INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added 'ci-upstream-kasan-gce-386-4,10.128.15.239' (ECDSA) to the list of known hosts. 2017/09/28 11:17:46 parsed 1 programs 2017/09/28 11:17:46 executed programs: 0 syzkaller login: [ 41.101859] [ 41.103506] ====================================================== [ 41.109788] WARNING: possible circular locking dependency detected [ 41.116071] 4.14.0-rc2+ #15 Not tainted [ 41.120007] ------------------------------------------------------ [ 41.126287] syz-executor0/3304 is trying to acquire lock: [ 41.131786] (event_mutex){+.+.}, at: [] perf_trace_destroy+0x28/0x100 [ 41.139988] [ 41.139988] but task is already holding lock: [ 41.145921] (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 41.153945] [ 41.153945] which lock already depends on the new lock. [ 41.153945] [ 41.162224] [ 41.162224] the existing dependency chain (in reverse order) is: [ 41.169892] [ 41.169892] -> #7 (&mm->mmap_sem){++++}: [ 41.175412] __lock_acquire+0x328f/0x4620 [ 41.180042] lock_acquire+0x1d5/0x580 [ 41.184327] __might_fault+0x13a/0x1d0 [ 41.188700] _copy_to_user+0x2c/0xc0 [ 41.192898] filldir+0x1a7/0x320 [ 41.196751] dcache_readdir+0x12d/0x5e0 [ 41.201210] iterate_dir+0x4b2/0x5d0 [ 41.205410] SyS_getdents+0x225/0x450 [ 41.209711] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 41.214949] [ 41.214949] -> #6 (&sb->s_type->i_mutex_key#5){++++}: [ 41.221584] down_write+0x87/0x120 [ 41.225611] handle_create+0x30c/0x760 [ 41.229988] devtmpfsd+0x3b4/0x4b0 [ 41.234018] kthread+0x39c/0x470 [ 41.237872] ret_from_fork+0x2a/0x40 [ 41.242068] [ 41.242068] -> #5 ((complete)&req.done){+.+.}: [ 41.248102] __lock_acquire+0x328f/0x4620 [ 41.252734] lock_acquire+0x1d5/0x580 [ 41.257018] wait_for_completion+0xcb/0x7b0 [ 41.261828] devtmpfs_create_node+0x32b/0x4a0 [ 41.266814] device_add+0x120f/0x1640 [ 41.271101] device_create_groups_vargs+0x1f3/0x250 [ 41.276600] device_create+0xda/0x110 [ 41.280887] msr_device_create+0x26/0x40 [ 41.285436] cpuhp_invoke_callback+0x256/0x14d0 [ 41.290594] cpuhp_thread_fun+0x265/0x520 [ 41.295226] smpboot_thread_fn+0x450/0x7c0 [ 41.299945] kthread+0x39c/0x470 [ 41.303795] ret_from_fork+0x2a/0x40 [ 41.307993] [ 41.307993] -> #4 (cpuhp_state){+.+.}: [ 41.313327] __lock_acquire+0x328f/0x4620 [ 41.317958] lock_acquire+0x1d5/0x580 [ 41.322243] cpuhp_issue_call+0x1a2/0x3e0 [ 41.326875] __cpuhp_setup_state_cpuslocked+0x2cc/0x5f0 [ 41.332731] __cpuhp_setup_state+0xb0/0x140 [ 41.337538] page_writeback_init+0x4d/0x71 [ 41.342259] pagecache_init+0x48/0x4f [ 41.346545] start_kernel+0x6c1/0x754 [ 41.350836] x86_64_start_reservations+0x2a/0x2c [ 41.356073] x86_64_start_kernel+0x77/0x7a [ 41.360794] verify_cpu+0x0/0xfb [ 41.364644] [ 41.364644] -> #3 (cpuhp_state_mutex){+.+.}: [ 41.370495] __lock_acquire+0x328f/0x4620 [ 41.375126] lock_acquire+0x1d5/0x580 [ 41.379410] __mutex_lock+0x16f/0x19d0 [ 41.383780] mutex_lock_nested+0x16/0x20 [ 41.388325] __cpuhp_setup_state_cpuslocked+0x5b/0x5f0 [ 41.394084] __cpuhp_setup_state+0xb0/0x140 [ 41.398899] kvm_guest_init+0x1f3/0x20f [ 41.403358] setup_arch+0x1879/0x1a93 [ 41.407641] start_kernel+0xa5/0x754 [ 41.411840] x86_64_start_reservations+0x2a/0x2c [ 41.417079] x86_64_start_kernel+0x77/0x7a [ 41.421797] verify_cpu+0x0/0xfb [ 41.425645] [ 