linux-uconsole/kernel/trace
Jens Axboe 28de93896a blktrace: fix unlocked registration of tracepoints
commit a6da0024ff upstream.

We need to ensure that tracepoints are registered and unregistered
with the users of them. The existing atomic count isn't enough for
that. Add a lock around the tracepoints, so we serialize access
to them.

This fixes cases where we have multiple users setting up and
tearing down tracepoints, like this:

CPU: 0 PID: 2995 Comm: syzkaller857118 Not tainted
4.14.0-rc5-next-20171018+ #36
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:16 [inline]
  dump_stack+0x194/0x257 lib/dump_stack.c:52
  panic+0x1e4/0x41c kernel/panic.c:183
  __warn+0x1c4/0x1e0 kernel/panic.c:546
  report_bug+0x211/0x2d0 lib/bug.c:183
  fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:177
  do_trap_no_signal arch/x86/kernel/traps.c:211 [inline]
  do_trap+0x260/0x390 arch/x86/kernel/traps.c:260
  do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:297
  do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:310
  invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905
RIP: 0010:tracepoint_add_func kernel/tracepoint.c:210 [inline]
RIP: 0010:tracepoint_probe_register_prio+0x397/0x9a0 kernel/tracepoint.c:283
RSP: 0018:ffff8801d1d1f6c0 EFLAGS: 00010293
RAX: ffff8801d22e8540 RBX: 00000000ffffffef RCX: ffffffff81710f07
RDX: 0000000000000000 RSI: ffffffff85b679c0 RDI: ffff8801d5f19818
RBP: ffff8801d1d1f7c8 R08: ffffffff81710c10 R09: 0000000000000004
R10: ffff8801d1d1f6b0 R11: 0000000000000003 R12: ffffffff817597f0
R13: 0000000000000000 R14: 00000000ffffffff R15: ffff8801d1d1f7a0
  tracepoint_probe_register+0x2a/0x40 kernel/tracepoint.c:304
  register_trace_block_rq_insert include/trace/events/block.h:191 [inline]
  blk_register_tracepoints+0x1e/0x2f0 kernel/trace/blktrace.c:1043
  do_blk_trace_setup+0xa10/0xcf0 kernel/trace/blktrace.c:542
  blk_trace_setup+0xbd/0x180 kernel/trace/blktrace.c:564
  sg_ioctl+0xc71/0x2d90 drivers/scsi/sg.c:1089
  vfs_ioctl fs/ioctl.c:45 [inline]
  do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685
  SYSC_ioctl fs/ioctl.c:700 [inline]
  SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691
  entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x444339
RSP: 002b:00007ffe05bb5b18 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000006d66c0 RCX: 0000000000444339
RDX: 000000002084cf90 RSI: 00000000c0481273 RDI: 0000000000000009
RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: ffffffffffffffff
R13: 00000000c0481273 R14: 0000000000000000 R15: 0000000000000000

