INFO: task kworker/1:1:42 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:1 state:D stack:17920 pid:42 tgid:42 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: xfs-sync/loop4 xfs_flush_inodes_worker
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5340 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
wb_wait_for_completion+0x3e8/0x790 fs/fs-writeback.c:227
sync_inodes_sb+0x1de/0xbd0 fs/fs-writeback.c:2925
xfs_flush_inodes_worker+0x61/0x80 fs/xfs/xfs_super.c:667
process_one_work+0x949/0x1650 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0xb46/0x1140 kernel/workqueue.c:3443
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task syz-executor:5838 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21056 pid:5838 tgid:5838 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5340 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
wb_wait_for_completion+0x3e8/0x790 fs/fs-writeback.c:227
__writeback_inodes_sb_nr+0x24b/0x2c0 fs/fs-writeback.c:2839
sync_filesystem+0xa3/0x230 fs/sync.c:54
ovl_sync_fs+0x12f/0x160 fs/overlayfs/super.c:262
sync_filesystem+0x1cf/0x230 fs/sync.c:66
generic_shutdown_super+0x77/0x2d0 fs/super.c:625
kill_anon_super+0x3b/0x70 fs/super.c:1292
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2ac0d9d897
RSP: 002b:00007ffc7eaca848 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f2ac0e31ef0 RCX: 00007f2ac0d9d897
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc7eaca900
RBP: 00007ffc7eaca900 R08: 00007ffc7eacb900 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffc7eacb9f0
R13: 00007f2ac0e31ef0 R14: 0000000000049488 R15: 00007ffc7eaccac0
INFO: task syz.4.648:9292 blocked for more than 145 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.648 state:D stack:21920 pid:9292 tgid:9292 ppid:5838 task_flags:0x400640 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5340 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153
__flush_work+0xa17/0xc50 kernel/workqueue.c:4331
xfs_file_buffered_write+0x27d/0x8c0 fs/xfs/xfs_file.c:1036
__kernel_write_iter+0x41e/0x880 fs/read_write.c:621
dump_emit_page fs/coredump.c:1299 [inline]
dump_user_range+0xb89/0x12d0 fs/coredump.c:1373
elf_core_dump+0x34c2/0x3ad0 fs/binfmt_elf.c:2111
coredump_write+0x1219/0x1950 fs/coredump.c:1050
do_coredump fs/coredump.c:1127 [inline]
vfs_coredump+0x36a9/0x4280 fs/coredump.c:1201
get_signal+0x1107/0x1330 kernel/signal.c:3019
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop kernel/entry/common.c:98 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x176/0x620 kernel/entry/common.c:219
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f2ac0d9c631
RSP: 002b:0000000000000030 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f2ac1015fa0 RCX: 00007f2ac0d9c629
RDX: 0000000000000000 RSI: 0000000000000030 RDI: 0000000000000600
RBP: 00007f2ac0e32b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f2ac1016038 R14: 00007f2ac1015fa0 R15: 00007ffc7eacc6c8
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/1:1/42:
#0: ffff8880685d6d48 ((wq_completion)xfs-sync/loop4){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254
#1: ffffc90000b27c40 ((work_completion)(&mp->m_flush_inodes_work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255
#2: ffff888065fd20e0 (&type->s_umount_key#58){++++}-{4:4}, at: xfs_flush_inodes_worker+0x45/0x80 fs/xfs/xfs_super.c:666
#3: ffff888026b3c820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:398 [inline]
#3: ffff888026b3c820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2923
2 locks held by kworker/u8:3/49:
#0: ffff88801e396948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254
#1: ffffc90000b97c40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255
3 locks held by kworker/0:2/802:
#0: ffff88801b06b548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254
#1: ffffc90003e07c40 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255
#2: ffffffff8fee9088 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182
2 locks held by getty/5588:
#0: ffff888032d5e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5838:
#0: ffff8880254c20e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880254c20e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880254c20e0 (&type->s_umount_key#54){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffff888065fd20e0 (&type->s_umount_key#58){++++}-{4:4}, at: ovl_sync_fs+0x127/0x160 fs/overlayfs/super.c:261
8 locks held by kworker/0:3/5868:
#0: ffff88801b06b548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254
#1: ffffc90004047c40 ((rfkill_op_work).work){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255
#2: ffffffff8fee9088 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_epo+0x4c/0x180 net/rfkill/core.c:462
#3: ffff88802b4b8ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x28/0xc0 net/bluetooth/hci_core.c:500
#4: ffff88802b4b80c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346
