INFO: task syz.3.719:8928 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.719 state:D stack:27480 pid:8928 tgid:8927 ppid:5617 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820 sync_bdevs+0x153/0x480 block/bdev.c:1296 ksys_sync+0xb0/0xf0 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7c6479ce59 RSP: 002b:00007f7c655cf028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f7c64a15fa0 RCX: 00007f7c6479ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f7c64a15fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7c64a16038 R14: 00007f7c64a15fa0 R15: 00007ffcd0e6fa38 INFO: task syz.3.719:8930 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.719 state:D stack:29032 pid:8930 tgid:8927 ppid:5617 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820 sync_bdevs+0x153/0x480 block/bdev.c:1296 ksys_sync+0xb0/0xf0 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7c6479ce59 RSP: 002b:00007f7c655ae028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f7c64a16090 RCX: 00007f7c6479ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f7c64a16090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7c64a16128 R14: 00007f7c64a16090 R15: 00007ffcd0e6fa38 INFO: task syz.3.719:8933 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.719 state:D stack:28136 pid:8933 tgid:8927 ppid:5617 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820 sync_bdevs+0x153/0x480 block/bdev.c:1296 ksys_sync+0xb0/0xf0 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7c6479ce59 RSP: 002b:00007f7c6558d028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f7c64a16180 RCX: 00007f7c6479ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f7c64a16180 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7c64a16218 R14: 00007f7c64a16180 R15: 00007ffcd0e6fa38 INFO: task syz.3.719:8934 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.719 state:D stack:28136 pid:8934 tgid:8927 ppid:5617 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820 sync_bdevs+0x153/0x480 block/bdev.c:1296 ksys_sync+0xb0/0xf0 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7c6479ce59 RSP: 002b:00007f7c625f4028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f7c64a16270 RCX: 00007f7c6479ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f7c64a16270 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7c64a16308 R14: 00007f7c64a16270 R15: 00007ffcd0e6fa38 INFO: task syz.3.719:8936 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.719 state:D stack:28456 pid:8936 tgid:8927 ppid:5617 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820 sync_bdevs+0x153/0x480 block/bdev.c:1296 ksys_sync+0xb0/0xf0 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7c6479ce59 RSP: 002b:00007f7c621d1028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f7c64a16360 RCX: 00007f7c6479ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f7c64a16360 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7c64a163f8 R14: 00007f7c64a16360 R15: 00007ffcd0e6fa38 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: #0: ffff88803483f940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc90000117d08 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4746 1 lock held by khungtaskd/31: #0: ffffffff8e7e5620 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e7e5620 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e7e5620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:3/48: #0: ffff88801bb23140 ((wq_completion)tc_filter_workqueue){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc90000b97d08 ((work_completion)(&(rwork)->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: fw_delete_filter_work+0x1b/0x2c0 net/sched/cls_fw.c:131 3 locks held by kworker/u8:8/3282: #0: ffff88813fe94140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc9000f4ffd08 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:313 1 lock held by klogd/4973: #0: ffff8880b843b2e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:660 [inline] #0: ffff8880b843b2e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:644 2 locks held by getty/5370: #0: ffff8880348e10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211 5 locks held by kworker/1:8/6068: #0: ffff888022ee6540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc90005667d08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffff88802b2eb1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline] #2: ffff88802b2eb1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff8880351301d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline] #3: ffff8880351301d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076 #4: ffff888028a0c060 (hcd->bandwidth_mutex){+.+.}-{4:4}, at: usb_set_configuration+0x23d/0x1c60 drivers/usb/core/message.c:2135 2 locks held by syz.1.196/6686: #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3438 #1: ffffffff8e7f1168 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 1 lock held by udevd/7612: #0: ffff888028204350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:953 1 lock held by syz-executor/7644: #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3438 1 lock held by syz.3.719/8928: #0: ffff888028204350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.3.719/8930: #0: ffff888028204350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.3.719/8933: #0: ffff888028204350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.3.719/8934: #0: ffff888028204350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.3.719/8936: #0: ffff888028204350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 5 locks held by kworker/u8:12/9706: 1 lock held by syz.4.1131/10572: #0: ffff888028204350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:953 1 lock held by syz.2.1168/10723: #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3438 4 locks held by syz-executor/10748: #0: ffff888038d9cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0xb0 net/bluetooth/hci_core.c:500 #1: ffff888038d9c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x35c/0x1240 net/bluetooth/hci_sync.c:5359 #2: ffffffff90889980 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline] #2: ffffffff90889980 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x280 net/bluetooth/hci_conn.c:2734 #3: ffff8880237682f8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x95/0x710 net/bluetooth/l2cap_core.c:1777 1 lock held by syz.6.1176/10753: #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3438 1 lock held by syz.1.1177/10761: #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff90602ba0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3438 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xcb1/0x1030 kernel/hung_task.c:561 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 16 Comm: rcu_preempt Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:memory_is_nonzero mm/kasan/generic.c:114 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline] RIP: 0010:kasan_check_range+0x6e/0x1e0 mm/kasan/generic.c:200 Code: 4c 8d 54 37 ff 48 89 fd 48 b8 00 00 00 00 00 fc ff df 4d 89 d1 48 c1 ed 03 49 c1 e9 03 48 01 c5 49 01 c1 48 89 e8 49 8d 59 01 <48> 89 da 48 29 ea 48 83 fa 10 0f 8e db 00 00 00 41 89 eb 41 83 e3 RSP: 0018:ffffc90000157bf8 EFLAGS: 00000082 RAX: fffffbfff21ae02a RBX: fffffbfff21ae02b RCX: ffffffff8210d785 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90d70150 RBP: fffffbfff21ae02a R08: 0000000000000000 R09: fffffbfff21ae02a R10: ffffffff90d70157 R11: ffffffff8e7f0ab9 R12: ffffc90000157d10 R13: ffffffff8e7f0f58 R14: 0000000000000000 R15: 1ffff9200002af96 FS: 0000000000000000(0000) GS:ffff888124386000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5387dbbdf4 CR3: 000000000e596000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read include/linux/instrumented.h:82 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:649 [inline] cpu_online include/linux/cpumask.h:1231 [inline] trace_irq_disable include/trace/events/preemptirq.h:36 [inline] trace_hardirqs_off_finish kernel/trace/trace_preemptirq.c:95 [inline] trace_hardirqs_off+0x65/0x180 kernel/trace/trace_preemptirq.c:90 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:130 [inline] _raw_spin_lock_irqsave+0x52/0x60 kernel/locking/spinlock.c:166 prepare_to_swait_event+0x1f/0x4a0 kernel/sched/swait.c:108 rcu_gp_fqs_loop+0x1c0/0x900 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245