace.  So
  set flag PERF_IP_FLAG_TRACE_START to discontinuity packet, this flag
  will be used to generate sample when connect with the sequential
  instruction packet.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190129122842.32041-4-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf cs-etm: Set sample flags for instruction range packet

The perf sample data contains flags to indicate the hardware trace data
is belonging to which type branch instruction, thus this can be used to
print out the human readable string.  Arm CoreSight ETM sample data is
missed to set flags and it is always set to zeros, this results in perf
tool skips to print string for instruction types.

This patch is to set branch instruction flags for instruction range
packet.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190129122842.32041-3-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf cs-etm: Add last instruction information in packet

Decoder provides last instruction related information, these information
can be used for trace analysis; specifically we can get to know what
kind of branch instruction has been executed, mainly the information are
contained in three element fields:

  last_i_type: this is significant type for waypoint calculation, it
  indicates the last instruction is one of immediate branch instruction,
  indirect branch instruction, instruction barrier (ISB), or data
  barrier (DSB/DMB).

  last_i_subtype: this is used for instruction sub type, it can be
  branch with link, ARMv8 return instruction, ARMv8 eret instruction
  (return from exception), or ARMv7 instruction which could imply
  return (e.g. MOV PC, LR; POP { ,PC}).

  last_instr_cond: it indicates if the last instruction was conditional.

But these three fields are not saved into cs_etm_packet struct, thus
cs-etm layer don't know related information and cannot generate sample
flags for branch instructions.

This patch add corresponding three new fields in cs_etm_packet struct
and save related value into the packet structure, it is preparation for
supporting sample flags.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190129122842.32041-2-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Add documentation for BPF event selection

Add documentation for how to pass a BPF program as a perf event.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190201134651.12373-1-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf report: Move symbol annotation to the resort phase

Currently we make the annotation for the IPC column during the entry
display, already outside of the progress bar scope, so it appears like
'perf report' is stuck.

Move the annotation retrieval to the resort phase, so that all the data
are ready for display.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190204141808.23031-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf evsel: Add output_resort_cb method

Add perf_evsel__output_resort_cb() so we have an interface with a
callback for each hist entry. It will be used in the following patch.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190204141808.23031-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf hists: Add argument to hists__resort_cb_t callback

Add argument to hists__resort_cb_t so that we can pass data from upper
layers to the callback function. It will be used in the following
patches.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190204141808.23031-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf clang: Do not use 'return std::move(something)'

It prevents copy elision, generating this warning when building with
fedora:rawhide's clang:

  clang version 7.0.1 (Fedora 7.0.1-2.fc30)
  Target: x86_64-unknown-linux-gnu
  Thread model: posix
  InstalledDir: /usr/bin
  Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-redhat-linux/9
  Found candidate GCC installation: /usr/lib/gcc/x86_64-redhat-linux/9
  Selected GCC installation: /usr/bin/../lib/gcc/x86_64-redhat-linux/9
  Candidate multilib: .;@m64
  Candidate multilib: 32;@m32
  Selected multilib: .;@m64

  $ make -C tools/perf CC=clang LIBCLANGLLVM=1
  <SNIP>
  util/c++/clang.cpp: In function 'std::unique_ptr<llvm::SmallVectorImpl<char> > perf::getBPFObjectFromModule(llvm::Module*)':
  util/c++/clang.cpp:163:18: error: moving a local object in a return statement prevents copy elision [-Werror=pessimizing-move]
    163 |  return std::move(Buffer);
        |         ~~~~~~~~~^~~~~~~~
  util/c++/clang.cpp:163:18: note: remove 'std::move' call
  cc1plus: all warnings being treated as errors
  <SNIP>

References:

  http://www.cplusplus.com/forum/general/186411/#msg908572
  https://en.cppreference.com/w/cpp/language/return#Notes
  https://en.cppreference.com/w/cpp/language/copy_elision

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-lehqf5x5q96l0o8myhb6blz6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf record: Apply affinity masks when reading mmap buffers

Build node cpu masks for mmap data buffers. Apply node cpu masks to tool
thread every time it references data buffers cross node or cross cpu.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/b25e4ebc-078d-2c7b-216c-f0bed108d073@linux.intel.com
[ Use cpu-set-sched.h to get the CPU_{EQUAL,OR}() fallbacks for older systems ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Add fallback versions for CPU_{OR,EQUAL}()

From the glibc sources, so that we can keep the tooling buildable in
older systems while using recent sched.h CPU_ macros.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/n/tip-hvm9ysmrjip75ebdzhzoh429@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf record: Bind the AIO user space buffers to nodes

Allocate and bind AIO user space buffers to the memory nodes that mmap
kernel buffers are bound to.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/5a5adebc-afe0-4806-81cd-180d49ec043f@linux.intel.com
[ Do not use 'index' as a variable name, it is a define in older glibcs ]
Link: http://lkml.kernel.org/r/20190205151526.GC10613@kernel.org
[ Add -lnuma to the python build when -DHAVE_LIBNUMA_SUPPORT is present, fixing 'perf test python' ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf record: Allocate affinity masks

Allocate affinity option and masks for mmap data buffers and record
thread as well as initialize allocated objects.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/526fa2b0-07de-6dbd-a7e9-26ba875593c9@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf pmu: Remove set_drv_config API

CoreSight was the only client of the PMU's set_drv_config() API.  Now
that it is no longer needed by CoreSight remove it from the code base.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-8-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf coresight: Remove set_drv_config() API

Now that the event's config2 attribute is used to communicate sink
selection to the kernel, remove the old set_drv_config() implementation
since it is no longer needed.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-7-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf arm cs-etm: Use event attributes to send sink information to kernel

The communication of sink information for a trace session doesn't work
when more than on CPU is involved in the scenario due to the static
nature of sysfs.  As such communicate the sink information to each event
by using the perf_event::attr:config2 attribute.  The information sent
to the kernel is an hash of the sink's name, which is unique in a
system.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-6-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf pmu: Move EVENT_SOURCE_DEVICE_PATH to PMU header file

Move definition of EVENT_SOURCE_DEVICE_PATH to pmu.h so that it can be
used by other files than pmu.c

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-5-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

coresight: Use event attributes for sink selection

This patch uses the information conveyed by perf_event::attr::config2
to select a sink to use for the session.  That way a sink can easily be
selected to be used by more than one source, something that isn't currently
possible with the sysfs implementation.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-4-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

coresight: perf: Add "sinks" group to PMU directory

Add a "sinks" directory entry so that users can see all the sinks
available in the system in a single place.  Individual sink are added
as they are registered with the coresight bus.

Committer tests:

Test built on a ubuntu 18.04 container with a cross build environment to
arm64, the new field is there, need to find a machine with this feature
to do further testing in the future.

  root@d15263e5734a:/git/perf# grep CORESIGHT /tmp/build/v5.0-rc2+/.config
  CONFIG_CORESIGHT=y
  CONFIG_CORESIGHT_LINKS_AND_SINKS=y
  CONFIG_CORESIGHT_LINK_AND_SINK_TMC=y
  CONFIG_CORESIGHT_CATU=y
  CONFIG_CORESIGHT_SINK_TPIU=y
  CONFIG_CORESIGHT_SINK_ETBV10=y
  CONFIG_CORESIGHT_SOURCE_ETM4X=y
  CONFIG_CORESIGHT_DYNAMIC_REPLICATOR=y
  CONFIG_CORESIGHT_STM=y
  CONFIG_CORESIGHT_CPU_DEBUG=m
  root@d15263e5734a:/git/perf#
  root@d15263e5734a:/git/perf# file /tmp/build/v5.0-rc2+/drivers/hwtracing/coresight/*.o
  .../coresight/coresight-catu.o:               ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-cpu-debug.mod.o:      ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-cpu-debug.o:          ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-dynamic-replicator.o: ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-etb10.o:              ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-etm-perf.o:           ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-etm4x-sysfs.o:        ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-etm4x.o:              ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-funnel.o:             ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-replicator.o:         ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-stm.o:                ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-tmc-etf.o:            ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-tmc-etr.o:            ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-tmc.o:                ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight-tpiu.o:               ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/coresight.o:                    ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  .../coresight/of_coresight.o:                 ELF 64-bit MSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
  root@d15263e5734a:/git/perf#

  root@d15263e5734a:/git/perf# pahole -C coresight_device /tmp/build/v5.0-rc2+/drivers/hwtracing/coresight/coresight.o
  struct coresight_device {
          struct coresight_connection * conns;             /*     0     8 */
          int                        nr_inport;            /*     8     4 */
          int                        nr_outport;           /*    12     4 */
          enum coresight_dev_type    type;                 /*    16     4 */
          union coresight_dev_subtype subtype;             /*    20     8 */

          /* XXX 4 bytes hole, try to pack */

          const struct coresight_ops  * ops;               /*    32     8 */
          struct device              dev;                  /*    40  1408 */

          /* XXX last struct has 7 bytes of padding */

          /* --- cacheline 22 boundary (1408 bytes) was 40 bytes ago --- */
          atomic_t *                 refcnt;               /*  1448     8 */
          bool                       orphan;               /*  1456     1 */
          bool                       enable;               /*  1457     1 */
          bool                       activated;            /*  1458     1 */

          /* XXX 5 bytes hole, try to pack */

          struct dev_ext_attribute * ea;                   /*  1464     8 */

          /* size: 1472, cachelines: 23, members: 12 */
          /* sum members: 1463, holes: 2, sum holes: 9 */
          /* paddings: 1, sum paddings: 7 */
  };
  root@d15263e5734a:/git/perf#

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-3-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf/aux: Make perf_event accessible to setup_aux()

When pmu::setup_aux() is called the coresight PMU needs to know which
sink to use for the session by looking up the information in the
event's attr::config2 field.

