Warning: Permanently added '10.128.10.46' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 61.579670][ C0] [ 61.582030][ C0] ======================================================== [ 61.589202][ C0] WARNING: possible irq lock inversion dependency detected [ 61.596399][ C0] 5.6.0-syzkaller #0 Not tainted [ 61.601402][ C0] -------------------------------------------------------- [ 61.608599][ C0] swapper/0/0 just changed the state of lock: [ 61.614651][ C0] ffff888088c7fcd8 (&ctx->ctx_lock){..-.}-{2:2}, at: free_ioctx_users+0x2b/0x450 [ 61.624974][ C0] but this lock took another, SOFTIRQ-unsafe lock in the past: [ 61.632565][ C0] (&pid->wait_pidfd){+.+.}-{2:2} [ 61.632576][ C0] [ 61.632576][ C0] [ 61.632576][ C0] and interrupts could create inverse lock ordering between them. [ 61.632576][ C0] [ 61.651865][ C0] [ 61.651865][ C0] other info that might help us debug this: [ 61.660004][ C0] Possible interrupt unsafe locking scenario: [ 61.660004][ C0] [ 61.668299][ C0] CPU0 CPU1 [ 61.673655][ C0] ---- ---- [ 61.679008][ C0] lock(&pid->wait_pidfd); [ 61.683612][ C0] local_irq_disable(); [ 61.690349][ C0] lock(&ctx->ctx_lock); [ 61.697180][ C0] lock(&pid->wait_pidfd); [ 61.704545][ C0] [ 61.708084][ C0] lock(&ctx->ctx_lock); [ 61.712574][ C0] [ 61.712574][ C0] *** DEADLOCK *** [ 61.712574][ C0] [ 61.720710][ C0] 2 locks held by swapper/0/0: [ 61.725522][ C0] #0: ffffffff899baba0 (rcu_callback){....}-{0:0}, at: rcu_core+0x520/0x1370 [ 61.734373][ C0] #1: ffffffff899bacc0 (rcu_read_lock){....}-{1:2}, at: percpu_ref_switch_to_atomic_rcu+0x209/0x540 [ 61.745223][ C0] [ 61.745223][ C0] the shortest dependencies between 2nd lock and 1st lock: [ 61.754715][ C0] -> (&pid->wait_pidfd){+.+.}-{2:2} { [ 61.760166][ C0] HARDIRQ-ON-W at: [ 61.764229][ C0] lock_acquire+0x1f2/0x8f0 [ 61.770561][ C0] _raw_spin_lock+0x2a/0x40 [ 61.776889][ C0] proc_pid_make_inode+0x1f9/0x3c0 [ 61.783799][ C0] proc_pid_instantiate+0x51/0x150 [ 61.790712][ C0] proc_pid_lookup+0x1da/0x340 [ 61.797322][ C0] proc_root_lookup+0x20/0x60 [ 61.803804][ C0] __lookup_slow+0x256/0x490 [ 61.810363][ C0] walk_component+0x418/0x6a0 [ 61.816867][ C0] link_path_walk.part.0+0x4f1/0xb50 [ 61.824287][ C0] path_openat+0x25a/0x27b0 [ 61.830594][ C0] do_filp_open+0x203/0x260 [ 61.836914][ C0] do_sys_openat2+0x585/0x770 [ 61.843392][ C0] do_sys_open+0xc3/0x140 [ 61.849521][ C0] do_syscall_64+0xf6/0x7d0 [ 61.855839][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 61.863539][ C0] SOFTIRQ-ON-W at: [ 61.867587][ C0] lock_acquire+0x1f2/0x8f0 [ 61.873903][ C0] _raw_spin_lock+0x2a/0x40 [ 61.880337][ C0] proc_pid_make_inode+0x1f9/0x3c0 [ 61.887415][ C0] proc_pid_instantiate+0x51/0x150 [ 61.894348][ C0] proc_pid_lookup+0x1da/0x340 [ 61.901792][ C0] proc_root_lookup+0x20/0x60 [ 61.908290][ C0] __lookup_slow+0x256/0x490 [ 61.914698][ C0] walk_component+0x418/0x6a0 [ 61.921929][ C0] link_path_walk.part.0+0x4f1/0xb50 [ 61.929037][ C0] path_openat+0x25a/0x27b0 [ 61.935372][ C0] do_filp_open+0x203/0x260 [ 61.941682][ C0] do_sys_openat2+0x585/0x770 [ 61.948207][ C0] do_sys_open+0xc3/0x140 [ 61.954356][ C0] do_syscall_64+0xf6/0x7d0 [ 61.960751][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 61.968509][ C0] INITIAL USE at: [ 61.972559][ C0] lock_acquire+0x1f2/0x8f0 [ 61.978788][ C0] _raw_spin_lock_irqsave+0x8c/0xbf [ 61.985720][ C0] __wake_up_common_lock+0xb4/0x130 [ 61.992650][ C0] do_notify_parent+0x19e/0xe60 [ 61.999217][ C0] do_exit+0x238f/0x2dd0 [ 62.005276][ C0] call_usermodehelper_exec_async+0x507/0x710 [ 62.013060][ C0] ret_from_fork+0x24/0x30 [ 62.019182][ C0] } [ 62.021750][ C0] ... key at: [] __key.53714+0x0/0x40 [ 62.029264][ C0] ... acquired at: [ 62.033156][ C0] _raw_spin_lock+0x2a/0x40 [ 62.037828][ C0] io_submit_one+0xc1b/0x2ec0 [ 62.042657][ C0] __ia32_compat_sys_io_submit+0x1bf/0x530 [ 62.048613][ C0] do_fast_syscall_32+0x270/0xe90 [ 62.053790][ C0] entry_SYSENTER_compat+0x70/0x7f [ 62.059055][ C0] [ 62.061419][ C0] -> (&ctx->ctx_lock){..-.}-{2:2} { [ 62.066655][ C0] IN-SOFTIRQ-W at: [ 62.070624][ C0] lock_acquire+0x1f2/0x8f0 [ 62.076797][ C0] _raw_spin_lock_irq+0x5b/0x80 [ 62.083290][ C0] free_ioctx_users+0x2b/0x450 [ 62.089685][ C0] percpu_ref_switch_to_atomic_rcu+0x494/0x540 [ 62.097606][ C0] rcu_core+0x59f/0x1370 [ 62.103478][ C0] __do_softirq+0x26c/0x9f7 [ 62.109728][ C0] irq_exit+0x192/0x1d0 [ 62.115517][ C0] smp_apic_timer_interrupt+0x19e/0x600 [ 62.122831][ C0] apic_timer_interrupt+0xf/0x20 [ 62.129408][ C0] native_safe_halt+0xe/0x10 [ 62.135628][ C0] default_idle+0x49/0x350 [ 62.141683][ C0] do_idle+0x393/0x690 [ 62.147379][ C0] cpu_startup_entry+0x14/0x20 [ 62.153771][ C0] start_kernel+0x867/0x8a1 [ 62.159901][ C0] secondary_startup_64+0xa4/0xb0 [ 62.166547][ C0] INITIAL USE at: [ 62.170467][ C0] lock_acquire+0x1f2/0x8f0 [ 62.176656][ C0] _raw_spin_lock_irq+0x5b/0x80 [ 62.183055][ C0] io_submit_one+0xbd6/0x2ec0 [ 62.189415][ C0] __ia32_compat_sys_io_submit+0x1bf/0x530 [ 62.196782][ C0] do_fast_syscall_32+0x270/0xe90 [ 62.203404][ C0] entry_SYSENTER_compat+0x70/0x7f [ 62.210064][ C0] } [ 62.212572][ C0] ... key at: [] __key.55192+0x0/0x40 [ 62.219997][ C0] ... acquired at: [ 62.223780][ C0] mark_lock+0x624/0xf10 [ 62.228190][ C0] __lock_acquire+0x1d28/0x4e00 [ 62.233191][ C0] lock_acquire+0x1f2/0x8f0 [ 62.237842][ C0] _raw_spin_lock_irq+0x5b/0x80 [ 62.245202][ C0] free_ioctx_users+0x2b/0x450 [ 62.250123][ C0] percpu_ref_switch_to_atomic_rcu+0x494/0x540 [ 62.256438][ C0] rcu_core+0x59f/0x1370 [ 62.260845][ C0] __do_softirq+0x26c/0x9f7 [ 62.265502][ C0] irq_exit+0x192/0x1d0 [ 62.269812][ C0] smp_apic_timer_interrupt+0x19e/0x600 [ 62.275512][ C0] apic_timer_interrupt+0xf/0x20 [ 62.280598][ C0] native_safe_halt+0xe/0x10 [ 62.285359][ C0] default_idle+0x49/0x350 [ 62.290060][ C0] do_idle+0x393/0x690 [ 62.294284][ C0] cpu_startup_entry+0x14/0x20 [ 62.299218][ C0] start_kernel+0x867/0x8a1 [ 62.303974][ C0] secondary_startup_64+0xa4/0xb0 [ 62.309141][ C0] [ 62.311443][ C0] [ 62.311443][ C0] stack backtrace: [ 62.317318][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.0-syzkaller #0 [ 62.324851][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.335240][ C0] Call Trace: [ 62.338512][ C0] [ 62.341959][ C0] dump_stack+0x188/0x20d [ 62.346312][ C0] check_usage_forwards.cold+0x20/0x29 [ 62.351845][ C0] ? check_usage_backwards+0x4e0/0x4e0 [ 62.357291][ C0] ? stack_trace_consume_entry+0x160/0x160 [ 62.363198][ C0] ? __read_once_size_nocheck.constprop.0+0x10/0x10 [ 62.369828][ C0] ? save_trace+0x42/0x9f0 [ 62.374226][ C0] mark_lock+0x624/0xf10 [ 62.378449][ C0] ? check_usage_backwards+0x4e0/0x4e0 [ 62.383882][ C0] ? print_usage_bug+0x240/0x240 [ 62.389015][ C0] ? print_usage_bug+0x240/0x240 [ 62.393937][ C0] ? mark_lock+0x12b/0xf10 [ 62.398520][ C0] __lock_acquire+0x1d28/0x4e00 [ 62.403533][ C0] ? mark_held_locks+0xe0/0xe0 [ 62.408722][ C0] ? __wake_up_common_lock+0xde/0x130 [ 62.414331][ C0] lock_acquire+0x1f2/0x8f0 [ 62.419035][ C0] ? free_ioctx_users+0x2b/0x450 [ 62.424178][ C0] ? lock_release+0x800/0x800 [ 62.429086][ C0] ? lock_acquire+0x1f2/0x8f0 [ 62.433758][ C0] ? percpu_ref_switch_to_atomic_rcu+0x209/0x540 [ 62.440528][ C0] ? lock_release+0x800/0x800 [ 62.445301][ C0] ? _raw_spin_unlock_irqrestore+0x62/0xe0 [ 62.451084][ C0] _raw_spin_lock_irq+0x5b/0x80 [ 62.455920][ C0] ? free_ioctx_users+0x2b/0x450 [ 62.460833][ C0] free_ioctx_users+0x2b/0x450 [ 62.466108][ C0] percpu_ref_switch_to_atomic_rcu+0x494/0x540 [ 62.472254][ C0] rcu_core+0x59f/0x1370 [ 62.476476][ C0] ? __rcu_read_unlock+0x700/0x700 [ 62.481560][ C0] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 62.487166][ C0] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.493274][ C0] ? run_rebalance_domains+0x202/0x2c0 [ 62.498717][ C0] __do_softirq+0x26c/0x9f7 [ 62.503332][ C0] irq_exit+0x192/0x1d0 [ 62.507475][ C0] smp_apic_timer_interrupt+0x19e/0x600 [ 62.513085][ C0] apic_timer_interrupt+0xf/0x20 [ 62.517995][ C0] [ 62.521012][ C0] RIP: 0010:native_safe_halt+0xe/0x10 [ 62.527003][ C0] Code: cc cc cc cc cc cc cc cc cc cc cc cc e9 07 00 00 00 0f 00 2d 44 ae 5e 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 34 ae 5e 00 fb f4 cc 41 56 41 55 41 54 55 53 e8 c3 07 97 f9 e8 9e 72 cb fb 0f 1f [ 62.546690][ C0] RSP: 0018:ffffffff89807d98 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 [ 62.555228][ C0] RAX: 1ffffffff13291af RBX: ffffffff898864c0 RCX: 0000000000000000 [ 62.563433][ C0] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffffffff89886d84 [ 62.571455][ C0] RBP: dffffc0000000000 R08: ffffffff898864c0 R09: 0000000000000000 [ 62.579542][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: fffffbfff1310c98 [ 62.587502][ C0] R13: 0000000000000000 R14: ffffffff8a883540 R15: 0000000000000000 [ 62.595469][ C0] default_idle+0x49/0x350 [ 62.599891][ C0] do_idle+0x393/0x690 [ 62.603962][ C0] ? rcu_read_lock_held+0x9c/0xb0 [ 62.609097][ C0] ? arch_cpu_idle_exit+0x70/0x70 [ 62.614119][ C0] ? schedule+0xe7/0x2a0 [ 62.618352][ C0] ? trace_init_perf_perm_irq_work_exit+0xe/0xe [ 62.625074][ C0] cpu_startup_entry+0x14/0x20 [ 62.629956][ C0] start_kernel+0x867/0x8a1