INFO: task syz-executor:4776 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21984 pid: 4776 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x1b3/0x920 fs/fs-writeback.c:2781 sync_filesystem+0x16d/0x220 fs/sync.c:64 generic_shutdown_super+0x6b/0x300 fs/super.c:448 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f904a6e3497 RSP: 002b:00007fffba482358 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f904a76308c RCX: 00007f904a6e3497 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffba482410 RBP: 00007fffba482410 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffba4834a0 R13: 00007f904a76308c R14: 0000000000017d84 R15: 00007fffba4834e0 Showing all locks held in the system: 4 locks held by kworker/u4:0/9: #0: ffff8880187a0938 ( (wq_completion)writeback ){+.+.}-{0:0} , at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90000ce7d00 ( (work_completion)(&(&wb->dwork)->work) ){+.+.}-{0:0} , at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff88807710a650 ( sb_internal #2 ){.+.+}-{0:0} , at: xfs_bmapi_convert_delalloc+0x1f1/0xd90 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffff88805d03e9e8 ( &xfs_nondir_ilock_class ){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x21e/0xd90 fs/xfs/libxfs/xfs_bmap.c:4578 2 locks held by kworker/0:1/13: 1 lock held by khungtaskd/27: #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:1/144: #0: ffff8880187a0938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000171fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff8880560f8650 ( sb_internal #2 ){.+.+}-{0:0} , at: xfs_bmapi_convert_delalloc+0x1f1/0xd90 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffff88805d15a668 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x21e/0xd90 fs/xfs/libxfs/xfs_bmap.c:4578 4 locks held by kworker/u4:2/154: #0: ffff8880187a0938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90002037d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0} , at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff8880545f4650 ( sb_internal #2 ){.+.+}-{0:0} , at: xfs_bmapi_convert_delalloc+0x1f1/0xd90 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffff88805d03cbe8 ( &xfs_nondir_ilock_class ){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x21e/0xd90 fs/xfs/libxfs/xfs_bmap.c:4578 4 locks held by kworker/u4:3/428: #0: ffff8880187a0938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000311fd00 ( (work_completion)(&(&wb->dwork)->work) ){+.+.}-{0:0} , at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff888018b88650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x1f1/0xd90 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffff88805d03ade8 ( &xfs_nondir_ilock_class ){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x21e/0xd90 fs/xfs/libxfs/xfs_bmap.c:4578 2 locks held by getty/3953: #0: ffff88814d06e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3} , at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 3 locks held by kworker/1:4/4235: #0: ffff88802aecb938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000303fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110 2 locks held by kworker/1:6/4237: #0: ffff888016872138 ((wq_completion)rcu_gp ){+.+.}-{0:0} , at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000304fd00 ( (work_completion)(&rew.rew_work) ){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 3 locks held by kworker/1:8/4239: #0: ffff888016870938 ( (wq_completion)events ){+.+.}-{0:0} , at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000306fd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d238988 ( rtnl_mutex ){+.+.}-{3:3} , at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 4 locks held by kworker/u4:5/4750: #0: ffff8880187a0938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000318fd00 ( (work_completion)(&(&wb->dwork)->work) ){+.+.}-{0:0} , at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff888078daa650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x1f1/0xd90 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffff88805d1580e8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x21e/0xd90 fs/xfs/libxfs/xfs_bmap.c:4578 2 locks held by syz-executor/4776: #0: ffff888078daa0e0 (&type->s_umount_key#54 ){+.