As such simply replace the cpu information by the complete perf_event
structure and change all affected customers.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki Poulouse <suzuki.poulose@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-2-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bpf-loader: Remove unecessary includes from bpf-loader.h

To cut the header dep tree, to get unecessary object rebuilds to be
reduced when a change happens in headers.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-ph72xhl9moqa0g1hxcyudwfn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf powerpc kvm-stat: Add missing evlist.h header

This header was being obtained indirectly, by sheer luck, add it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-c3h8oyav16iu5ivput8n4wt6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf kvm stat: Replace kvm-stat.h includes with forward declarations

To reduce the include header dependency tree and speed up perf builds.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-dngwaxuhfnhksawgdpo6e74n@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf pmu: Remove needless evsel.h include, only needs one fwd decl

To reduce the header dependency tree.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-rc389o1z0htwukqv6ni1viun@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tests pmu: Add missing headers

It needs the definitions for PATH_MAX and snprintf, was getting it
by luck from headers it included and that are now being sanitized.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-7bbh3kk0h5mywvfqm64nhv28@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf hist: Remove the needless callchain.h include from hist.h

Nothing that is provided by callchain.h is used there, just things that
should've be directly included in hist.h, such as rbtree.h and a
map_symbol forward declaration.

Remove it so that we reduce the headers dependency tree.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-zivvqfx93w5zzur7hr7h0nlh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Add missing include <callchain.h> in various places

Its getting it from hist.h and that will go away, as that header doesn't
need callchain.h at all.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-6ebl3mwwiqocl79yts44qltu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf thread: Don't include symbol.h, symbol_conf.h is enough

Also add stdio.h to get the FILE definition.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-8vx5396phynuxhdsxxfbdhsk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf evsel: No need to include symbol.h in evsel.h, symbol_conf.h is enough

To reduce the header dependency and avoid unnecessary rebuilds when
things change in symbol.h.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-6duflwliprh2tr47w5x4t260@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Add missing include for symbols.h

Several places were using definitions found in symbols.h but not
including it, getting it by sheer luck from some other headers that now
are in the process of removing that include because they don't need it
or because simply having struct forward declarations is enough, fix it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-xbcvvx296d70kpg9wb0qmeq9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf hist: Remove symbol.h from hist.h, just fwd decls are needed

To reduce the includes dependencies.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-cmvg5ght75mmfg1efeyna9rn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tests: Add missing headers so far obtained indirectly

We're going to remove symbol.h from some places and this breaks
some of the perf tests, fix it by adding the required includes.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-wpa4b6x0btpnh2kjxzl9no4w@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf map: Move structs and prototypes for map groups to a separate header

And since machine.h only needs what is in there, make it stop including
map.h and instead include this newly introduced map_groups.h instead.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-dbob25fv5rp2rjpwlnterf38@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

pref tools: Add missing map.h includes

Lots of places get the map.h file indirectly, and since we're going to
remove it from machine.h, then those need to include it directly, do it
now, before we remove that dep.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-ob8jehdjda8h5jsrv9dqj9tf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf symbols: Introduce map_symbol.h

To allow headers just wanting this definition to be able to get it
without all the things in symbol.h, to reduce the include dep tree.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-l32z2qyhs6fe8unf4gk2ead2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf callchain: Uninline callchain_cursor_reset() to remove map.h dependency

That was the only thing that made including map.h in callchain.h a
requiriment, so uninline it and just add a 'struct map' forward
declaration.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-7fjz4hvv1bpzqaeriku44fn4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf srccode: Move struct definition from map.h to srccode.h

To reduce the header dependencies, since we already have a srccode.h
header, then there is where the 'struct srccode_state' should be, and
map.h, that is more widely used should have just a forward declaraion
of 'struct srccode_state'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-64lrkjjaa7wlo1zi2gr5u3es@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf arm pmu: Add missing linux/string.h header

It uses strstarts(), that is defined in linux/string.h but that was
being including by sheer luck, indirectly, fix it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Dongjiu Geng <gengdongjiu@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/n/tip-vub5lp82wb7vy5wssfad0xu8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf powerpc: Add missing headers to skip-callchain-idx.c

It uses several structs but don't explicitely includes the headers where
they are defined, getting them by sheer luck from one of the headers it
includes, since those are being streamlined to avoid unnecessary
rebuilds when changes are made to a random header, they will break, fix
them now so that they continue to build.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Maynard Johnson <maynard@us.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/n/tip-j1nyksegpnz36wi3qx2p46i1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf/ring_buffer: Convert ring_buffer.aux_refcount to refcount_t

atomic_t variables are currently used to implement reference
counters with the following properties:

 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable ring_buffer.aux_refcount is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

** Important note for maintainers:

Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts. Please check Documentation/core-api/refcount-vs-atomic.rst
for more information.

Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.

For the ring_buffer.aux_refcount it might make a difference
in following places:

 - perf_aux_output_begin(): increment in refcount_inc_not_zero() only
   guarantees control dependency on success vs. fully ordered
   atomic counterpart
 - rb_free_aux(): decrement in refcount_dec_and_test() only
   provides RELEASE ordering and ACQUIRE ordering + control dependency
   on success vs. fully ordered atomic counterpart

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
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: acme@kernel.org
Cc: namhyung@kernel.org
Link: https://lkml.kernel.org/r/1548678448-24458-4-git-send-email-elena.reshetova@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

perf/ring_buffer: Convert ring_buffer.refcount to refcount_t

atomic_t variables are currently used to implement reference
counters with the following properties:

 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable ring_buffer.refcount is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

** Important note for maintainers:

Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts. Please check Documentation/core-api/refcount-vs-atomic.rst
for more information.

Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.

For the ring_buffer.refcount it might make a difference
in following places:

 - ring_buffer_get(): increment in refcount_inc_not_zero() only
   guarantees control dependency on success vs. fully ordered
   atomic counterpart
 - ring_buffer_put(): decrement in refcount_dec_and_test() only
   provides RELEASE ordering and ACQUIRE ordering + control dependency
   on success vs. fully ordered atomic counterpart

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
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: acme@kernel.org
Cc: namhyung@kernel.org
Link: https://lkml.kernel.org/r/1548678448-24458-3-git-send-email-elena.reshetova@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

perf: Convert perf_event_context.refcount to refcount_t

atomic_t variables are currently used to implement reference
counters with the following properties:

 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable perf_event_context.refcount is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

** Important note for maintainers:

Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts. Please check Documentation/core-api/refcount-vs-atomic.rst
for more information.

Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.

For the perf_event_context.refcount it might make a difference
in following places:

 - get_ctx(), perf_event_ctx_lock_nested(), perf_lock_task_context()
   and __perf_event_ctx_lock_double(): increment in
   refcount_inc_not_zero() only guarantees control dependency
   on success vs. fully ordered atomic counterpart
 - put_ctx(): decrement in refcount_dec_and_test() provides
   RELEASE ordering and ACQUIRE ordering + control dependency on success
   vs. fully ordered atomic counterpart

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
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: acme@kernel.org
Cc: namhyung@kernel.org
Link: https://lkml.kernel.org/r/1548678448-24458-2-git-send-email-elena.reshetova@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

perf/uprobes: Convert to SPDX license identifier

Replace the license boiler plate with a SPDX license identifier.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Paul McKenney <paulmck@linux.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190116111308.211981422@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

perf/hw_breakpoints: Convert to SPDX license identifier

Replace the license boiler plate with a SPDX license identifier.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Paul McKenney <paulmck@linux.ibm.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190116111308.105855650@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

perf/core: Convert to SPDX license identifiers

Use proper SPDX license identifiers instead of the bogus reference to
kernel-base/COPYING.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190116111308.012666937@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge branch 'perf/urgent' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

perf/core: Don't WARN() for impossible ring-buffer sizes

The perf tool uses /proc/sys/kernel/perf_event_mlock_kb to determine how
large its ringbuffer mmap should be. This can be configured to arbitrary
values, which can be larger than the maximum possible allocation from
kmalloc.

When this is configured to a suitably large value (e.g. thanks to the
perf fuzzer), attempting to use perf record triggers a WARN_ON_ONCE() in
__alloc_pages_nodemask():

   WARNING: CPU: 2 PID: 5666 at mm/page_alloc.c:4511 __alloc_pages_nodemask+0x3f8/0xbc8

Let's avoid this by checking that the requested allocation is possible
before calling kzalloc.

