Warning: Permanently added '10.128.0.175' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 66.719210][ C1] [ 66.721567][ C1] ======================================================== [ 66.728730][ C1] WARNING: possible irq lock inversion dependency detected [ 66.735895][ C1] 5.3.0-rc6-next-20190830 #75 Not tainted [ 66.741581][ C1] -------------------------------------------------------- [ 66.748745][ C1] swapper/1/0 just changed the state of lock: [ 66.754777][ C1] ffff88808f86fb58 (&(&ctx->ctx_lock)->rlock){..-.}, at: free_ioctx_users+0x2d/0x490 [ 66.764217][ C1] but this lock took another, SOFTIRQ-unsafe lock in the past: [ 66.771731][ C1] (&fiq->waitq){+.+.} [ 66.771737][ C1] [ 66.771737][ C1] [ 66.771737][ C1] and interrupts could create inverse lock ordering between them. [ 66.771737][ C1] [ 66.790150][ C1] [ 66.790150][ C1] other info that might help us debug this: [ 66.798188][ C1] Possible interrupt unsafe locking scenario: [ 66.798188][ C1] [ 66.806478][ C1] CPU0 CPU1 [ 66.811817][ C1] ---- ---- [ 66.817155][ C1] lock(&fiq->waitq); [ 66.821195][ C1] local_irq_disable(); [ 66.827925][ C1] lock(&(&ctx->ctx_lock)->rlock); [ 66.835612][ C1] lock(&fiq->waitq); [ 66.842168][ C1] [ 66.845595][ C1] lock(&(&ctx->ctx_lock)->rlock); [ 66.850933][ C1] [ 66.850933][ C1] *** DEADLOCK *** [ 66.850933][ C1] [ 66.859054][ C1] 2 locks held by swapper/1/0: [ 66.863809][ C1] #0: ffffffff88fa7e40 (rcu_callback){....}, at: rcu_core+0x60e/0x1560 [ 66.872145][ C1] #1: ffffffff88fa7e80 (rcu_read_lock_sched){....}, at: percpu_ref_switch_to_atomic_rcu+0x20e/0x570 [ 66.882973][ C1] [ 66.882973][ C1] the shortest dependencies between 2nd lock and 1st lock: [ 66.892330][ C1] -> (&fiq->waitq){+.+.} { [ 66.896812][ C1] HARDIRQ-ON-W at: [ 66.900874][ C1] lock_acquire+0x190/0x410 [ 66.907173][ C1] _raw_spin_lock+0x2f/0x40 [ 66.913473][ C1] flush_bg_queue+0x1f1/0x3b0 [ 66.919945][ C1] fuse_request_queue_background+0x2f8/0x5b0 [ 66.927735][ C1] fuse_request_send_background+0x58/0x110 [ 66.935343][ C1] cuse_channel_open+0x5c3/0x839 [ 66.942078][ C1] misc_open+0x395/0x4c0 [ 66.948122][ C1] chrdev_open+0x245/0x6b0 [ 66.954337][ C1] do_dentry_open+0x4df/0x1250 [ 66.960898][ C1] vfs_open+0xa0/0xd0 [ 66.966697][ C1] path_openat+0x10e9/0x46d0 [ 66.973195][ C1] do_filp_open+0x1a1/0x280 [ 66.979511][ C1] do_sys_open+0x3fe/0x5d0 [ 66.985724][ C1] __x64_sys_openat+0x9d/0x100 [ 66.992303][ C1] do_syscall_64+0xfa/0x760 [ 66.998608][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 67.006289][ C1] SOFTIRQ-ON-W at: [ 67.010338][ C1] lock_acquire+0x190/0x410 [ 67.016634][ C1] _raw_spin_lock+0x2f/0x40 [ 67.022945][ C1] flush_bg_queue+0x1f1/0x3b0 [ 67.029417][ C1] fuse_request_queue_background+0x2f8/0x5b0 [ 67.037207][ C1] fuse_request_send_background+0x58/0x110 [ 67.044812][ C1] cuse_channel_open+0x5c3/0x839 [ 67.051562][ C1] misc_open+0x395/0x4c0 [ 67.057608][ C1] chrdev_open+0x245/0x6b0 [ 67.063907][ C1] do_dentry_open+0x4df/0x1250 [ 67.070480][ C1] vfs_open+0xa0/0xd0 [ 67.076259][ C1] path_openat+0x10e9/0x46d0 [ 67.082646][ C1] do_filp_open+0x1a1/0x280 [ 67.088947][ C1] do_sys_open+0x3fe/0x5d0 [ 67.095159][ C1] __x64_sys_openat+0x9d/0x100 [ 