[ 16.738602][ T3892] 8021q: adding VLAN 0 to HW filter on device bond0 [ 16.743369][ T3892] eql: remember to turn off Van-Jacobson compression on your slave devices [ 16.788477][ T11] gvnic 0000:00:00.0 enp0s0: Device link is up. [ 16.793950][ T1965] IPv6: ADDRCONF(NETDEV_CHANGE): enp0s0: link becomes ready Starting sshd: OK syzkaller Warning: Permanently added '10.128.10.45' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 39.948009][ T4306] [ 39.948612][ T4306] ====================================================== [ 39.950180][ T4306] WARNING: possible circular locking dependency detected [ 39.951748][ T4306] 6.1.16-syzkaller #0 Not tainted [ 39.952951][ T4306] ------------------------------------------------------ [ 39.954513][ T4306] syz-executor181/4306 is trying to acquire lock: [ 39.955948][ T4306] ffff0000ccd080a8 ((&sq->pending_timer)){+.-.}-{0:0}, at: del_timer_sync+0x74/0x210 [ 39.958107][ T4306] [ 39.958107][ T4306] but task is already holding lock: [ 39.959782][ T4306] ffff800019965b30 (&blkcg->lock){....}-{2:2}, at: blkcg_deactivate_policy+0x1b8/0x4bc [ 39.962084][ T4306] [ 39.962084][ T4306] which lock already depends on the new lock. [ 39.962084][ T4306] [ 39.964422][ T4306] [ 39.964422][ T4306] the existing dependency chain (in reverse order) is: [ 39.966535][ T4306] [ 39.966535][ T4306] -> #2 (&blkcg->lock){....}-{2:2}: [ 39.968282][ T4306] _raw_spin_lock+0x54/0x6c [ 39.969412][ T4306] blkg_create+0x9f4/0x1158 [ 39.970570][ T4306] blkcg_init_disk+0xe4/0x32c [ 39.971828][ T4306] __alloc_disk_node+0x26c/0x484 [ 39.973104][ T4306] __blk_alloc_disk+0x40/0xbc [ 39.974310][ T4306] brd_alloc+0x2ac/0x5c8 [ 39.975412][ T4306] brd_init+0x108/0x1c4 [ 39.976465][ T4306] do_one_initcall+0x310/0xda4 [ 39.977687][ T4306] do_initcall_level+0x154/0x214 [ 39.978918][ T4306] do_initcalls+0x58/0xac [ 39.980063][ T4306] do_basic_setup+0x8c/0xa0 [ 39.981280][ T4306] kernel_init_freeable+0x3a4/0x528 [ 39.982644][ T4306] kernel_init+0x24/0x29c [ 39.983796][ T4306] ret_from_fork+0x10/0x20 [ 39.984945][ T4306] [ 39.984945][ T4306] -> #1 (&q->queue_lock){..-.}-{2:2}: [ 39.986759][ T4306] _raw_spin_lock_irq+0x70/0x9c [ 39.988014][ T4306] throtl_pending_timer_fn+0x104/0xdcc [ 39.989390][ T4306] call_timer_fn+0x270/0xcf4 [ 39.990574][ T4306] __run_timers+0x554/0x718 [ 39.991737][ T4306] run_timer_softirq+0x7c/0x114 [ 39.993058][ T4306] __do_softirq+0x37c/0xff4 [ 39.994285][ T4306] ____do_softirq+0x14/0x20 [ 39.995466][ T4306] call_on_irq_stack+0x2c/0x54 [ 39.996748][ T4306] do_softirq_own_stack+0x20/0x2c [ 39.998095][ T4306] __irq_exit_rcu+0x28c/0x534 [ 39.999298][ T4306] irq_exit_rcu+0x14/0x84 [ 40.000402][ T4306] el1_interrupt+0x38/0x68 [ 40.001527][ T4306] el1h_64_irq_handler+0x18/0x24 [ 40.002807][ T4306] el1h_64_irq+0x64/0x68 [ 40.003962][ T4306] arch_local_irq_enable+0xc/0x18 [ 40.005233][ T4306] default_idle_call+0x68/0xdc [ 40.006455][ T4306] do_idle+0x1e0/0x514 [ 40.007505][ T4306] cpu_startup_entry+0x24/0x28 [ 40.008794][ T4306] secondary_start_kernel+0x19c/0x1c4 [ 40.010191][ T4306] __secondary_switched+0xb0/0xb4 [ 40.011558][ T4306] [ 40.011558][ T4306] -> #0 ((&sq->pending_timer)){+.-.