INFO: task kworker/1:4:16091 blocked for more than 143 seconds. Not tainted 5.5.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:4 D26936 16091 2 0x80004000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4214 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 linkwatch_event+0xf/0x70 net/core/link_watch.c:242 process_one_work+0x9af/0x1740 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:7:17483 blocked for more than 143 seconds. Not tainted 5.5.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:7 D29320 17483 2 0x80004000 Workqueue: events switchdev_deferred_process_work Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4214 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:74 process_one_work+0x9af/0x1740 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Showing all locks held in the system: 4 locks held by kworker/u4:2/74: 1 lock held by khungtaskd/1129: #0: ffffffff899a3fc0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5334 2 locks held by getty/9541: #0: ffff88809fe66090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000182b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9542: #0: ffff8880a75ef090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000183b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9543: #0: ffff8880a324d090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900017cb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9544: #0: ffff8880a5022090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000180b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9545: #0: ffff88809faff090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900017ab2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9546: #0: ffff888093a02090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000184b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9547: #0: ffff88821485e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900011642e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 3 locks held by kworker/u4:3/1773: #0: ffff8880ae837358 (&rq->lock){-.-.}, at: newidle_balance+0xa28/0xe80 kernel/sched/fair.c:10177 #1: ffffffff899a3fc0 (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:5729 #2: ffffffff899a3fc0 (rcu_read_lock){....}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:405 [inline] #2: ffffffff899a3fc0 (rcu_read_lock){....}, at: batadv_nc_worker+0xe3/0x760 net/batman-adv/network-coding.c:718 3 locks held by kworker/1:4/16091: #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2235 #1: ffffc900018e7dc0 ((linkwatch_work).work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239 #2: ffffffff8a4d5540 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/1:6/17480: #0: ffff88821505d928 ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff88821505d928 ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88821505d928 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff88821505d928 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff88821505d928 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff88821505d928 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff88821505d928 ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2235 #1: ffffc90001cc7dc0 ((addr_chk_work).work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239 #2: ffffffff8a4d5540 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/1:7/17483: #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2235 #1: ffffc900017e7dc0 (deferred_process_work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239 #2: ffffffff8a4d5540 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.5/4528: #0: ffffffff8a4d5540 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.5/4567: #0: ffffffff8a4d5540 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1129 Comm: khungtaskd Not tainted 5.5.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb11/0x10c0 kernel/hung_task.c:289 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1773 Comm: kworker/u4:3 Not tainted 5.5.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_purge_orig RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline] RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:2862 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:2881 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:2936 [inline] RIP: 0010:__lock_acquire+0x178a/0x4a00 kernel/locking/lockdep.c:3955 Code: 5b 4c 8b b5 48 ff ff ff 49 bc 00 00 00 00 00 fc ff df eb 06 48 83 eb 08 74 42 48 8d 7b 18 48 89 f8 48 c1 e8 03 42 80 3c 20 00 <0f> 85 c3 1e 00 00 48 8b 43 18 49 39 c6 0f 84 90 f1 ff ff 48 8d 7b RSP: 0018:ffffc90002c77a50 EFLAGS: 00000046 RAX: 1ffffffff15b5eeb RBX: ffffffff8adaf740 RCX: ffffffff815a9802 RDX: 1ffffffff165dbda RSI: 0000000000000008 RDI: ffffffff8adaf758 RBP: ffffc90002c77b68 R08: 0000000000007c52 R09: fffffbfff165f7b5 R10: ffff888095bbcaa8 R11: ffff888095bbc1c0 R12: dffffc0000000000 R13: ffffffff8a7be670 R14: 53adf9bb0f0eec0f R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 000000008f286000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 00000000000007ff DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4485 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x33/0x50 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:343 [inline] batadv_purge_orig_ref+0x189/0x1360 net/batman-adv/originator.c:1350 batadv_purge_orig+0x1b/0x70 net/batman-adv/originator.c:1379 process_one_work+0x9af/0x1740 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352