Reported-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
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: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20190110142745.25495-1-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

perf/x86/intel: Delay memory deallocation until x86_pmu_dead_cpu()

intel_pmu_cpu_prepare() allocated memory for ->shared_regs among other
members of struct cpu_hw_events. This memory is released in
intel_pmu_cpu_dying() which is wrong. The counterpart of the
intel_pmu_cpu_prepare() callback is x86_pmu_dead_cpu().

Otherwise if the CPU fails on the UP path between CPUHP_PERF_X86_PREPARE
and CPUHP_AP_PERF_X86_STARTING then it won't release the memory but
allocate new memory on the next attempt to online the CPU (leaking the
old memory).
Also, if the CPU down path fails between CPUHP_AP_PERF_X86_STARTING and
CPUHP_PERF_X86_PREPARE then the CPU will go back online but never
allocate the memory that was released in x86_pmu_dying_cpu().

Make the memory allocation/free symmetrical in regard to the CPU hotplug
notifier by moving the deallocation to intel_pmu_cpu_dead().

This started in commit:

   a7e3ed1e47011 ("perf: Add support for supplementary event registers").

In principle the bug was introduced in v2.6.39 (!), but it will almost
certainly not backport cleanly across the big CPU hotplug rewrite between v4.7-v4.15...

[ bigeasy: Added patch description. ]
[ mingo: Added backporting guidance. ]

Reported-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # With developer hat on
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # With maintainer hat on
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: acme@kernel.org
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: jolsa@kernel.org
Cc: kan.liang@linux.intel.com
Cc: namhyung@kernel.org
Cc: <stable@vger.kernel.org>
Fixes: a7e3ed1e47011 ("perf: Add support for supplementary event registers").
Link: https://lkml.kernel.org/r/20181219165350.6s3jvyxbibpvlhtq@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

perf/x86/intel/uncore: Add Node ID mask

Some PCI uncore PMUs cannot be registered on an 8-socket system (HPE
Superdome Flex).

To understand which Socket the PCI uncore PMUs belongs to, perf retrieves
the local Node ID of the uncore device from CPUNODEID(0xC0) of the PCI
configuration space, and the mapping between Socket ID and Node ID from
GIDNIDMAP(0xD4). The Socket ID can be calculated accordingly.

The local Node ID is only available at bit 2:0, but current code doesn't
mask it. If a BIOS doesn't clear the rest of the bits, an incorrect Node ID
will be fetched.

Filter the Node ID by adding a mask.

Reported-by: Song Liu <songliubraving@fb.com>
Tested-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.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: <stable@vger.kernel.org> # v3.7+
Fixes: 7c94ee2e0917 ("perf/x86: Add Intel Nehalem and Sandy Bridge-EP uncore support")
Link: https://lkml.kernel.org/r/1548600794-33162-1-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Linux 5.0-rc5

Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "A few updates for x86:

   - Fix an unintended sign extension issue in the fault handling code

   - Rename the new resource control config switch so it's less
     confusing

   - Avoid setting up EFI info in kexec when the EFI runtime is
     disabled.

   - Fix the microcode version check in the AMD microcode loader so it
     only loads higher version numbers and never downgrades

   - Set EFER.LME in the 32bit trampoline before returning to long mode
     to handle older AMD/KVM behaviour properly.

   - Add Darren and Andy as x86/platform reviewers"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Avoid confusion over the new X86_RESCTRL config
  x86/kexec: Don't setup EFI info if EFI runtime is not enabled
  x86/microcode/amd: Don't falsely trick the late loading mechanism
  MAINTAINERS: Add Andy and Darren as arch/x86/platform/ reviewers
  x86/fault: Fix sign-extend unintended sign extension
  x86/boot/compressed/64: Set EFER.LME=1 in 32-bit trampoline before returning to long mode
  x86/cpu: Add Atom Tremont (Jacobsville)

Merge branch 'smp-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull cpu hotplug fixes from Thomas Gleixner:
 "Two fixes for the cpu hotplug machinery:

   - Replace the overly clever 'SMT disabled by BIOS' detection logic as
     it breaks KVM scenarios and prevents speculation control updates
     when the Hyperthreads are brought online late after boot.

   - Remove a redundant invocation of the speculation control update
     function"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Fix "SMT disabled by BIOS" detection for KVM
  x86/speculation: Remove redundant arch_smt_update() invocation

Merge branch 'perf-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull perf fixes from Thomas Gleixner:
 "A pile of perf updates:

   - Fix broken sanity check in the /proc/sys/kernel/perf_cpu_time_max_percent
     write handler

   - Cure a perf script crash which caused by an unitinialized data
     structure

   - Highlight the hottest instruction in perf top and not a random one

   - Cure yet another clang issue when building perf python

   - Handle topology entries with no CPU correctly in the tools

   - Handle perf data which contains both tracepoints and performance
     counter entries correctly.

   - Add a missing NULL pointer check in perf ordered_events_free()"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf script: Fix crash when processing recorded stat data
  perf top: Fix wrong hottest instruction highlighted
  perf tools: Handle TOPOLOGY headers with no CPU
  perf python: Remove -fstack-clash-protection when building with some clang versions
  perf core: Fix perf_proc_update_handler() bug
  perf script: Fix crash with printing mixed trace point and other events
  perf ordered_events: Fix crash in ordered_events__free

Merge branch 'efi-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull EFI fix from Thomas Gleixner:
 "The dump info for the efi page table debugging lacks a terminator
  which causes the kernel to crash when the debugfile is read"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/arm64: Fix debugfs crash by adding a terminator for ptdump marker

Merge tag 'for-5.0-rc4-tag' of git://git./linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - regression fix: transaction commit can run away due to delayed ref
   waiting heuristic, this is not necessary now because of the proper
   reservation mechanism introduced in 5.0

 - regression fix: potential crash due to use-before-check of an ERR_PTR
   return value

 - fix for transaction abort during transaction commit that needs to
   properly clean up pending block groups

 - fix deadlock during b-tree node/leaf splitting, when this happens on
   some of the fundamental trees, we must prevent new tree block
   allocation to re-enter indirectly via the block group flushing path

 - potential memory leak after errors during mount

* tag 'for-5.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: On error always free subvol_name in btrfs_mount
  btrfs: clean up pending block groups when transaction commit aborts
  btrfs: fix potential oops in device_list_add
  btrfs: don't end the transaction for delayed refs in throttle
  Btrfs: fix deadlock when allocating tree block during leaf/node split

Merge tag 'devicetree-fixes-for-5.0-3' of git://git./linux/kernel/git/robh/linux

Pull Devicetree fix from Rob Herring:
 "A single fix for building DT bindings in-tree"

* tag 'devicetree-fixes-for-5.0-3' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  dt-bindings: Fix dt_binding_check target for in tree builds

Merge tag 'riscv-for-linus-5.0-rc5' of git://git./linux/kernel/git/palmer/riscv-linux

Pull RISC-V fixes from Palmer Dabbelt:
 "This contains a handful of mostly-independent patches:

   - make our port respect TIF_NEED_RESCHED, which fixes
     CONFIG_PREEMPT=y kernels

   - fix double-put of OF nodes

   - fix a misspelling of target in our Kconfig

   - generic PCIe is enabled in our defconfig

   - fix our SBI early console to properly handle line
     endings

   - fix max_low_pfn being counted in PFNs

   - a change to TASK_UNMAPPED_BASE to match what other
     arches do

  This has passed my standard 'boot Fedora' flow"

* tag 'riscv-for-linus-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
  riscv: Adjust mmap base address at a third of task size
  riscv: fixup max_low_pfn with PFN_DOWN.
  tty/serial: use uart_console_write in the RISC-V SBL early console
  RISC-V: defconfig: Add CRYPTO_DEV_VIRTIO=y
  RISC-V: defconfig: Enable Generic PCIE by default
  RISC-V: defconfig: Move CONFIG_PCI{,E_XILINX}
  RISC-V: Kconfig: fix spelling mistake "traget" -> "target"
  RISC-V: asm/page.h: fix spelling mistake "CONFIG_64BITS" -> "CONFIG_64BIT"
  RISC-V: fix bad use of of_node_put
  RISC-V: Add _TIF_NEED_RESCHED check for kernel thread when CONFIG_PREEMPT=y

Merge tag 'for-linus-20190202' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "A few fixes that should go into this release. This contains:

   - MD pull request from Song, fixing a recovery OOM issue (Alexei)

   - Fix for a sync related stall (Jianchao)

   - Dummy callback for timeouts (Tetsuo)

   - IDE atapi sense ordering fix (me)"

* tag 'for-linus-20190202' of git://git.kernel.dk/linux-block:
  ide: ensure atapi sense request aren't preempted
  blk-mq: fix a hung issue when fsync
  block: pass no-op callback to INIT_WORK().
  md/raid5: fix 'out of memory' during raid cache recovery

Merge tag 'scsi-fixes' of git://git./linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Five minor bug fixes.