#5: ffffffff8fd5cbe8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#5: ffffffff8fd5cbe8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644
#6: ffff88807b9d4af8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 net/bluetooth/l2cap_core.c:1755
#7: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#7: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
4 locks held by kworker/u8:10/7034:
2 locks held by syz.4.648/9292:
#0: ffff888065fd2420 (sb_writers#22){.+.+}-{0:0}, at: do_coredump fs/coredump.c:1127 [inline]
#0: ffff888065fd2420 (sb_writers#22){.+.+}-{0:0}, at: vfs_coredump+0x36a9/0x4280 fs/coredump.c:1201
#1: ffff88806c2a2130 (&sb->s_type->i_mutex_key#34){++++}-{4:4}, at: xfs_ilock+0xee/0x3b0 fs/xfs/xfs_inode.c:149
2 locks held by syz-executor/9599:
#0: ffff888065fba0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888065fba0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888065fba0e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz.6.829/10240:
#0: ffff8880254c20e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880254c20e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.9.902/10726:
#0: ffff8880254c20e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880254c20e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
2 locks held by dhcpcd-run-hook/11422:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7034 Comm: kworker/u8:10 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: writeback wb_workfn (flush-7:4)
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 ae 90 83 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 5f bf ed fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 4a a6 70 06 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900032b58f0 EFLAGS: 00000002
RAX: 1ffffffff34bb300 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffffff9a5d9b90 R08: ffff888142688237 R09: 1ffff110284d1046
R10: dffffc0000000000 R11: ffffffff85421250 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9a5d9900 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125555000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559642a8c048 CR3: 000000007ecfe000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x1a1/0x2f0 drivers/tty/serial/8250/8250_port.c:1961
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
serial8250_console_write+0x1348/0x1ba0 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3183 [inline]
console_flush_one_record kernel/printk/printk.c:3269 [inline]
console_flush_all+0x718/0xb20 kernel/printk/printk.c:3343
__console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3413
vprintk_emit+0x485/0x560 kernel/printk/printk.c:2479
_printk+0xdd/0x130 kernel/printk/printk.c:2504
print_hex_dump+0x1d2/0x2b0 lib/hexdump.c:286
xfs_hex_dump+0x3d/0x50 fs/xfs/xfs_message.c:110
xfs_buf_verifier_error+0x1cc/0x2a0 fs/xfs/xfs_error.c:330
xfs_allocbt_read_verify+0x5f/0xe0 fs/xfs/libxfs/xfs_alloc_btree.c:-1
__xfs_buf_ioend+0x332/0x710 fs/xfs/xfs_buf.c:1174
xfs_buf_iowait+0x167/0x4d0 fs/xfs/xfs_buf.c:1381
_xfs_buf_read fs/xfs/xfs_buf.c:643 [inline]
xfs_buf_read_map+0x324/0xa80 fs/xfs/xfs_buf.c:709
xfs_trans_read_buf_map+0x1db/0x950 fs/xfs/xfs_trans_buf.c:304
xfs_trans_read_buf fs/xfs/xfs_trans.h:212 [inline]
xfs_btree_read_buf_block+0x2b0/0x490 fs/xfs/libxfs/xfs_btree.c:1402
xfs_btree_lookup_get_block+0x297/0x510 fs/xfs/libxfs/xfs_btree.c:1907
xfs_btree_lookup+0x45a/0x1350 fs/xfs/libxfs/xfs_btree.c:2018
xfs_alloc_lookup fs/xfs/libxfs/xfs_alloc.c:166 [inline]
xfs_alloc_lookup_ge fs/xfs/libxfs/xfs_alloc.c:198 [inline]
xfs_alloc_cur_setup fs/xfs/libxfs/xfs_alloc.c:966 [inline]
xfs_alloc_ag_vextent_near+0x46b/0x12a0 fs/xfs/libxfs/xfs_alloc.c:1705
xfs_alloc_vextent_iterate_ags+0x66f/0x9a0 fs/xfs/libxfs/xfs_alloc.c:3764
xfs_alloc_vextent_start_ag+0x378/0x880 fs/xfs/libxfs/xfs_alloc.c:3839
xfs_bmap_btalloc_best_length fs/xfs/libxfs/xfs_bmap.c:3619 [inline]
xfs_bmap_btalloc fs/xfs/libxfs/xfs_bmap.c:3663 [inline]
xfs_bmapi_allocate+0x17c1/0x2da0 fs/xfs/libxfs/xfs_bmap.c:3938
xfs_bmapi_convert_one_delalloc fs/xfs/libxfs/xfs_bmap.c:4447 [inline]
xfs_bmapi_convert_delalloc+0x87a/0x1520 fs/xfs/libxfs/xfs_bmap.c:4503
xfs_map_blocks fs/xfs/xfs_aops.c:449 [inline]
xfs_writeback_range+0x69e/0xff0 fs/xfs/xfs_aops.c:493
iomap_writeback_range fs/iomap/buffered-io.c:1768 [inline]
iomap_writeback_folio+0x15f2/0x2770 fs/iomap/buffered-io.c:1887
iomap_writepages+0x167/0x2e0 fs/iomap/buffered-io.c:1950
xfs_vm_writepages+0x2fa/0x3e0 fs/xfs/xfs_aops.c:705
do_writepages+0x32e/0x550 mm/page-writeback.c:2554
__writeback_single_inode+0x133/0x11a0 fs/fs-writeback.c:1751
writeback_sb_inodes+0x992/0x1a20 fs/fs-writeback.c:2043
wb_writeback+0x456/0xb70 fs/fs-writeback.c:2228
wb_do_writeback fs/fs-writeback.c:2375 [inline]
wb_workfn+0x414/0xf50 fs/fs-writeback.c:2415
process_one_work+0x949/0x1650 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0xb46/0x1140 kernel/workqueue.c:3443
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245