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-3,10.128.0.47' (ECDSA) to the list of known hosts. 2017/09/18 00:35:15 parsed 1 programs 2017/09/18 00:35:15 executed programs: 0 syzkaller login: [ 44.790808] [ 44.792475] ====================================================== [ 44.798755] WARNING: possible circular locking dependency detected [ 44.805036] 4.13.0-mm1+ #7 Not tainted [ 44.808883] ------------------------------------------------------ [ 44.815162] syz-executor0/3135 is trying to acquire lock: [ 44.820659] (event_mutex){+.+.}, at: [] perf_trace_destroy+0x28/0x100 [ 44.828865] [ 44.828865] but task is already holding lock: [ 44.834798] (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 44.842819] [ 44.842819] which lock already depends on the new lock. [ 44.842819] [ 44.851100] [ 44.851100] the existing dependency chain (in reverse order) is: [ 44.858709] [ 44.858709] -> #7 (&mm->mmap_sem){++++}: [ 44.864220] __lock_acquire+0x328f/0x4620 [ 44.868852] lock_acquire+0x1d5/0x580 [ 44.873141] __might_fault+0x13a/0x1d0 [ 44.877512] _copy_to_user+0x2c/0xc0 [ 44.881714] filldir+0x1a7/0x320 [ 44.885567] dcache_readdir+0x12d/0x5e0 [ 44.890025] iterate_dir+0x4b2/0x5d0 [ 44.894221] SyS_getdents+0x225/0x450 [ 44.898509] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 44.903746] [ 44.903746] -> #6 (&sb->s_type->i_mutex_key#5){++++}: [ 44.910384] down_write+0x87/0x120 [ 44.914412] handle_create+0x30c/0x760 [ 44.918783] devtmpfsd+0x3eb/0x520 [ 44.922810] kthread+0x39c/0x470 [ 44.926661] ret_from_fork+0x2a/0x40 [ 44.930856] [ 44.930856] -> #5 ((complete)&req.done){+.+.}: [ 44.936882] __lock_acquire+0x328f/0x4620 [ 44.941516] lock_acquire+0x1d5/0x580 [ 44.945801] wait_for_completion+0xc8/0x770 [ 44.950617] devtmpfs_create_node+0x32b/0x4a0 [ 44.955597] device_add+0x120f/0x1640 [ 44.959884] device_create_groups_vargs+0x1f3/0x250 [ 44.965383] device_create+0xda/0x110 [ 44.969670] msr_device_create+0x26/0x40 [ 44.974217] cpuhp_invoke_callback+0x256/0x14d0 [ 44.979368] cpuhp_thread_fun+0x265/0x520 [ 44.983999] smpboot_thread_fn+0x489/0x850 [ 44.988723] kthread+0x39c/0x470 [ 44.992572] ret_from_fork+0x2a/0x40 [ 44.996769] [ 44.996769] -> #4 (cpuhp_state){+.+.}: [ 45.002101] __lock_acquire+0x328f/0x4620 [ 45.006731] lock_acquire+0x1d5/0x580 [ 45.011016] cpuhp_issue_call+0x1a2/0x3e0 [ 45.015646] __cpuhp_setup_state_cpuslocked+0x2d6/0x5f0 [ 45.021493] __cpuhp_setup_state+0xb0/0x140 [ 45.026300] page_writeback_init+0x4d/0x71 [ 45.031019] pagecache_init+0x48/0x4f [ 45.035306] start_kernel+0x6c1/0x754 [ 45.039591] x86_64_start_reservations+0x2a/0x2c [ 45.044830] x86_64_start_kernel+0x77/0x7a [ 45.049550] verify_cpu+0x0/0xfb [ 45.053397] [ 45.053397] -> #3 (cpuhp_state_mutex){+.+.}: [ 45.059251] __lock_acquire+0x328f/0x4620 [ 45.063882] lock_acquire+0x1d5/0x580 [ 45.068166] __mutex_lock+0x16f/0x1870 [ 45.072535] mutex_lock_nested+0x16/0x20 [ 45.077080] __cpuhp_setup_state_cpuslocked+0x5b/0x5f0 [ 45.082840] __cpuhp_setup_state+0xb0/0x140 [ 45.087645] kvm_guest_init+0x1f3/0x20f [ 45.092102] setup_arch+0x1879/0x1a93 [ 45.096386] start_kernel+0xa5/0x754 [ 45.100582] x86_64_start_reservations+0x2a/0x2c [ 45.105823] x86_64_start_kernel+0x77/0x7a [ 45.110545] verify_cpu+0x0/0xfb [ 45.114391] [ 45.114391] -> #2 (cpu_hotplug_lock.rw_sem){++++}: [ 45.120766] __lock_acquire+0x328f/0x4620 [ 45.125396] lock_acquire+0x1d5/0x580 [ 45.129681] cpus_read_lock+0x42/0x90 [ 45.133966] static_key_slow_inc+0x9d/0x3c0 [ 45.138772] tracepoint_probe_register_prio+0x80d/0x9a0 [ 45.144618] tracepoint_probe_register+0x2a/0x40 [ 45.149857] trace_event_reg+0x167/0x320 [ 45.154401] perf_trace_init+0x4f9/0xab0 [ 45.158947] perf_tp_event_init+0x7d/0xf0 [ 45.163581] perf_try_init_event+0xc9/0x1f0 [ 45.168385] perf_event_alloc+0x1c5b/0x2a00 [ 45.173189] SYSC_perf_event_open+0x84e/0x2e00 [ 45.178259] SyS_perf_event_open+0x39/0x50 [ 45.182980] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 45.188216] [ 45.188216] -> #1 (tracepoints_mutex){+.+.}: [ 45.194070] __lock_acquire+0x328f/0x4620 [ 45.198701] lock_acquire+0x1d5/0x580 [ 45.202984] __mutex_lock+0x16f/0x1870 [ 45.207355] mutex_lock_nested+0x16/0x20 [ 45.211900] tracepoint_probe_register_prio+0xa0/0x9a0 [ 45.217657] tracepoint_probe_register+0x2a/0x40 [ 45.222896] trace_event_reg+0x167/0x320 [ 45.227440] perf_trace_init+0x4f9/0xab0 [ 45.231983] perf_tp_event_init+0x7d/0xf0 [ 45.236614] perf_try_init_event+0xc9/0x1f0 [ 45.241420] perf_event_alloc+0x1c5b/0x2a00 [ 45.246224] SYSC_perf_event_open+0x84e/0x2e00 [ 45.251306] SyS_perf_event_open+0x39/0x50 [ 45.256027] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 45.261265] [ 45.261265] -> #0 (event_mutex){+.+.}: [ 45.266598] check_prev_add+0x865/0x1520 [ 45.271143] __lock_acquire+0x328f/0x4620 [ 45.275775] lock_acquire+0x1d5/0x580 [ 45.280060] __mutex_lock+0x16f/0x1870 [ 45.284432] mutex_lock_nested+0x16/0x20 [ 45.288978] perf_trace_destroy+0x28/0x100 [ 45.293695] tp_perf_event_destroy+0x15/0x20 [ 45.298590] _free_event+0x401/0x1130 [ 45.302874] put_event+0x24/0x30 [ 45.306724] perf_mmap_close+0x60d/0xf90 [ 45.311273] remove_vma+0xb4/0x1b0 [ 45.315296] do_munmap+0x82a/0xdf0 [ 45.319319] mmap_region+0x59e/0x15a0 [ 45.323607] do_mmap+0x6a1/0xd50 [ 45.327457] vm_mmap_pgoff+0x1de/0x280 [ 45.331829] SyS_mmap_pgoff+0x23b/0x5f0 [ 45.336286] SyS_mmap+0x16/0x20 [ 45.340050] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 45.345285] [ 45.345285] other info that might help us debug this: [ 45.345285] [ 45.353388] Chain exists of: [ 45.353388] event_mutex --> &sb->s_type->i_mutex_key#5 --> &mm->mmap_sem [ 45.353388] [ 45.364715] Possible unsafe locking scenario: [ 45.364715] [ 45.370743] CPU0 CPU1 [ 45.375372] ---- ---- [ 45.379999] lock(&mm->mmap_sem); [ 45.383503] lock(&sb->s_type->i_mutex_key#5); [ 45.390655] lock(&mm->mmap_sem); [ 45.396675] lock(event_mutex); [ 45.400007] [ 45.400007] *** DEADLOCK *** [ 45.400007] [ 45.406038] 1 lock held by syz-executor0/3135: [ 45.410580] #0: (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 45.419039] [ 45.419039] stack backtrace: [ 45.423498] CPU: 1 PID: 3135 Comm: syz-executor0 Not tainted 4.13.0-mm1+ #7 [ 45.430563] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.439882] Call Trace: [ 45.442441] dump_stack+0x194/0x257 [ 45.446036] ? arch_local_irq_restore+0x53/0x53 [ 45.450674] print_circular_bug+0x503/0x710 [ 45.454959] ? print_circular_bug_entry+0xb0/0xb0 [ 45.459767] ? __unwind_start+0x169/0x330 [ 45.463882] check_prev_add+0x865/0x1520 [ 45.467909] ? copy_trace+0x1d0/0x1d0 [ 45.471673] ? check_usage+0xb70/0xb70 [ 