Warning: Permanently added '10.128.0.39' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 41.928024][ C0] [ 41.930363][ C0] ======================================================== [ 41.937806][ C0] WARNING: possible irq lock inversion dependency detected [ 41.944977][ C0] 5.6.0-syzkaller #0 Not tainted [ 41.949898][ C0] -------------------------------------------------------- [ 41.957150][ C0] ksoftirqd/0/9 just changed the state of lock: [ 41.963361][ C0] ffff8880a9759cd8 (&ctx->ctx_lock){..-.}-{2:2}, at: free_ioctx_users+0x30/0x1c0 [ 41.972452][ C0] but this lock took another, SOFTIRQ-unsafe lock in the past: [ 41.979977][ C0] (&pid->wait_pidfd){+.+.}-{2:2} [ 41.979983][ C0] [ 41.979983][ C0] [ 41.979983][ C0] and interrupts could create inverse lock ordering between them. [ 41.979983][ C0] [ 41.999390][ C0] [ 41.999390][ C0] other info that might help us debug this: [ 42.007462][ C0] Possible interrupt unsafe locking scenario: [ 42.007462][ C0] [ 42.015843][ C0] CPU0 CPU1 [ 42.021184][ C0] ---- ---- [ 42.026532][ C0] lock(&pid->wait_pidfd); [ 42.031006][ C0] local_irq_disable(); [ 42.037737][ C0] lock(&ctx->ctx_lock); [ 42.044590][ C0] lock(&pid->wait_pidfd); [ 42.051590][ C0] [ 42.055028][ C0] lock(&ctx->ctx_lock); [ 42.059660][ C0] [ 42.059660][ C0] *** DEADLOCK *** [ 42.059660][ C0] [ 42.067788][ C0] 2 locks held by ksoftirqd/0/9: [ 42.072692][ C0] #0: ffffffff892e6be0 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0x0/0x30 [ 42.081863][ C0] #1: ffffffff892e6b90 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 [ 42.091137][ C0] [ 42.091137][ C0] the shortest dependencies between 2nd lock and 1st lock: [ 42.100490][ C0] -> (&pid->wait_pidfd){+.+.}-{2:2} { [ 42.105938][ C0] HARDIRQ-ON-W at: [ 42.109981][ C0] lock_acquire+0x169/0x480 [ 42.116294][ C0] _raw_spin_lock+0x2a/0x40 [ 42.122603][ C0] proc_pid_make_inode+0x187/0x2d0 [ 42.129511][ C0] proc_pid_instantiate+0x4b/0x1a0 [ 42.136417][ C0] proc_pid_lookup+0x218/0x2f0 [ 42.143064][ C0] proc_root_lookup+0x1b/0x50 [ 42.149535][ C0] __lookup_slow+0x240/0x370 [ 42.155918][ C0] walk_component+0x442/0x680 [ 42.162554][ C0] link_path_walk+0x66d/0xba0 [ 42.169071][ C0] path_openat+0x21d/0x38b0 [ 42.175395][ C0] do_filp_open+0x191/0x3a0 [ 42.181711][ C0] do_sys_openat2+0x463/0x770 [ 42.188184][ C0] __x64_sys_open+0x1af/0x1e0 [ 42.194660][ C0] do_syscall_64+0xf3/0x1b0 [ 42.200974][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 42.208667][ C0] SOFTIRQ-ON-W at: [ 42.212706][ C0] lock_acquire+0x169/0x480 [ 42.219015][ C0] _raw_spin_lock+0x2a/0x40 [ 42.225313][ C0] proc_pid_make_inode+0x187/0x2d0 [ 42.232302][ C0] proc_pid_instantiate+0x4b/0x1a0 [ 42.239236][ C0] proc_pid_lookup+0x218/0x2f0 [ 42.245930][ C0] proc_root_lookup+0x1b/0x50 [ 42.252596][ C0] __lookup_slow+0x240/0x370 [ 42.258989][ C0] walk_component+0x442/0x680 [ 42.265460][ C0] link_path_walk+0x66d/0xba0 [ 42.271930][ C0] path_openat+0x21d/0x38b0 [ 42.278240][ C0] do_filp_open+0x191/0x3a0 [ 42.284623][ C0] do_sys_openat2+0x463/0x770 [ 42.291091][ C0] __x64_sys_open+0x1af/0x1e0 [ 42.297563][ C0] do_syscall_64+0xf3/0x1b0 [ 42.303872][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 42.311555][ C0] INITIAL USE at: [ 42.315521][ C0] lock_acquire+0x169/0x480 [ 42.321743][ C0] _raw_spin_lock_irqsave+0x9e/0xc0 [ 42.328652][ C0] __wake_up+0xb8/0x150 [ 42.335472][ C0] do_notify_parent+0x167/0xce0 [ 42.342045][ C0] do_exit+0x12c5/0x1f80 [ 42.348097][ C0] call_usermodehelper_exec_async+0x47c/0x480 [ 42.355886][ C0] ret_from_fork+0x24/0x30 [ 42.362436][ C0] } [ 42.365008][ C0] ... key at: [] alloc_pid.