}-{0:0}: [ 40.013508][ T4306] __lock_acquire+0x3338/0x764c [ 40.014834][ T4306] lock_acquire+0x300/0x8e4 [ 40.016045][ T4306] del_timer_sync+0x9c/0x210 [ 40.017236][ T4306] throtl_pd_free+0x20/0x48 [ 40.018391][ T4306] blkcg_deactivate_policy+0x2d8/0x4bc [ 40.019801][ T4306] blk_throtl_exit+0x9c/0x13c [ 40.021001][ T4306] blkcg_exit_disk+0x4c/0x5c [ 40.022216][ T4306] disk_release+0x170/0x2d8 [ 40.023404][ T4306] device_release+0x8c/0x1ac [ 40.024580][ T4306] kobject_put+0x2a8/0x41c [ 40.025738][ T4306] put_device+0x28/0x40 [ 40.026777][ T4306] put_disk+0x4c/0x64 [ 40.027812][ T4306] loop_control_ioctl+0x534/0x650 [ 40.029121][ T4306] __arm64_sys_ioctl+0x14c/0x1c8 [ 40.030450][ T4306] invoke_syscall+0x98/0x2c0 [ 40.031652][ T4306] el0_svc_common+0x138/0x258 [ 40.032846][ T4306] do_el0_svc+0x64/0x218 [ 40.033975][ T4306] el0_svc+0x58/0x168 [ 40.034992][ T4306] el0t_64_sync_handler+0x84/0xf0 [ 40.036257][ T4306] el0t_64_sync+0x18c/0x190 [ 40.037428][ T4306] [ 40.037428][ T4306] other info that might help us debug this: [ 40.037428][ T4306] [ 40.039737][ T4306] Chain exists of: [ 40.039737][ T4306] (&sq->pending_timer) --> &q->queue_lock --> &blkcg->lock [ 40.039737][ T4306] [ 40.042758][ T4306] Possible unsafe locking scenario: [ 40.042758][ T4306] [ 40.044445][ T4306] CPU0 CPU1 [ 40.045671][ T4306] ---- ---- [ 40.046941][ T4306] lock(&blkcg->lock); [ 40.047955][ T4306] lock(&q->queue_lock); [ 40.049626][ T4306] lock(&blkcg->lock); [ 40.051171][ T4306] lock((&sq->pending_timer)); [ 40.052304][ T4306] [ 40.052304][ T4306] *** DEADLOCK *** [ 40.052304][ T4306] [ 40.054196][ T4306] 3 locks held by syz-executor181/4306: [ 40.055519][ T4306] #0: ffff0000cccf0b28 (&q->blkcg_mutex){+.+.}-{3:3}, at: blkcg_deactivate_policy+0xfc/0x4bc [ 40.057914][ T4306] #1: ffff0000cccf0918 (&q->queue_lock){..-.}-{2:2}, at: blkcg_deactivate_policy+0x108/0x4bc [ 40.060293][ T4306] #2: ffff800019965b30 (&blkcg->lock){....}-{2:2}, at: blkcg_deactivate_policy+0x1b8/0x4bc [ 40.062548][ T4306] [ 40.062548][ T4306] stack backtrace: [ 40.063929][ T4306] CPU: 1 PID: 4306 Comm: syz-executor181 Not tainted 6.1.16-syzkaller #0 [ 40.065806][ T4306] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 [ 40.068098][ T4306] Call trace: [ 40.068848][ T4306] dump_backtrace+0x1c8/0x1f4 [ 40.069938][ T4306] show_stack+0x2c/0x3c [ 40.070863][ T4306] dump_stack_lvl+0x108/0x170 [ 40.072000][ T4306] dump_stack+0x1c/0x5c [ 40.072975][ T4306] print_circular_bug+0x150/0x1b8 [ 40.074169][ T4306] check_noncircular+0x2cc/0x378 [ 40.075338][ T4306] __lock_acquire+0x3338/0x764c [ 40.076441][ T4306] lock_acquire+0x300/0x8e4 [ 40.077438][ T4306] del_timer_sync+0x9c/0x210 [ 40.078543][ T4306] throtl_pd_free+0x20/0x48 [ 40.079556][ T4306] blkcg_deactivate_policy+0x2d8/0x4bc [ 40.080819][ T4306] blk_throtl_exit+0x9c/0x13c [ 40.081923][ T4306] blkcg_exit_disk+0x4c/0x5c [ 40.083017][ T4306] disk_release+0x170/0x2d8 [ 40.084003][ T4306] device_release+0x8c/0x1ac [ 40.085043][ T4306] kobject_put+0x2a8/0x41c [ 40.086088][ T4306] put_device+0x28/0x40 [ 40.087085][ T4306] put_disk+0x4c/0x64 [ 40.088071][ T4306] loop_control_ioctl+0x534/0x650 [ 40.089191][ T4306] __arm64_sys_ioctl+0x14c/0x1c8 [ 40.090350][ T4306] invoke_syscall+0x98/0x2c0 [ 40.091390][ T4306] el0_svc_common+0x138/0x258 [ 40.092443][ T4306] do_el0_svc+0x64/0x218 [ 40.093436][ T4306] el0_svc+0x58/0x168 [ 40.094328][ T4306] el0t_64_sync_handler+0x84/0xf0 [ 40.095465][ T4306] el0t_64_sync+0x18c/0x190