When executing the task exit testing case, perf gets stuck in an endless
loop this case and doesn't return back on Arm64 Juno board.

After digging into this issue, since Juno board has Arm's big.LITTLE
CPUs, thus the PMUs are not compatible between the big CPUs and little
CPUs.  This leads to a PMU event that cannot be enabled properly when
the traced task is migrated from one variant's CPU to another variant.
Finally, the test case runs into infinite loop for cannot read out any
event data after return from polling.

Eventually, we need to work out formal solution to allow PMU events can
be freely migrated from one CPU variant to another, but this is a
difficult task and a different topic.  This patch tries to fix the Perf
test case to avoid infinite loop, when the testing detects 1000 times
retrying for reading empty events, it will directly bail out and return
failure.  This allows the Perf tool can continue its other test cases.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20191011091942.29841-2-leo.yan@linaro.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When fail to mmap events in task exit case, it misses to set 'err' to
-1; thus the testing will not report failure for it.

This patch sets 'err' to -1 when fails to mmap events, thus Perf tool
can report correct result.

Fixes: d723a550 ("perf test: Add test case for checking number of EXIT events")
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20191011091942.29841-1-leo.yan@linaro.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

In the earlier fix for the memory overrun of id arrays I managed to typo
the wrong event in the fix.

Of course we need to close the current event in the loop, not the
original failing event.

The same test case as in the original patch still passes.

Fixes: 7834fa94 ("perf evlist: Fix access of freed id arrays")
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191011182140.8353-2-andi@firstfloor.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

My earlier patch to just enable --reltime with --time was a little too
optimistic.  The --time parsing would accept absolute time, which is
very confusing to the user.

Support relative time in --time parsing too. This only works with recent
perf record that records the first sample time. Otherwise we error out.

Fixes: 3714437d ("perf script: Allow --time with --reltime")
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191011182140.8353-1-andi@firstfloor.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

By using "make TCMALLOC=1" you can enable perf to be build for usage
with libtcmalloc.so (gperftools).

Get heap profile (tools/perf directory):

  $ <install gperftools>
  $ make TCMALLOC=1 DEBUG=1
  $ HEAPPROFILE=/tmp/heapprof ./perf ...
  $ pprof ./perf /tmp/heapprof.000*
  (pprof) top
  Total: 2335.5 MB
    1735.1  74.3%  74.3%   1735.1  74.3% memdup
     402.0  17.2%  91.5%    402.0  17.2% zalloc
     140.2   6.0%  97.5%    145.8   6.2% map__new
      33.6   1.4%  98.9%     33.6   1.4% symbol__new
      12.4   0.5%  99.5%     12.4   0.5% alloc_event
       6.2   0.3%  99.7%      6.2   0.3% nsinfo__new
       5.5   0.2% 100.0%      5.5   0.2% nsinfo__copy
       0.3   0.0% 100.0%      0.3   0.0% dso__new
       0.1   0.0% 100.0%      0.1   0.0% do_read_string
       0.0   0.0% 100.0%      0.0   0.0% __GI__IO_file_doallocate

See callstack:
  $ pprof --pdf ./perf /tmp/heapprof.00* > callstack.pdf
  $ pprof --web ./perf /tmp/heapprof.00*

Committer testing:

Install gperftools, on fedora:

  # dnf install gperftools-devel

Then build:

 $ make TCMALLOC=1 DEBUG=1 -C tools/perf O=/tmp/build/perf install-bin

Verify that it linked against the right library:

  $ ldd ~/bin/perf | grep tcma
	libtcmalloc.so.4 => /lib64/libtcmalloc.so.4 (0x00007fb2953a7000)
  $

Run 'perf trace' system wide for 1 minute:

  # HEAPPROFILE=/tmp/heapprof perf trace -a sleep 1m
  <SNIP>
   59985.524 ( 0.006 ms): Web Content/20354 recvmsg(fd: 9<socket:[1762817]>, msg: 0x7ffee5fdafb0) = -1 EAGAIN (Resource temporarily unavailable)
   59985.536 ( 0.005 ms): Web Content/20354 recvmsg(fd: 9<socket:[1762817]>, msg: 0x7ffee5fdafc0) = -1 EAGAIN (Resource temporarily unavailable)
   59981.956 (10.143 ms): SCTP timer/21716  ... [continued]: select())                            = 0 (Timeout)
   59985.549 (         ): Web Content/20354 poll(ufds: 0x7f1df38af180, nfds: 3, timeout_msecs: 4294967295) ...
       0.926 (59999.481 ms): sleep/29764  ... [continued]: nanosleep())                           = 0
   59992.133 (         ): SCTP timer/21716 select(tvp: 0x7ff5bf7fee80)                            ...
   60000.477 ( 0.009 ms): sleep/29764 close(fd: 1)                                                = 0
   60000.493 ( 0.005 ms): sleep/29764 close(fd: 2)                                                = 0
   60000.514 (         ): sleep/29764 exit_group()                                                = ?
  Dumping heap profile to /tmp/heapprof.0001.heap (Exiting, 3 MB in use)
[root@quaco ~]#