  The libfc one is a tiny memory leak, the zfcp one is an incorrect user
  visible parameter and the rest are on error legs or obscure features"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: 53c700: pass correct "dev" to dma_alloc_attrs()
  scsi: bnx2fc: Fix error handling in probe()
  scsi: scsi_debug: fix write_same with virtual_gb problem
  scsi: libfc: free skb when receiving invalid flogi resp
  scsi: zfcp: fix sysfs block queue limit output for max_segment_size

Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "24 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (24 commits)
  autofs: fix error return in autofs_fill_super()
  autofs: drop dentry reference only when it is never used
  fs/drop_caches.c: avoid softlockups in drop_pagecache_sb()
  mm: migrate: don't rely on __PageMovable() of newpage after unlocking it
  psi: clarify the Kconfig text for the default-disable option
  mm, memory_hotplug: __offline_pages fix wrong locking
  mm: hwpoison: use do_send_sig_info() instead of force_sig()
  kasan: mark file common so ftrace doesn't trace it
  init/Kconfig: fix grammar by moving a closing parenthesis
  lib/test_kmod.c: potential double free in error handling
  mm, oom: fix use-after-free in oom_kill_process
  mm/hotplug: invalid PFNs from pfn_to_online_page()
  mm,memory_hotplug: fix scan_movable_pages() for gigantic hugepages
  psi: fix aggregation idle shut-off
  mm, memory_hotplug: test_pages_in_a_zone do not pass the end of zone
  mm, memory_hotplug: is_mem_section_removable do not pass the end of a zone
  oom, oom_reaper: do not enqueue same task twice
  mm: migrate: make buffer_migrate_page_norefs() actually succeed
  kernel/exit.c: release ptraced tasks before zap_pid_ns_processes
  x86_64: increase stack size for KASAN_EXTRA
  ...

efi/arm64: Fix debugfs crash by adding a terminator for ptdump marker

When reading 'efi_page_tables' debugfs triggers an out-of-bounds access here:

  arch/arm64/mm/dump.c: 282
  if (addr >= st->marker[1].start_address) {

called from:

  arch/arm64/mm/dump.c: 331
  note_page(st, addr, 2, pud_val(pud));

because st->marker++ is is called after "UEFI runtime end" which is the
last element in addr_marker[]. Therefore, add a terminator like the one
for kernel_page_tables, so it can be skipped to print out non-existent
markers.

Here's the KASAN bug report:

  # cat /sys/kernel/debug/efi_page_tables
  ---[ UEFI runtime start ]---
  0x0000000020000000-0x0000000020010000          64K PTE       RW NX SHD AF ...
  0x0000000020200000-0x0000000021340000       17664K PTE       RW NX SHD AF ...
  ...
  0x0000000021920000-0x0000000021950000         192K PTE       RW x  SHD AF ...
  0x0000000021950000-0x00000000219a0000         320K PTE       RW NX SHD AF ...
  ---[ UEFI runtime end ]---
  ---[ (null) ]---
  ---[ (null) ]---

   BUG: KASAN: global-out-of-bounds in note_page+0x1f0/0xac0
   Read of size 8 at addr ffff2000123f2ac0 by task read_all/42464
   Call trace:
    dump_backtrace+0x0/0x298
    show_stack+0x24/0x30
    dump_stack+0xb0/0xdc
    print_address_description+0x64/0x2b0
    kasan_report+0x150/0x1a4
    __asan_report_load8_noabort+0x30/0x3c
    note_page+0x1f0/0xac0
    walk_pgd+0xb4/0x244
    ptdump_walk_pgd+0xec/0x140
    ptdump_show+0x40/0x50
    seq_read+0x3f8/0xad0
    full_proxy_read+0x9c/0xc0
    __vfs_read+0xfc/0x4c8
    vfs_read+0xec/0x208
    ksys_read+0xd0/0x15c
    __arm64_sys_read+0x84/0x94
    el0_svc_handler+0x258/0x304
    el0_svc+0x8/0xc

  The buggy address belongs to the variable:
   __compound_literal.0+0x20/0x800

  Memory state around the buggy address:
   ffff2000123f2980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
   ffff2000123f2a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fa
  >ffff2000123f2a80: fa fa fa fa 00 00 00 00 fa fa fa fa 00 00 00 00
                                            ^
   ffff2000123f2b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
   ffff2000123f2b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0

[ ardb: fix up whitespace ]
[ mingo: fix up some moar ]

Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 9d80448ac92b ("efi/arm64: Add debugfs node to dump UEFI runtime page tables")
Link: http://lkml.kernel.org/r/20190202095017.13799-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/resctrl: Avoid confusion over the new X86_RESCTRL config

"Resource Control" is a very broad term for this CPU feature, and a term
that is also associated with containers, cgroups etc. This can easily
cause confusion.

Make the user prompt more specific. Match the config symbol name.

 [ bp: In the future, the corresponding ARM arch-specific code will be
   under ARM_CPU_RESCTRL and the arch-agnostic bits will be carved out
   under the CPU_RESCTRL umbrella symbol. ]

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Babu Moger <Babu.Moger@amd.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morse <james.morse@arm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: linux-doc@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190130195621.GA30653@cmpxchg.org

Merge tag 'xtensa-20190201' of git://github.com/jcmvbkbc/linux-xtensa

Pull xtensa fixes from Max Filippov:

 - fix ccount_timer_shutdown for secondary CPUs

 - fix secondary CPU initialization

 - fix secondary CPU reset vector clash with double exception vector

 - fix present CPUs when booting with 'maxcpus' parameter

 - limit possible CPUs by configured NR_CPUS

 - issue a warning if xtensa PIC is asked to retrigger anything other
   than software IRQ

 - fix masking/unmasking of the first two IRQs on xtensa MX PIC

 - fix typo in Kconfig description for user space unaligned access
   feature

 - fix Kconfig warning for selecting BUILTIN_DTB

* tag 'xtensa-20190201' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: SMP: limit number of possible CPUs by NR_CPUS
  xtensa: rename BUILTIN_DTB to BUILTIN_DTB_SOURCE
  xtensa: Fix typo use space=>user space
  drivers/irqchip: xtensa-mx: fix mask and unmask
  drivers/irqchip: xtensa: add warning to irq_retrigger
  xtensa: SMP: mark each possible CPU as present
  xtensa: smp_lx200_defconfig: fix vectors clash
  xtensa: SMP: fix secondary CPU initialization
  xtensa: SMP: fix ccount_timer_shutdown

Merge tag 'arm64-fixes' of git://git./linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "Although we're still debugging a few minor arm64-specific issues in
  mainline, I didn't want to hold this lot up in the meantime.

  We've got an additional KASLR fix after the previous one wasn't quite
  complete, a fix for a performance regression when mapping executable
  pages into userspace and some fixes for kprobe blacklisting. All
  candidates for stable.

  Summary:

   - Fix module loading when KASLR is configured but disabled at runtime

   - Fix accidental IPI when mapping user executable pages

   - Ensure hyp-stub and KVM world switch code cannot be kprobed"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: hibernate: Clean the __hyp_text to PoC after resume
  arm64: hyp-stub: Forbid kprobing of the hyp-stub
  arm64: kprobe: Always blacklist the KVM world-switch code
  arm64: kaslr: ensure randomized quantities are clean also when kaslr is off
  arm64: Do not issue IPIs for user executable ptes

Merge tag '5.0-rc4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull smb3 fixes from Steve French:
 "SMB3 fixes, some from this week's SMB3 test evemt, 5 for stable and a
  particularly important one for queryxattr (see xfstests 70 and 117)"

* tag '5.0-rc4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: update internal module version number
  CIFS: fix use-after-free of the lease keys
  CIFS: Do not consider -ENODATA as stat failure for reads
  CIFS: Do not count -ENODATA as failure for query directory
  CIFS: Fix trace command logging for SMB2 reads and writes
  CIFS: Fix possible oops and memory leaks in async IO
  cifs: limit amount of data we request for xattrs to CIFSMaxBufSize
  cifs: fix computation for MAX_SMB2_HDR_SIZE

Merge tag 'apparmor-pr-2019-02-01' of git://git./linux/kernel/git/jj/linux-apparmor

Pull apparmor bug fixes from John Johansen:
 "Two bug fixes for apparmor:

   - Fix aa_label_build() error handling for failed merges

   - Fix warning about unused function apparmor_ipv6_postroute"

* tag 'apparmor-pr-2019-02-01' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
  apparmor: Fix aa_label_build() error handling for failed merges
  apparmor: Fix warning about unused function apparmor_ipv6_postroute

autofs: fix error return in autofs_fill_super()

In autofs_fill_super() on error of get inode/make root dentry the return
should be ENOMEM as this is the only failure case of the called
functions.

Link: http://lkml.kernel.org/r/154725123240.11260.796773942606871359.stgit@pluto-themaw-net
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

autofs: drop dentry reference only when it is never used

autofs_expire_run() calls dput(dentry) to drop the reference count of
dentry.  However, dentry is read via autofs_dentry_ino(dentry) after
that.  This may result in a use-free-bug.  The patch drops the reference
count of dentry only when it is never used.

