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-386-4,10.128.0.62' (ECDSA) to the list of known hosts. 2017/09/29 07:52:42 parsed 1 programs 2017/09/29 07:52:42 executed programs: 0 syzkaller login: [ 56.819341] [ 56.820989] ====================================================== [ 56.827268] WARNING: possible circular locking dependency detected [ 56.833548] 4.14.0-rc2+ #16 Not tainted [ 56.837483] ------------------------------------------------------ [ 56.843764] syz-executor0/3173 is trying to acquire lock: [ 56.849271] (event_mutex){+.+.}, at: [] perf_trace_destroy+0x28/0x100 [ 56.857477] [ 56.857477] but task is already holding lock: [ 56.863409] (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 56.871433] [ 56.871433] which lock already depends on the new lock. [ 56.871433] [ 56.879717] [ 56.879717] the existing dependency chain (in reverse order) is: [ 56.887299] [ 56.887299] -> #7 (&mm->mmap_sem){++++}: [ 56.892810] __lock_acquire+0x328f/0x4620 [ 56.897441] lock_acquire+0x1d5/0x580 [ 56.901726] __might_fault+0x13a/0x1d0 [ 56.906098] _copy_to_user+0x2c/0xc0 [ 56.910296] filldir+0x1a7/0x320 [ 56.914148] dcache_readdir+0x12d/0x5e0 [ 56.918607] iterate_dir+0x4b2/0x5d0 [ 56.922803] SyS_getdents+0x225/0x450 [ 56.927099] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 56.932337] [ 56.932337] -> #6 (&sb->s_type->i_mutex_key#5){++++}: [ 56.938974] down_write+0x87/0x120 [ 56.943003] handle_create+0x30c/0x760 [ 56.947374] devtmpfsd+0x3b4/0x4b0 [ 56.951398] kthread+0x39c/0x470 [ 56.955256] ret_from_fork+0x2a/0x40 [ 56.959451] [ 56.959451] -> #5 ((complete)&req.done){+.+.}: [ 56.965476] __lock_acquire+0x328f/0x4620 [ 56.970108] lock_acquire+0x1d5/0x580 [ 56.974391] wait_for_completion+0xcb/0x7b0 [ 56.979195] devtmpfs_create_node+0x32b/0x4a0 [ 56.984179] device_add+0x120f/0x1640 [ 56.988462] device_create_groups_vargs+0x1f3/0x250 [ 56.993962] device_create+0xda/0x110 [ 56.998248] msr_device_create+0x26/0x40 [ 57.002794] cpuhp_invoke_callback+0x256/0x14d0 [ 57.007947] cpuhp_thread_fun+0x265/0x520 [ 57.012588] smpboot_thread_fn+0x450/0x7c0 [ 57.017306] kthread+0x39c/0x470 [ 57.021156] ret_from_fork+0x2a/0x40 [ 57.025351] [ 57.025351] -> #4 (cpuhp_state){+.+.}: [ 57.030681] __lock_acquire+0x328f/0x4620 [ 57.035312] lock_acquire+0x1d5/0x580 [ 57.039606] cpuhp_issue_call+0x1a2/0x3e0 [ 57.044237] __cpuhp_setup_state_cpuslocked+0x2cc/0x5f0 [ 57.050087] __cpuhp_setup_state+0xb0/0x140 [ 57.054905] page_writeback_init+0x4d/0x71 [ 57.059624] pagecache_init+0x48/0x4f [ 57.063909] start_kernel+0x6c1/0x754 [ 57.068192] x86_64_start_reservations+0x2a/0x2c [ 57.073430] x86_64_start_kernel+0x77/0x7a [ 57.078160] verify_cpu+0x0/0xfb [ 57.082011] [ 57.082011] -> #3 (cpuhp_state_mutex){+.+.}: [ 57.087866] __lock_acquire+0x328f/0x4620 [ 57.092495] lock_acquire+0x1d5/0x580 [ 57.096781] __mutex_lock+0x16f/0x19d0 [ 57.101150] mutex_lock_nested+0x16/0x20 [ 57.105692] __cpuhp_setup_state_cpuslocked+0x5b/0x5f0 [ 57.111451] __cpuhp_setup_state+0xb0/0x140 [ 57.116258] kvm_guest_init+0x1f3/0x20f [ 57.120719] setup_arch+0x1879/0x1a93 [ 57.125035] start_kernel+0xa5/0x754 [ 57.129232] x86_64_start_reservations+0x2a/0x2c [ 57.134470] x86_64_start_kernel+0x77/0x7a [ 57.139187] verify_cpu+0x0/0xfb [ 57.143034] [ 57.143034] -> #2 (cpu_hotplug_lock.rw_sem){++++}: [ 57.149406] __lock_acquire+0x328f/0x4620 [ 57.154038] lock_acquire+0x1d5/0x580 [ 57.158321] cpus_read_lock+0x42/0x90 [ 57.162602] static_key_slow_inc+0x9d/0x3c0 [ 57.167407] tracepoint_probe_register_prio+0x80d/0x9a0 [ 57.173251] tracepoint_probe_register+0x2a/0x40 [ 57.178490] trace_event_reg+0x167/0x320 [ 57.183033] perf_trace_init+0x4ef/0xab0 [ 57.187576] perf_tp_event_init+0x7d/0xf0 [ 57.192207] perf_try_init_event+0xc9/0x1f0 [ 57.197010] perf_event_alloc+0x1c5b/0x2a00 [ 57.201814] SYSC_perf_event_open+0x84e/0x2e00 [ 57.206881] SyS_perf_event_open+0x39/0x50 [ 57.211600] do_fast_syscall_32+0x3f2/0xf05 [ 57.216406] entry_SYSENTER_compat+0x51/0x60 [ 57.221292] [ 57.221292] -> #1 (tracepoints_mutex){+.+.}: [ 57.227143] __lock_acquire+0x328f/0x4620 [ 57.231783] lock_acquire+0x1d5/0x580 [ 57.236068] __mutex_lock+0x16f/0x19d0 [ 57.240438] mutex_lock_nested+0x16/0x20 [ 57.244981] tracepoint_probe_register_prio+0xa0/0x9a0 [ 57.250739] tracepoint_probe_register+0x2a/0x40 [ 57.255979] trace_event_reg+0x167/0x320 [ 57.260526] perf_trace_init+0x4ef/0xab0 [ 57.265071] perf_tp_event_init+0x7d/0xf0 [ 57.269704] perf_try_init_event+0xc9/0x1f0 [ 57.274506] perf_event_alloc+0x1c5b/0x2a00 [ 57.279319] SYSC_perf_event_open+0x84e/0x2e00 [ 57.284383] SyS_perf_event_open+0x39/0x50 [ 57.289100] do_fast_syscall_32+0x3f2/0xf05 [ 57.293907] entry_SYSENTER_compat+0x51/0x60 [ 57.298796] [ 57.298796] -> #0 (event_mutex){+.+.}: [ 57.304128] check_prev_add+0x865/0x1520 [ 57.308672] __lock_acquire+0x328f/0x4620 [ 57.313302] lock_acquire+0x1d5/0x580 [ 57.317671] __mutex_lock+0x16f/0x19d0 [ 57.322042] mutex_lock_nested+0x16/0x20 [ 57.326586] perf_trace_destroy+0x28/0x100 [ 57.331316] tp_perf_event_destroy+0x15/0x20 [ 57.336208] _free_event+0x41d/0x1170 [ 57.340491] put_event+0x24/0x30 [ 57.344340] perf_mmap_close+0x60d/0xf90 [ 57.348886] remove_vma+0xb4/0x1b0 [ 57.352910] do_munmap+0x82a/0xdf0 [ 57.356934] mmap_region+0x59e/0x15a0 [ 57.361218] do_mmap+0x6a1/0xd50 [ 57.365070] vm_mmap_pgoff+0x1de/0x280 [ 57.369442] SyS_mmap_pgoff+0x23b/0x5f0 [ 57.373909] do_fast_syscall_32+0x3f2/0xf05 [ 57.378714] entry_SYSENTER_compat+0x51/0x60 [ 57.383606] [ 57.383606] other info that might help us debug this: [ 57.383606] [ 57.391709] Chain exists of: [ 57.391709] event_mutex --> &sb->s_type->i_mutex_key#5 --> &mm->mmap_sem [ 57.391709] [ 57.403035] Possible unsafe locking scenario: [ 57.403035] [ 57.409070] CPU0 CPU1 [ 57.413700] ---- ---- [ 57.418329] lock(&mm->mmap_sem); [ 57.421834] lock(&sb->s_type->i_mutex_key#5); [ 57.428983] lock(&mm->mmap_sem); [ 57.435003] lock(event_mutex); [ 57.438339] [ 57.438339] *** DEADLOCK *** [ 57.438339] [ 57.444361] 1 lock held by syz-executor0/3173: [ 57.448901] #0: (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 57.457368] [ 57.457368] stack backtrace: [ 57.461829] CPU: 1 PID: 3173 Comm: syz-executor0 Not tainted 4.14.0-rc2+ #16 [ 57.468977] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 57.478294] Call Trace: [ 57.480854] dump_stack+0x194/0x257 [ 57.484445] ? arch_local_irq_restore+0x53/0x53 [ 57.489080] print_circular_bug+0x503/0x710 [ 57.493366] ? print_circular_bug_entry+0xb0/0xb0 [ 57.498172] ? __unwind_start+0x169/0x330 [ 57.502283] ? __kernel_text_address+0xd/0x40 [ 