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-mmots-kasan-gce-9,10.128.0.13' (ECDSA) to the list of known hosts. 2017/09/17 00:38:46 parsed 1 programs 2017/09/17 00:38:46 executed programs: 0 syzkaller login: [ 39.947629] [ 39.949277] ====================================================== [ 39.955557] WARNING: possible circular locking dependency detected [ 39.961837] 4.13.0-mm1+ #7 Not tainted [ 39.965684] ------------------------------------------------------ [ 39.971963] syz-executor0/3002 is trying to acquire lock: [ 39.977459] (event_mutex){+.+.}, at: [] perf_trace_destroy+0x28/0x100 [ 39.985657] [ 39.985657] but task is already holding lock: [ 39.991588] (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 39.999609] [ 39.999609] which lock already depends on the new lock. [ 39.999609] [ 40.007886] [ 40.007886] the existing dependency chain (in reverse order) is: [ 40.015466] [ 40.015466] -> #7 (&mm->mmap_sem){++++}: [ 40.020975] __lock_acquire+0x328f/0x4620 [ 40.025604] lock_acquire+0x1d5/0x580 [ 40.029887] __might_fault+0x13a/0x1d0 [ 40.034257] _copy_to_user+0x2c/0xc0 [ 40.038455] filldir+0x1a7/0x320 [ 40.042304] dcache_readdir+0x12d/0x5e0 [ 40.046758] iterate_dir+0x4b2/0x5d0 [ 40.050955] SyS_getdents+0x225/0x450 [ 40.055240] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 40.060475] [ 40.060475] -> #6 (&sb->s_type->i_mutex_key#5){++++}: [ 40.067110] down_write+0x87/0x120 [ 40.071135] handle_create+0x30c/0x760 [ 40.075504] devtmpfsd+0x3eb/0x520 [ 40.079527] kthread+0x39c/0x470 [ 40.083378] ret_from_fork+0x2a/0x40 [ 40.087572] [ 40.087572] -> #5 ((complete)&req.done){+.+.}: [ 40.093598] __lock_acquire+0x328f/0x4620 [ 40.098227] lock_acquire+0x1d5/0x580 [ 40.102509] wait_for_completion+0xc8/0x770 [ 40.107314] devtmpfs_create_node+0x32b/0x4a0 [ 40.112293] device_add+0x120f/0x1640 [ 40.116575] device_create_groups_vargs+0x1f3/0x250 [ 40.122072] device_create+0xda/0x110 [ 40.126358] msr_device_create+0x26/0x40 [ 40.130903] cpuhp_invoke_callback+0x256/0x14d0 [ 40.136059] cpuhp_thread_fun+0x265/0x520 [ 40.140688] smpboot_thread_fn+0x489/0x850 [ 40.145404] kthread+0x39c/0x470 [ 40.149252] ret_from_fork+0x2a/0x40 [ 40.153445] [ 40.153445] -> #4 (cpuhp_state){+.+.}: [ 40.158777] __lock_acquire+0x328f/0x4620 [ 40.163407] lock_acquire+0x1d5/0x580 [ 40.167690] cpuhp_issue_call+0x1a2/0x3e0 [ 40.172322] __cpuhp_setup_state_cpuslocked+0x2d6/0x5f0 [ 40.178168] __cpuhp_setup_state+0xb0/0x140 [ 40.182975] page_writeback_init+0x4d/0x71 [ 40.187691] pagecache_init+0x48/0x4f [ 40.191978] start_kernel+0x6c1/0x754 [ 40.196262] x86_64_start_reservations+0x2a/0x2c [ 40.201502] x86_64_start_kernel+0x77/0x7a [ 40.206222] verify_cpu+0x0/0xfb [ 40.210070] [ 40.210070] -> #3 (cpuhp_state_mutex){+.+.}: [ 40.215924] __lock_acquire+0x328f/0x4620 [ 40.220555] lock_acquire+0x1d5/0x580 [ 40.224838] __mutex_lock+0x16f/0x1870 [ 40.229207] mutex_lock_nested+0x16/0x20 [ 40.233750] __cpuhp_setup_state_cpuslocked+0x5b/0x5f0 [ 40.239508] __cpuhp_setup_state+0xb0/0x140 [ 40.244312] kvm_guest_init+0x1f3/0x20f [ 40.248769] setup_arch+0x1879/0x1a93 [ 40.253054] start_kernel+0xa5/0x754 [ 40.257252] x86_64_start_reservations+0x2a/0x2c [ 40.262491] x86_64_start_kernel+0x77/0x7a [ 40.267207] verify_cpu+0x0/0xfb [ 40.271055] [ 40.271055] -> #2 (cpu_hotplug_lock.rw_sem){++++}: [ 40.277427] __lock_acquire+0x328f/0x4620 [ 40.282057] lock_acquire+0x1d5/0x580 [ 40.286342] cpus_read_lock+0x42/0x90 [ 40.290627] static_key_slow_inc+0x9d/0x3c0 [ 40.295433] tracepoint_probe_register_prio+0x80d/0x9a0 [ 40.301277] tracepoint_probe_register+0x2a/0x40 [ 40.306514] trace_event_reg+0x167/0x320 [ 40.311058] perf_trace_init+0x4f9/0xab0 [ 40.315602] perf_tp_event_init+0x7d/0xf0 [ 40.320237] perf_try_init_event+0xc9/0x1f0 [ 40.325043] perf_event_alloc+0x1c5b/0x2a00 [ 40.329847] SYSC_perf_event_open+0x84e/0x2e00 [ 40.334911] SyS_perf_event_open+0x39/0x50 [ 40.339628] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 40.344862] [ 40.344862] -> #1 (tracepoints_mutex){+.+.}: [ 40.350718] __lock_acquire+0x328f/0x4620 [ 40.355348] lock_acquire+0x1d5/0x580 [ 40.359632] __mutex_lock+0x16f/0x1870 [ 40.364001] mutex_lock_nested+0x16/0x20 [ 40.368547] tracepoint_probe_register_prio+0xa0/0x9a0 [ 40.374306] tracepoint_probe_register+0x2a/0x40 [ 40.379548] trace_event_reg+0x167/0x320 [ 40.384092] perf_trace_init+0x4f9/0xab0 [ 40.388634] perf_tp_event_init+0x7d/0xf0 [ 40.393263] perf_try_init_event+0xc9/0x1f0 [ 40.398067] perf_event_alloc+0x1c5b/0x2a00 [ 40.402870] SYSC_perf_event_open+0x84e/0x2e00 [ 40.407933] SyS_perf_event_open+0x39/0x50 [ 40.412649] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 40.417883] [ 40.417883] -> #0 (event_mutex){+.+.}: [ 40.423216] check_prev_add+0x865/0x1520 [ 40.427759] __lock_acquire+0x328f/0x4620 [ 40.432389] lock_acquire+0x1d5/0x580 [ 40.436671] __mutex_lock+0x16f/0x1870 [ 40.441040] mutex_lock_nested+0x16/0x20 [ 40.445583] perf_trace_destroy+0x28/0x100 [ 40.450302] tp_perf_event_destroy+0x15/0x20 [ 40.455192] _free_event+0x401/0x1130 [ 40.459476] put_event+0x24/0x30 [ 40.463326] perf_mmap_close+0x60d/0xf90 [ 40.467869] remove_vma+0xb4/0x1b0 [ 40.471892] do_munmap+0x82a/0xdf0 [ 40.475913] mmap_region+0x59e/0x15a0 [ 40.480196] do_mmap+0x6a1/0xd50 [ 40.484048] vm_mmap_pgoff+0x1de/0x280 [ 40.488419] SyS_mmap_pgoff+0x23b/0x5f0 [ 40.492876] SyS_mmap+0x16/0x20 [ 40.496638] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 40.501873] [ 40.501873] other info that might help us debug this: [ 40.501873] [ 40.509976] Chain exists of: [ 40.509976] event_mutex --> &sb->s_type->i_mutex_key#5 --> &mm->mmap_sem [ 40.509976] [ 40.521298] Possible unsafe locking scenario: [ 40.521298] [ 40.527316] CPU0 CPU1 [ 40.531955] ---- ---- [ 40.536584] lock(&mm->mmap_sem); [ 40.540086] lock(&sb->s_type->i_mutex_key#5); [ 40.547234] lock(&mm->mmap_sem); [ 40.553252] lock(event_mutex); [ 40.556579] [ 40.556579] *** DEADLOCK *** [ 40.556579] [ 40.562598] 1 lock held by syz-executor0/3002: [ 40.567139] #0: (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 40.575594] [ 40.575594] stack backtrace: [ 40.580054] CPU: 1 PID: 3002 Comm: syz-executor0 Not tainted 4.13.0-mm1+ #7 [ 40.587113] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 40.596430] Call Trace: [ 40.598988] dump_stack+0x194/0x257 [ 40.602579] ? arch_local_irq_restore+0x53/0x53 [ 40.607216] print_circular_bug+0x503/0x710 [ 40.611502] ? print_circular_bug_entry+0xb0/0xb0 [ 40.616308] ? __unwind_start+0x169/0x330 [ 40.620421] check_prev_add+0x865/0x1520 [ 40.624448] ? copy_trace+0x1d0/0x1d0 [ 40.628213] ? check_usage+0xb70/0xb70 [ 