Install pprof:

  # dnf install pprof

And run it:

  # pprof ~/bin/perf /tmp/heapprof.0001.heap
  Using local file /root/bin/perf.
  Using local file /tmp/heapprof.0001.heap.
  Welcome to pprof!  For help, type 'help'.
  (pprof) top
  Total: 4.0 MB
       1.7  42.0%  42.0%      2.2  54.1% map__new
       0.9  23.3%  65.3%      0.9  23.3% zalloc
       0.5  11.4%  76.7%      0.5  11.4% dso__new
       0.2   5.6%  82.3%      0.3   8.5% trace__sys_enter
       0.2   4.9%  87.2%      0.2   4.9% __GI___strdup
       0.2   3.8%  91.0%      0.2   3.8% new_term
       0.1   2.2%  93.2%      0.4  10.1% __perf_pmu__new_alias
       0.0   1.0%  94.3%      0.0   1.2% event_read_fields
       0.0   0.8%  95.1%      0.0   0.8% nsinfo__new
       0.0   0.7%  95.8%      0.1   3.2% trace__read_syscall_info
  (pprof)
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20191013151427.11941-2-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-core-for-mingo-5.5-20191011' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

perf trace:

  Arnaldo Carvalho de Melo:

  - Reuse the strace-like syscall_arg_fmt->scnprintf() beautification routines
    (convert integer arguments into strings, like open flags, etc) in tracepoint
    arguments.

    For now the type based scnprintf routines (pid_t, umode_t, etc) and the
    ones based in well known arg name based ("fd", etc) gets associated with
    tracepoint args of that type.

    A tracepoint only arg, "msr", for the msr:{write,read}_msr gets added as
    an initial step.

  - Introduce syscall_arg_fmt->strtoul() methods to be the reverse operation
    of ->scnprintf(), i.e. to go from a string to an integer.

  - Implement --filter, just like in 'perf record', that affects the tracepoint
    events specied thus far in the command line, use the ->strtoul() methods
    to allow strings in tables associated with beautifiers to the integers
    the in-kernel tracepoint (eBPF later) filters expect, e.g.:

     # perf trace --max-events 1 -e sched:*ipi --filter="cpu==1 || cpu==2"
      0.000 as/24630 sched:sched_wake_idle_without_ipi(cpu: 1)
     #

     # perf trace --max-events 1 --max-stack=32 -e msr:* --filter="msr==IA32_TSC_DEADLINE"
      207.000 cc1/19963 msr:write_msr(msr: IA32_TSC_DEADLINE, val: 5442316760822)
                                        do_trace_write_msr ([kernel.kallsyms])
                                        do_trace_write_msr ([kernel.kallsyms])
                                        lapic_next_deadline ([kernel.kallsyms])
                                        clockevents_program_event ([kernel.kallsyms])
                                        hrtimer_interrupt ([kernel.kallsyms])
                                        smp_apic_timer_interrupt ([kernel.kallsyms])
                                        apic_timer_interrupt ([kernel.kallsyms])
                                        [0x6ff66c] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x7047c3] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x707708] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        execute_one_pass (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x4f3d37] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x4f3d49] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        execute_pass_list (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        cgraph_node::expand (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x2625b4] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        symbol_table::finalize_compilation_unit (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x5ae8b9] (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        toplev::main (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        main (/usr/lib/gcc-cross/alpha-linux-gnu/8/cc1)
                                        [0x26b6a] (/usr/lib/x86_64-linux-gnu/libc-2.29.so)
     #
     # perf trace --max-events 8 -e msr:* --filter="msr==IA32_SPEC_CTRL"
         0.000 :13281/13281 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
         0.063 migration/3/25 msr:write_msr(msr: IA32_SPEC_CTRL)
         0.217 kworker/u16:1-/4826 msr:write_msr(msr: IA32_SPEC_CTRL)
         0.687 rcu_sched/11 msr:write_msr(msr: IA32_SPEC_CTRL)
         0.696 :13280/13280 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
         0.305 :13281/13281 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
         0.355 :13274/13274 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
         2.743 kworker/u16:0-/6711 msr:write_msr(msr: IA32_SPEC_CTRL)
     #
     # perf trace --max-events 8 --cpu 1 -e msr:* --filter="msr!=IA32_SPEC_CTRL && msr!=IA32_TSC_DEADLINE && msr != FS_BASE"
           0.000 mtr-packet/30819 msr:write_msr(msr: 0x830, val: 68719479037)
           0.096 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
         238.925 mtr-packet/30819 msr:write_msr(msr: 0x830, val: 8589936893)
         511.010 :0/0 msr:write_msr(msr: 0x830, val: 68719479037)
        1005.052 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
        1235.131 CPU 0/KVM/3750 msr:write_msr(msr: 0x830, val: 4294969595)
        1235.195 CPU 0/KVM/3750 msr:read_msr(msr: IA32_SYSENTER_ESP, val: -2199023037952)
        1235.201 CPU 0/KVM/3750 msr:read_msr(msr: IA32_APICBASE, val: 4276096000)
     #

  - Default to not using libtraceevent and its plugins for beautifying
    tracepoint arguments, since now we're reusing the strace-like beatufiers.
    Use --libtraceevent_print (using just --libtrace is unambiguous and can
    be used as a short hand) to go back to those beautifiers.