Link: http://lkml.kernel.org/r/154725122396.11260.16053424107144453867.stgit@pluto-themaw-net
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/drop_caches.c: avoid softlockups in drop_pagecache_sb()

When superblock has lots of inodes without any pagecache (like is the
case for /proc), drop_pagecache_sb() will iterate through all of them
without dropping sb->s_inode_list_lock which can lead to softlockups
(one of our customers hit this).

Fix the problem by going to the slow path and doing cond_resched() in
case the process needs rescheduling.

Link: http://lkml.kernel.org/r/20190114085343.15011-1-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: migrate: don't rely on __PageMovable() of newpage after unlocking it

We had a race in the old balloon compaction code before b1123ea6d3b3
("mm: balloon: use general non-lru movable page feature") refactored it
that became visible after backporting 195a8c43e93d ("virtio-balloon:
deflate via a page list") without the refactoring.

The bug existed from commit d6d86c0a7f8d ("mm/balloon_compaction:
redesign ballooned pages management") till b1123ea6d3b3 ("mm: balloon:
use general non-lru movable page feature").  d6d86c0a7f8d
("mm/balloon_compaction: redesign ballooned pages management") was
backported to 3.12, so the broken kernels are stable kernels [3.12 -
4.7].

There was a subtle race between dropping the page lock of the newpage in
__unmap_and_move() and checking for __is_movable_balloon_page(newpage).

Just after dropping this page lock, virtio-balloon could go ahead and
deflate the newpage, effectively dequeueing it and clearing PageBalloon,
in turn making __is_movable_balloon_page(newpage) fail.

This resulted in dropping the reference of the newpage via
putback_lru_page(newpage) instead of put_page(newpage), leading to
page->lru getting modified and a !LRU page ending up in the LRU lists.
With 195a8c43e93d ("virtio-balloon: deflate via a page list")
backported, one would suddenly get corrupted lists in
release_pages_balloon():

- WARNING: CPU: 13 PID: 6586 at lib/list_debug.c:59 __list_del_entry+0xa1/0xd0
- list_del corruption. prev->next should be ffffe253961090a0, but was dead000000000100

Nowadays this race is no longer possible, but it is hidden behind very
ugly handling of __ClearPageMovable() and __PageMovable().

__ClearPageMovable() will not make __PageMovable() fail, only
PageMovable().  So the new check (__PageMovable(newpage)) will still
hold even after newpage was dequeued by virtio-balloon.

If anybody would ever change that special handling, the BUG would be
introduced again.  So instead, make it explicit and use the information
of the original isolated page before migration.

This patch can be backported fairly easy to stable kernels (in contrast
to the refactoring).

Link: http://lkml.kernel.org/r/20190129233217.10747-1-david@redhat.com
Fixes: d6d86c0a7f8d ("mm/balloon_compaction: redesign ballooned pages management")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reported-by: Vratislav Bendel <vbendel@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vratislav Bendel <vbendel@redhat.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: <stable@vger.kernel.org> [3.12 - 4.7]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

psi: clarify the Kconfig text for the default-disable option

The current help text caused some confusion in online forums about
whether or not to default-enable or default-disable psi in vendor
kernels.  This is because it doesn't communicate the reason for why we
made this setting configurable in the first place: that the overhead is
non-zero in an artificial scheduler stress test.

Since this isn't representative of real workloads, and the effect was
not measurable in scheduler-heavy real world applications such as the
webservers and memcache installations at Facebook, it's fair to point
out that this is a pretty cautious option to select.

Link: http://lkml.kernel.org/r/20190129233617.16767-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm, memory_hotplug: __offline_pages fix wrong locking

Jan has noticed that we do double unlock on some failure paths when
offlining a page range.  This is indeed the case when
test_pages_in_a_zone respp.  start_isolate_page_range fail.  This was an
omission when forward porting the debugging patch from an older kernel.

Fix the issue by dropping mem_hotplug_done from the failure condition
and keeping the single unlock in the catch all failure path.

Link: http://lkml.kernel.org/r/20190115120307.22768-1-mhocko@kernel.org
Fixes: 7960509329c2 ("mm, memory_hotplug: print reason for the offlining failure")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Tested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: hwpoison: use do_send_sig_info() instead of force_sig()

Currently memory_failure() is racy against process's exiting, which
results in kernel crash by null pointer dereference.

The root cause is that memory_failure() uses force_sig() to forcibly
kill asynchronous (meaning not in the current context) processes.  As
discussed in thread https://lkml.org/lkml/2010/6/8/236 years ago for OOM
fixes, this is not a right thing to do.  OOM solves this issue by using
do_send_sig_info() as done in commit d2d393099de2 ("signal:
oom_kill_task: use SEND_SIG_FORCED instead of force_sig()"), so this
patch is suggesting to do the same for hwpoison.  do_send_sig_info()
properly accesses to siglock with lock_task_sighand(), so is free from
the reported race.

I confirmed that the reported bug reproduces with inserting some delay
in kill_procs(), and it never reproduces with this patch.

Note that memory_failure() can send another type of signal using
force_sig_mceerr(), and the reported race shouldn't happen on it because
force_sig_mceerr() is called only for synchronous processes (i.e.
BUS_MCEERR_AR happens only when some process accesses to the corrupted
memory.)

Link: http://lkml.kernel.org/r/20190116093046.GA29835@hori1.linux.bs1.fc.nec.co.jp
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reported-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
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>

kasan: mark file common so ftrace doesn't trace it

When option CONFIG_KASAN is enabled toghether with ftrace, function
ftrace_graph_caller() gets in to a recursion, via functions
kasan_check_read() and kasan_check_write().

 Breakpoint 2, ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:179
 179             mcount_get_pc             x0    //     function's pc
 (gdb) bt
 #0  ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:179
 #1  0xffffff90101406c8 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:151
 #2  0xffffff90106fd084 in kasan_check_write (p=0xffffffc06c170878, size=4) at ../mm/kasan/common.c:105
 #3  0xffffff90104a2464 in atomic_add_return (v=<optimized out>, i=<optimized out>) at ./include/generated/atomic-instrumented.h:71
 #4  atomic_inc_return (v=<optimized out>) at ./include/generated/atomic-fallback.h:284
 #5  trace_graph_entry (trace=0xffffffc03f5ff380) at ../kernel/trace/trace_functions_graph.c:441
 #6  0xffffff9010481774 in trace_graph_entry_watchdog (trace=<optimized out>) at ../kernel/trace/trace_selftest.c:741
 #7  0xffffff90104a185c in function_graph_enter (ret=<optimized out>, func=<optimized out>, frame_pointer=18446743799894897728, retp=<optimized out>) at ../kernel/trace/trace_functions_graph.c:196
 #8  0xffffff9010140628 in prepare_ftrace_return (self_addr=18446743592948977792, parent=0xffffffc03f5ff418, frame_pointer=18446743799894897728) at ../arch/arm64/kernel/ftrace.c:231
 #9  0xffffff90101406f4 in ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:182
 Backtrace stopped: previous frame identical to this frame (corrupt stack?)
 (gdb)

Rework so that the kasan implementation isn't traced.

Link: http://lkml.kernel.org/r/20181212183447.15890-1-anders.roxell@linaro.org
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

init/Kconfig: fix grammar by moving a closing parenthesis

Link: http://lkml.kernel.org/r/20190129150813.15785-1-j.neuschaefer@gmx.net
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/test_kmod.c: potential double free in error handling

There is a copy and paste bug so we set "config->test_driver" to NULL
twice instead of setting "config->test_fs".  Smatch complains that it
leads to a double free:

  lib/test_kmod.c:840 __kmod_config_init() warn: 'config->test_fs' double freed

Link: http://lkml.kernel.org/r/20190121140011.GA14283@kadam
Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm, oom: fix use-after-free in oom_kill_process

Syzbot instance running on upstream kernel found a use-after-free bug in
oom_kill_process.  On further inspection it seems like the process
selected to be oom-killed has exited even before reaching
read_lock(&tasklist_lock) in oom_kill_process().  More specifically the
tsk->usage is 1 which is due to get_task_struct() in oom_evaluate_task()
and the put_task_struct within for_each_thread() frees the tsk and
for_each_thread() tries to access the tsk.  The easiest fix is to do
get/put across the for_each_thread() on the selected task.

Now the next question is should we continue with the oom-kill as the
previously selected task has exited? However before adding more
complexity and heuristics, let's answer why we even look at the children
of oom-kill selected task? The select_bad_process() has already selected
the worst process in the system/memcg.  Due to race, the selected
process might not be the worst at the kill time but does that matter?
The userspace can use the oom_score_adj interface to prefer children to
be killed before the parent.  I looked at the history but it seems like
this is there before git history.

