INFO: task syz-executor:4146 blocked for more than 143 seconds. Not tainted 5.15.168-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20832 pid: 4146 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x293/0xab0 fs/fs-writeback.c:2770 sync_filesystem+0x16b/0x220 fs/sync.c:64 generic_shutdown_super+0x6b/0x310 fs/super.c:448 kill_block_super+0x7a/0xe0 fs/super.c:1427 deactivate_locked_super+0xa0/0x110 fs/super.c:335 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143 task_work_run+0x129/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f27c9b50327 RSP: 002b:00007fffd05d56e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f27c9bc1134 RCX: 00007f27c9b50327 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffd05d57a0 RBP: 00007fffd05d57a0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffd05d6820 R13: 00007f27c9bc1134 R14: 0000000000015659 R15: 00007fffd05d6860 Showing all locks held in the system: 3 locks held by kworker/0:1/13: #0: ffff88802939bd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90000d27d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8da32188 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4113 1 lock held by khungtaskd/27: #0: ffffffff8c91fc20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:3/1151: #0: ffff8880171cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90004e1fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8da265d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:561 #3: ffffffff8da32188 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0xa4f/0xc40 net/core/dev.c:10660 1 lock held by klogd/3016: 2 locks held by getty/3332: #0: ffff88814b858098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc9000208e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 3 locks held by kworker/0:3/3559: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900020c7d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8c9241e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #2: ffffffff8c9241e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 3 locks held by kworker/1:3/3573: #0: ffff88802939bd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90002e57d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8da32188 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4113 2 locks held by kworker/0:5/3616: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900032f7d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:6/3617: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003317d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 4 locks held by kworker/u4:5/3633: #0: ffff8881447ac938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003787d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff888078b4c650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x20f/0x1180 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffff88805c046268 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x23c/0x1180 fs/xfs/libxfs/xfs_bmap.c:4578 2 locks held by kworker/0:7/3710: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900011efd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:8/3951: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900033b7d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:9/3984: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900033c7d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:11/3988: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003427d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by syz-executor/4146: #0: ffff888078b4c0e0 (&type->s_umount_key#75){+.+.}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365 #1: ffff8881475847d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881475847d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2768 2 locks held by kworker/0:13/4226: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003747d20 ( (work_completion)(&pwq->unbound_release_work) ){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:14/4227: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0} , at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003757d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:15/4228: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003777d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:16/4229: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003017d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:17/4230: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900032a7d20 ( (work_completion)(&pwq->unbound_release_work) ){+.+.}-{0:0} , at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/1:12/4279: #0: ffff888017072138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90002367d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 3 locks held by kworker/u4:9/4572: #0: ffff888017079138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90002fe7d20 ( (linkwatch_work).work ){+.+.}-{0:0} , at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8da32188 ( rtnl_mutex ){+.+.}-{3:3} , at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 2 locks held by kworker/0:18/5407: #0: ffff888017070938 ( (wq_completion)events ){+.+.}-{0:0} , at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003217d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:19/5408: #0: ffff888017070938 ( (wq_completion)events ){+.+.}-{0:0} , at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900031a7d20 ( (work_completion)(&pwq->unbound_release_work) ){+.+.}-{0:0} , at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/0:20/5409: #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003647d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 1 lock held by syz-executor/6222: #0: ffffffff8c9240f0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:4039 1 lock held by syz-executor/6472: #0: ffffffff8da32188 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8da32188 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5644 2 locks held by syz-executor/6583: #0: ffffffff8da32188 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8da32188 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5644 #1: ffffffff8c9241e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] ffffffff8c9241e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 4 locks held by syz.4.639/6597: #0: ffff888073eca0e0 (&type->s_umount_key#79){+.+.}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365 #1: ffffffff8ce023c8 (uuid_mutex){+.+.}-{3:3}, at: btrfs_close_devices+0xbc/0x5c0 fs/btrfs/volumes.c:1231 #2: ffff8880208f8518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912 #3: ffff88814757d468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070 2 locks held by syz.3.643/6610: #0: ffffffff8da265d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x378/0x5d0 net/core/net_namespace.c:472 #1: ffffffff8da32188 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x80/0x270 net/ipv4/nexthop.c:3607 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.168-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+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3613 Comm: kworker/0:4 Not tainted 5.15.168-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: xfs-buf/loop3 xfs_buf_ioend_work RIP: 0010:io_serial_in+0x72/0xb0 drivers/tty/serial/8250/8250_port.c:461 Code: a4 96 04 fd 89 e9 41 d3 e6 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 55 60 4e fd 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d c3 89 e9 80 e1 07 38 c1 7c ad 48 89 ef RSP: 0018:ffffc900032c73f0 EFLAGS: 00000002 RAX: 1ffffffff2d72000 RBX: ffffffff96b90100 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020 RBP: 0000000000000000 R08: ffffffff847bdc82 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 1ffffffff2d7206d R13: ffffffff96b900c0 R14: 00000000000003fd R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ba95622030 CR3: 00000000243f2000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_in drivers/tty/serial/8250/8250.h:116 [inline] wait_for_xmitr+0xec/0x260 drivers/tty/serial/8250/8250_port.c:2069 serial8250_console_putchar+0x19/0x50 drivers/tty/serial/8250/8250_port.c:3301 uart_console_write+0xa9/0x100 drivers/tty/serial/serial_core.c:1979 serial8250_console_write+0xc8e/0x1180 drivers/tty/serial/8250/8250_port.c:3378 console_unlock+0xced/0x12b0 kernel/printk/printk.c:2744 vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274 _printk+0xd1/0x120 kernel/printk/printk.c:2299 __xfs_printk fs/xfs/xfs_message.c:24 [inline] xfs_alert+0x1c8/0x320 fs/xfs/xfs_message.c:52 xfs_buf_verifier_error+0x1b0/0x290 fs/xfs/xfs_error.c:416 xfs_allocbt_read_verify+0x52/0xc0 xfs_buf_ioend+0x26a/0x6e0 fs/xfs/xfs_buf.c:1263 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287