since we can now run these in parallel. Ensure that the exported helpers
for doing this are grabbing the queue trace mutex.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:35 +01:00
..
blktrace.c blktrace: fix unlocked registration of tracepoints 2018-02-25 11:03:35 +01:00
bpf_trace.c bpf: make tracing helpers gpl only 2015-10-26 21:53:34 -07:00
ftrace.c ftrace: Remove incorrect setting of glob search field 2018-02-16 20:09:47 +01:00
Kconfig Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-11-10 18:11:41 -08:00
Makefile Makefile: Mute warning for __builtin_return_address(>0) for tracing only 2016-09-30 10:18:35 +02:00
power-traces.c PM / sleep: export suspend_resume trace event 2015-01-30 02:10:41 +01:00
ring_buffer.c ring-buffer: Mask out the info bits when returning buffer page length 2018-01-02 20:33:22 +01:00
ring_buffer_benchmark.c ring_buffer: Remove unneeded smp_wmb() before wakeup of reader benchmark 2015-11-03 16:19:02 -05:00
rpm-traces.c
trace.c tracing: Fix crash when it fails to alloc ring buffer 2018-01-02 20:33:22 +01:00
trace.h tracing: Remove unused ftrace_cpu_disabled per cpu variable 2015-11-07 13:25:14 -05:00
trace_benchmark.c tracing: Only benchmark the time tracepoints take if tracing is on 2015-11-02 13:34:58 -05:00
trace_benchmark.h tracing: Add tracepoint benchmark tracepoint 2014-05-29 22:49:54 -04:00
trace_branch.c tracing: Remove {start,stop}_branch_trace 2015-10-21 10:10:09 -04:00
trace_clock.c tracing: Export tracing clock functions 2015-05-12 15:56:57 -04:00
trace_entries.h tracing: %pF is only for function pointers 2015-03-25 08:57:22 -04:00
trace_event_perf.c treewide: Remove old email address 2015-11-23 09:44:58 +01:00
trace_events.c tracing: Fix converting enum's from the map in trace_event_eval_update() 2018-01-23 19:50:16 +01:00
trace_events_filter.c tracing: Fix freeing of filter in create_filter() when set_str is false 2017-08-30 10:19:24 +02:00
trace_events_filter_test.h
trace_events_trigger.c tracing: Rename ftrace_raw_##call event structures to trace_event_raw_##call 2015-05-13 21:48:40 -04:00
trace_export.c tracing: ftrace_event_is_function() can return boolean 2015-11-02 14:28:05 -05:00
trace_functions.c tracing/trivial: Fix typos and make an int into a bool 2014-11-20 10:05:36 -05:00
trace_functions_graph.c fgraph: Handle a case where a tracer ignores set_graph_notrace 2017-01-09 08:07:50 +01:00
trace_irqsoff.c tracing: Have preempt(irqs)off trace preempt disabled functions 2016-04-12 09:08:59 -07:00
trace_kdb.c tracing: Move trace_flags from global to a trace_array field 2015-09-30 15:22:55 -04:00
trace_kprobe.c tracing/kprobes: Allow to create probe with a module name starting with a digit 2017-07-15 11:57:45 +02:00
trace_mmiotrace.c tracing: Pass trace_array into trace_buffer_unlock_commit() 2015-09-25 17:38:44 -04:00
trace_nop.c tracing: Remove unneeded includes of debugfs.h and fs.h 2015-01-22 11:19:48 -05:00
trace_output.c tracing: Move trace_flags from global to a trace_array field 2015-09-30 15:22:55 -04:00
trace_output.h tracing: Turn seq_print_user_ip() into a static function 2015-09-28 10:16:12 -04:00
trace_printk.c tracing: Handle NULL formats in hold_module_trace_bprintk_format() 2016-07-27 09:47:32 -07:00
trace_probe.c trace: Don't use __weak in header files 2015-03-25 08:57:23 -04:00
trace_probe.h kernel/trace_probe: is_good_name can be boolean 2015-09-22 13:11:30 -04:00
trace_sched_switch.c sched/core: Fix trace_sched_switch() 2015-10-06 17:08:15 +02:00
trace_sched_wakeup.c Most of the changes are clean ups and small fixes. Some of them have 2015-11-06 13:30:20 -08:00
trace_selftest.c ftrace: Fix selftest goto location on error 2017-09-27 11:00:16 +02:00
trace_selftest_dynamic.c
trace_seq.c tracing: use %*pb[l] to print bitmaps including cpumasks and nodemasks 2015-02-13 21:21:37 -08:00
trace_stack.c tracing/stacktrace: Show entire trace if passed in function not found 2016-02-17 12:30:57 -08:00
trace_stat.c tracing: Convert the tracing facility over to use tracefs 2015-02-03 12:48:41 -05:00
trace_stat.h
trace_syscalls.c tracing: Move trace_flags from global to a trace_array field 2015-09-30 15:22:55 -04:00
trace_uprobe.c tracing/uprobes: Do not print '0x (null)' when offset is 0 2015-08-26 10:43:01 -03:00