41.425645] -> #2 (cpu_hotplug_lock.rw_sem){++++}: [ 41.432022] __lock_acquire+0x328f/0x4620 [ 41.436657] lock_acquire+0x1d5/0x580 [ 41.440945] cpus_read_lock+0x42/0x90 [ 41.445231] static_key_slow_inc+0x9d/0x3c0 [ 41.450037] tracepoint_probe_register_prio+0x80d/0x9a0 [ 41.455884] tracepoint_probe_register+0x2a/0x40 [ 41.461123] trace_event_reg+0x167/0x320 [ 41.465666] perf_trace_init+0x4ef/0xab0 [ 41.470211] perf_tp_event_init+0x7d/0xf0 [ 41.474842] perf_try_init_event+0xc9/0x1f0 [ 41.479655] perf_event_alloc+0x1c5b/0x2a00 [ 41.484458] SYSC_perf_event_open+0x84e/0x2e00 [ 41.489523] SyS_perf_event_open+0x39/0x50 [ 41.494245] do_fast_syscall_32+0x3f2/0xf05 [ 41.499054] entry_SYSENTER_compat+0x51/0x60 [ 41.503943] [ 41.503943] -> #1 (tracepoints_mutex){+.+.}: [ 41.509800] __lock_acquire+0x328f/0x4620 [ 41.514430] lock_acquire+0x1d5/0x580 [ 41.518715] __mutex_lock+0x16f/0x19d0 [ 41.523084] mutex_lock_nested+0x16/0x20 [ 41.527627] tracepoint_probe_register_prio+0xa0/0x9a0 [ 41.533388] tracepoint_probe_register+0x2a/0x40 [ 41.538629] trace_event_reg+0x167/0x320 [ 41.543171] perf_trace_init+0x4ef/0xab0 [ 41.547722] perf_tp_event_init+0x7d/0xf0 [ 41.552352] perf_try_init_event+0xc9/0x1f0 [ 41.557155] perf_event_alloc+0x1c5b/0x2a00 [ 41.561967] SYSC_perf_event_open+0x84e/0x2e00 [ 41.567032] SyS_perf_event_open+0x39/0x50 [ 41.571750] do_fast_syscall_32+0x3f2/0xf05 [ 41.576555] entry_SYSENTER_compat+0x51/0x60 [ 41.581443] [ 41.581443] -> #0 (event_mutex){+.+.}: [ 41.586775] check_prev_add+0x865/0x1520 [ 41.591318] __lock_acquire+0x328f/0x4620 [ 41.595952] lock_acquire+0x1d5/0x580 [ 41.600235] __mutex_lock+0x16f/0x19d0 [ 41.604610] mutex_lock_nested+0x16/0x20 [ 41.609154] perf_trace_destroy+0x28/0x100 [ 41.613880] tp_perf_event_destroy+0x15/0x20 [ 41.618769] _free_event+0x41d/0x1170 [ 41.623052] put_event+0x24/0x30 [ 41.626900] perf_mmap_close+0x60d/0xf90 [ 41.631443] remove_vma+0xb4/0x1b0 [ 41.635463] do_munmap+0x82a/0xdf0 [ 41.639484] mmap_region+0x59e/0x15a0 [ 41.643766] do_mmap+0x6a1/0xd50 [ 41.647614] vm_mmap_pgoff+0x1de/0x280 [ 41.651983] SyS_mmap_pgoff+0x23b/0x5f0 [ 41.656439] do_fast_syscall_32+0x3f2/0xf05 [ 41.661245] entry_SYSENTER_compat+0x51/0x60 [ 41.666133] [ 41.666133] other info that might help us debug this: [ 41.666133] [ 41.674235] Chain exists of: [ 41.674235] event_mutex --> &sb->s_type->i_mutex_key#5 --> &mm->mmap_sem [ 41.674235] [ 41.685566] Possible unsafe locking scenario: [ 41.685566] [ 41.691584] CPU0 CPU1 [ 41.696215] ---- ---- [ 41.700842] lock(&mm->mmap_sem); [ 41.704344] lock(&sb->s_type->i_mutex_key#5); [ 41.711494] lock(&mm->mmap_sem); [ 41.717511] lock(event_mutex); [ 41.720838] [ 41.720838] *** DEADLOCK *** [ 41.720838] [ 41.726861] 1 lock held by syz-executor0/3304: [ 41.731402] #0: (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 41.739863] [ 41.739863] stack backtrace: [ 41.744323] CPU: 0 PID: 3304 Comm: syz-executor0 Not tainted 4.14.0-rc2+ #15 [ 41.751469] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.760784] Call Trace: [ 41.763337] dump_stack+0x194/0x257 [ 41.766930] ? arch_local_irq_restore+0x53/0x53 [ 41.771565] print_circular_bug+0x503/0x710 [ 41.775849] ? print_circular_bug_entry+0xb0/0xb0 [ 41.780669] ? __unwind_start+0x169/0x330 [ 41.784787] ? __kernel_text_address+0xd/0x40 [ 