    This will help in the transition, as can be seen in some of the sched tracepoints
    that still need some work in the libbeauty based mode:

    # trace --no-inherit -e msr:*,*sleep,sched:* sleep 1
         0.000 (         ): sched:sched_waking(comm: "trace", pid: 3319 (trace), prio: 120, success: 1)
         0.006 (         ): sched:sched_wakeup(comm: "trace", pid: 3319 (trace), prio: 120, success: 1)
         0.348 (         ): sched:sched_process_exec(filename: 140212596720100, pid: 3319 (sleep), old_pid: 3319 (sleep))
         0.490 (         ): msr:write_msr(msr: FS_BASE, val: 139631189321088)
         0.670 (         ): nanosleep(rqtp: 0x7ffc52c23bc0)                                    ...
         0.674 (         ): sched:sched_stat_runtime(comm: "sleep", pid: 3319 (sleep), runtime: 659259, vruntime: 78942418342)
         0.675 (         ): sched:sched_switch(prev_comm: "sleep", prev_pid: 3319 (sleep), prev_prio: 120, prev_state: 1, next_comm: "swapper/0", next_prio: 120)
      1001.059 (         ): sched:sched_waking(comm: "sleep", pid: 3319 (sleep), prio: 120, success: 1)
      1001.098 (         ): sched:sched_wakeup(comm: "sleep", pid: 3319 (sleep), prio: 120, success: 1)
         0.670 (1000.504 ms):  ... [continued]: nanosleep())                                        = 0
      1001.456 (         ): sched:sched_process_exit(comm: "sleep", pid: 3319 (sleep), prio: 120)
    # trace --libtrace --no-inherit -e msr:*,*sleep,sched:* sleep 1
    # trace --libtrace --no-inherit -e msr:*,*sleep,sched:* sleep 1
         0.000 (         ): sched:sched_waking(comm=trace pid=3323 prio=120 target_cpu=000)
         0.007 (         ): sched:sched_wakeup(comm=trace pid=3323 prio=120 target_cpu=000)
         0.382 (         ): sched:sched_process_exec(filename=/usr/bin/sleep pid=3323 old_pid=3323)
         0.525 (         ): msr:write_msr(c0000100, value 7f5d508a0580)
         0.713 (         ): nanosleep(rqtp: 0x7fff487fb4a0)                                    ...
         0.717 (         ): sched:sched_stat_runtime(comm=sleep pid=3323 runtime=617722 [ns] vruntime=78957731636 [ns])
         0.719 (         ): sched:sched_switch(prev_comm=sleep prev_pid=3323 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120)
      1001.117 (         ): sched:sched_waking(comm=sleep pid=3323 prio=120 target_cpu=000)
      1001.157 (         ): sched:sched_wakeup(comm=sleep pid=3323 prio=120 target_cpu=000)
         0.713 (1000.522 ms):  ... [continued]: nanosleep())                                        = 0
      1001.538 (         ): sched:sched_process_exit(comm=sleep pid=3323 prio=120)
    #

  - Make -v (verbose) mode be honoured for .perfconfig based trace.add_events,
    to help in diagnosing problems with building eBPF events (-e source.c).

  - When using eBPF syscall payload augmentation do not show strace-like
    syscalls when all the user specified was some tracepoint event, bringing
    the behaviour in line with that of when not using eBPF augmentation.

Intel PT:

  exported-sql-viewer GUI:

  Adrian Hunter:

  - Add LookupModel, HBoxLayout, VBoxLayout, global time range calculations
    so as to add a time chart by CPU.

perf script:

  Andi Kleen:

  - Allow --time (to specify a time span of interest) with --reltime

perf diff:

  Jin Yao:

  - Report noise for cycles diff, i.e. a histogram + stddev.
    (timestamps relative to start).

perf annotate:

  Arnaldo Carvalho de Melo:

  - Initialize env->cpuid when running in live mode (perf top), as it
    is used in some of the per arch annotation init routines.

samples bpf:

  Björn Töpel:

  - Fixup fallout of using tools/perf/perf-sys. from outside tools/perf.

Core:

  Ian Rogers:

  - Avoid 'sample_reg_masks' being const + weak, as this breaks with some
    compilers that constant-propagate from the weak symbol.

libperf:

  - First part of moving the perf_mmap class from tools/perf to libperf.

  - Propagate CFLAGS to libperf from the tools/perf Makefile.

Vendor events:

  John Garry:

  - Add entry in MAINTAINERS with reviewers for the for perf tool arm64
    pmu-events files.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Pull tracing fixes from Steven Rostedt:
 "A few tracing fixes:

   - Remove lockdown from tracefs itself and moved it to the trace
     directory. Have the open functions there do the lockdown checks.

   - Fix a few races with opening an instance file and the instance
     being deleted (Discovered during the lockdown updates). Kept
     separate from the clean up code such that they can be backported to
     stable easier.