40.632066] ? hlock_class+0x140/0x140 [ 40.635919] ? copy_trace+0x1d0/0x1d0 [ 40.639683] __lock_acquire+0x328f/0x4620 [ 40.643798] ? __lock_acquire+0x328f/0x4620 [ 40.648085] ? copy_trace+0x1d0/0x1d0 [ 40.651851] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 40.657003] ? __unwind_start+0x169/0x330 [ 40.661112] ? unwind_get_return_address+0x61/0xa0 [ 40.666007] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 40.671852] ? do_munmap+0x82a/0xdf0 [ 40.675541] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 40.681388] ? mmap_region+0x59e/0x15a0 [ 40.685324] ? check_noncircular+0x20/0x20 [ 40.689520] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 40.694502] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 40.699481] ? unwind_dump+0x4c0/0x4c0 [ 40.703332] ? unwind_dump+0x4c0/0x4c0 [ 40.707181] ? unwind_dump+0x4c0/0x4c0 [ 40.711031] ? __unwind_start+0x169/0x330 [ 40.715142] ? unwind_get_return_address+0x61/0xa0 [ 40.720035] ? __save_stack_trace+0x61/0xd0 [ 40.724320] ? check_noncircular+0x20/0x20 [ 40.728520] ? do_munmap+0x82a/0xdf0 [ 40.732196] ? save_stack_trace+0x16/0x20 [ 40.736309] ? __lock_acquire+0x20fd/0x4620 [ 40.740593] ? save_stack_trace+0x16/0x20 [ 40.744703] ? __lock_acquire+0x20fd/0x4620 [ 40.748990] lock_acquire+0x1d5/0x580 [ 40.752754] ? perf_trace_destroy+0x28/0x100 [ 40.757127] ? lock_release+0xd70/0xd70 [ 40.761068] ? check_same_owner+0x320/0x320 [ 40.765352] ? preempt_notifier_dec+0x20/0x20 [ 40.769812] ? __might_sleep+0x95/0x190 [ 40.773748] ? perf_trace_destroy+0x28/0x100 [ 40.778118] __mutex_lock+0x16f/0x1870 [ 40.781967] ? perf_trace_destroy+0x28/0x100 [ 40.786338] ? __sched_text_start+0x8/0x8 [ 40.790448] ? perf_trace_destroy+0x28/0x100 [ 40.794818] ? mutex_lock_io_nested+0x1740/0x1740 [ 40.799632] ? lock_acquire+0x1d5/0x580 [ 40.803571] ? perf_mmap_close+0x5cb/0xf90 [ 40.807771] ? check_same_owner+0x320/0x320 [ 40.812056] ? check_noncircular+0x20/0x20 [ 40.816251] ? perf_mmap_close+0x33f/0xf90 [ 40.820448] ? check_noncircular+0x20/0x20 [ 40.824646] ? check_noncircular+0x20/0x20 [ 40.828844] ? print_usage_bug+0x480/0x480 [ 40.833040] ? __mutex_lock+0x16f/0x1870 [ 40.837062] ? perf_mmap_close+0x5cb/0xf90 [ 40.841261] ? print_usage_bug+0x480/0x480 [ 40.845462] ? find_held_lock+0x39/0x1d0 [ 40.849484] ? check_noncircular+0x20/0x20 [ 40.853681] ? perf_addr_filters_splice+0x18f/0x810 [ 40.858658] ? lock_downgrade+0x990/0x990 [ 40.862768] ? free_filters_list+0x2f0/0x2f0 [ 40.867141] ? __wake_up+0x1e/0x50 [ 40.870645] ? __lock_is_held+0xbc/0x140 [ 40.874668] mutex_lock_nested+0x16/0x20 [ 40.878692] ? mutex_lock_nested+0x16/0x20 [ 40.882889] perf_trace_destroy+0x28/0x100 [ 40.887086] ? perf_tp_event_init+0xf0/0xf0 [ 40.891369] tp_perf_event_destroy+0x15/0x20 [ 40.895740] _free_event+0x401/0x1130 [ 40.899506] ? ring_buffer_attach+0x830/0x830 [ 40.903963] ? wait_for_completion+0x770/0x770 [ 40.908507] ? ring_buffer_put+0x140/0x140 [ 40.912706] ? lock_release+0xd70/0xd70 [ 40.916642] ? atomic_dec_and_mutex_lock+0x112/0x150 [ 40.921706] ? atomic_dec_and_mutex_lock+0x112/0x150 [ 40.926772] put_event+0x24/0x30 [ 40.930100] perf_mmap_close+0x60d/0xf90 [ 40.934126] ? perf_compat_ioctl+0x70/0x70 [ 40.938323] ? save_stack_trace+0x16/0x20 [ 40.942432] ? check_noncircular+0x20/0x20 [ 40.946630] ? remove_vma+0x162/0x1b0