67.101731][ C1] do_syscall_64+0xfa/0x760 [ 67.108042][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 67.115726][ C1] INITIAL USE at: [ 67.119709][ C1] lock_acquire+0x190/0x410 [ 67.125922][ C1] _raw_spin_lock+0x2f/0x40 [ 67.132240][ C1] flush_bg_queue+0x1f1/0x3b0 [ 67.138625][ C1] fuse_request_queue_background+0x2f8/0x5b0 [ 67.146318][ C1] fuse_request_send_background+0x58/0x110 [ 67.153831][ C1] cuse_channel_open+0x5c3/0x839 [ 67.160476][ C1] misc_open+0x395/0x4c0 [ 67.166532][ C1] chrdev_open+0x245/0x6b0 [ 67.172661][ C1] do_dentry_open+0x4df/0x1250 [ 67.179155][ C1] vfs_open+0xa0/0xd0 [ 67.184846][ C1] path_openat+0x10e9/0x46d0 [ 67.191164][ C1] do_filp_open+0x1a1/0x280 [ 67.197392][ C1] do_sys_open+0x3fe/0x5d0 [ 67.203514][ C1] __x64_sys_openat+0x9d/0x100 [ 67.209989][ C1] do_syscall_64+0xfa/0x760 [ 67.216202][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 67.223798][ C1] } [ 67.226378][ C1] ... key at: [] __key.44810+0x0/0x40 [ 67.233887][ C1] ... acquired at: [ 67.237757][ C1] _raw_spin_lock+0x2f/0x40 [ 67.242435][ C1] io_submit_one+0xefa/0x2ef0 [ 67.247256][ C1] __x64_sys_io_submit+0x1bd/0x570 [ 67.252533][ C1] do_syscall_64+0xfa/0x760 [ 67.257189][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 67.263220][ C1] [ 67.265532][ C1] -> (&(&ctx->ctx_lock)->rlock){..-.} { [ 67.271052][ C1] IN-SOFTIRQ-W at: [ 67.275012][ C1] lock_acquire+0x190/0x410 [ 67.281138][ C1] _raw_spin_lock_irq+0x60/0x80 [ 67.287625][ C1] free_ioctx_users+0x2d/0x490 [ 67.294029][ C1] percpu_ref_switch_to_atomic_rcu+0x4c0/0x570 [ 67.301807][ C1] rcu_core+0x581/0x1560 [ 67.307687][ C1] rcu_core_si+0x9/0x10 [ 67.313466][ C1] __do_softirq+0x262/0x98c [ 67.319608][ C1] irq_exit+0x19b/0x1e0 [ 67.325386][ C1] smp_apic_timer_interrupt+0x1a3/0x610 [ 67.332570][ C1] apic_timer_interrupt+0xf/0x20 [ 67.339135][ C1] native_safe_halt+0xe/0x10 [ 67.345357][ C1] default_enter_idle+0x71/0xf0 [ 67.351829][ C1] cpuidle_enter_state+0xef/0xfb0 [ 67.358491][ C1] cpuidle_enter+0x4f/0xa0 [ 67.364530][ C1] do_idle+0x45f/0x6e0 [ 67.370222][ C1] cpu_startup_entry+0x1b/0x20 [ 67.376610][ C1] start_secondary+0x2f4/0x410 [ 67.382996][ C1] secondary_startup_64+0xa4/0xb0 [ 67.389642][ C1] INITIAL USE at: [ 67.393530][ C1] lock_acquire+0x190/0x410 [ 67.399573][ C1] _raw_spin_lock_irq+0x60/0x80 [ 67.405975][ C1] io_submit_one+0xeb5/0x2ef0 [ 67.412208][ C1] __x64_sys_io_submit+0x1bd/0x570 [ 67.418860][ C1] do_syscall_64+0xfa/0x760 [ 67.424906][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 67.432348][ C1] } [ 67.434835][ C1] ... key at: [] __key.54358+0x0/0x40 [ 67.442275][ C1] ... acquired at: [ 67.446068][ C1] mark_lock+0x517/0x1220 [ 67.450544][ C1] __lock_acquire+0x1e8e/0x4a00 [ 67.455543][ C1] lock_acquire+0x190/0x410 [ 67.460208][ C1] _raw_spin_lock_irq+0x60/0x80 [ 67.465225][ C1] free_ioctx_users+0x2d/0x490 [ 67.470144][ C1] percpu_ref_switch_to_atomic_rcu+0x4c0/0x570 [ 67.476459][ C1] rcu_core+0x581/0x1560 [ 67.480849][ C1] rcu_core_si+0x9/0x10 [ 67.485169][ C1] __do_softirq+0x262/0x98c [ 67.489817][ C1] irq_exit+0x19b/0x1e0 [ 67.494116][ C1] smp_apic_timer_interrupt+0x1a3/0x610 [ 67.499805][ C1] apic_timer_interrupt+0xf/0x20 [ 