   - Clean up and consolidated the checks done when opening a trace
     file, as there were multiple checks that need to be done, and it
     did not make sense having them done in each open instance.

   - Fix a regression in the record mcount code.

   - Small hw_lat detector tracer fixes.

   - A trace_pipe read fix due to not initializing trace_seq"

* tag 'trace-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Initialize iter->seq after zeroing in tracing_read_pipe()
  tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency
  tracing/hwlat: Report total time spent in all NMIs during the sample
  recordmcount: Fix nop_mcount() function
  tracing: Do not create tracefs files if tracefs lockdown is in effect
  tracing: Add locked_down checks to the open calls of files created for tracefs
  tracing: Add tracing_check_open_get_tr()
  tracing: Have trace events system open call tracing_open_generic_tr()
  tracing: Get trace_array reference for available_tracers files
  ftrace: Get a reference counter for the trace_array on filter files
  tracefs: Revert ccbd54ff ("tracefs: Restrict tracefs when the kernel is locked down")

Merge tag 'hwmon-for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:

 - Update/fix inspur-ipsps1 and k10temp Documentation

 - Fix nct7904 driver

 - Fix HWMON_P_MIN_ALARM mask in hwmon core

* tag 'hwmon-for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: docs: Extend inspur-ipsps1 title underline
  hwmon: (nct7904) Add array fan_alarm and vsen_alarm to store the alarms in nct7904_data struct.
  docs: hwmon: Include 'inspur-ipsps1.rst' into docs
  hwmon: Fix HWMON_P_MIN_ALARM mask
  hwmon: (k10temp) Update documentation and add temp2_input info
  hwmon: (nct7904) Fix the incorrect value of vsen_mask in nct7904_data struct

Pull MTD fixes from Richard Weinberger:
 "Two fixes for MTD:

   - spi-nor: Fix for a regression in write_sr()

   - rawnand: Regression fix for the au1550nd driver"

* tag 'fixes-for-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux:
  mtd: rawnand: au1550nd: Fix au_read_buf16() prototype
  mtd: spi-nor: Fix direction of the write_sr() transfer

Pull io_uring fix from Jens Axboe:
 "Single small fix for a regression in the sequence logic for linked
  commands"

* tag 'for-linus-20191012' of git://git.kernel.dk/linux-block:
  io_uring: fix sequence logic for timeout requests

A customer reported the following softlockup:

[899688.160002] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [test.sh:16464]
[899688.160002] CPU: 0 PID: 16464 Comm: test.sh Not tainted 4.12.14-6.23-azure #1 SLE12-SP4
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] Kernel panic - not syncing: softlockup: hung tasks
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] RSP: 0018:ffffa86784d4fde8 EFLAGS: 00000257 ORIG_RAX: ffffffffffffff12
[899688.160002] RAX: ffffffff970fea00 RBX: 0000000000000001 RCX: 0000000000000000
[899688.160002] RDX: ffffffff00000001 RSI: 0000000000000080 RDI: ffffffff970fea00
[899688.160002] RBP: ffffffffffffffff R08: ffffffffffffffff R09: 0000000000000000
[899688.160002] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8b59014720d8
[899688.160002] R13: ffff8b59014720c0 R14: ffff8b5901471090 R15: ffff8b5901470000
[899688.160002]  tracing_read_pipe+0x336/0x3c0
[899688.160002]  __vfs_read+0x26/0x140
[899688.160002]  vfs_read+0x87/0x130
[899688.160002]  SyS_read+0x42/0x90
[899688.160002]  do_syscall_64+0x74/0x160

It caught the process in the middle of trace_access_unlock(). There is
no loop. So, it must be looping in the caller tracing_read_pipe()
via the "waitagain" label.

Crashdump analyze uncovered that iter->seq was completely zeroed
at this point, including iter->seq.seq.size. It means that
print_trace_line() was never able to print anything and
there was no forward progress.

The culprit seems to be in the code:

	/* reset all but tr, trace, and overruns */
	memset(&iter->seq, 0,
	       sizeof(struct trace_iterator) -
	       offsetof(struct trace_iterator, seq));

It was added by the commit 53d0aa77 ("ftrace:
add logic to record overruns"). It was v2.6.27-rc1.
It was the time when iter->seq looked like:

     struct trace_seq {
	unsigned char		buffer[PAGE_SIZE];
	unsigned int		len;
     };

There was no "size" variable and zeroing was perfectly fine.

The solution is to reinitialize the structure after or without
zeroing.

Link: http://lkml.kernel.org/r/20191011142134.11997-1-pmladek@suse.comSigned-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

max_latency is intended to record the maximum ever observed hardware
latency, which may occur in either part of the loop (inner/outer). So
we need to also consider the outer-loop sample when updating
max_latency.

Link: http://lkml.kernel.org/r/157073345463.17189.18124025522664682811.stgit@srivatsa-ubuntu

Fixes: e7c15cd8 ("tracing: Added hardware latency tracer")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

nmi_total_ts is supposed to record the total time spent in *all* NMIs
that occur on the given CPU during the (active portion of the)
sampling window. However, the code seems to be overwriting this
variable for each NMI, thereby only recording the time spent in the
most recent NMI. Fix it by accumulating the duration instead.

