Jens Axboe a6da0024ff blktrace: fix unlocked registration of tracepoints ... 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>		2017-11-10 19:53:25 -07:00
..
blktrace.c	blktrace: fix unlocked registration of tracepoints	2017-11-10 19:53:25 -07:00
bpf_trace.c	bpf: fix bpf_trace_printk on 32 bit archs	2017-08-15 17:32:15 -07:00
ftrace.c	ftrace: Fix memleak when unregistering dynamic ops when tracing disabled	2017-09-01 13:55:49 -04:00
Kconfig
Makefile
power-traces.c
ring_buffer_benchmark.c	ring-buffer: Have ring_buffer_alloc_read_page() return error on offline CPU	2017-08-02 14:23:02 -04:00
ring_buffer.c	ring-buffer: Have ring_buffer_alloc_read_page() return error on offline CPU	2017-08-02 14:23:02 -04:00
rpm-traces.c
trace_benchmark.c
trace_benchmark.h
trace_branch.c
trace_clock.c
trace_entries.h
trace_event_perf.c	perf/ftrace: Fix double traces of perf on ftrace:function	2017-08-29 13:29:29 +02:00
trace_events_filter_test.h
trace_events_filter.c	mm: treewide: remove GFP_TEMPORARY allocation flag	2017-09-13 18:53:16 -07:00
trace_events_hist.c
trace_events_trigger.c
trace_events.c	tracing: Fix clear of RECORDED_TGID flag when disabling trace event	2017-09-05 12:00:09 -04:00
trace_export.c
trace_functions_graph.c	treewide: make "nr_cpu_ids" unsigned	2017-09-08 18:26:48 -07:00
trace_functions.c
trace_hwlat.c
trace_irqsoff.c
trace_kdb.c
trace_kprobe.c	perf/ftrace: Fix double traces of perf on ftrace:function	2017-08-29 13:29:29 +02:00
trace_mmiotrace.c	tracing: Ignore mmiotrace from kernel commandline	2017-09-19 12:36:01 -04:00
trace_nop.c
trace_output.c
trace_output.h
trace_printk.c
trace_probe.c
trace_probe.h
trace_sched_switch.c
trace_sched_wakeup.c
trace_selftest_dynamic.c
trace_selftest.c	ftrace: Fix selftest goto location on error	2017-09-01 12:04:09 -04:00
trace_seq.c
trace_stack.c	tracing: Remove RCU work arounds from stack tracer	2017-09-23 16:50:20 -04:00
trace_stat.c
trace_stat.h
trace_syscalls.c	perf/bpf: fix a clang compilation issue	2017-09-11 14:28:45 -07:00
trace_uprobe.c	perf/ftrace: Fix double traces of perf on ftrace:function	2017-08-29 13:29:29 +02:00
trace.c	tracing: Fix trace_pipe behavior for instance traces	2017-09-19 18:33:42 -04:00
trace.h	tracing: Ignore mmiotrace from kernel commandline	2017-09-19 12:36:01 -04:00
tracing_map.c	tracing: Fix kmemleak in tracing_map_array_free()	2017-08-24 10:05:51 -04:00
tracing_map.h