* Re: possible deadlock in perf_event_ctx_lock_nested [not found] <001a11448f6c0346ec055c831a71@google.com> @ 2017-10-27 8:31 ` Dmitry Vyukov 2017-10-27 15:11 ` Peter Zijlstra 1 sibling, 0 replies; 5+ messages in thread From: Dmitry Vyukov @ 2017-10-27 8:31 UTC (permalink / raw) To: syzbot Cc: Arnaldo Carvalho de Melo, Alexander Shishkin, LKML, Ingo Molnar, Peter Zijlstra, syzkaller-bugs On Fri, Oct 27, 2017 at 10:30 AM, syzbot <bot+f67ad450a4bd1e42a7bd09f592904b15be39db7a@syzkaller.appspotmail.com> wrote: > Hello, > > syzkaller hit the following crash on > a31cc455c512f3f1dd5f79cac8e29a7c8a617af8 > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached > Raw console output is attached. Last happened on upstream 68ebe3cbe786a954481d6ded0dc83f7d551640bf (Oct 9). > ====================================================== > WARNING: possible circular locking dependency detected > 4.13.0-next-20170911+ #19 Not tainted > ------------------------------------------------------ > syz-executor2/12380 is trying to acquire lock: > (&ctx->mutex){+.+.}, at: [<ffffffff8180923c>] > perf_event_ctx_lock_nested+0x1dc/0x3c0 kernel/events/core.c:1210 > > but task is already holding lock: > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock_nested > fs/pipe.c:66 [inline] > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock+0x56/0x70 > fs/pipe.c:74 > > which lock already depends on the new lock. > > > the existing dependency chain (in reverse order) is: > > -> #8 (&pipe->mutex/1){+.+.}: > check_prevs_add kernel/locking/lockdep.c:2020 [inline] > validate_chain kernel/locking/lockdep.c:2469 [inline] > __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 > lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 > __mutex_lock_common kernel/locking/mutex.c:756 [inline] > __mutex_lock+0x16f/0x1870 kernel/locking/mutex.c:893 > mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 > pipe_lock_nested fs/pipe.c:66 [inline] > pipe_lock+0x56/0x70 fs/pipe.c:74 > iter_file_splice_write+0x264/0xf50 fs/splice.c:699 > do_splice_from fs/splice.c:851 [inline] > do_splice fs/splice.c:1147 [inline] > SYSC_splice fs/splice.c:1402 [inline] > SyS_splice+0x7d5/0x1630 fs/splice.c:1382 > entry_SYSCALL_64_fastpath+0x1f/0xbe > > -> #7 (sb_writers){.+.+}: > percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:35 > [inline] > percpu_down_read include/linux/percpu-rwsem.h:58 [inline] > __sb_start_write+0x18f/0x290 fs/super.c:1341 > sb_start_write include/linux/fs.h:1541 [inline] > mnt_want_write+0x3f/0xb0 fs/namespace.c:387 > filename_create+0x12b/0x520 fs/namei.c:3628 > kern_path_create+0x33/0x40 fs/namei.c:3674 > handle_create+0xc0/0x760 drivers/base/devtmpfs.c:203 > > -> #6 ((complete)&req.done){+.+.}: > check_prevs_add kernel/locking/lockdep.c:2020 [inline] > validate_chain kernel/locking/lockdep.c:2469 [inline] > __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 > lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 > complete_acquire include/linux/completion.h:39 [inline] > __wait_for_common kernel/sched/completion.c:108 [inline] > wait_for_common kernel/sched/completion.c:122 [inline] > wait_for_completion+0xc8/0x770 kernel/sched/completion.c:143 > devtmpfs_create_node+0x32b/0x4a0 drivers/base/devtmpfs.c:115 > device_add+0x120f/0x1640 drivers/base/core.c:1824 > device_create_groups_vargs+0x1f3/0x250 drivers/base/core.c:2430 > device_create_vargs drivers/base/core.c:2470 [inline] > device_create+0xda/0x110 drivers/base/core.c:2506 > msr_device_create+0x26/0x40 arch/x86/kernel/msr.c:188 > cpuhp_invoke_callback+0x256/0x14d0 kernel/cpu.c:145 > cpuhp_thread_fun+0x265/0x520 kernel/cpu.c:434 > smpboot_thread_fn+0x489/0x850 kernel/smpboot.c:164 > kthread+0x39c/0x470 kernel/kthread.c:231 > ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 > > -> #5 (cpuhp_state){+.+.}: > check_prevs_add kernel/locking/lockdep.c:2020 [inline] > validate_chain kernel/locking/lockdep.c:2469 [inline] > __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 > lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 > cpuhp_invoke_ap_callback kernel/cpu.c:467 [inline] > cpuhp_issue_call+0x1a2/0x3e0 kernel/cpu.c:1308 > __cpuhp_setup_state_cpuslocked+0x2d6/0x5f0 kernel/cpu.c:1455 > __cpuhp_setup_state+0xb0/0x140 kernel/cpu.c:1484 > cpuhp_setup_state include/linux/cpuhotplug.h:177 [inline] > page_writeback_init+0x4d/0x71 mm/page-writeback.c:2082 > pagecache_init+0x48/0x4f mm/filemap.c:871 > start_kernel+0x6c1/0x754 init/main.c:690 > x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:377 > x86_64_start_kernel+0x87/0x8a arch/x86/kernel/head64.c:358 > verify_cpu+0x0/0xfb > > -> #4 (cpuhp_state_mutex){+.