INFO: task syz-executor:5131 blocked for more than 143 seconds. Not tainted 6.1.119-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20792 pid:5131 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 wb_wait_for_completion+0x162/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x28f/0xb10 fs/fs-writeback.c:2739 sync_filesystem+0x16b/0x220 fs/sync.c:64 generic_shutdown_super+0x6b/0x340 fs/super.c:474 kill_block_super+0x7a/0xe0 fs/super.c:1470 deactivate_locked_super+0xa0/0x110 fs/super.c:332 cleanup_mnt+0x490/0x520 fs/namespace.c:1186 task_work_run+0x246/0x300 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xa73/0x26a0 kernel/exit.c:871 do_group_exit+0x202/0x2b0 kernel/exit.c:1021 __do_sys_exit_group kernel/exit.c:1032 [inline] __se_sys_exit_group kernel/exit.c:1030 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1030 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f048a17ff19 RSP: 002b:00007ffdb6d27688 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f048a1f3884 RCX: 00007f048a17ff19 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 000000000000000c R08: 00007ffdb6d25426 R09: 00007ffdb6d28940 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdb6d28940 R13: 00007f048a1f3824 R14: 000055556cc124a8 R15: 00007ffdb6d29a00 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b110 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32b910 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8d32af40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32af40 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32af40 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 4 locks held by kworker/u4:2/33: #0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90000aa7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4fe3d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:566 #3: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: wg_destruct+0x21/0x2f0 drivers/net/wireguard/device.c:246 2 locks held by getty/4013: #0: ffff88807ddf0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 2 locks held by kworker/u4:8/4497: #0: ffff8880b8e3a9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #1: ffff8880b8e27788 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x419/0x790 kernel/sched/psi.c:999 3 locks held by kworker/u4:11/4833: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90003307d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 2 locks held by syz-executor/5131: #0: ffff888028b4a0e0 (&type->s_umount_key#89){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362 #1: ffff8880252c27d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8880252c27d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x270/0xb10 fs/fs-writeback.c:2737 3 locks held by kworker/1:14/5637: #0: ffff888030321d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90003477d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4115 2 locks held by kworker/1:19/5642: #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90003627d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 2 locks held by kworker/u4:15/5658: #0: ffff88801c6f9938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900036b7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 3 locks held by kworker/0:16/5892: #0: ffff888030321d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004857d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4115 1 lock held by segctord/6174: 1 lock held by syz.9.547/7336: #0: ffff888028b4a0e0 (&type->s_umount_key#89){++++}-{3:3}, at: user_get_super+0x11a/0x250 fs/super.c:889 1 lock held by syz-executor/7461: #0: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6147 1 lock held by syz-executor/7486: #0: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6147 1 lock held by syz-executor/7660: #0: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6147 2 locks held by syz.6.589/7804: #0: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e50a768 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3492 #1: ffffffff8d330538 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8d330538 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.119-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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+0x1ae/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:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6174 Comm: segctord Not tainted 6.1.119-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:filter_irq_stacks+0x0/0xa0 kernel/stacktrace.c:391 Code: f9 80 e1 07 80 c1 03 38 c1 0f 8c 61 ff ff ff 4c 89 ff e8 43 bc 69 00 e9 54 ff ff ff e8 79 6a 39 09 66 0f 1f 84 00 00 00 00 00 <55> 41 57 41 56 41 55 41 54 53 85 f6 74 72 49 89 fe 41 89 f4 45 31 RSP: 0018:ffffc90003907340 EFLAGS: 00000286 RAX: b83b493b85c15a00 RBX: 0000000000000001 RCX: 0000000000000c40 RDX: 0000000000000000 RSI: 000000000000000a RDI: ffffc900039073b0 RBP: ffffc900039075e0 R08: 0000000000000001 R09: ffffc90003907310 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000c40 R13: 0000000000000c40 R14: 0000000000000000 R15: ffffc900039073b0 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f54ab30cab8 CR3: 0000000027c63000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __stack_depot_save+0x36/0x470 lib/stackdepot.c:439 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x60/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422 nilfs_segbuf_new+0x4a/0x260 fs/nilfs2/segbuf.c:38 nilfs_segctor_begin_construction fs/nilfs2/segment.c:1318 [inline] nilfs_segctor_do_construct+0xb84/0x7100 fs/nilfs2/segment.c:2081 nilfs_segctor_construct+0x181/0x6a0 fs/nilfs2/segment.c:2451 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2559 [inline] nilfs_segctor_thread+0x552/0x11a0 fs/nilfs2/segment.c:2643 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295