Link: http://lkml.kernel.org/r/157073343544.17189.13911783866738671133.stgit@srivatsa-ubuntu

Fixes: 7b2c8625 ("tracing: Add NMI tracing in hwlat detector")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

The removal of the longjmp code in recordmcount.c mistakenly made the return
of make_nop() being negative an exit of nop_mcount(). It should not exit the
routine, but instead just not process that part of the code. By exiting with
an error code, it would cause the update of recordmcount to fail some files
which would fail the build if ftrace function tracing was enabled.

Link: http://lkml.kernel.org/r/20191009110538.5909fec6@gandalf.local.homeReported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Fixes: 3f1df120 ("recordmcount: Rewrite error/success handling")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

If on boot up, lockdown is activated for tracefs, don't even bother creating
the files. This can also prevent instances from being created if lockdown is
in effect.

Link: http://lkml.kernel.org/r/CAHk-=whC6Ji=fWnjh2+eS4b15TnbsS4VPVtvBOwCy1jjEG_JHQ@mail.gmail.comSuggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Added various checks on open tracefs calls to see if tracefs is in lockdown
mode, and if so, to return -EPERM.

Note, the event format files (which are basically standard on all machines)
as well as the enabled_functions file (which shows what is currently being
traced) are not lockde down. Perhaps they should be, but it seems counter
intuitive to lockdown information to help you know if the system has been
modified.

Link: http://lkml.kernel.org/r/CAHk-=wj7fGPKUspr579Cii-w_y60PtRaiDgKuxVtBAMK0VNNkA@mail.gmail.comSuggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Currently, most files in the tracefs directory test if tracing_disabled is
set. If so, it should return -ENODEV. The tracing_disabled is called when
tracing is found to be broken. Originally it was done in case the ring
buffer was found to be corrupted, and we wanted to prevent reading it from
crashing the kernel. But it's also called if a tracing selftest fails on
boot. It's a one way switch. That is, once it is triggered, tracing is
disabled until reboot.

As most tracefs files can also be used by instances in the tracefs
directory, they need to be carefully done. Each instance has a trace_array
associated to it, and when the instance is removed, the trace_array is
freed. But if an instance is opened with a reference to the trace_array,
then it requires looking up the trace_array to get its ref counter (as there
could be a race with it being deleted and the open itself). Once it is
found, a reference is added to prevent the instance from being removed (and
the trace_array associated with it freed).

Combine the two checks (tracing_disabled and trace_array_get()) into a
single helper function. This will also make it easier to add lockdown to
tracefs later.

Link: http://lkml.kernel.org/r/20191011135458.7399da44@gandalf.local.homeSigned-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Instead of having the trace events system open call open code the taking of
the trace_array descriptor (with trace_array_get()) and then calling
trace_open_generic(), have it use the tracing_open_generic_tr() that does
the combination of the two. This requires making tracing_open_generic_tr()
global.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

As instances may have different tracers available, we need to look at the
trace_array descriptor that shows the list of the available tracers for the
instance. But there's a race between opening the file and an admin
deleting the instance. The trace_array_get() needs to be called before
accessing the trace_array.

Cc: stable@vger.kernel.org
Fixes: 607e2ea1 ("tracing: Set up infrastructure to allow tracers for instances")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

The ftrace set_ftrace_filter and set_ftrace_notrace files are specific for
an instance now. They need to take a reference to the instance otherwise
there could be a race between accessing the files and deleting the instance.

It wasn't until the :mod: caching where these file operations started
referencing the trace_array directly.

Cc: stable@vger.kernel.org
Fixes: 673feb9d ("ftrace: Add :mod: caching infrastructure to trace_array")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Running the latest kernel through my "make instances" stress tests, I
triggered the following bug (with KASAN and kmemleak enabled):

mkdir invoked oom-killer:
gfp_mask=0x40cd0(GFP_KERNEL|__GFP_COMP|__GFP_RECLAIMABLE), order=0,
oom_score_adj=0
CPU: 1 PID: 2229 Comm: mkdir Not tainted 5.4.0-rc2-test #325
Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014
Call Trace:
 dump_stack+0x64/0x8c
 dump_header+0x43/0x3b7
 ? trace_hardirqs_on+0x48/0x4a
 oom_kill_process+0x68/0x2d5
 out_of_memory+0x2aa/0x2d0
 __alloc_pages_nodemask+0x96d/0xb67
 __alloc_pages_node+0x19/0x1e
 alloc_slab_page+0x17/0x45
 new_slab+0xd0/0x234
 ___slab_alloc.constprop.86+0x18f/0x336
 ? alloc_inode+0x2c/0x74
 ? irq_trace+0x12/0x1e
 ? tracer_hardirqs_off+0x1d/0xd7
 ? __slab_alloc.constprop.85+0x21/0x53
 __slab_alloc.constprop.85+0x31/0x53
 ? __slab_alloc.constprop.85+0x31/0x53
 ? alloc_inode+0x2c/0x74
 kmem_cache_alloc+0x50/0x179
 ? alloc_inode+0x2c/0x74
 alloc_inode+0x2c/0x74
 new_inode_pseudo+0xf/0x48
 new_inode+0x15/0x25
 tracefs_get_inode+0x23/0x7c
 ? lookup_one_len+0x54/0x6c
 tracefs_create_file+0x53/0x11d
 trace_create_file+0x15/0x33
 event_create_dir+0x2a3/0x34b
 __trace_add_new_event+0x1c/0x26
 event_trace_add_tracer+0x56/0x86
 trace_array_create+0x13e/0x1e1
 instance_mkdir+0x8/0x17
 tracefs_syscall_mkdir+0x39/0x50
 ? get_dname+0x31/0x31
 vfs_mkdir+0x78/0xa3
 do_mkdirat+0x71/0xb0
 sys_mkdir+0x19/0x1b
 do_fast_syscall_32+0xb0/0xed