+.}: > check_prevs_add kernel/locking/lockdep.c:2020 [inline] > validate_chain kernel/locking/lockdep.c:2469 [inline] > __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 > lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 > __mutex_lock_common kernel/locking/mutex.c:756 [inline] > __mutex_lock+0x16f/0x1870 kernel/locking/mutex.c:893 > mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 > __cpuhp_setup_state_cpuslocked+0x5b/0x5f0 kernel/cpu.c:1430 > __cpuhp_setup_state+0xb0/0x140 kernel/cpu.c:1484 > cpuhp_setup_state_nocalls include/linux/cpuhotplug.h:205 [inline] > kvm_guest_init+0x1f3/0x20f arch/x86/kernel/kvm.c:488 > setup_arch+0x1899/0x1ab3 arch/x86/kernel/setup.c:1295 > start_kernel+0xa5/0x754 init/main.c:530 > x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:377 > x86_64_start_kernel+0x87/0x8a arch/x86/kernel/head64.c:358 > verify_cpu+0x0/0xfb > > -> #3 (cpu_hotplug_lock.rw_sem){++++}: > check_prevs_add kernel/locking/lockdep.c:2020 [inline] > validate_chain kernel/locking/lockdep.c:2469 [inline] > __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 > lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 > percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:35 > [inline] > percpu_down_read include/linux/percpu-rwsem.h:58 [inline] > cpus_read_lock+0x42/0x90 kernel/cpu.c:218 > static_key_slow_inc+0x9d/0x3c0 kernel/jump_label.c:123 > tracepoint_add_func kernel/tracepoint.c:223 [inline] > tracepoint_probe_register_prio+0x80d/0x9a0 kernel/tracepoint.c:283 > tracepoint_probe_register+0x2a/0x40 kernel/tracepoint.c:304 > trace_event_reg+0x167/0x320 kernel/trace/trace_events.c:305 > perf_trace_event_reg kernel/trace/trace_event_perf.c:122 [inline] > perf_trace_event_init kernel/trace/trace_event_perf.c:197 [inline] > perf_trace_init+0x4f9/0xab0 kernel/trace/trace_event_perf.c:221 > perf_tp_event_init+0x7d/0xf0 kernel/events/core.c:8037 > perf_try_init_event+0xc9/0x1f0 kernel/events/core.c:9261 > perf_init_event kernel/events/core.c:9299 [inline] > perf_event_alloc+0x1c5b/0x2a00 kernel/events/core.c:9558 > SYSC_perf_event_open+0x84e/0x2e00 kernel/events/core.c:10013 > SyS_perf_event_open+0x39/0x50 kernel/events/core.c:9899 > entry_SYSCALL_64_fastpath+0x1f/0xbe > > -> #2 (tracepoints_mutex){+.+.}: > check_prevs_add kernel/locking/lockdep.c:2020 [inline] > validate_chain kernel/locking/lockdep.c:2469 [inline] > __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 > lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 > __mutex_lock_common kernel/locking/mutex.c:756 [inline] > __mutex_lock+0x16f/0x1870 kernel/locking/mutex.c:893 > mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 > tracepoint_probe_register_prio+0xa0/0x9a0 kernel/tracepoint.c:279 > tracepoint_probe_register+0x2a/0x40 kernel/tracepoint.c:304 > trace_event_reg+0x167/0x320 kernel/trace/trace_events.c:305 > perf_trace_event_reg kernel/trace/trace_event_perf.c:122 [inline] > perf_trace_event_init kernel/trace/trace_event_perf.c:197 [inline] > perf_trace_init+0x4f9/0xab0 kernel/trace/trace_event_perf.c:221 > perf_tp_event_init+0x7d/0xf0 kernel/events/core.c:8037 > perf_try_init_event+0xc9/0x1f0 kernel/events/core.c:9261 > perf_init_event kernel/events/core.c:9299 [inline] > perf_event_alloc+0x1c5b/0x2a00 kernel/events/core.c:9558 > SYSC_perf_event_open+0x84e/0x2e00 kernel/events/core.c:10013 > SyS_perf_event_open+0x39/0x50 kernel/events/core.c:9899 > entry_SYSCALL_64_fastpath+0x1f/0xbe > > -> #1 (event_mutex){+.+.}: > check_prevs_add kernel/locking/lockdep.c:2020 [inline] > validate_chain kernel/locking/lockdep.c:2469 [inline] > __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 > lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 > __mutex_lock_common kernel/locking/mutex.c:756 [inline] > __mutex_lock+0x16f/0x1870 kernel/locking/mutex.c:893 > mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 > ftrace_profile_set_filter+0x7a/0x270 > kernel/trace/trace_events_filter.c:2266 > perf_event_set_filter kernel/events/core.c:8622 [inline] > _perf_ioctl kernel/events/core.c:4785 [inline] > perf_ioctl+0x1026/0x1360 kernel/events/core.c:4822 > vfs_ioctl fs/ioctl.c:45 [inline] > do_vfs_ioctl+0x1b1/0x1530 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 > > -> #0 (&ctx->mutex){+.