+.}-{3:3} , at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffff88814735e7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff88814735e7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x197/0x920 fs/fs-writeback.c:2779 2 locks held by syz-executor/5056: #0: ffff888018b880e0 ( &type->s_umount_key #54 ){+.+.}-{3:3} , at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffff8881473747d8 ( &bdi->wb_switch_rwsem ){+.+.}-{3:3} , at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] , at: sync_inodes_sb+0x197/0x920 fs/fs-writeback.c:2779 2 locks held by syz-executor/5087: #0: ffff8880545f40e0 ( &type->s_umount_key #54 ){+.+.}-{3:3} , at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffff88814737a7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] ffff88814737a7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x197/0x920 fs/fs-writeback.c:2779 2 locks held by syz-executor/5150: #0: ffff88807710a0e0 ( &type->s_umount_key #54 ){+.+.}-{3:3} , at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffff8881473887d8 ( &bdi->wb_switch_rwsem ){+.+.}-{3:3} , at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] , at: sync_inodes_sb+0x197/0x920 fs/fs-writeback.c:2779 2 locks held by syz-executor/5185: #0: ffff8880560f80e0 ( &type->s_umount_key #54 ){+.+.}-{3:3} , at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffff88814738e7d8 ( &bdi->wb_switch_rwsem ){+.+.}-{3:3} , at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] , at: sync_inodes_sb+0x197/0x920 fs/fs-writeback.c:2779 3 locks held by syz-executor/5231: #0: ffffffff8d238988 ( rtnl_mutex ){+.+.}-{3:3} , at: rtnl_lock net/core/rtnetlink.c:72 [inline] , at: rtnetlink_rcv_msg+0x7a5/0xe90 net/core/rtnetlink.c:5681 #1: ffff88807b55d3e8 ( &wg->device_update_lock ){+.+.}-{3:3} , at: wg_open+0x223/0x420 drivers/net/wireguard/device.c:49 #2: ffffffff8c1211e8 ( rcu_state.exp_mutex ){+.+.}-{3:3} , at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] , at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 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: 7 Comm: kworker/0:0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: xfs-buf/loop1 xfs_buf_ioend_work RIP: 0010:scheduler_tick+0x1c3/0x4d0 kernel/sched/core.c:5320 Code: 4c 89 e8 48 c1 e8 03 80 3c 28 00 74 08 4c 89 ef e8 12 f3 69 00 41 bf 88 00 00 00 4d 03 7d 00 4c 89 f8 48 c1 e8 03 80 3c 28 00 <74> 08 4c 89 ff e8 f3 f2 69 00 48 89 df 48 8b 74 24 10 31 d2 41 ff RSP: 0018:ffffc90000007c48 EFLAGS: 00000046 RAX: 1ffffffff1778bfb RBX: ffff8880b903a340 RCX: ffffffff8eedce03 RDX: 1ffffffff1dda600 RSI: ffffffff8a0b2f00 RDI: ffffffff8a59e580 RBP: dffffc0000000000 R08: ffffffff8eed3008 R09: ffffffff8eed3018 R10: ffffffff8eed3010 R11: ffffffff8eed3003 R12: 1ffff11017207613 R13: ffff888017563c00 R14: ffffffff8bbcc820 R15: ffffffff8bbc5fd8 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcd7923cb8 CR3: 00000000245e5000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: update_process_times+0x1c7/0x200 kernel/time/timer.c:1823 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:console_trylock_spinning+0x2cd/0x350 kernel/printk/printk.c:1909 Code: 85 db 74 9d e8 64 a2 18 00 fb 31 c0 eb 48 e8 5a a2 18 00 e8 25 44 4a 08 48 85 db 74 d1 e8 4b a2 18 00 fb 48 c7 c7 a0 12 11 8c <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 68 c6 29 5f RSP: 0018:ffffc90000cc77a0 EFLAGS: 00000293 RAX: ffffffff815f29c5 RBX: 0000000000000200 RCX: ffff888017563b80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c1112a0 RBP: ffffc90000cc7870 R08: dffffc0000000000 R09: fffffbfff1ff7c41 R10: fffffbfff1ff7c41 R11: 1ffffffff1ff7c40 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffff92000198ef4 vprintk_emit+0xa7/0x150 kernel/printk/printk.c:2273 _printk+0xcc/0x110 kernel/printk/printk.c:2299 __xfs_printk fs/xfs/xfs_message.c:24 [inline] xfs_alert+0x188/0x280 fs/xfs/xfs_message.c:52 xfs_buf_verifier_error+0x1ae/0x290 fs/xfs/xfs_error.c:416 xfs_agf_read_verify+0x1cd/0x250 fs/xfs/libxfs/xfs_alloc.c:-1 xfs_buf_ioend+0x25c/0x6e0 fs/xfs/xfs_buf.c:1263 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287