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-386-4,10.128.0.18' (ECDSA) to the list of known hosts. 2017/09/29 08:04:42 parsed 1 programs 2017/09/29 08:04:42 executed programs: 0 2017/09/29 08:04:47 executed programs: 83 syzkaller login: [ 34.261885] [ 34.263556] ====================================================== [ 34.269836] WARNING: possible circular locking dependency detected [ 34.276122] 4.14.0-rc2+ #16 Not tainted [ 34.280065] ------------------------------------------------------ [ 34.286352] syz-executor0/3486 is trying to acquire lock: [ 34.291855] (event_mutex){+.+.}, at: [] perf_trace_destroy+0x28/0x100 [ 34.300068] [ 34.300068] but task is already holding lock: [ 34.306005] (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 34.314032] [ 34.314032] which lock already depends on the new lock. [ 34.314032] [ 34.322310] [ 34.322310] the existing dependency chain (in reverse order) is: [ 34.329891] [ 34.329891] -> #7 (&mm->mmap_sem){++++}: [ 34.335400] __lock_acquire+0x328f/0x4620 [ 34.340036] lock_acquire+0x1d5/0x580 [ 34.344327] __might_fault+0x13a/0x1d0 [ 34.348701] _copy_to_user+0x2c/0xc0 [ 34.352901] filldir+0x1a7/0x320 [ 34.356755] dcache_readdir+0x12d/0x5e0 [ 34.361215] iterate_dir+0x4b2/0x5d0 [ 34.365501] SyS_getdents+0x225/0x450 [ 34.369788] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.375028] [ 34.375028] -> #6 (&sb->s_type->i_mutex_key#5){++++}: [ 34.381672] down_write+0x87/0x120 [ 34.385701] handle_create+0x30c/0x760 [ 34.390072] devtmpfsd+0x3b4/0x4b0 [ 34.394098] kthread+0x39c/0x470 [ 34.397948] ret_from_fork+0x2a/0x40 [ 34.402145] [ 34.402145] -> #5 ((complete)&req.done){+.+.}: [ 34.408177] __lock_acquire+0x328f/0x4620 [ 34.412811] lock_acquire+0x1d5/0x580 [ 34.417099] wait_for_completion+0xcb/0x7b0 [ 34.421914] devtmpfs_create_node+0x32b/0x4a0 [ 34.426895] device_add+0x120f/0x1640 [ 34.431180] device_create_groups_vargs+0x1f3/0x250 [ 34.436679] device_create+0xda/0x110 [ 34.440966] msr_device_create+0x26/0x40 [ 34.445514] cpuhp_invoke_callback+0x256/0x14d0 [ 34.450665] cpuhp_thread_fun+0x265/0x520 [ 34.455298] smpboot_thread_fn+0x450/0x7c0 [ 34.460018] kthread+0x39c/0x470 [ 34.463870] ret_from_fork+0x2a/0x40 [ 34.468065] [ 34.468065] -> #4 (cpuhp_state){+.+.}: [ 34.473411] __lock_acquire+0x328f/0x4620 [ 34.478042] lock_acquire+0x1d5/0x580 [ 34.482325] cpuhp_issue_call+0x1a2/0x3e0 [ 34.486956] __cpuhp_setup_state_cpuslocked+0x2cc/0x5f0 [ 34.492802] __cpuhp_setup_state+0xb0/0x140 [ 34.497617] page_writeback_init+0x4d/0x71 [ 34.502338] pagecache_init+0x48/0x4f [ 34.506624] start_kernel+0x6c1/0x754 [ 34.510909] x86_64_start_reservations+0x2a/0x2c [ 34.516154] x86_64_start_kernel+0x77/0x7a [ 34.520874] verify_cpu+0x0/0xfb [ 34.524722] [ 34.524722] -> #3 (cpuhp_state_mutex){+.+.}: [ 34.530576] __lock_acquire+0x328f/0x4620 [ 34.535208] lock_acquire+0x1d5/0x580 [ 34.539492] __mutex_lock+0x16f/0x19d0 [ 34.543871] mutex_lock_nested+0x16/0x20 [ 34.548415] __cpuhp_setup_state_cpuslocked+0x5b/0x5f0 [ 34.554175] __cpuhp_setup_state+0xb0/0x140 [ 34.558982] kvm_guest_init+0x1f3/0x20f [ 34.563446] setup_arch+0x1879/0x1a93 [ 34.567739] start_kernel+0xa5/0x754 [ 34.571943] x86_64_start_reservations+0x2a/0x2c [ 34.577183] x86_64_start_kernel+0x77/0x7a [ 34.581903] verify_cpu+0x0/0xfb [ 34.585754] [ 