67.504890][ C1] native_safe_halt+0xe/0x10 [ 67.509642][ C1] default_enter_idle+0x71/0xf0 [ 67.514637][ C1] cpuidle_enter_state+0xef/0xfb0 [ 67.519803][ C1] cpuidle_enter+0x4f/0xa0 [ 67.524379][ C1] do_idle+0x45f/0x6e0 [ 67.528643][ C1] cpu_startup_entry+0x1b/0x20 [ 67.533561][ C1] start_secondary+0x2f4/0x410 [ 67.538472][ C1] secondary_startup_64+0xa4/0xb0 [ 67.543737][ C1] [ 67.546050][ C1] [ 67.546050][ C1] stack backtrace: [ 67.551919][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0-rc6-next-20190830 #75 [ 67.560224][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.570263][ C1] Call Trace: [ 67.573519][ C1] [ 67.576379][ C1] dump_stack+0x172/0x1f0 [ 67.580692][ C1] print_irq_inversion_bug.part.0+0x2e4/0x2f1 [ 67.586737][ C1] check_usage_forwards.cold+0x20/0x29 [ 67.592184][ C1] ? check_usage_backwards+0x330/0x330 [ 67.597617][ C1] ? save_trace+0x3e/0x8c0 [ 67.602007][ C1] mark_lock+0x517/0x1220 [ 67.606309][ C1] ? check_usage_backwards+0x330/0x330 [ 67.611742][ C1] __lock_acquire+0x1e8e/0x4a00 [ 67.616564][ C1] ? __kasan_check_read+0x11/0x20 [ 67.621562][ C1] ? mark_lock+0xc2/0x1220 [ 67.625953][ C1] ? mark_held_locks+0xf0/0xf0 [ 67.630690][ C1] lock_acquire+0x190/0x410 [ 67.635168][ C1] ? free_ioctx_users+0x2d/0x490 [ 67.640192][ C1] _raw_spin_lock_irq+0x60/0x80 [ 67.645028][ C1] ? free_ioctx_users+0x2d/0x490 [ 67.649957][ C1] free_ioctx_users+0x2d/0x490 [ 67.654710][ C1] ? rcu_dynticks_curr_cpu_in_eqs+0x54/0xb0 [ 67.660582][ C1] percpu_ref_switch_to_atomic_rcu+0x4c0/0x570 [ 67.666706][ C1] ? percpu_ref_exit+0xd0/0xd0 [ 67.671444][ C1] rcu_core+0x581/0x1560 [ 67.675664][ C1] ? __rcu_read_unlock+0x6b0/0x6b0 [ 67.680751][ C1] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 67.686285][ C1] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 67.692253][ C1] ? run_rebalance_domains+0x227/0x2d0 [ 67.697688][ C1] rcu_core_si+0x9/0x10 [ 67.701817][ C1] __do_softirq+0x262/0x98c [ 67.706298][ C1] ? sched_clock_cpu+0x1b/0x1b0 [ 67.711127][ C1] irq_exit+0x19b/0x1e0 [ 67.715340][ C1] smp_apic_timer_interrupt+0x1a3/0x610 [ 67.720855][ C1] apic_timer_interrupt+0xf/0x20 [ 67.725763][ C1] [ 67.728678][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 67.734027][ C1] Code: 38 c1 69 fa eb 8a 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 64 b8 64 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 54 b8 64 00 fb f4 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 5e a7 1c fa e8 69 [ 67.753602][ C1] RSP: 0018:ffff8880a98dfcd0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 [ 67.761982][ C1] RAX: 1ffffffff11e5db7 RBX: 0000000000000000 RCX: 0000000000000000 [ 67.769940][ C1] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffff8880a98d0bdc [ 67.777978][ C1] RBP: ffff8880a98dfd00 R08: ffff8880a98d0340 R09: 0000000000000000 [ 67.785924][ C1] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 [ 67.793882][ C1] R13: 0000000000000000 R14: 0000000000000060 R15: 0000000000000001 [ 67.801848][ C1] ? default_idle+0x4e/0x360 [ 67.806415][ C1] default_enter_idle+0x71/0xf0 [ 67.811236][ C1] cpuidle_enter_state+0xef/0xfb0 [ 67.816235][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 67.822466][