I bisected this down to the addition of the proxy_ops into tracefs for
lockdown. It appears that the allocation of the proxy_ops and then freeing
it in the destroy_inode callback, is causing havoc with the memory system.
Reading the documentation about destroy_inode and talking with Linus about
this, this is buggy and wrong. When defining the destroy_inode() method, it
is expected that the destroy_inode() will also free the inode, and not just
the extra allocations done in the creation of the inode. The faulty commit
causes a memory leak of the inode data structure when they are deleted.

Instead of allocating the proxy_ops (and then having to free it) the checks
should be done by the open functions themselves, and not hack into the
tracefs directory. First revert the tracefs updates for locked_down and then
later we can add the locked_down checks in the kernel/trace files.

Link: http://lkml.kernel.org/r/20191011135458.7399da44@gandalf.local.home

Fixes: ccbd54ff ("tracefs: Restrict tracefs when the kernel is locked down")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Pull char/misc driver fixes from Greg KH:
 "Here are some small char/misc driver fixes for 5.4-rc3.

  Nothing huge here. Some binder driver fixes (although it is still
  being discussed if these all fix the reported issues or not, so more
  might be coming later), some mei device ids and fixes, and a google
  firmware driver bugfix that fixes a regression, as well as some other
  tiny fixes.

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

* tag 'char-misc-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  firmware: google: increment VPD key_len properly
  w1: ds250x: Fix build error without CRC16
  virt: vbox: fix memory leak in hgcm_call_preprocess_linaddr
  binder: Fix comment headers on binder_alloc_prepare_to_free()
  binder: prevent UAF read in print_binder_transaction_log_entry()
  misc: fastrpc: prevent memory leak in fastrpc_dma_buf_attach
  mei: avoid FW version request on Ibex Peak and earlier
  mei: me: add comet point (lake) LP device ids

Pull staging/IIO driver fixes from Greg KH:
 "Here are some staging and IIO driver fixes for 5.4-rc3.

  The "biggest" thing here is a removal of the fbtft device and flexfb
  code as they have been abandoned by their authors and are no longer
  needed for that hardware.

  Other than that, the usual amount of staging driver and iio driver
  fixes for reported issues, and some speakup sysfs file documentation,
  which has been long awaited for.

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

* tag 'staging-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (32 commits)
  iio: Fix an undefied reference error in noa1305_probe
  iio: light: opt3001: fix mutex unlock race
  iio: adc: ad799x: fix probe error handling
  iio: light: add missing vcnl4040 of_compatible
  iio: light: fix vcnl4000 devicetree hooks
  iio: imu: st_lsm6dsx: fix waitime for st_lsm6dsx i2c controller
  iio: adc: axp288: Override TS pin bias current for some models
  iio: imu: adis16400: fix memory leak
  iio: imu: adis16400: release allocated memory on failure
  iio: adc: stm32-adc: fix a race when using several adcs with dma and irq
  iio: adc: stm32-adc: move registers definitions
  iio: accel: adxl372: Perform a reset at start up
  iio: accel: adxl372: Fix push to buffers lost samples
  iio: accel: adxl372: Fix/remove limitation for FIFO samples
  iio: adc: hx711: fix bug in sampling of data
  staging: vt6655: Fix memory leak in vt6655_probe
  staging: exfat: Use kvzalloc() instead of kzalloc() for exfat_sb_info
  Staging: fbtft: fix memory leak in fbtft_framebuffer_alloc
  staging: speakup: document sysfs attributes
  staging: rtl8188eu: fix HighestRate check in odm_ARFBRefresh_8188E()
  ...

Pull tty/serial driver fixes from Greg KH:
 "Here are some small tty and serial driver fixes for 5.4-rc3 that
  resolve a number of reported issues and regressions.

  None of these are huge, full details are in the shortlog. There's also
  a MAINTAINERS update that I think you might have already taken in your
  tree already, but git should handle that merge easily.