+.}: > check_prev_add+0x865/0x1520 kernel/locking/lockdep.c:1894 > check_prevs_add kernel/locking/lockdep.c:2020 [inline] > validate_chain kernel/locking/lockdep.c:2469 [inline] > __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 > lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 > __mutex_lock_common kernel/locking/mutex.c:756 [inline] > __mutex_lock+0x16f/0x1870 kernel/locking/mutex.c:893 > mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 > perf_event_ctx_lock_nested+0x1dc/0x3c0 kernel/events/core.c:1210 > perf_event_ctx_lock kernel/events/core.c:1223 [inline] > perf_read+0xb9/0x970 kernel/events/core.c:4584 > do_loop_readv_writev fs/read_write.c:693 [inline] > do_iter_read+0x3db/0x5b0 fs/read_write.c:917 > vfs_readv+0x121/0x1c0 fs/read_write.c:979 > kernel_readv fs/splice.c:361 [inline] > default_file_splice_read+0x508/0xae0 fs/splice.c:416 > do_splice_to+0x110/0x170 fs/splice.c:880 > do_splice fs/splice.c:1173 [inline] > SYSC_splice fs/splice.c:1402 [inline] > SyS_splice+0x11a8/0x1630 fs/splice.c:1382 > entry_SYSCALL_64_fastpath+0x1f/0xbe > > other info that might help us debug this: > > Chain exists of: > &ctx->mutex --> sb_writers --> &pipe->mutex/1 > > Possible unsafe locking scenario: > > CPU0 CPU1 > ---- ---- > lock(&pipe->mutex/1); > lock(sb_writers); > lock(&pipe->mutex/1); > lock(&ctx->mutex); > > *** DEADLOCK *** > > 1 lock held by syz-executor2/12380: > #0: (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock_nested > fs/pipe.c:66 [inline] > #0: (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock+0x56/0x70 > fs/pipe.c:74 > > stack backtrace: > CPU: 1 PID: 12380 Comm: syz-executor2 Not tainted 4.13.0-next-20170911+ #19 > 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 > print_circular_bug+0x503/0x710 kernel/locking/lockdep.c:1259 > check_prev_add+0x865/0x1520 kernel/locking/lockdep.c:1894 > check_prevs_add kernel/locking/lockdep.c:2020 [inline] > validate_chain kernel/locking/lockdep.c:2469 [inline] > __lock_acquire+0x328f/0x4620 kernel/locking/lockdep.c:3498 > lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4002 > __mutex_lock_common kernel/locking/mutex.c:756 [inline] > __mutex_lock+0x16f/0x1870 kernel/locking/mutex.c:893 > mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 > perf_event_ctx_lock_nested+0x1dc/0x3c0 kernel/events/core.c:1210 > perf_event_ctx_lock kernel/events/core.c:1223 [inline] > perf_read+0xb9/0x970 kernel/events/core.c:4584 > do_loop_readv_writev fs/read_write.c:693 [inline] > do_iter_read+0x3db/0x5b0 fs/read_write.c:917 > vfs_readv+0x121/0x1c0 fs/read_write.c:979 > kernel_readv fs/splice.c:361 [inline] > default_file_splice_read+0x508/0xae0 fs/splice.c:416 > do_splice_to+0x110/0x170 fs/splice.c:880 > do_splice fs/splice.c:1173 [inline] > SYSC_splice fs/splice.c:1402 [inline] > SyS_splice+0x11a8/0x1630 fs/splice.c:1382 > entry_SYSCALL_64_fastpath+0x1f/0xbe > RIP: 0033:0x451e59 > RSP: 002b:00007ff32dce9c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000113 > RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 0000000000451e59 > RDX: 000000000000001b RSI: 0000000000000000 RDI: 000000000000001c > RBP: 0000000000000082 R08: 0000000200000005 R09: 0000000000000009 > R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000000000 > R13: 0000000000a6f7ef R14: 00007ff32dcea9c0 R15: 0000000000000000 > sctp: [Deprecated]: syz-executor1 (pid 12436) Use of struct sctp_assoc_value > in delayed_ack socket option. > Use struct sctp_sack_info instead > sctp: [Deprecated]: syz-executor1 (pid 12439) Use of struct sctp_assoc_value > in delayed_ack socket option. > Use struct sctp_sack_info instead > loop_reread_partitions: partition scan of loop0 (- \� t�@�� r�9h �x > G�Q:[��i�l � > �L�*� �@� ���R�-�T�r-�x�� ) failed (rc=-13) > QAT: Invalid ioctl > QAT: Invalid ioctl > QAT: Invalid ioctl > QAT: Invalid ioctl > sctp: [Deprecated]: syz-executor0 (pid 12525) Use of struct sctp_assoc_value > in delayed_ack