Link: http://lkml.kernel.org/r/20190121215850.221745-1-shakeelb@google.com
Reported-by: syzbot+7fbbfa368521945f0e3d@syzkaller.appspotmail.com
Fixes: 6b0c81b3be11 ("mm, oom: reduce dependency on tasklist_lock")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/hotplug: invalid PFNs from pfn_to_online_page()

On an arm64 ThunderX2 server, the first kmemleak scan would crash [1]
with CONFIG_DEBUG_VM_PGFLAGS=y due to page_to_nid() found a pfn that is
not directly mapped (MEMBLOCK_NOMAP).  Hence, the page->flags is
uninitialized.

This is due to the commit 9f1eb38e0e11 ("mm, kmemleak: little
optimization while scanning") starts to use pfn_to_online_page() instead
of pfn_valid().  However, in the CONFIG_MEMORY_HOTPLUG=y case,
pfn_to_online_page() does not call memblock_is_map_memory() while
pfn_valid() does.

Historically, the commit 68709f45385a ("arm64: only consider memblocks
with NOMAP cleared for linear mapping") causes pages marked as nomap
being no long reassigned to the new zone in memmap_init_zone() by
calling __init_single_page().

Since the commit 2d070eab2e82 ("mm: consider zone which is not fully
populated to have holes") introduced pfn_to_online_page() and was
designed to return a valid pfn only, but it is clearly broken on arm64.

Therefore, let pfn_to_online_page() call pfn_valid_within(), so it can
handle nomap thanks to the commit f52bb98f5ade ("arm64: mm: always
enable CONFIG_HOLES_IN_ZONE"), while it will be optimized away on
architectures where have no HOLES_IN_ZONE.

[1]
  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000006
  Mem abort info:
    ESR = 0x96000005
    Exception class = DABT (current EL), IL = 32 bits
    SET = 0, FnV = 0
    EA = 0, S1PTW = 0
  Data abort info:
    ISV = 0, ISS = 0x00000005
    CM = 0, WnR = 0
  Internal error: Oops: 96000005 [#1] SMP
  CPU: 60 PID: 1408 Comm: kmemleak Not tainted 5.0.0-rc2+ #8
  pstate: 60400009 (nZCv daif +PAN -UAO)
  pc : page_mapping+0x24/0x144
  lr : __dump_page+0x34/0x3dc
  sp : ffff00003a5cfd10
  x29: ffff00003a5cfd10 x28: 000000000000802f
  x27: 0000000000000000 x26: 0000000000277d00
  x25: ffff000010791f56 x24: ffff7fe000000000
  x23: ffff000010772f8b x22: ffff00001125f670
  x21: ffff000011311000 x20: ffff000010772f8b
  x19: fffffffffffffffe x18: 0000000000000000
  x17: 0000000000000000 x16: 0000000000000000
  x15: 0000000000000000 x14: ffff802698b19600
  x13: ffff802698b1a200 x12: ffff802698b16f00
  x11: ffff802698b1a400 x10: 0000000000001400
  x9 : 0000000000000001 x8 : ffff00001121a000
  x7 : 0000000000000000 x6 : ffff0000102c53b8
  x5 : 0000000000000000 x4 : 0000000000000003
  x3 : 0000000000000100 x2 : 0000000000000000
  x1 : ffff000010772f8b x0 : ffffffffffffffff
  Process kmemleak (pid: 1408, stack limit = 0x(____ptrval____))
  Call trace:
   page_mapping+0x24/0x144
   __dump_page+0x34/0x3dc
   dump_page+0x28/0x4c
   kmemleak_scan+0x4ac/0x680
   kmemleak_scan_thread+0xb4/0xdc
   kthread+0x12c/0x13c
   ret_from_fork+0x10/0x18
  Code: d503201f f9400660 36000040 d1000413 (f9400661)
  ---[ end trace 4d4bd7f573490c8e ]---
  Kernel panic - not syncing: Fatal exception
  SMP: stopping secondary CPUs
  Kernel Offset: disabled
  CPU features: 0x002,20000c38
  Memory Limit: none
  ---[ end Kernel panic - not syncing: Fatal exception ]---

Link: http://lkml.kernel.org/r/20190122132916.28360-1-cai@lca.pw
Fixes: 9f1eb38e0e11 ("mm, kmemleak: little optimization while scanning")
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm,memory_hotplug: fix scan_movable_pages() for gigantic hugepages

This is the same sort of error we saw in commit 17e2e7d7e1b8 ("mm,
page_alloc: fix has_unmovable_pages for HugePages").

Gigantic hugepages cross several memblocks, so it can be that the page
we get in scan_movable_pages() is a page-tail belonging to a
1G-hugepage.  If that happens, page_hstate()->size_to_hstate() will
return NULL, and we will blow up in hugepage_migration_supported().

The splat is as follows:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
  #PF error: [normal kernel read fault]
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP PTI
  CPU: 1 PID: 1350 Comm: bash Tainted: G            E     5.0.0-rc1-mm1-1-default+ #27
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
  RIP: 0010:__offline_pages+0x6ae/0x900
  Call Trace:
   memory_subsys_offline+0x42/0x60
   device_offline+0x80/0xa0
   state_store+0xab/0xc0
   kernfs_fop_write+0x102/0x180
   __vfs_write+0x26/0x190
   vfs_write+0xad/0x1b0
   ksys_write+0x42/0x90
   do_syscall_64+0x5b/0x180
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  Modules linked in: af_packet(E) xt_tcpudp(E) ipt_REJECT(E) xt_conntrack(E) nf_conntrack(E) nf_defrag_ipv4(E) ip_set(E) nfnetlink(E) ebtable_nat(E) ebtable_broute(E) bridge(E) stp(E) llc(E) iptable_mangle(E) iptable_raw(E) iptable_security(E) ebtable_filter(E) ebtables(E) iptable_filter(E) ip_tables(E) x_tables(E) kvm_intel(E) kvm(E) irqbypass(E) crct10dif_pclmul(E) crc32_pclmul(E) ghash_clmulni_intel(E) bochs_drm(E) ttm(E) aesni_intel(E) drm_kms_helper(E) aes_x86_64(E) crypto_simd(E) cryptd(E) glue_helper(E) drm(E) virtio_net(E) syscopyarea(E) sysfillrect(E) net_failover(E) sysimgblt(E) pcspkr(E) failover(E) i2c_piix4(E) fb_sys_fops(E) parport_pc(E) parport(E) button(E) btrfs(E) libcrc32c(E) xor(E) zstd_decompress(E) zstd_compress(E) xxhash(E) raid6_pq(E) sd_mod(E) ata_generic(E) ata_piix(E) ahci(E) libahci(E) libata(E) crc32c_intel(E) serio_raw(E) virtio_pci(E) virtio_ring(E) virtio(E) sg(E) scsi_mod(E) autofs4(E)

[akpm@linux-foundation.org: fix brace layout, per David.  Reduce indentation]
Link: http://lkml.kernel.org/r/20190122154407.18417-1-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Hildenbrand <david@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>

psi: fix aggregation idle shut-off

psi has provisions to shut off the periodic aggregation worker when
there is a period of no task activity - and thus no data that needs
aggregating.  However, while developing psi monitoring, Suren noticed
that the aggregation clock currently won't stay shut off for good.

Debugging this revealed a flaw in the idle design: an aggregation run
will see no task activity and decide to go to sleep; shortly thereafter,
the kworker thread that executed the aggregation will go idle and cause
a scheduling change, during which the psi callback will kick the
!pending worker again.  This will ping-pong forever, and is equivalent
to having no shut-off logic at all (but with more code!)

Fix this by exempting aggregation workers from psi's clock waking logic
when the state change is them going to sleep.  To do this, tag workers
with the last work function they executed, and if in psi we see a worker
going to sleep after aggregating psi data, we will not reschedule the
aggregation work item.

What if the worker is also executing other items before or after?

Any psi state times that were incurred by work items preceding the
aggregation work will have been collected from the per-cpu buckets
during the aggregation itself.  If there are work items following the
aggregation work, the worker's last_func tag will be overwritten and the
aggregator will be kept alive to process this genuine new activity.

If the aggregation work is the last thing the worker does, and we decide
to go idle, the brief period of non-idle time incurred between the
aggregation run and the kworker's dequeue will be stranded in the
per-cpu buckets until the clock is woken by later activity.  But that
should not be a problem.  The buckets can hold 4s worth of time, and
future activity will wake the clock with a 2s delay, giving us 2s worth
of data we can leave behind when disabling aggregation.  If it takes a
worker more than two seconds to go idle after it finishes its last work
item, we likely have bigger problems in the system, and won't notice one
sample that was averaged with a bogus per-CPU weight.

Link: http://lkml.kernel.org/r/20190116193501.1910-1-hannes@cmpxchg.org
Fixes: eb414681d5a0 ("psi: pressure stall information for CPU, memory, and IO")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm, memory_hotplug: test_pages_in_a_zone do not pass the end of zone

If memory end is not aligned with the sparse memory section boundary,
the mapping of such a section is only partly initialized.  This may lead
to VM_BUG_ON due to uninitialized struct pages access from
test_pages_in_a_zone() function triggered by memory_hotplug sysfs
handlers.