34.585754] -> #2 (cpu_hotplug_lock.rw_sem){++++}: [ 34.592146] __lock_acquire+0x328f/0x4620 [ 34.596790] lock_acquire+0x1d5/0x580 [ 34.601080] cpus_read_lock+0x42/0x90 [ 34.605366] static_key_slow_inc+0x9d/0x3c0 [ 34.610184] tracepoint_probe_register_prio+0x80d/0x9a0 [ 34.616033] tracepoint_probe_register+0x2a/0x40 [ 34.621275] trace_event_reg+0x167/0x320 [ 34.625830] perf_trace_init+0x4ef/0xab0 [ 34.630374] perf_tp_event_init+0x7d/0xf0 [ 34.635005] perf_try_init_event+0xc9/0x1f0 [ 34.639810] perf_event_alloc+0x1c5b/0x2a00 [ 34.644614] SYSC_perf_event_open+0x84e/0x2e00 [ 34.649680] SyS_perf_event_open+0x39/0x50 [ 34.654398] do_fast_syscall_32+0x3f2/0xf05 [ 34.659206] entry_SYSENTER_compat+0x51/0x60 [ 34.664095] [ 34.664095] -> #1 (tracepoints_mutex){+.+.}: [ 34.669954] __lock_acquire+0x328f/0x4620 [ 34.674586] lock_acquire+0x1d5/0x580 [ 34.678870] __mutex_lock+0x16f/0x19d0 [ 34.683240] mutex_lock_nested+0x16/0x20 [ 34.687785] tracepoint_probe_register_prio+0xa0/0x9a0 [ 34.693543] tracepoint_probe_register+0x2a/0x40 [ 34.698785] trace_event_reg+0x167/0x320 [ 34.703431] perf_trace_init+0x4ef/0xab0 [ 34.707975] perf_tp_event_init+0x7d/0xf0 [ 34.712606] perf_try_init_event+0xc9/0x1f0 [ 34.717411] perf_event_alloc+0x1c5b/0x2a00 [ 34.722215] SYSC_perf_event_open+0x84e/0x2e00 [ 34.727281] SyS_perf_event_open+0x39/0x50 [ 34.732000] do_fast_syscall_32+0x3f2/0xf05 [ 34.736805] entry_SYSENTER_compat+0x51/0x60 [ 34.741695] [ 34.741695] -> #0 (event_mutex){+.+.}: [ 34.747028] check_prev_add+0x865/0x1520 [ 34.751572] __lock_acquire+0x328f/0x4620 [ 34.756206] lock_acquire+0x1d5/0x580 [ 34.760491] __mutex_lock+0x16f/0x19d0 [ 34.764863] mutex_lock_nested+0x16/0x20 [ 34.769409] perf_trace_destroy+0x28/0x100 [ 34.774129] tp_perf_event_destroy+0x15/0x20 [ 34.779023] _free_event+0x41d/0x1170 [ 34.783308] put_event+0x24/0x30 [ 34.787157] perf_mmap_close+0x60d/0xf90 [ 34.791704] remove_vma+0xb4/0x1b0 [ 34.795737] do_munmap+0x82a/0xdf0 [ 34.799768] mmap_region+0x59e/0x15a0 [ 34.804051] do_mmap+0x6a1/0xd50 [ 34.807912] vm_mmap_pgoff+0x1de/0x280 [ 34.812282] SyS_mmap_pgoff+0x23b/0x5f0 [ 34.816747] do_fast_syscall_32+0x3f2/0xf05 [ 34.821552] entry_SYSENTER_compat+0x51/0x60 [ 34.826442] [ 34.826442] other info that might help us debug this: [ 34.826442] [ 34.834546] Chain exists of: [ 34.834546] event_mutex --> &sb->s_type->i_mutex_key#5 --> &mm->mmap_sem [ 34.834546] [ 34.845873] Possible unsafe locking scenario: [ 34.845873] [ 34.851891] CPU0 CPU1 [ 34.856518] ---- ---- [ 34.861146] lock(&mm->mmap_sem); [ 34.864648] lock(&sb->s_type->i_mutex_key#5); [ 34.871797] lock(&mm->mmap_sem); [ 34.877817] lock(event_mutex); [ 34.881155] [ 34.881155] *** DEADLOCK *** [ 34.881155] [ 34.887176] 1 lock held by syz-executor0/3486: [ 34.891719] #0: (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 34.900179] [ 34.900179] stack backtrace: [ 34.904647] CPU: 0 PID: 3486 Comm: syz-executor0 Not tainted 4.14.0-rc2+ #16 [ 34.911793] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.921109] Call Trace: [ 34.923676] dump_stack+0x194/0x257 [ 34.927267] ? arch_local_irq_restore+0x53/0x53 [ 34.931906] print_circular_bug+0x503/0x710 [ 34.936192] ? print_circular_bug_entry+0xb0/0xb0 [ 34.940998] ? __unwind_start+0x169/0x330 [ 34.945111] ? __kernel_text_address+0xd/0x40 [ 