socket option. > Use struct sctp_sack_info instead > sctp: [Deprecated]: syz-executor0 (pid 12525) Use of struct sctp_assoc_value > in delayed_ack socket option. > Use struct sctp_sack_info instead > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > xs_tcp_setup_socket: connect returned unhandled error -113 > IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready > kvm: pic: non byte write > kvm: pic: single mode not supported > QAT: Invalid ioctl > QAT: Invalid ioctl > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > sctp: [Deprecated]: syz-executor2 (pid 12946) Use of int in maxseg socket > option. > Use struct sctp_assoc_value instead > sctp: [Deprecated]: syz-executor2 (pid 12946) Use of int in maxseg socket > option. > Use struct sctp_assoc_value instead > nla_parse: 6 callbacks suppressed > netlink: 5 bytes leftover after parsing attributes in process > `syz-executor5'. > netlink: 5 bytes leftover after parsing attributes in process > `syz-executor5'. > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > kauditd_printk_skb: 65 callbacks suppressed > audit: type=1326 audit(1505176342.033:940): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=202 compat=0 ip=0x451e59 code=0x50000 > audit: type=1326 audit(1505176342.059:941): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=2 compat=0 ip=0x40c3e1 code=0x50000 > audit: type=1326 audit(1505176342.059:942): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=202 compat=0 ip=0x451e59 code=0x50000 > audit: type=1326 audit(1505176342.059:943): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=202 compat=0 ip=0x451e59 code=0x50000 > audit: type=1326 audit(1505176342.060:944): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=202 compat=0 ip=0x451e59 code=0x50000 > audit: type=1326 audit(1505176342.060:945): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=202 compat=0 ip=0x451e59 code=0x50000 > audit: type=1326 audit(1505176342.060:946): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=202 compat=0 ip=0x451e59 code=0x50000 > audit: type=1326 audit(1505176342.060:947): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=202 compat=0 ip=0x451e59 code=0x50000 > audit: type=1326 audit(1505176342.060:948): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=202 compat=0 ip=0x451e59 code=0x50000 > audit: type=1326 audit(1505176342.061:949): auid=4294967295 uid=0 gid=0 > ses=4294967295 subj=kernel pid=13113 comm="" exe="/root/syz-executor1" sig=0 > arch=c000003e syscall=202 compat=0 ip=0x451e59 code=0x50000 > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > QAT: Invalid ioctl > device syz5 entered promiscuous mode > QAT: Invalid ioctl > device syz5 left promiscuous mode > device syz5 entered promiscuous mode > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > do_dccp_getsockopt: sockopt(PACKET_SIZE) is deprecated: fix your app > do_dccp_getsockopt: sockopt(PACKET_SIZE) is deprecated: fix your app > device syz2 entered promiscuous mode > device syz2 left promiscuous mode > device syz2 entered promiscuous mode > netlink: 5 bytes leftover after parsing attributes in process > `syz-executor2'. > SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 > sclass=netlink_route_socket pig=13714 comm=syz-executor2 > FAULT_INJECTION: forcing a failure. > name failslab, interval 1, probability 0, space 0, times 1 > sctp: [Deprecated]: syz-executor1 (pid 13806) Use of int in max_burst socket > option. > Use struct sctp_assoc_value instead > CPU: 0 PID: 13805 Comm: syz-executor6 Not tainted 4.13.0-next-20170911+ #19 > 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 > fail_dump lib/fault-inject.c:51 [inline] > should_fail+0x8c0/0xa40 lib/fault-inject.c:149 > should_failslab+0xec/0x120 mm/failslab.c:31 > slab_pre_alloc_hook mm/slab.h:422 [inline] > slab_alloc mm/slab.c:3383 [inline] > __do_kmalloc mm/slab.c:3723 [inline] > __kmalloc_track_caller+0x5f/0x760 mm/slab.c:3740 > memdup_user+0x2c/0x90 mm/util.c:164 > map_lookup_elem+0x21c/0xb30 kernel/bpf/syscall.c:461 > SYSC_bpf kernel/bpf/syscall.c:1473 [inline] > SyS_bpf+0x1070/0x46a0 kernel/bpf/syscall.c:1451 > entry_SYSCALL_64_fastpath+0x1f/0xbe > RIP: 0033:0x451e59 > RSP: 002b:00007f75f19e1c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000141 > RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 0000000000451e59 > RDX: 0000000000000018 RSI: 00000000204a2fe8 RDI: 0000000000000001 > RBP: 00007f75f19e1a10 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004b69f7 > R13: 00007f75f19e1b48 R14: 00000000004b6a07 R15: 0000000000000000 > sctp: [Deprecated]: syz-executor1 (pid 13814) Use of int in max_burst socket > option. > Use struct sctp_assoc_value instead > sctp: [Deprecated]: syz-executor1 (pid 13873) Use of int in max_burst socket > option. > Use struct sctp_assoc_value instead > sctp: [Deprecated]: syz-executor1 (pid 13895) Use of int in max_burst socket > option. > Use struct sctp_assoc_value instead > FAULT_INJECTION: forcing a failure. > name failslab, interval 1, probability 0, space 0, times 0 > CPU: 1 PID: 14039 Comm: syz-executor3 Not tainted 4.13.0-next-20170911+ #19 > 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 > fail_dump lib/fault-inject.c:51 [inline] > should_fail+0x8c0/0xa40 lib/fault-inject.c:149 > should_failslab+0xec/0x120 mm/failslab.c:31 > slab_pre_alloc_hook mm/slab.h:422 [inline] > slab_alloc_node mm/slab.c:3304 [inline] > kmem_cache_alloc_node+0x56/0x760 mm/slab.c:3649 > __alloc_skb+0xf1/0x740 net/core/skbuff.c:194 > alloc_skb include/linux/skbuff.h:976 [inline] > tcp_xmit_probe_skb+0x67/0x360 net/ipv4/tcp_output.c:3599 > tcp_send_window_probe+0x11d/0x150 net/ipv4/tcp_output.c:3621 > do_tcp_setsockopt.isra.35+0xca7/0x1fd0 net/ipv4/tcp.c:2586 > tcp_setsockopt+0xb0/0xd0 net/ipv4/tcp.c:2801 > sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2960 > SYSC_setsockopt net/socket.c:1852 [inline] > SyS_setsockopt+0x189/0x360 net/socket.c:1831 > entry_SYSCALL_64_fastpath+0x1f/0xbe > RIP: 0033:0x451e59 > RSP: 002b:00007f1f8ae1bc08 EFLAGS: 00000216 ORIG_RAX: 0000000000000036 > RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 0000000000451e59 > RDX: 0000000000000013 RSI: 0000000000000006 RDI: 0000000000000005 > RBP: 00007f1f8ae1ba10 R08: 0000000000000004 R09: 0000000000000000 > R10: 0000000020d15000 R11: 0000000000000216 R12: 00000000004b69f7 > R13: 00007f1f8ae1bb48 R14: 00000000004b6a07 R15: 0000000000000000 > sg_write: data in/out 3171656/194 bytes for SCSI command 0x2a-- guessing > data in; > program syz-executor2 not setting count and/or reply_len properly > sg_write: data in/out 3171656/194 bytes for SCSI command 0x2a-- guessing > data in; > program syz-executor2 not setting count and/or reply_len properly > create_pit_timer: 19 callbacks suppressed > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > pit: kvm: requested 2514 ns i8254 timer period limited to 500000 ns > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkaller@googlegroups.com. > > syzbot will keep track of this bug report. > Once a fix for this bug is committed, please reply to this email with: > #syz fix: exact-commit-title > To mark this as a duplicate of another syzbot report, please reply with: > #syz dup: exact-subject-of-another-report > If it's a one-off invalid bug report, please reply with: > #syz invalid > Note: if the crash happens again, it will cause creation of a new bug > report. > > -- > You received this message because you are subscribed to the Google Groups > "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to syzkaller-bugs+unsubscribe@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/001a11448f6c0346ec055c831a71%40google.com. > For more options, visit https://groups.google.com/d/optout. ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: possible deadlock in perf_event_ctx_lock_nested [not found] <001a11448f6c0346ec055c831a71@google.com> 2017-10-27 8:31 ` possible deadlock in perf_event_ctx_lock_nested Dmitry Vyukov @ 2017-10-27 15:11 ` Peter Zijlstra 2017-10-27 15:33 ` Peter Zijlstra 1 sibling, 1 reply; 5+ messages in thread From: Peter Zijlstra @ 2017-10-27 15:11 UTC (permalink / raw) To: syzbot Cc: acme, alexander.shishkin, linux-kernel, mingo, syzkaller-bugs, Thomas Gleixner On Fri, Oct 27, 2017 at 01:30:30AM -0700, syzbot wrote: > ====================================================== > WARNING: possible circular locking dependency detected > 4.13.0-next-20170911+ #19 Not tainted > ------------------------------------------------------ > syz-executor2/12380 is trying to acquire lock: > (&ctx->mutex){+.+.