57.506750] ? unwind_get_return_address+0x61/0xa0 [ 57.511651] check_prev_add+0x865/0x1520 [ 57.515676] ? copy_trace+0x1d0/0x1d0 [ 57.519441] ? check_usage+0xb70/0xb70 [ 57.523294] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 57.529144] ? hlock_class+0x140/0x140 [ 57.532995] ? copy_trace+0x1d0/0x1d0 [ 57.536758] __lock_acquire+0x328f/0x4620 [ 57.540870] ? __lock_acquire+0x328f/0x4620 [ 57.545155] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 57.550138] ? copy_trace+0x1d0/0x1d0 [ 57.553903] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 57.559057] ? __unwind_start+0x169/0x330 [ 57.563170] ? __kernel_text_address+0xd/0x40 [ 57.567627] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 57.572604] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 57.577581] ? unwind_dump+0x4c0/0x4c0 [ 57.581440] ? unwind_dump+0x4c0/0x4c0 [ 57.585296] ? mmap_region+0x59e/0x15a0 [ 57.589334] ? __unwind_start+0x169/0x330 [ 57.593445] ? __kernel_text_address+0xd/0x40 [ 57.597912] ? unwind_get_return_address+0x61/0xa0 [ 57.602807] ? __save_stack_trace+0x61/0xd0 [ 57.607092] ? remove_vma+0xb4/0x1b0 [ 57.610769] ? save_stack_trace+0x16/0x20 [ 57.614888] ? __lock_acquire+0x20fd/0x4620 [ 57.619172] ? __unwind_start+0x169/0x330 [ 57.623283] ? __kernel_text_address+0xd/0x40 [ 57.627741] ? unwind_get_return_address+0x61/0xa0 [ 57.632633] ? check_noncircular+0x20/0x20 [ 57.636835] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 57.641993] ? mmap_region+0x59e/0x15a0 [ 57.645940] ? __lock_acquire+0x20fd/0x4620 [ 57.650224] ? mark_held_locks+0xb2/0x100 [ 57.654344] lock_acquire+0x1d5/0x580 [ 57.658110] ? perf_trace_destroy+0x28/0x100 [ 57.662483] ? finish_task_switch+0x1d3/0x740 [ 57.666943] ? lock_release+0xd70/0xd70 [ 57.670882] ? check_same_owner+0x320/0x320 [ 57.675165] ? preempt_notifier_dec+0x20/0x20 [ 57.679625] ? __might_sleep+0x95/0x190 [ 57.683563] ? perf_trace_destroy+0x28/0x100 [ 57.687938] __mutex_lock+0x16f/0x19d0 [ 57.691787] ? perf_trace_destroy+0x28/0x100 [ 57.696168] ? __sched_text_start+0x8/0x8 [ 57.700278] ? perf_trace_destroy+0x28/0x100 [ 57.704647] ? check_noncircular+0x20/0x20 [ 57.708849] ? mutex_lock_io_nested+0x1880/0x1880 [ 57.713653] ? lock_acquire+0x1d5/0x580 [ 57.717593] ? print_usage_bug+0x480/0x480 [ 57.721809] ? find_held_lock+0x39/0x1d0 [ 57.725835] ? check_noncircular+0x20/0x20 [ 57.730033] ? lock_downgrade+0x990/0x990 [ 57.734142] ? __mutex_lock+0x16f/0x19d0 [ 57.738166] ? __wake_up_common_lock+0x190/0x310 [ 57.742885] ? find_held_lock+0x39/0x1d0 [ 57.746909] ? check_noncircular+0x20/0x20 [ 57.751107] ? perf_addr_filters_splice+0x18f/0x810 [ 57.756088] ? lock_downgrade+0x990/0x990 [ 57.760199] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 57.765273] ? free_filters_list+0x2f0/0x2f0 [ 57.769644] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 57.774621] ? trace_hardirqs_on+0xd/0x10 [ 57.778743] ? __lock_is_held+0xbc/0x140 [ 57.782769] mutex_lock_nested+0x16/0x20 [ 57.786795] ? mutex_lock_nested+0x16/0x20 [ 57.790999] perf_trace_destroy+0x28/0x100 [ 57.795198] ? perf_tp_event_init+0xf0/0xf0 [ 57.799484] tp_perf_event_destroy+0x15/0x20 [ 57.803856] _free_event+0x41d/0x1170 [ 57.807618] ? ring_buffer_attach+0x830/0x830 [ 57.812075] ? wait_for_completion+0x7b0/0x7b0 [ 57.816621] ? ring_buffer_put+0x140/0x140