41.789272] ? unwind_get_return_address+0x61/0xa0 [ 41.794166] check_prev_add+0x865/0x1520 [ 41.798190] ? copy_trace+0x1d0/0x1d0 [ 41.801960] ? check_usage+0xb70/0xb70 [ 41.805811] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 41.811658] ? hlock_class+0x140/0x140 [ 41.815508] ? copy_trace+0x1d0/0x1d0 [ 41.819274] __lock_acquire+0x328f/0x4620 [ 41.823390] ? __lock_acquire+0x328f/0x4620 [ 41.827683] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 41.832664] ? copy_trace+0x1d0/0x1d0 [ 41.836429] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.841583] ? __unwind_start+0x169/0x330 [ 41.845693] ? __kernel_text_address+0xd/0x40 [ 41.850151] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 41.855130] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 41.860107] ? unwind_dump+0x4c0/0x4c0 [ 41.863962] ? unwind_dump+0x4c0/0x4c0 [ 41.867813] ? mmap_region+0x59e/0x15a0 [ 41.871749] ? __unwind_start+0x169/0x330 [ 41.875858] ? __kernel_text_address+0xd/0x40 [ 41.880315] ? unwind_get_return_address+0x61/0xa0 [ 41.885209] ? __save_stack_trace+0x61/0xd0 [ 41.889493] ? remove_vma+0xb4/0x1b0 [ 41.893168] ? save_stack_trace+0x16/0x20 [ 41.897277] ? __lock_acquire+0x20fd/0x4620 [ 41.901560] ? __unwind_start+0x169/0x330 [ 41.905669] ? __kernel_text_address+0xd/0x40 [ 41.910134] ? unwind_get_return_address+0x61/0xa0 [ 41.915035] ? check_noncircular+0x20/0x20 [ 41.919236] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.924389] ? mmap_region+0x59e/0x15a0 [ 41.928334] ? __lock_acquire+0x20fd/0x4620 [ 41.932632] ? mark_held_locks+0xb2/0x100 [ 41.936746] lock_acquire+0x1d5/0x580 [ 41.940511] ? perf_trace_destroy+0x28/0x100 [ 41.944883] ? finish_task_switch+0x1d3/0x740 [ 41.949343] ? lock_release+0xd70/0xd70 [ 41.953279] ? check_same_owner+0x320/0x320 [ 41.957563] ? preempt_notifier_dec+0x20/0x20 [ 41.962025] ? __might_sleep+0x95/0x190 [ 41.965962] ? perf_trace_destroy+0x28/0x100 [ 41.970351] __mutex_lock+0x16f/0x19d0 [ 41.974203] ? perf_trace_destroy+0x28/0x100 [ 41.978577] ? __sched_text_start+0x8/0x8 [ 41.982689] ? perf_trace_destroy+0x28/0x100 [ 41.987062] ? check_noncircular+0x20/0x20 [ 41.991261] ? mutex_lock_io_nested+0x1880/0x1880 [ 41.996066] ? lock_acquire+0x1d5/0x580 [ 42.000004] ? print_usage_bug+0x480/0x480 [ 42.004203] ? find_held_lock+0x39/0x1d0 [ 42.008225] ? check_noncircular+0x20/0x20 [ 42.012425] ? lock_downgrade+0x990/0x990 [ 42.016541] ? __mutex_lock+0x16f/0x19d0 [ 42.020567] ? __wake_up_common_lock+0x190/0x310 [ 42.025285] ? find_held_lock+0x39/0x1d0 [ 42.029309] ? check_noncircular+0x20/0x20 [ 42.033507] ? perf_addr_filters_splice+0x18f/0x810 [ 42.038486] ? lock_downgrade+0x990/0x990 [ 42.042596] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 42.047670] ? free_filters_list+0x2f0/0x2f0 [ 42.052049] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 42.057026] ? trace_hardirqs_on+0xd/0x10 [ 42.061137] ? __lock_is_held+0xbc/0x140 [ 42.065162] mutex_lock_nested+0x16/0x20 [ 42.069186] ? mutex_lock_nested+0x16/0x20 [ 42.073383] perf_trace_destroy+0x28/0x100 [ 42.077580] ? perf_tp_event_init+0xf0/0xf0 [ 42.081864] tp_perf_event_destroy+0x15/0x20 [ 42.086235] _free_event+0x41d/0x1170 [ 42.089999] ? ring_buffer_attach+0x830/0x830 [ 42.094467] ? wait_for_completion+0x7b0/0x7b0 [ 42.099036] ? ring_buffer_put+0x140/0x140