Here are the the panic examples:
 CONFIG_DEBUG_VM_PGFLAGS=y
 kernel parameter mem=2050M
 --------------------------
 page:000003d082008000 is uninitialized and poisoned
 page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p))
 Call Trace:
   test_pages_in_a_zone+0xde/0x160
   show_valid_zones+0x5c/0x190
   dev_attr_show+0x34/0x70
   sysfs_kf_seq_show+0xc8/0x148
   seq_read+0x204/0x480
   __vfs_read+0x32/0x178
   vfs_read+0x82/0x138
   ksys_read+0x5a/0xb0
   system_call+0xdc/0x2d8
 Last Breaking-Event-Address:
   test_pages_in_a_zone+0xde/0x160
 Kernel panic - not syncing: Fatal exception: panic_on_oops

Fix this by checking whether the pfn to check is within the zone.

[mhocko@suse.com: separated this change from http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@linux.ibm.com]
Link: http://lkml.kernel.org/r/20190128144506.15603-3-mhocko@kernel.org
[mhocko@suse.com: separated this change from
http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@linux.ibm.com]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Tested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm, memory_hotplug: is_mem_section_removable do not pass the end of a zone

Patch series "mm, memory_hotplug: fix uninitialized pages fallouts", v2.

Mikhail Zaslonko has posted fixes for the two bugs quite some time ago
[1].  I have pushed back on those fixes because I believed that it is
much better to plug the problem at the initialization time rather than
play whack-a-mole all over the hotplug code and find all the places
which expect the full memory section to be initialized.

We have ended up with commit 2830bf6f05fb ("mm, memory_hotplug:
initialize struct pages for the full memory section") merged and cause a
regression [2][3].  The reason is that there might be memory layouts
when two NUMA nodes share the same memory section so the merged fix is
simply incorrect.

In order to plug this hole we really have to be zone range aware in
those handlers.  I have split up the original patch into two.  One is
unchanged (patch 2) and I took a different approach for `removable'
crash.

[1] http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@linux.ibm.com
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1666948
[3] http://lkml.kernel.org/r/20190125163938.GA20411@dhcp22.suse.cz

This patch (of 2):

Mikhail has reported the following VM_BUG_ON triggered when reading sysfs
removable state of a memory block:

 page:000003d08300c000 is uninitialized and poisoned
 page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p))
 Call Trace:
   is_mem_section_removable+0xb4/0x190
   show_mem_removable+0x9a/0xd8
   dev_attr_show+0x34/0x70
   sysfs_kf_seq_show+0xc8/0x148
   seq_read+0x204/0x480
   __vfs_read+0x32/0x178
   vfs_read+0x82/0x138
   ksys_read+0x5a/0xb0
   system_call+0xdc/0x2d8
 Last Breaking-Event-Address:
   is_mem_section_removable+0xb4/0x190
 Kernel panic - not syncing: Fatal exception: panic_on_oops

The reason is that the memory block spans the zone boundary and we are
stumbling over an unitialized struct page.  Fix this by enforcing zone
range in is_mem_section_removable so that we never run away from a zone.

Link: http://lkml.kernel.org/r/20190128144506.15603-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Debugged-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Tested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

oom, oom_reaper: do not enqueue same task twice

Arkadiusz reported that enabling memcg's group oom killing causes
strange memcg statistics where there is no task in a memcg despite the
number of tasks in that memcg is not 0.  It turned out that there is a
bug in wake_oom_reaper() which allows enqueuing same task twice which
makes impossible to decrease the number of tasks in that memcg due to a
refcount leak.

This bug existed since the OOM reaper became invokable from
task_will_free_mem(current) path in out_of_memory() in Linux 4.7,

  T1@P1     |T2@P1     |T3@P1     |OOM reaper
  ----------+----------+----------+------------
                                   # Processing an OOM victim in a different memcg domain.
                        try_charge()
                          mem_cgroup_out_of_memory()
                            mutex_lock(&oom_lock)
             try_charge()
               mem_cgroup_out_of_memory()
                 mutex_lock(&oom_lock)
  try_charge()
    mem_cgroup_out_of_memory()
      mutex_lock(&oom_lock)
                            out_of_memory()
                              oom_kill_process(P1)
                                do_send_sig_info(SIGKILL, @P1)
                                mark_oom_victim(T1@P1)
                                wake_oom_reaper(T1@P1) # T1@P1 is enqueued.
                            mutex_unlock(&oom_lock)
                 out_of_memory()
                   mark_oom_victim(T2@P1)
                   wake_oom_reaper(T2@P1) # T2@P1 is enqueued.
                 mutex_unlock(&oom_lock)
      out_of_memory()
        mark_oom_victim(T1@P1)
        wake_oom_reaper(T1@P1) # T1@P1 is enqueued again due to oom_reaper_list == T2@P1 && T1@P1->oom_reaper_list == NULL.
      mutex_unlock(&oom_lock)
                                   # Completed processing an OOM victim in a different memcg domain.
                                   spin_lock(&oom_reaper_lock)
                                   # T1P1 is dequeued.
                                   spin_unlock(&oom_reaper_lock)

but memcg's group oom killing made it easier to trigger this bug by
calling wake_oom_reaper() on the same task from one out_of_memory()
request.

Fix this bug using an approach used by commit 855b018325737f76 ("oom,
oom_reaper: disable oom_reaper for oom_kill_allocating_task").  As a
side effect of this patch, this patch also avoids enqueuing multiple
threads sharing memory via task_will_free_mem(current) path.

Link: http://lkml.kernel.org/r/e865a044-2c10-9858-f4ef-254bc71d6cc2@i-love.sakura.ne.jp
Link: http://lkml.kernel.org/r/5ee34fc6-1485-34f8-8790-903ddabaa809@i-love.sakura.ne.jp
Fixes: af8e15cc85a25315 ("oom, oom_reaper: do not enqueue task if it is on the oom_reaper_list head")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: Arkadiusz Miskiewicz <arekm@maven.pl>
Tested-by: Arkadiusz Miskiewicz <arekm@maven.pl>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Aleksa Sarai <asarai@suse.de>
Cc: Jay Kamat <jgkamat@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: migrate: make buffer_migrate_page_norefs() actually succeed

Currently, buffer_migrate_page_norefs() was constantly failing because
buffer_migrate_lock_buffers() grabbed reference on each buffer.  In
fact, there's no reason for buffer_migrate_lock_buffers() to grab any
buffer references as the page is locked during all our operation and
thus nobody can reclaim buffers from the page.

So remove grabbing of buffer references which also makes
buffer_migrate_page_norefs() succeed.

Link: http://lkml.kernel.org/r/20190116131217.7226-1-jack@suse.cz
Fixes: 89cb0888ca14 "mm: migrate: provide buffer_migrate_page_norefs()"
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/exit.c: release ptraced tasks before zap_pid_ns_processes

Currently, exit_ptrace() adds all ptraced tasks in a dead list, then
zap_pid_ns_processes() waits on all tasks in a current pidns, and only
then are tasks from the dead list released.

zap_pid_ns_processes() can get stuck on waiting tasks from the dead
list.  In this case, we will have one unkillable process with one or
more dead children.

Thanks to Oleg for the advice to release tasks in find_child_reaper().

Link: http://lkml.kernel.org/r/20190110175200.12442-1-avagin@gmail.com
Fixes: 7c8bd2322c7f ("exit: ptrace: shift "reap dead" code from exit_ptrace() to forget_original_parent()")
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

x86_64: increase stack size for KASAN_EXTRA

If the kernel is configured with KASAN_EXTRA, the stack size is
increasted significantly because this option sets "-fstack-reuse" to
"none" in GCC [1].  As a result, it triggers stack overrun quite often
with 32k stack size compiled using GCC 8.  For example, this reproducer

  https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/syscalls/madvise/madvise06.c

triggers a "corrupted stack end detected inside scheduler" very reliably
with CONFIG_SCHED_STACK_END_CHECK enabled.

There are just too many functions that could have a large stack with
KASAN_EXTRA due to large local variables that have been called over and
over again without being able to reuse the stacks.  Some noticiable ones
are

  size
  7648 shrink_page_list
  3584 xfs_rmap_convert
  3312 migrate_page_move_mapping
  3312 dev_ethtool
  3200 migrate_misplaced_transhuge_page
  3168 copy_process

There are other 49 functions are over 2k in size while compiling kernel
with "-Wframe-larger-than=" even with a related minimal config on this
machine.  Hence, it is too much work to change Makefiles for each object
to compile without "-fsanitize-address-use-after-scope" individually.

[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715#c23

Although there is a patch in GCC 9 to help the situation, GCC 9 probably
won't be released in a few months and then it probably take another
6-month to 1-year for all major distros to include it as a default.
Hence, the stack usage with KASAN_EXTRA can be revisited again in 2020
when GCC 9 is everywhere.  Until then, this patch will help users avoid
stack overrun.

This has already been fixed for arm64 for the same reason via
6e8830674ea ("arm64: kasan: Increase stack size for KASAN_EXTRA").