}, at: [<ffffffff8180923c>] > perf_event_ctx_lock_nested+0x1dc/0x3c0 kernel/events/core.c:1210 > > but task is already holding lock: > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock_nested > fs/pipe.c:66 [inline] > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock+0x56/0x70 > fs/pipe.c:74 > > which lock already depends on the new lock. ARRGH!! that translates like the below, which is an absolute maze and requires at least 5 concurrent callstacks, possibly more. We already had a lot of fun with hotplug-perf-ftrace, but the below contains more. Let me try and page that previous crap back. perf_ioctl() #0 perf_event_ctx_lock() [ctx->mutex] perf_event_set_filter #1 ftrace_profile_set_filter [event_mutex] sys_perf_event_open ... perf_trace_init #1 mutex_lock [event_mutex] trace_event_reg tracepoint_probe_register #2 mutex_lock() [tracepoints_mutex] tracepoint_add_func() #3 static_key_slow_inc() [cpuhotplug_lock] cpuhp_setup_state_nocalls #3 cpus_read_lock [cpuhotplug_lock] __cpuhp_setup_state_cpuslocked #4 mutex_lock [cpuhp_state_mutex] cpuhp_issue_call #5 cpuhp_invoke_ap_callback() [cpuhp_state] #5 cpuhp_invoke_callback [cpuhp_state] ... devtmpfs_create_node #6 wait_for_completion() [&req.done] devtmpfsd handle_create #7 filename_create [sb_writers] #6 complete [&req.done] do_splice #7 file_start_write() [sb_writers] do_splice_from iter_file_splice_write #8 pipe_lock [pipe->mutex] do_splice #8 pipe_lock [pipe->mutex] do_splice_to ... #0 perf_read() [ctx->mutex] ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: possible deadlock in perf_event_ctx_lock_nested 2017-10-27 15:11 ` Peter Zijlstra @ 2017-10-27 15:33 ` Peter Zijlstra 2018-02-12 15:04 ` Dmitry Vyukov 0 siblings, 1 reply; 5+ messages in thread From: Peter Zijlstra @ 2017-10-27 15:33 UTC (permalink / raw) To: syzbot Cc: acme, alexander.shishkin, linux-kernel, mingo, syzkaller-bugs, Thomas Gleixner, Steven Rostedt, viro On Fri, Oct 27, 2017 at 05:11:37PM +0200, Peter Zijlstra wrote: > On Fri, Oct 27, 2017 at 01:30:30AM -0700, syzbot wrote: > > > ====================================================== > > WARNING: possible circular locking dependency detected > > 4.13.0-next-20170911+ #19 Not tainted > > ------------------------------------------------------ > > syz-executor2/12380 is trying to acquire lock: > > (&ctx->mutex){+.+.}, at: [<ffffffff8180923c>] > > perf_event_ctx_lock_nested+0x1dc/0x3c0 kernel/events/core.c:1210 > > > > but task is already holding lock: > > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock_nested > > fs/pipe.c:66 [inline] > > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock+0x56/0x70 > > fs/pipe.c:74 > > > > which lock already depends on the new lock. > > > ARRGH!! > > that translates like the below, which is an absolute maze and requires > at least 5 concurrent callstacks, possibly more. > > We already had a lot of fun with hotplug-perf-ftrace, but the below > contains more. Let me try and page that previous crap back. > > > > perf_ioctl() > #0 perf_event_ctx_lock() [ctx->mutex] > perf_event_set_filter > #1 ftrace_profile_set_filter [event_mutex] > > > > > sys_perf_event_open > ... > perf_trace_init > #1 mutex_lock [event_mutex] > trace_event_reg > tracepoint_probe_register > #2 mutex_lock() [tracepoints_mutex] > tracepoint_add_func() > #3 static_key_slow_inc() [cpuhotplug_lock] > > > > > > cpuhp_setup_state_nocalls > #3 cpus_read_lock [cpuhotplug_lock] > __cpuhp_setup_state_cpuslocked > #4 mutex_lock [cpuhp_state_mutex] > cpuhp_issue_call > #5 cpuhp_invoke_ap_callback() [cpuhp_state] > > > #5 cpuhp_invoke_callback [cpuhp_state] > ... > devtmpfs_create_node > #6 wait_for_completion() [&req.done] > > devtmpfsd > handle_create > #7 filename_create [sb_writers] > #6 complete [&req.done] > > > > > > > do_splice > #7 file_start_write() [sb_writers] > do_splice_from > iter_file_splice_write > #8 pipe_lock [pipe->mutex] > > > > > > do_splice > #8 pipe_lock [pipe->mutex] > do_splice_to > ... > #0 perf_read() [ctx->mutex] > So arguably that last op, splice_read from a perf fd is fairly pointless and we could dis-allow that. How about something like the below? --- kernel/events/core.