INFO: task jbd2/sda1-8:2815 blocked in I/O wait for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jbd2/sda1-8 state:D stack:25560 pid:2815 tgid:2815 ppid:2 task_flags:0x240040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1138/0x47e0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 io_schedule+0x8a/0xf0 kernel/sched/core.c:8110 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:105 [inline] __wait_on_buffer+0x64/0x70 fs/buffer.c:123 wait_on_buffer include/linux/buffer_head.h:420 [inline] journal_wait_on_commit_record fs/jbd2/commit.c:171 [inline] jbd2_journal_commit_transaction+0x494c/0x6870 fs/jbd2/commit.c:910 kjournald2+0x200/0x760 fs/jbd2/journal.c:201 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 3 locks held by kworker/0:1/11: #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc900000bfd18 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffffffff896ea4a8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311 8 locks held by kworker/1:0/23: 3 locks held by kworker/1:1/28: 1 lock held by khungtaskd/30: #0: ffffffff896de960 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff896de960 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff896de960 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/2916: #0: ffff888112ba00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000452e8 ( &ldata->atomic_read_lock ){+.+.}-{4:4} , at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211 2 locks held by kworker/1:2/5226: 2 locks held by kworker/1:4/5239: 4 locks held by kworker/1:7/6401: 4 locks held by kworker/u8:3/13220: 1 lock held by syz-executor/13528: #0: ffffffff896ea4a8 ( rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 2 locks held by syz-executor/13538: #0: ffffffff8aadc468 ( pernet_ops_rwsem ){++++}-{4:4} , at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575 #1: ffffffff8aaf4fe0 ( rtnl_mutex){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2102 2 locks held by syz-executor/13549: #0: ffffffff8aadc468 ( pernet_ops_rwsem ){++++}-{4:4} , at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575 #1: ffffffff8aaf4fe0 ( rtnl_mutex){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2102 2 locks held by syz-executor/13551: #0: ffffffff8aadc468 ( pernet_ops_rwsem){++++}-{4:4} , at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575 #1: ffffffff8aaf4fe0 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2102 2 locks held by syz-executor/13568: 1 lock held by syz-executor/13578: #0: ffffffff8aaf4fe0 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 1 lock held by syz-executor/13582: #0: ffffffff8aaf4fe0 ( rtnl_mutex){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 1 lock held by syz-executor/13587: #0: ffffffff8aaf4fe0 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 1 lock held by syz-executor/13589: #0: ffffffff8aaf4fe0 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 1 lock held by syz-executor/13594: #0: ffffffff8aaf4fe0 ( rtnl_mutex){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+0x69a/0xc80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: yealink 5-1:36.0: unexpected response 0 yealink 5-1:36.0: urb_ctl_callback - urb status -71 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 23 Comm: kworker/1:0 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:402 Code: ef 8f fe 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c c3 cc cc cc cc e8 a8 aa f5 fe eb a2 e8 31 ab RSP: 0000:ffffc900001a84a8 EFLAGS: 00000006 RAX: dffffc0000000005 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: ffffffff8322f5d0 RDI: ffffffff941da800 RBP: ffffffff941da7c0 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff941daa80 R14: ffffffff941da810 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8882687a5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005614f91c14e0 CR3: 0000000116eba000 CR4: 00000000003506f0 Call Trace: serial_port_in include/linux/serial_core.h:806 [inline] serial8250_console_write+0x246/0x1900 drivers/tty/serial/8250/8250_port.c:3324 console_emit_next_record kernel/printk/printk.c:3183 [inline] console_flush_one_record+0x790/0xe50 kernel/printk/printk.c:3269 console_flush_all kernel/printk/printk.c:3343 [inline] __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3413 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479 dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4930 dev_printk_emit+0xd2/0x10d drivers/base/core.c:4941 __dev_printk+0xcb/0x100 drivers/base/core.c:4953 _dev_err+0xef/0x127 drivers/base/core.c:4996 urb_ctl_callback.cold+0x41/0x8c drivers/input/misc/yealink.c:456 __usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741 dummy_timer+0xda1/0x36c0 drivers/usb/gadget/udc/dummy_hcd.c:2005 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x470/0xa00 kernel/time/hrtimer.c:1994 hrtimer_run_softirq+0x17d/0x2c0 kernel/time/hrtimer.c:2011 handle_softirqs+0x1dd/0x9e0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x160/0x210 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:unwind_next_frame+0x47/0x2090 arch/x86/kernel/unwind_orc.c:709 Code: fd 41 54 55 53 48 83 ec 38 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 42 0b 00 00 41 8b 5d 00 31 ed 85 db 75 15 48 83 c4 38 89 e8 5b <5d> 41 5c 41 5d 41 5e 41 5f e9 cb 85 01 06 48 b8 00 00 00 00 00 fc RSP: 0000:ffffc9000018f628 EFLAGS: 00000292 RAX: 0000000000000001 RBX: ffffc9000018f658 RCX: ffffc9000018f5ac RDX: 0000000000000000 RSI: ffffffff890a9792 RDI: ffff88810268847c RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000007 R10: 0000000000000200 R11: 000000000000663c R12: ffffc9000018f6a8 R13: ffffc9000018f658 R14: ffffc9000018ff58 R15: ffffc9000018f68c arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x162/0x1e0 mm/page_owner.c:165 __reset_page_owner+0x84/0x190 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] __free_frozen_pages+0x6d8/0xf60 mm/page_alloc.c:2938 vfree mm/vmalloc.c:3472 [inline] vfree+0x15f/0x8d0 mm/vmalloc.c:3436 kcov_put kernel/kcov.c:442 [inline] kcov_put+0x2a/0x40 kernel/kcov.c:438 hub_event+0xdc6/0x4af0 drivers/usb/core/hub.c:5998 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314 process_scheduled_works kernel/workqueue.c:3397 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245