[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.48' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 36.476241] [ 36.477877] ====================================================== [ 36.484252] WARNING: possible circular locking dependency detected [ 36.490544] 4.14.302-syzkaller #0 Not tainted [ 36.495009] ------------------------------------------------------ [ 36.501387] syz-executor122/7981 is trying to acquire lock: [ 36.507154] (cpu_hotplug_lock.rw_sem){++++}, at: [] static_key_slow_inc+0xe/0x20 [ 36.516322] [ 36.516322] but task is already holding lock: [ 36.522267] (tracepoints_mutex){+.+.}, at: [] tracepoint_probe_register+0x68/0xc0 [ 36.531528] [ 36.531528] which lock already depends on the new lock. [ 36.531528] [ 36.539902] [ 36.539902] the existing dependency chain (in reverse order) is: [ 36.547493] [ 36.547493] -> #5 (tracepoints_mutex){+.+.}: [ 36.553362] __mutex_lock+0xc4/0x1310 [ 36.557658] tracepoint_probe_register+0x68/0xc0 [ 36.562910] trace_event_reg+0x272/0x330 [ 36.567679] perf_trace_init+0x424/0xa30 [ 36.572248] perf_tp_event_init+0x79/0xf0 [ 36.576892] perf_try_init_event+0xdf/0x1f0 [ 36.581710] perf_event_alloc.part.0+0xe2d/0x2640 [ 36.587066] SyS_perf_event_open+0x683/0x2530 [ 36.592063] do_syscall_64+0x1d5/0x640 [ 36.596450] entry_SYSCALL_64_after_hwframe+0x5e/0xd3 [ 36.602131] [ 36.602131] -> #4 (event_mutex){+.+.}: [ 36.607473] __mutex_lock+0xc4/0x1310 [ 36.611768] perf_trace_init+0x4f/0xa30 [ 36.616237] perf_tp_event_init+0x79/0xf0 [ 36.620883] perf_try_init_event+0xdf/0x1f0 [ 36.625701] perf_event_alloc.part.0+0xe2d/0x2640 [ 36.631040] SyS_perf_event_open+0x683/0x2530 [ 36.636032] do_syscall_64+0x1d5/0x640 [ 36.640503] entry_SYSCALL_64_after_hwframe+0x5e/0xd3 [ 36.646209] [ 36.646209] -> #3 (&cpuctx_mutex/1){+.+.}: [ 36.652110] __mutex_lock+0xc4/0x1310 [ 36.656420] SyS_perf_event_open+0xd13/0x2530 [ 36.661425] do_syscall_64+0x1d5/0x640 [ 36.665816] entry_SYSCALL_64_after_hwframe+0x5e/0xd3 [ 36.671531] [ 36.671531] -> #2 (&cpuctx_mutex){+.+.}: [ 36.677056] __mutex_lock+0xc4/0x1310 [ 36.681357] perf_event_init_cpu+0xb7/0x170 [ 36.687509] perf_event_init+0x2cc/0x308 [ 36.692198] start_kernel+0x45d/0x763 [ 36.696501] secondary_startup_64+0xa5/0xb0 [ 36.701315] [ 36.701315] -> #1 (pmus_lock){+.+.}: [ 36.706492] __mutex_lock+0xc4/0x1310 [ 36.710787] perf_event_init_cpu+0x2c/0x170 [ 36.715617] cpuhp_invoke_callback+0x1e6/0x1a80 [ 36.720913] _cpu_up+0x21e/0x520 [ 36.724777] do_cpu_up+0x9a/0x160 [ 36.728731] smp_init+0x197/0x1ac [ 36.732778] kernel_init_freeable+0x406/0x626 [ 36.737781] kernel_init+0xd/0x15d [ 36.741816] ret_from_fork+0x24/0x30 [ 36.746043] [ 36.746043] -> #0 (cpu_hotplug_lock.rw_sem){++++}: [ 36.752433] lock_acquire+0x170/0x3f0 [ 36.756728] cpus_read_lock+0x39/0xc0 [ 36.761022] static_key_slow_inc+0xe/0x20 [ 36.765665] tracepoint_add_func+0x747/0xa40 [ 