Link: http://lkml.kernel.org/r/20190109215209.2903-1-cai@lca.pw
Signed-off-by: Qian Cai <cai@lca.pw>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/hugetlb.c: teach follow_hugetlb_page() to handle FOLL_NOWAIT

hugetlb needs the same fix as faultin_nopage (which was applied in
commit 96312e61282a ("mm/gup.c: teach get_user_pages_unlocked to handle
FOLL_NOWAIT")) or KVM hangs because it thinks the mmap_sem was already
released by hugetlb_fault() if it returned VM_FAULT_RETRY, but it wasn't
in the FOLL_NOWAIT case.

Link: http://lkml.kernel.org/r/20190109020203.26669-2-aarcange@redhat.com
Fixes: ce53053ce378 ("kvm: switch get_user_page_nowait() to get_user_pages_unlocked()")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Reported-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch: unexport asm/shmparam.h for all architectures

Most architectures do not export shmparam.h to user-space.

  $ find arch -name shmparam.h  | sort
  arch/alpha/include/asm/shmparam.h
  arch/arc/include/asm/shmparam.h
  arch/arm64/include/asm/shmparam.h
  arch/arm/include/asm/shmparam.h
  arch/csky/include/asm/shmparam.h
  arch/ia64/include/asm/shmparam.h
  arch/mips/include/asm/shmparam.h
  arch/nds32/include/asm/shmparam.h
  arch/nios2/include/asm/shmparam.h
  arch/parisc/include/asm/shmparam.h
  arch/powerpc/include/asm/shmparam.h
  arch/s390/include/asm/shmparam.h
  arch/sh/include/asm/shmparam.h
  arch/sparc/include/asm/shmparam.h
  arch/x86/include/asm/shmparam.h
  arch/xtensa/include/asm/shmparam.h

Strangely, some users of the asm-generic wrapper export shmparam.h

  $ git grep 'generic-y += shmparam.h'
  arch/c6x/include/uapi/asm/Kbuild:generic-y += shmparam.h
  arch/h8300/include/uapi/asm/Kbuild:generic-y += shmparam.h
  arch/hexagon/include/uapi/asm/Kbuild:generic-y += shmparam.h
  arch/m68k/include/uapi/asm/Kbuild:generic-y += shmparam.h
  arch/microblaze/include/uapi/asm/Kbuild:generic-y += shmparam.h
  arch/openrisc/include/uapi/asm/Kbuild:generic-y += shmparam.h
  arch/riscv/include/asm/Kbuild:generic-y += shmparam.h
  arch/unicore32/include/uapi/asm/Kbuild:generic-y += shmparam.h

The newly added riscv correctly creates the asm-generic wrapper
in the kernel space, but the others (c6x, h8300, hexagon, m68k,
microblaze, openrisc, unicore32) create the one in the uapi directory.

Digging into the git history, now I guess fcc8487d477a ("uapi:
export all headers under uapi directories") was the misconversion.
Prior to that commit, no architecture exported to shmparam.h
As its commit description said, that commit exported shmparam.h
for c6x, h8300, hexagon, m68k, openrisc, unicore32.

83f0124ad81e ("microblaze: remove asm-generic wrapper headers")
accidentally exported shmparam.h for microblaze.

This commit unexports shmparam.h for those architectures.

There is no more reason to export include/uapi/asm-generic/shmparam.h,
so it has been moved to include/asm-generic/shmparam.h

Link: http://lkml.kernel.org/r/1546904307-11124-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Stafford Horne <shorne@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Mark Salter <msalter@redhat.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Vincent Chen <deanbo422@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

proc: fix /proc/net/* after setns(2)

/proc entries under /proc/net/* can't be cached into dcache because
setns(2) can change current net namespace.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: avoid vim miscolorization]
[adobriyan@gmail.com: write test, add dummy ->d_revalidate hook: necessary if /proc/net/* is pinned at setns time]
Link: http://lkml.kernel.org/r/20190108192350.GA12034@avx2
Link: http://lkml.kernel.org/r/20190107162336.GA9239@avx2
Fixes: 1da4d377f943fe4194ffb9fb9c26cc58fad4dd24 ("proc: revalidate misc dentries")
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reported-by: Mateusz Stępień <mateusz.stepien@netrounds.com>
Reported-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm, memory_hotplug: don't bail out in do_migrate_range() prematurely

do_migrate_range() takes a memory range and tries to isolate the pages
to put them into a list.  This list will be later on used in
migrate_pages() to know the pages we need to migrate.

Currently, if we fail to isolate a single page, we put all already
isolated pages back to their LRU and we bail out from the function.
This is quite suboptimal, as this will force us to start over again
because scan_movable_pages will give us the same range.  If there is no
chance that we can isolate that page, we will loop here forever.

Issue debugged in [1] has proved that.  During the debugging of that
issue, it was noticed that if do_migrate_ranges() fails to isolate a
single page, we will just discard the work we have done so far and bail
out, which means that scan_movable_pages() will find again the same set
of pages.

Instead, we can just skip the error, keep isolating as much pages as
possible and then proceed with the call to migrate_pages().

This will allow us to do as much work as possible at once.

[1] https://lkml.org/lkml/2018/12/6/324

Michal said:

: I still think that this doesn't give us a whole picture.  Looping for
: ever is a bug.  Failing the isolation is quite possible and it should
: be a ephemeral condition (e.g.  a race with freeing the page or
: somebody else isolating the page for whatever reason).  And here comes
: the disadvantage of the current implementation.  We simply throw
: everything on the floor just because of a ephemeral condition.  The
: racy page_count check is quite dubious to prevent from that.

Link: http://lkml.kernel.org/r/20181211135312.27034-1-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dan Williams <dan.j.williams@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'for-linus' of git://git./linux/kernel/git/rdma/rdma

Pull rdma fixes from Jason Gunthorpe:
 "Still not much going on, the usual set of oops and driver fixes this
  time:

   - Fix two uapi breakage regressions in mlx5 drivers

   - Various oops fixes in hfi1, mlx4, umem, uverbs, and ipoib

   - A protocol bug fix for hfi1 preventing it from implementing the
     verbs API properly, and a compatability fix for EXEC STACK user
     programs

   - Fix missed refcounting in the 'advise_mr' patches merged this
     cycle.

   - Fix wrong use of the uABI in the hns SRQ patches merged this cycle"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  IB/uverbs: Fix OOPs in uverbs_user_mmap_disassociate
  IB/ipoib: Fix for use-after-free in ipoib_cm_tx_start
  IB/uverbs: Fix ioctl query port to consider device disassociation
  RDMA/mlx5: Fix flow creation on representors
  IB/uverbs: Fix OOPs upon device disassociation
  RDMA/umem: Add missing initialization of owning_mm
  RDMA/hns: Update the kernel header file of hns
  IB/mlx5: Fix how advise_mr() launches async work
  RDMA/device: Expose ib_device_try_get(()
  IB/hfi1: Add limit test for RC/UC send via loopback
  IB/hfi1: Remove overly conservative VM_EXEC flag check
  IB/{hfi1, qib}: Fix WC.byte_len calculation for UD_SEND_WITH_IMM
  IB/mlx4: Fix using wrong function to destroy sqp AHs under SRIOV
  RDMA/mlx5: Fix check for supported user flags when creating a QP

Merge tag 'iomap-5.0-fixes-1' of git://git./fs/xfs/xfs-linux

Pull iomap fixes from Darrick Wong:
 "A couple of iomap fixes to eliminate some memory corruption and hang
  problems that were reported:

   - fix page migration when using iomap for pagecache management

   - fix a use-after-free bug in the directio code"

* tag 'iomap-5.0-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: fix a use after free in iomap_dio_rw
  iomap: get/put the page in iomap_page_create/release()

Merge tag 'pm-5.0-rc5' of git://git./linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix a PM-runtime framework regression introduced by the recent
  switch-over of device autosuspend to hrtimers and a mistake in the
  "poll idle state" code introduced by a recent change in it.

  Specifics:

   - Since ktime_get() turns out to be problematic for device
     autosuspend in the PM-runtime framework, make it use
     ktime_get_mono_fast_ns() instead (Vincent Guittot).

   - Fix an initial value of a local variable in the "poll idle state"
     code that makes it behave not exactly as expected when all idle
     states except for the "polling" one are disabled (Doug Smythies)"

* tag 'pm-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpuidle: poll_state: Fix default time limit
  PM-runtime: Fix deadlock with ktime_get()

Merge tag 'acpi-5.0-rc5' of git://git./linux/kernel/git/rafael/linux-pm

Pull ACPI Kconfig fixes from Rafael Wysocki:
 "Prevent invalid configurations from being created (e.g. by randconfig)
  due to some ACPI-related Kconfig options' dependencies that are not
  specified directly (Sinan Kaya)"

* tag 'acpi-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  platform/x86: Fix unmet dependency warning for SAMSUNG_Q10
  platform/x86: Fix unmet dependency warning for ACPI_CMPC
  mfd: Fix unmet dependency warning for MFD_TPS68470