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

* tag 'tty-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  MAINTAINERS: kgdb: Add myself as a reviewer for kgdb/kdb
  tty: serial: imx: Use platform_get_irq_optional() for optional IRQs
  serial: fix kernel-doc warning in comments
  serial: 8250_omap: Fix gpio check for auto RTS/CTS
  serial: mctrl_gpio: Check for NULL pointer
  tty: serial: fsl_lpuart: Fix lpuart_flush_buffer()
  tty: serial: Fix PORT_LINFLEXUART definition
  tty: n_hdlc: fix build on SPARC
  serial: uartps: Fix uartps_major handling
  serial: uartlite: fix exit path null pointer
  tty: serial: linflexuart: Fix magic SysRq handling
  serial: sh-sci: Use platform_get_irq_optional() for optional interrupts
  dt-bindings: serial: sh-sci: Document r8a774b1 bindings
  serial/sifive: select SERIAL_EARLYCON
  tty: serial: rda: Fix the link time qualifier of 'rda_uart_exit()'
  tty: serial: owl: Fix the link time qualifier of 'owl_uart_exit()'

Pull USB fixes from Greg KH:
 "Here are a lot of small USB driver fixes for 5.4-rc3.

  syzbot has stepped up its testing of the USB driver stack, now able to
  trigger fun race conditions between disconnect and probe functions.
  Because of that we have a lot of fixes in here from Johan and others
  fixing these reported issues that have been around since almost all
  time.

  We also are just deleting the rio500 driver, making all of the syzbot
  bugs found in it moot as it turns out no one has been using it for
  years as there is a userspace version that is being used instead.

  There are also a number of other small fixes in here, all resolving
  reported issues or regressions.

  All have been in linux-next without any reported issues"

* tag 'usb-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (65 commits)
  USB: yurex: fix NULL-derefs on disconnect
  USB: iowarrior: use pr_err()
  USB: iowarrior: drop redundant iowarrior mutex
  USB: iowarrior: drop redundant disconnect mutex
  USB: iowarrior: fix use-after-free after driver unbind
  USB: iowarrior: fix use-after-free on release
  USB: iowarrior: fix use-after-free on disconnect
  USB: chaoskey: fix use-after-free on release
  USB: adutux: fix use-after-free on release
  USB: ldusb: fix NULL-derefs on driver unbind
  USB: legousbtower: fix use-after-free on release
  usb: cdns3: Fix for incorrect DMA mask.
  usb: cdns3: fix cdns3_core_init_role()
  usb: cdns3: gadget: Fix full-speed mode
  USB: usb-skeleton: drop redundant in-urb check
  USB: usb-skeleton: fix use-after-free after driver unbind
  USB: usb-skeleton: fix NULL-deref on disconnect
  usb:cdns3: Fix for CV CH9 running with g_zero driver.
  usb: dwc3: Remove dev_err() on platform_get_irq() failure
  usb: dwc3: Switch to platform_get_irq_byname_optional()
  ...

Pull scheduler fixes from Ingo Molnar:
 "Two fixes: a guest-cputime accounting fix, and a cgroup bandwidth
  quota precision fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/vtime: Fix guest/system mis-accounting on task switch
  sched/fair: Scale bandwidth quota and period without losing quota/period ratio precision

Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, but also a couple of updates for new Intel
  models (which are technically hw-enablement, but to users it's a fix
  to perf behavior on those new CPUs - hope this is fine), an AUX
  inheritance fix, event time-sharing fix, and a fix for lost non-perf
  NMI events on AMD systems"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  perf/x86/cstate: Add Tiger Lake CPU support
  perf/x86/msr: Add Tiger Lake CPU support
  perf/x86/intel: Add Tiger Lake CPU support
  perf/x86/cstate: Update C-state counters for Ice Lake
  perf/x86/msr: Add new CPU model numbers for Ice Lake
  perf/x86/cstate: Add Comet Lake CPU support
  perf/x86/msr: Add Comet Lake CPU support
  perf/x86/intel: Add Comet Lake CPU support
  perf/x86/amd: Change/fix NMI latency mitigation to use a timestamp
  perf/core: Fix corner case in perf_rotate_context()
  perf/core: Rework memory accounting in perf_mmap()
  perf/core: Fix inheritance of aux_output groups
  perf annotate: Don't return -1 for error when doing BPF disassembly
  perf annotate: Return appropriate error code for allocation failures
  perf annotate: Fix arch specific ->init() failure errors
  perf annotate: Propagate the symbol__annotate() error return
  perf annotate: Fix the signedness of failure returns
  perf annotate: Propagate perf_env__arch() error
  perf evsel: Fall back to global 'perf_env' in perf_evsel__env()
  perf tools: Propagate get_cpuid() error
  ...