34.949567] ? unwind_get_return_address+0x61/0xa0 [ 34.954459] check_prev_add+0x865/0x1520 [ 34.958482] ? copy_trace+0x1d0/0x1d0 [ 34.962247] ? check_usage+0xb70/0xb70 [ 34.966100] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 34.971946] ? hlock_class+0x140/0x140 [ 34.975796] ? copy_trace+0x1d0/0x1d0 [ 34.979560] __lock_acquire+0x328f/0x4620 [ 34.983678] ? __lock_acquire+0x328f/0x4620 [ 34.987968] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 34.992951] ? copy_trace+0x1d0/0x1d0 [ 34.996716] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 35.001878] ? __unwind_start+0x169/0x330 [ 35.005990] ? __kernel_text_address+0xd/0x40 [ 35.010448] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 35.015429] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 35.020407] ? unwind_dump+0x4c0/0x4c0 [ 35.024259] ? unwind_dump+0x4c0/0x4c0 [ 35.028112] ? mmap_region+0x59e/0x15a0 [ 35.032049] ? __unwind_start+0x169/0x330 [ 35.036160] ? __kernel_text_address+0xd/0x40 [ 35.040618] ? unwind_get_return_address+0x61/0xa0 [ 35.045512] ? __save_stack_trace+0x61/0xd0 [ 35.049798] ? remove_vma+0xb4/0x1b0 [ 35.053476] ? save_stack_trace+0x16/0x20 [ 35.057589] ? __lock_acquire+0x20fd/0x4620 [ 35.061873] ? __unwind_start+0x169/0x330 [ 35.065982] ? __kernel_text_address+0xd/0x40 [ 35.070440] ? unwind_get_return_address+0x61/0xa0 [ 35.075332] ? check_noncircular+0x20/0x20 [ 35.079530] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 35.084692] ? mmap_region+0x59e/0x15a0 [ 35.088631] ? __lock_acquire+0x20fd/0x4620 [ 35.092926] ? mark_held_locks+0xb2/0x100 [ 35.097039] lock_acquire+0x1d5/0x580 [ 35.100804] ? perf_trace_destroy+0x28/0x100 [ 35.105177] ? finish_task_switch+0x1d3/0x740 [ 35.109638] ? lock_release+0xd70/0xd70 [ 35.113575] ? check_same_owner+0x320/0x320 [ 35.117860] ? preempt_notifier_dec+0x20/0x20 [ 35.122321] ? __might_sleep+0x95/0x190 [ 35.126259] ? perf_trace_destroy+0x28/0x100 [ 35.130631] __mutex_lock+0x16f/0x19d0 [ 35.134485] ? perf_trace_destroy+0x28/0x100 [ 35.138857] ? __sched_text_start+0x8/0x8 [ 35.142966] ? perf_trace_destroy+0x28/0x100 [ 35.147336] ? check_noncircular+0x20/0x20 [ 35.151536] ? mutex_lock_io_nested+0x1880/0x1880 [ 35.156341] ? lock_acquire+0x1d5/0x580 [ 35.160293] ? print_usage_bug+0x480/0x480 [ 35.164493] ? find_held_lock+0x39/0x1d0 [ 35.168517] ? check_noncircular+0x20/0x20 [ 35.172717] ? lock_downgrade+0x990/0x990 [ 35.176830] ? __mutex_lock+0x16f/0x19d0 [ 35.180863] ? __wake_up_common_lock+0x190/0x310 [ 35.185582] ? find_held_lock+0x39/0x1d0 [ 35.189607] ? check_noncircular+0x20/0x20 [ 35.193808] ? perf_addr_filters_splice+0x18f/0x810 [ 35.198788] ? lock_downgrade+0x990/0x990 [ 35.202902] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 35.207969] ? free_filters_list+0x2f0/0x2f0 [ 35.212342] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 35.217323] ? trace_hardirqs_on+0xd/0x10 [ 35.221436] ? __lock_is_held+0xbc/0x140 [ 35.225463] mutex_lock_nested+0x16/0x20 [ 35.229488] ? mutex_lock_nested+0x16/0x20 [ 35.233687] perf_trace_destroy+0x28/0x100 [ 35.237888] ? perf_tp_event_init+0xf0/0xf0 [ 35.242172] tp_perf_event_destroy+0x15/0x20 [ 35.246545] _free_event+0x41d/0x1170 [ 35.250941] ? ring_buffer_attach+0x830/0x830 [ 35.255403] ? wait_for_completion+0x7b0/0x7b0 [ 35.259950] ? ring_buffer_put+0x140/0x140