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index 04989fb769f0..fd03f3082ee3 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -5468,6 +5468,13 @@ static int perf_fasync(int fd, struct file *filp, int on) return 0; } +static ssize_t perf_splice_read(struct file *file, loff_t *ppos, + struct pipe_inode_info *pope, size_t len, + unsigned int flags) +{ + return -EOPNOTSUPP; +} + static const struct file_operations perf_fops = { .llseek = no_llseek, .release = perf_release, @@ -5477,6 +5484,7 @@ static int perf_fasync(int fd, struct file *filp, int on) .compat_ioctl = perf_compat_ioctl, .mmap = perf_mmap, .fasync = perf_fasync, + .splice_read = perf_splice_read, }; /* ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: possible deadlock in perf_event_ctx_lock_nested 2017-10-27 15:33 ` Peter Zijlstra @ 2018-02-12 15:04 ` Dmitry Vyukov 2018-02-14 14:00 ` Dmitry Vyukov 0 siblings, 1 reply; 5+ messages in thread From: Dmitry Vyukov @ 2018-02-12 15:04 UTC (permalink / raw) To: Peter Zijlstra Cc: syzbot, Arnaldo Carvalho de Melo, Alexander Shishkin, LKML, Ingo Molnar, syzkaller-bugs, Thomas Gleixner, Steven Rostedt, Al Viro On Fri, Oct 27, 2017 at 5:33 PM, Peter Zijlstra <peterz@infradead.org> wrote: > On Fri, Oct 27, 2017 at 05:11:37PM +0200, Peter Zijlstra wrote: >> On Fri, Oct 27, 2017 at 01:30:30AM -0700, syzbot wrote: >> >> > ====================================================== >> > WARNING: possible circular locking dependency detected >> > 4.13.0-next-20170911+ #19 Not tainted >> > ------------------------------------------------------ >> > syz-executor2/12380 is trying to acquire lock: >> > (&ctx->mutex){+.+.}, at: [<ffffffff8180923c>] >> > perf_event_ctx_lock_nested+0x1dc/0x3c0 kernel/events/core.c:1210 >> > >> > but task is already holding lock: >> > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock_nested >> > fs/pipe.c:66 [inline] >> > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock+0x56/0x70 >> > fs/pipe.c:74 >> > >> > which lock already depends on the new lock. >> >> >> ARRGH!! >> >> that translates like the below, which is an absolute maze and requires >> at least 5 concurrent callstacks, possibly more. >> >> We already had a lot of fun with hotplug-perf-ftrace, but the below >> contains more. Let me try and page that previous crap back. >> >> >> >> perf_ioctl() >> #0 perf_event_ctx_lock() [ctx->mutex] >> perf_event_set_filter >> #1 ftrace_profile_set_filter [event_mutex] >> >> >> >> >> sys_perf_event_open >> ... >> perf_trace_init >> #1 mutex_lock [event_mutex] >> trace_event_reg >> tracepoint_probe_register >> #2 mutex_lock() [tracepoints_mutex] >> tracepoint_add_func() >> #3 static_key_slow_inc() [cpuhotplug_lock] >> >> >> >> >> >> cpuhp_setup_state_nocalls >> #3 cpus_read_lock [cpuhotplug_lock] >> __cpuhp_setup_state_cpuslocked >> #4 mutex_lock [cpuhp_state_mutex] >> cpuhp_issue_call >> #5 cpuhp_invoke_ap_callback() [cpuhp_state] >> >> >> #5 cpuhp_invoke_callback [cpuhp_state] >> ... >> devtmpfs_create_node >> #6 wait_for_completion() [&req.done] >> >> devtmpfsd >> handle_create >> #7 filename_create [sb_writers] >> #6 complete [&req.done] >> >> >> >> >> >> >> do_splice >> #7 file_start_write() [sb_writers] >> do_splice_from >> iter_file_splice_write >> #8 pipe_lock [pipe->mutex] >> >> >> >> >> >> do_splice >> #8 pipe_lock [pipe->mutex] >> do_splice_to >> ... >> #0 perf_read() [ctx->mutex] >> > > So arguably that last op, splice_read from a perf fd is fairly > pointless and we could dis-allow that. How about something like the > below? > > --- > kernel/events/core.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/kernel/events/core.c b/kernel/events/core.c > index 04989fb769f0..fd03f3082ee3 100644 > --- a/kernel/events/core.c > +++ b/kernel/events/core.c > @@ -5468,6 +5468,13 @@ static int perf_fasync(int fd, struct file *filp, int on) > return 0; > } > > +static ssize_t perf_splice_read(struct file *file, loff_t *ppos, > + struct pipe_inode_info *pope, size_t len, > + unsigned int flags) > +{ > + return -EOPNOTSUPP; > +} > + > static const struct file_operations perf_fops = { > .llseek = no_llseek, > .release = perf_release, > @@ -5477,6 +5484,7 @@ static int perf_fasync(int fd, struct file *filp, int on) > .compat_ioctl = perf_compat_ioctl, > .mmap = perf_mmap, > .fasync = perf_fasync, > + .splice_read = perf_splice_read, > }; Another perf deadlock that involves splice: https://groups.google.com/d/msg/syzkaller-bugs/vVy6Zj3wPxo/6oj5U6WiAwAJ ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: possible deadlock in perf_event_ctx_lock_nested 2018-02-12 15:04 ` Dmitry Vyukov @ 2018-02-14 14:00 ` Dmitry Vyukov 0 siblings, 0 replies; 5+ messages in thread From: Dmitry Vyukov @ 2018-02-14 14:00 UTC (permalink / raw) To: Peter Zijlstra Cc: syzbot, Arnaldo Carvalho de Melo, Alexander Shishkin, LKML, Ingo Molnar, syzkaller-bugs, Thomas Gleixner, Steven Rostedt, Al Viro On Mon, Feb 12, 2018 at 4:04 PM, Dmitry Vyukov <dvyukov@google.com> wrote: >>> > ====================================================== >>> > WARNING: possible circular locking dependency detected >>> > 4.13.0-next-20170911+ #19 Not tainted >>> > ------------------------------------------------------ >>> > syz-executor2/12380 is trying to acquire lock: >>> > (&ctx->mutex){+.+.}, at: [<ffffffff8180923c>] >>> > perf_event_ctx_lock_nested+0x1dc/0x3c0 kernel/events/core.c:1210 >>> > >>> > but task is already holding lock: >>> > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock_nested >>> > fs/pipe.c:66 [inline] >>> > (&pipe->mutex/1){+.+.}, at: [<ffffffff81ac0fa6>] pipe_lock+0x56/0x70 >>> > fs/pipe.c:74 >>> > >>> > which lock already depends on the new lock. >>> >>> >>> ARRGH!! >>> >>> that translates like the below, which is an absolute maze and requires >>> at least 5 concurrent callstacks, possibly more. >>> >>> We already had a lot of fun with hotplug-perf-ftrace, but the below >>> contains more. Let me try and page that previous crap back. >>> >>> >>> >>> perf_ioctl() >>> #0 perf_event_ctx_lock() [ctx->mutex] >>> perf_event_set_filter >>> #1 ftrace_profile_set_filter [event_mutex] >>> >>> >>> >>> >>> sys_perf_event_open >>> ... >>> perf_trace_init >>> #1 mutex_lock [event_mutex] >>> trace_event_reg >>> tracepoint_probe_register >>> #2 mutex_lock() [tracepoints_mutex] >>> tracepoint_add_func() >>> #3 static_key_slow_inc() [cpuhotplug_lock] >>> >>> >>> >>> >>> >>> cpuhp_setup_state_nocalls >>> #3 cpus_read_lock [cpuhotplug_lock] >>> __cpuhp_setup_state_cpuslocked >>> #4 mutex_lock [cpuhp_state_mutex] >>> cpuhp_issue_call >>> #5 cpuhp_invoke_ap_callback() [cpuhp_state] >>> >>> >>> #5 cpuhp_invoke_callback [cpuhp_state] >>> ... >>> devtmpfs_create_node >>> #6 wait_for_completion() [&req.done] >>> >>> devtmpfsd >>> handle_create >>> #7 filename_create [sb_writers] >>> #6 complete [&req.done] >>> >>> >>> >>> >>> >>> >>> do_splice >>> #7 file_start_write() [sb_writers] >>> do_splice_from >>> iter_file_splice_write >>> #8 pipe_lock [pipe->mutex] >>> >>> >>> >>> >>> >>> do_splice >>> #8 pipe_lock [pipe->mutex] >>> do_splice_to >>> ... >>> #0 perf_read() [ctx->mutex] >>> >> >> So arguably that last op, splice_read from a perf fd is fairly >> pointless and we could dis-allow that. How about something like the >> below? >> >> --- >> kernel/events/core.c | 8 ++++++++ >> 1 file changed, 8 insertions(+) >> >> diff --git a/kernel/events/core.c b/kernel/events/core.c >> index 04989fb769f0..fd03f3082ee3 100644 >> --- a/kernel/events/core.c >> +++ b/kernel/events/core.c >> @@ -5468,6 +5468,13 @@ static int perf_fasync(int fd, struct file *filp, int on) >> return 0; >> } >> >> +static ssize_t perf_splice_read(struct file *file, loff_t *ppos, >> + struct pipe_inode_info *pope, size_t len, >> + unsigned int flags) >> +{ >> + return -EOPNOTSUPP; >> +} >> + >> static const struct file_operations perf_fops = { >> .llseek = no_llseek, >> .release = perf_release, >> @@ -5477,6 +5484,7 @@ static int perf_fasync(int fd, struct file *filp, int on) >> .compat_ioctl = perf_compat_ioctl, >> .mmap = perf_mmap, >> .fasync = perf_fasync, >> + .splice_read = perf_splice_read, >> }; > > > Another perf deadlock that involves splice: > https://groups.google.com/d/msg/syzkaller-bugs/vVy6Zj3wPxo/6oj5U6WiAwAJ Peter, What's the status of this? Is your patch still relevant? ^ permalink raw reply [flat|nested] 5+ messages in thread
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2017-10-27 8:31 ` possible deadlock in perf_event_ctx_lock_nested Dmitry Vyukov
2017-10-27 15:11 ` Peter Zijlstra
2017-10-27 15:33 ` Peter Zijlstra
2018-02-12 15:04 ` Dmitry Vyukov
2018-02-14 14:00 ` Dmitry Vyukov
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