45.475527] ? hlock_class+0x140/0x140 [ 45.479377] ? copy_trace+0x1d0/0x1d0 [ 45.483154] __lock_acquire+0x328f/0x4620 [ 45.487268] ? __lock_acquire+0x328f/0x4620 [ 45.491553] ? copy_trace+0x1d0/0x1d0 [ 45.495318] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.500471] ? __unwind_start+0x169/0x330 [ 45.504592] ? unwind_get_return_address+0x61/0xa0 [ 45.509485] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 45.515333] ? do_munmap+0x82a/0xdf0 [ 45.519010] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 45.524856] ? mmap_region+0x59e/0x15a0 [ 45.528804] ? check_noncircular+0x20/0x20 [ 45.533011] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 45.537998] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 45.542979] ? unwind_dump+0x4c0/0x4c0 [ 45.546829] ? unwind_dump+0x4c0/0x4c0 [ 45.550680] ? unwind_dump+0x4c0/0x4c0 [ 45.554530] ? __unwind_start+0x169/0x330 [ 45.558641] ? unwind_get_return_address+0x61/0xa0 [ 45.563534] ? __save_stack_trace+0x61/0xd0 [ 45.567821] ? check_noncircular+0x20/0x20 [ 45.572019] ? do_munmap+0x82a/0xdf0 [ 45.575697] ? save_stack_trace+0x16/0x20 [ 45.579811] ? __lock_acquire+0x20fd/0x4620 [ 45.584101] ? save_stack_trace+0x16/0x20 [ 45.588224] ? __lock_acquire+0x20fd/0x4620 [ 45.592515] lock_acquire+0x1d5/0x580 [ 45.596280] ? perf_trace_destroy+0x28/0x100 [ 45.600654] ? lock_release+0xd70/0xd70 [ 45.604591] ? check_same_owner+0x320/0x320 [ 45.608875] ? preempt_notifier_dec+0x20/0x20 [ 45.613335] ? __might_sleep+0x95/0x190 [ 45.617271] ? perf_trace_destroy+0x28/0x100 [ 45.621647] __mutex_lock+0x16f/0x1870 [ 45.625508] ? perf_trace_destroy+0x28/0x100 [ 45.629885] ? __sched_text_start+0x8/0x8 [ 45.633994] ? perf_trace_destroy+0x28/0x100 [ 45.638367] ? mutex_lock_io_nested+0x1740/0x1740 [ 45.643172] ? lock_acquire+0x1d5/0x580 [ 45.647111] ? perf_mmap_close+0x5cb/0xf90 [ 45.651311] ? check_same_owner+0x320/0x320 [ 45.655596] ? check_noncircular+0x20/0x20 [ 45.659793] ? perf_mmap_close+0x33f/0xf90 [ 45.663989] ? check_noncircular+0x20/0x20 [ 45.668693] ? check_noncircular+0x20/0x20 [ 45.672896] ? print_usage_bug+0x480/0x480 [ 45.677093] ? __mutex_lock+0x16f/0x1870 [ 45.681117] ? perf_mmap_close+0x5cb/0xf90 [ 45.685314] ? print_usage_bug+0x480/0x480 [ 45.689514] ? find_held_lock+0x39/0x1d0 [ 45.693540] ? check_noncircular+0x20/0x20 [ 45.697739] ? perf_addr_filters_splice+0x18f/0x810 [ 45.702718] ? lock_downgrade+0x990/0x990 [ 45.706828] ? free_filters_list+0x2f0/0x2f0 [ 45.711201] ? __wake_up+0x1e/0x50 [ 45.714708] ? __lock_is_held+0xbc/0x140 [ 45.718732] mutex_lock_nested+0x16/0x20 [ 45.722754] ? mutex_lock_nested+0x16/0x20 [ 45.726951] perf_trace_destroy+0x28/0x100 [ 45.731148] ? perf_tp_event_init+0xf0/0xf0 [ 45.735431] tp_perf_event_destroy+0x15/0x20 [ 45.739804] _free_event+0x401/0x1130 [ 45.743569] ? ring_buffer_attach+0x830/0x830 [ 45.748028] ? wait_for_completion+0x770/0x770 [ 45.752574] ? ring_buffer_put+0x140/0x140 [ 45.756784] ? lock_release+0xd70/0xd70 [ 45.760722] ? atomic_dec_and_mutex_lock+0x112/0x150 [ 45.765788] ? atomic_dec_and_mutex_lock+0x112/0x150 [ 45.770855] put_event+0x24/0x30 [ 45.774182] perf_mmap_close+0x60d/0xf90 [ 45.778209] ? perf_compat_ioctl+0x70/0x70 [ 45.782406] ? save_stack_trace+0x16/0x20 [ 45.786519] ? check_noncircular+0x20/0x20 [ 45.790718] ? remove_vma+0x162/0x1b0