INFO: task kworker/u4:2:33 blocked for more than 143 seconds. Not tainted 6.1.87-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:2 state:D stack:19872 pid:33 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189 f2fs_down_write fs/f2fs/f2fs.h:2176 [inline] f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428 f2fs_write_inode+0x4c3/0x540 fs/f2fs/inode.c:730 write_inode fs/fs-writeback.c:1460 [inline] __writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677 writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1974 wb_writeback+0x4b1/0xe10 fs/fs-writeback.c:2079 wb_check_background_flush fs/fs-writeback.c:2145 [inline] wb_do_writeback fs/fs-writeback.c:2233 [inline] wb_workfn+0xc9e/0x1020 fs/fs-writeback.c:2260 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d12ae50 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d12b650 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/28: #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 4 locks held by kworker/u4:2/33: #0: ffff888141ef6938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90000a9fd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff888027a920e0 (&type->s_umount_key#82){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88801eb31140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2176 [inline] #3: ffff88801eb31140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428 2 locks held by getty/3306: #0: ffff88814b362098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188 4 locks held by kworker/u4:7/3707: #0: ffff888012616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900048e7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e28dd50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:563 #3: ffffffff8e299fa8 (rtnl_mutex){+.+.}-{3:3}, at: fib_net_exit_batch+0x1c/0x90 net/ipv4/fib_frontend.c:1638 3 locks held by kworker/1:11/3986: #0: ffff88814b1cd538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90009147d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e299fa8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4114 3 locks held by kworker/1:13/3989: #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90009167d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e299fa8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 3 locks held by kworker/0:19/4217: #0: ffff88814b1cd538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000b22fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e299fa8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4114 3 locks held by kworker/0:21/4219: #0: ffff8880127fad38 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000b24fd20 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff888145712190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #2: ffff888145712190 (&dev->mutex){....}-{3:3}, at: usb_remote_wakeup+0x1f/0xf0 drivers/usb/core/hub.c:3787 2 locks held by kworker/0:32/4236: #0: ffff888012472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000ab17d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 5 locks held by syz-executor.0/5088: 2 locks held by kworker/u4:12/6017: 3 locks held by syz-executor.4/7844: #0: ffffffff8e2f9070 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860 #1: ffffffff8e2f8f28 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8e2f8f28 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x125/0xf70 net/netlink/genetlink.c:848 #2: ffffffff8e299fa8 (rtnl_mutex){+.+.}-{3:3}, at: wiphy_register+0x1e34/0x2cc0 net/wireless/core.c:960 1 lock held by syz-executor.3/7918: #0: ffffffff8e299fa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e299fa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118 2 locks held by syz-executor.0/8107: #0: ffffffff8e299fa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e299fa8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3487 #1: ffffffff8d130278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8d130278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 1 lock held by syz-executor.1/8122: #0: ffff88807a3880e0 (&type->s_umount_key#24/1){+.+.}-{3:3}, at: alloc_super+0x217/0x930 fs/super.c:228 1 lock held by syz-executor.2/8125: #0: ffffffff8d130278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] ffffffff8d130278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.87-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4421 Comm: kworker/1:18 Not tainted 6.1.87-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:kernel_text_address+0x3/0xd0 kernel/extable.c:95 Code: 93 c1 48 c7 c2 78 8d c6 8f 48 39 d3 0f 92 c2 20 ca 08 c2 0f b6 c2 5b c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 41 56 <53> 48 89 fb 48 c7 c0 00 00 00 81 bd 01 00 00 00 48 39 c7 72 0c 48 RSP: 0018:ffffc90013a57638 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff810058af RCX: 0000000080000001 RDX: dffffc0000000000 RSI: ffffc90013a50000 RDI: ffffffff810058af RBP: ffffc90013a57710 R08: ffffc90013a57f48 R09: ffffc90013a576d0 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88805a795940 R13: ffffffff81784a30 R14: dffffc0000000000 R15: 1ffff9200274aed9 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4528030d58 CR3: 000000005ca96000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000004 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __kernel_text_address+0x9/0x40 kernel/extable.c:79 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323 arch_stack_walk+0xf3/0x140 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674 skb_free_head net/core/skbuff.c:762 [inline] skb_release_data+0x5de/0x7a0 net/core/skbuff.c:791 skb_release_all net/core/skbuff.c:856 [inline] __kfree_skb net/core/skbuff.c:870 [inline] consume_skb+0xa3/0x140 net/core/skbuff.c:1035 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x75d/0xa90 drivers/net/netdevsim/dev.c:850 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308