INFO: task kworker/u8:2:35 blocked for more than 143 seconds. Not tainted 6.10.0-rc2-syzkaller-00761-g3ec8d7572a69 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:2 state:D stack:21816 pid:35 tgid:35 ppid:2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4733 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 3 locks held by kworker/u8:2/35: #0: ffff888029e9a148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888029e9a148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90000ab7d00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90000ab7d00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8f5e7648 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4733 3 locks held by kworker/1:1/45: 2 locks held by getty/4857: #0: ffff88802a6f90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f162f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201 2 locks held by syz-executor174/5123: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 30 Comm: khungtaskd Not tainted 6.10.0-rc2-syzkaller-00761-g3ec8d7572a69 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfde/0x1020 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 45 Comm: kworker/1:1 Not tainted 6.10.0-rc2-syzkaller-00761-g3ec8d7572a69 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Workqueue: events_power_efficient gc_worker RIP: 0010:debug_lockdep_rcu_enabled+0x21/0x40 kernel/rcu/update.c:321 Code: 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 31 c0 83 3d 27 bd 25 04 00 74 1e 83 3d 76 ee 25 04 00 74 15 65 48 8b 0c 25 00 d5 03 00 <31> c0 83 b9 dc 0a 00 00 00 0f 94 c0 c3 cc cc cc cc 66 2e 0f 1f 84 RSP: 0018:ffffc90000b57938 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffffffff89a2494b RCX: ffff88801b2d8000 RDX: 0000000000000000 RSI: 000000000000061c RDI: ffffffff8ccabca0 RBP: ffffc90000b57a50 R08: ffffffff8fad9aaf R09: 1ffffffff1f5b355 R10: dffffc0000000000 R11: fffffbfff1f5b356 R12: 0000000000000000 R13: dffffc0000000000 R14: 000000000000061c R15: 1ffff9200016af30 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561278a0c600 CR3: 00000000599b4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __might_resched+0x90/0x780 kernel/sched/core.c:10158 gc_worker+0xdda/0x1530 net/netfilter/nf_conntrack_core.c:1564 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.248 msecs