Pull EFI fixes from Ingo Molnar:
 "Misc EFI fixes all across the map: CPER error report fixes, fixes to
  TPM event log parsing, fix for a kexec hang, a Sparse fix and other
  fixes"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/tpm: Fix sanity check of unsigned tbl_size being less than zero
  efi/x86: Do not clean dummy variable in kexec path
  efi: Make unexported efi_rci2_sysfs_init() static
  efi/tpm: Only set 'efi_tpm_final_log_size' after successful event log parsing
  efi/tpm: Don't traverse an event log with no events
  efi/tpm: Don't access event->count when it isn't mapped
  efivar/ssdt: Don't iterate over EFI vars if no SSDT override was specified
  efi/cper: Fix endianness of PCIe class code

Pull x86 fixes from Ingo Molnar:
 "A handful of fixes: a kexec linking fix, an AMD MWAITX fix, a vmware
  guest support fix when built under Clang, and new CPU model number
  definitions"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Add Comet Lake to the Intel CPU models header
  lib/string: Make memzero_explicit() inline instead of external
  x86/cpu/vmware: Use the full form of INL in VMWARE_PORT
  x86/asm: Fix MWAITX C-state hint value

Pull x86 license tag fixlets from Ingo Molnar:
 "Fix a couple of SPDX tags in x86 headers to follow the canonical
  pattern"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Use the correct SPDX License Identifier in headers

Pull RISC-V fixes from Paul Walmsley:

 - Fix several bugs in the breakpoint trap handler

 - Drop an unnecessary loop around calls to preempt_schedule_irq()

* tag 'riscv/for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  RISC-V: entry: Remove unneeded need_resched() loop
  riscv: Correct the handling of unexpected ebreak in do_trap_break()
  riscv: avoid sending a SIGTRAP to a user thread trapped in WARN()
  riscv: avoid kernel hangs when trapped in BUG()

Pull MIPS fixes from Paul Burton:

 - Build fixes for CONFIG_OPTIMIZE_INLINING=y builds in which the
   compiler may choose not to inline __xchg() & __cmpxchg().

 - A build fix for Loongson configurations with GCC 9.x.

 - Expose some extra HWCAP bits to indicate support for various
   instruction set extensions to userland.

 - Fix bad stack access in firmware handling code for old SNI
   RM200/300/400 machines.

* tag 'mips_fixes_5.4_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: Disable Loongson MMI instructions for kernel build
  MIPS: elf_hwcap: Export userspace ASEs
  MIPS: fw: sni: Fix out of bounds init of o32 stack
  MIPS: include: Mark __xchg as __always_inline
  MIPS: include: Mark __cmpxchg as __always_inline

Pull powerpc fixes from Michael Ellerman:
 "Fix a kernel crash in spufs_create_root() on Cell machines, since the
  new mount API went in.

  Fix a regression in our KVM code caused by our recent PCR changes.

  Avoid a warning message about a failing hypervisor API on systems that
  don't have that API.

  A couple of minor build fixes.

  Thanks to: Alexey Kardashevskiy, Alistair Popple, Desnes A. Nunes do
  Rosario, Emmanuel Nicolet, Jordan Niethe, Laurent Dufour, Stephen
  Rothwell"

* tag 'powerpc-5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  spufs: fix a crash in spufs_create_root()
  powerpc/kvm: Fix kvmppc_vcore->in_guest value in kvmhv_switch_to_host
  selftests/powerpc: Fix compile error on tlbie_test due to newer gcc
  powerpc/pseries: Remove confusing warning message.
  powerpc/64s/radix: Fix build failure with RADIX_MMU=n

Pull xen fixes from Juergen Gross:

 - correct panic handling when running as a Xen guest

 - cleanup the Xen grant driver to remove printing a pointer being
   always NULL

 - remove a soon to be wrong call of of_dma_configure()

* tag 'for-linus-5.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Stop abusing DT of_dma_configure API
  xen/grant-table: remove unnecessary printing
  x86/xen: Return from panic notifier

Pull s390 fixes from Vasily Gorbik:

 - Fix virtio-ccw DMA regression

 - Fix compiler warnings in uaccess

* tag 's390-5.4-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/uaccess: avoid (false positive) compiler warnings
  s390/cio: fix virtio-ccw DMA without PV

Tiger Lake is the followon to Ice Lake. From the perspective of Intel
cstate residency counters, there is nothing changed compared with
Ice Lake.

Share icl_cstates with Ice Lake.
Update the comments for Tiger Lake.

The External Design Specification (EDS) is not published yet. It comes
from an authoritative internal source.

The patch has been tested on real hardware.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1570549810-25049-10-git-send-email-kan.liang@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Tiger Lake is the followon to Ice Lake. PPERF and SMI_COUNT MSRs are
also supported.

The External Design Specification (EDS) is not published yet. It comes
from an authoritative internal source.

The patch has been tested on real hardware.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1570549810-25049-9-git-send-email-kan.liang@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Tiger Lake is the followon to Ice Lake. From the perspective of Intel
core PMU, there is little changes compared with Ice Lake, e.g. small
changes in event list. But it doesn't impact on core PMU functionality.
Share the perf code with Ice Lake. The event list patch will be submitted
later separately.

The patch has been tested on real hardware.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1570549810-25049-8-git-send-email-kan.liang@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

There is no Core C3 C-State counter for Ice Lake.
Package C8/C9/C10 C-State counters are added for Ice Lake.

Introduce a new event list, icl_cstates, for Ice Lake.
Update the comments accordingly.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: f08c47d1 ("perf/x86/intel/cstate: Add Icelake support")
Link: https://lkml.kernel.org/r/1570549810-25049-7-git-send-email-kan.liang@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>