36.770655] tracepoint_probe_register+0x8c/0xc0 [ 36.775954] trace_event_reg+0x272/0x330 [ 36.780681] perf_trace_init+0x424/0xa30 [ 36.785244] perf_tp_event_init+0x79/0xf0 [ 36.789883] perf_try_init_event+0xdf/0x1f0 [ 36.794725] perf_event_alloc.part.0+0xe2d/0x2640 [ 36.800064] SyS_perf_event_open+0x683/0x2530 [ 36.805055] do_syscall_64+0x1d5/0x640 [ 36.809524] entry_SYSCALL_64_after_hwframe+0x5e/0xd3 [ 36.815486] [ 36.815486] other info that might help us debug this: [ 36.815486] [ 36.823609] Chain exists of: [ 36.823609] cpu_hotplug_lock.rw_sem --> event_mutex --> tracepoints_mutex [ 36.823609] [ 36.835035] Possible unsafe locking scenario: [ 36.835035] [ 36.841063] CPU0 CPU1 [ 36.845699] ---- ---- [ 36.850336] lock(tracepoints_mutex); [ 36.854194] lock(event_mutex); [ 36.860059] lock(tracepoints_mutex); [ 36.866446] lock(cpu_hotplug_lock.rw_sem); [ 36.870831] [ 36.870831] *** DEADLOCK *** [ 36.870831] [ 36.876875] 4 locks held by syz-executor122/7981: [ 36.881690] #0: (&pmus_srcu){....}, at: [] perf_event_alloc.part.0+0xc44/0x2640 [ 36.890861] #1: (&cpuctx_mutex/1){+.+.}, at: [] perf_event_ctx_lock_nested+0x14d/0x2c0 [ 36.900631] #2: (event_mutex){+.+.}, at: [] perf_trace_init+0x4f/0xa30 [ 36.909113] #3: (tracepoints_mutex){+.+.}, at: [] tracepoint_probe_register+0x68/0xc0 [ 36.918801] [ 36.918801] stack backtrace: [ 36.923371] CPU: 1 PID: 7981 Comm: syz-executor122 Not tainted 4.14.302-syzkaller #0 [ 36.931322] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 [ 36.940738] Call Trace: [ 36.943303] dump_stack+0x1b2/0x281 [ 36.946995] print_circular_bug.constprop.0.cold+0x2d7/0x41e [ 36.953389] __lock_acquire+0x2e0e/0x3f20 [ 36.958384] ? trace_hardirqs_on+0x10/0x10 [ 36.962769] ? tracepoint_probe_register+0x68/0xc0 [ 36.967675] lock_acquire+0x170/0x3f0 [ 36.971470] ? static_key_slow_inc+0xe/0x20 [ 36.975764] ? dummy_handler+0x10/0x10 [ 36.979622] cpus_read_lock+0x39/0xc0 [ 36.983404] ? static_key_slow_inc+0xe/0x20 [ 36.987709] static_key_slow_inc+0xe/0x20 [ 36.992005] tracepoint_add_func+0x747/0xa40 [ 36.996388] ? dummy_handler+0x10/0x10 [ 37.000348] tracepoint_probe_register+0x8c/0xc0 [ 37.005087] ? for_each_kernel_tracepoint+0x80/0x80 [ 37.010093] ? pcpu_alloc+0x8f/0xf50 [ 37.013868] ? dummy_handler+0x10/0x10 [ 37.017729] trace_event_reg+0x272/0x330 [ 37.021779] perf_trace_init+0x424/0xa30 [ 37.025900] perf_tp_event_init+0x79/0xf0 [ 37.030041] perf_try_init_event+0xdf/0x1f0 [ 37.034343] perf_event_alloc.part.0+0xe2d/0x2640 [ 37.039201] SyS_perf_event_open+0x683/0x2530 [ 37.043676] ? perf_bp_event+0x180/0x180 [ 37.047715] ? lock_downgrade+0x740/0x740 [ 37.051838] ? do_syscall_64+0x4c/0x640 [ 37.055784] ? perf_bp_event+0x180/0x180 [ 37.059816] do_syscall_64+0x1d5/0x640 [ 37.063683] entry_SYSCALL_64_after_hwframe+0x5e/0xd3 [ 37.068954] RIP: 0033:0x7f8c5a4b1489 [ 37.072651] RSP: 002b:00007ffc2a1b1e08 EFLAGS: 00000246 ORIG_RAX: 00000