__key+0x0/0x10 [ 42.372887][ C0] ... acquired at: [ 42.376755][ C0] lock_acquire+0x169/0x480 [ 42.381416][ C0] _raw_spin_lock+0x2a/0x40 [ 42.387086][ C0] io_submit_one+0x10f5/0x1a80 [ 42.392008][ C0] __se_sys_io_submit+0x117/0x220 [ 42.397181][ C0] do_syscall_64+0xf3/0x1b0 [ 42.401833][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 42.407873][ C0] [ 42.410173][ C0] -> (&ctx->ctx_lock){..-.}-{2:2} { [ 42.415338][ C0] IN-SOFTIRQ-W at: [ 42.419292][ C0] lock_acquire+0x169/0x480 [ 42.425414][ C0] _raw_spin_lock_irq+0x67/0x80 [ 42.432230][ C0] free_ioctx_users+0x30/0x1c0 [ 42.441568][ C0] percpu_ref_put+0x18d/0x1a0 [ 42.447863][ C0] rcu_core+0x816/0x1120 [ 42.453733][ C0] __do_softirq+0x268/0x80c [ 42.459865][ C0] run_ksoftirqd+0x60/0xf0 [ 42.465913][ C0] smpboot_thread_fn+0x572/0x970 [ 42.472619][ C0] kthread+0x353/0x380 [ 42.478444][ C0] ret_from_fork+0x24/0x30 [ 42.484604][ C0] INITIAL USE at: [ 42.488491][ C0] lock_acquire+0x169/0x480 [ 42.494527][ C0] _raw_spin_lock_irq+0x67/0x80 [ 42.500975][ C0] io_submit_one+0x10cb/0x1a80 [ 42.507283][ C0] __se_sys_io_submit+0x117/0x220 [ 42.513931][ C0] do_syscall_64+0xf3/0x1b0 [ 42.519974][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 42.527400][ C0] } [ 42.529878][ C0] ... key at: [] ioctx_alloc.__key+0x0/0x10 [ 42.537826][ C0] ... acquired at: [ 42.541620][ C0] mark_lock+0x529/0x1b00 [ 42.546104][ C0] __lock_acquire+0xaa7/0x2b90 [ 42.551184][ C0] lock_acquire+0x169/0x480 [ 42.555829][ C0] _raw_spin_lock_irq+0x67/0x80 [ 42.560823][ C0] free_ioctx_users+0x30/0x1c0 [ 42.565729][ C0] percpu_ref_put+0x18d/0x1a0 [ 42.570554][ C0] rcu_core+0x816/0x1120 [ 42.575130][ C0] __do_softirq+0x268/0x80c [ 42.579886][ C0] run_ksoftirqd+0x60/0xf0 [ 42.584472][ C0] smpboot_thread_fn+0x572/0x970 [ 42.589559][ C0] kthread+0x353/0x380 [ 42.593776][ C0] ret_from_fork+0x24/0x30 [ 42.598338][ C0] [ 42.600649][ C0] [ 42.600649][ C0] stack backtrace: [ 42.606524][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.6.0-syzkaller #0 [ 42.614214][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.624255][ C0] Call Trace: [ 42.627524][ C0] dump_stack+0x1e9/0x30e [ 42.631844][ C0] print_irq_inversion_bug+0xb67/0xe90 [ 42.637369][ C0] ? arch_stack_walk+0xb4/0xe0 [ 42.642108][ C0] ? ret_from_fork+0x24/0x30 [ 42.646672][ C0] check_usage_forwards+0x13f/0x240 [ 42.652364][ C0] ? save_trace+0x49/0xb60 [ 42.656760][ C0] mark_lock+0x529/0x1b00 [ 42.661063][ C0] ? check_usage_backwards+0x240/0x240 [ 42.666502][ C0] ? mark_lock+0x102/0x1b00 [ 42.670990][ C0] ? __lock_acquire+0x116c/0x2b90 [ 42.675983][ C0] __lock_acquire+0xaa7/0x2b90 [ 42.680724][ C0] ? pcpu_block_update+0x564/0x890 [ 42.685814][ C0] lock_acquire+0x169/0x480 [ 42.690303][ C0] ? free_ioctx_users+0x30/0x1c0 [ 42.695231][ C0] ? rcu_lock_acquire+0x5/0x30 [ 42.700002][ C0] ? trace_irq_disable_rcuidle+0x1f/0x1d0 [ 42.705696][ C0] ? percpu_ref_noop_confirm_switch+0x10/0x10 [ 42.711783][ C0] _raw_spin_lock_irq+0x67/0x80 [ 42.716607][ C0] ? free_ioctx_users+0x30/0x1c0 [ 42.721523][ C0] free_ioctx_users+0x30/0x1c0 [ 42.726280][ C0] ? percpu_ref_noop_confirm_switch+0x10/0x10 [ 42.732315][ C0] ? percpu_ref_noop_confirm_switch+0x10/0x10 [ 42.738356][ C0] percpu_ref_put+0x18d/0x1a0 [ 42.743015][ C0] rcu_core+0x816/0x1120 [ 42.747240][ C0] __do_softirq+0x268/0x80c [ 42.751715][ C0] ? run_ksoftirqd+0x60/0xf0 [ 42.756275][ C0] run_ksoftirqd+0x60/0xf0 [ 42.760765][ C0] ? ksoftirqd_should_run+0x20/0x20 [ 42.766091][ C0] smpboot_thread_fn+0x572/0x970 [ 42.771060][ C0] kthread+0x353/0x380 [ 42.775113][ C0] ? cpu_report_death+0x110/0x110 [ 42.780113][