INFO: task syz.2.184:6760 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.184 state:D stack:20536 pid:6760 tgid:6759 ppid:5872 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
inode_lock include/linux/fs.h:870 [inline]
vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
do_setxattr fs/xattr.c:636 [inline]
filename_setxattr+0x274/0x600 fs/xattr.c:665
path_setxattrat+0x364/0x3a0 fs/xattr.c:713
__do_sys_setxattr fs/xattr.c:747 [inline]
__se_sys_setxattr fs/xattr.c:743 [inline]
__x64_sys_setxattr+0xbc/0xe0 fs/xattr.c:743
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f060118eec9
RSP: 002b:00007f0601fbb038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f06013e5fa0 RCX: 00007f060118eec9
RDX: 0000200000000340 RSI: 0000200000000140 RDI: 0000200000000100
RBP: 00007f0601211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000700 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f06013e6038 R14: 00007f06013e5fa0 R15: 00007ffd4f893a58
INFO: task syz.2.184:6781 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.184 state:D stack:22056 pid:6781 tgid:6759 ppid:5872 task_flags:0x440040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
___down_common kernel/locking/semaphore.c:268 [inline]
__down_common+0x319/0x6a0 kernel/locking/semaphore.c:293
down+0x80/0xd0 kernel/locking/semaphore.c:100
xfs_buf_lock+0x15d/0x4d0 fs/xfs/xfs_buf.c:996
xfs_buf_find_lock+0x42/0x4c0 fs/xfs/xfs_buf.c:422
xfs_buf_lookup fs/xfs/xfs_buf.c:475 [inline]
xfs_buf_get_map+0x10b7/0x1860 fs/xfs/xfs_buf.c:597
xfs_buf_read_map+0x82/0xa50 fs/xfs/xfs_buf.c:702
xfs_trans_read_buf_map+0x1d7/0x8e0 fs/xfs/xfs_trans_buf.c:304
xfs_trans_read_buf fs/xfs/xfs_trans.h:210 [inline]
xfs_read_agf+0x281/0x5c0 fs/xfs/libxfs/xfs_alloc.c:3376
xfs_alloc_read_agf+0x17c/0xb70 fs/xfs/libxfs/xfs_alloc.c:3411
xfs_alloc_fix_freelist+0x60a/0x1300 fs/xfs/libxfs/xfs_alloc.c:2875
xfs_alloc_vextent_prepare_ag+0xdb/0x610 fs/xfs/libxfs/xfs_alloc.c:3566
xfs_alloc_vextent_iterate_ags+0x140/0x940 fs/xfs/libxfs/xfs_alloc.c:3750
xfs_alloc_vextent_start_ag+0x388/0x850 fs/xfs/libxfs/xfs_alloc.c:3839
xfs_bmap_btalloc_best_length fs/xfs/libxfs/xfs_bmap.c:3627 [inline]
xfs_bmap_btalloc fs/xfs/libxfs/xfs_bmap.c:3672 [inline]
xfs_bmapi_allocate+0x188e/0x2e00 fs/xfs/libxfs/xfs_bmap.c:3947
xfs_bmapi_convert_one_delalloc fs/xfs/libxfs/xfs_bmap.c:4456 [inline]
xfs_bmapi_convert_delalloc+0x7e2/0x1430 fs/xfs/libxfs/xfs_bmap.c:4512
xfs_map_blocks fs/xfs/xfs_aops.c:445 [inline]
xfs_writeback_range+0x674/0xf70 fs/xfs/xfs_aops.c:489
iomap_writeback_range fs/iomap/buffered-io.c:1585 [inline]
iomap_writeback_folio+0xe75/0x1c80 fs/iomap/buffered-io.c:1710
iomap_writepages+0x162/0x2d0 fs/iomap/buffered-io.c:1762
xfs_vm_writepages+0x296/0x310 fs/xfs/xfs_aops.c:701
do_writepages+0x32e/0x550 mm/page-writeback.c:2634
filemap_fdatawrite_wbc mm/filemap.c:386 [inline]
__filemap_fdatawrite_range mm/filemap.c:419 [inline]
file_write_and_wait_range+0x23e/0x340 mm/filemap.c:794
xfs_file_fsync+0x1a3/0xa30 fs/xfs/xfs_file.c:140
generic_write_sync include/linux/fs.h:3043 [inline]
xfs_file_buffered_write+0x723/0x8a0 fs/xfs/xfs_file.c:1019
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x5c9/0xb30 fs/read_write.c:686
ksys_write+0x145/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f060118eec9
RSP: 002b:00007f0601f79038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f06013e6180 RCX: 00007f060118eec9
RDX: 000000000208e24b RSI: 0000200000001400 RDI: 0000000000000004
RBP: 00007f0601211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f06013e6218 R14: 00007f06013e6180 R15: 00007ffd4f893a58
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13a120 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13a120 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13a120 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by dhcpcd/5522:
#0: ffff88805e03e6d8 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2406
#1: ffffffff8f53a188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f53a188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6814
2 locks held by getty/5618:
#0: ffff88814d3b70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:4/5953:
#0: ffff88801a478d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801a478d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000442fbc0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000442fbc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8e13fbb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8e13fbb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957
2 locks held by syz.2.184/6760:
#0: ffff888032aea428 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88806dcb9a70 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:870 [inline]
#1: ffff88806dcb9a70 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
4 locks held by syz.2.184/6780:
#0: ffff888032aea428 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88806dcb9a70 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:870 [inline]
#1: ffff88806dcb9a70 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
#2: ffff888032aea618 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc+0xd7/0x980 fs/xfs/xfs_trans.c:256
#3: ffff88806dcb9858 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1081
4 locks held by syz.2.184/6781:
#0: ffff88805df477b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1232
#1: ffff888032aea428 (sb_writers#21){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3108 [inline]
#1: ffff888032aea428 (sb_writers#21){.+.+}-{0:0}, at: vfs_write+0x211/0xb30 fs/read_write.c:682
#2: ffff888032aea618 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc+0xd7/0x980 fs/xfs/xfs_trans.c:256
#3: ffff888069b79858 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_bmapi_convert_one_delalloc fs/xfs/libxfs/xfs_bmap.c:4391 [inline]
#3: ffff888069b79858 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_bmapi_convert_delalloc+0x32c/0x1430 fs/xfs/libxfs/xfs_bmap.c:4512
4 locks held by kworker/u8:12/7155:
#0: ffff88801de80948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801de80948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc90004327bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc90004327bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffff888032aea0e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff888069b79858 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_map_blocks fs/xfs/xfs_aops.c:370 [inline]
#3: ffff888069b79858 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_writeback_range+0x33d/0xf70 fs/xfs/xfs_aops.c:489
4 locks held by syz-executor/7350:
#0: ffff88804fa44dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline]
#0: ffff88804fa44dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x510 net/bluetooth/hci_core.c:2715
#1: ffff88804fa440b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5289
#2: ffffffff8f69efe8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2115 [inline]
#2: ffffffff8f69efe8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2599
#3: ffff8880510fbb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762
3 locks held by kworker/u8:25/7829:
#0: ffff88801a481148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801a481148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000419fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000419fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8f53a188 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
2 locks held by syz.6.437/8452:
#0: ffffffff8f53a188 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8f53a188 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
#1: ffffffff8e13fbb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e13fbb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
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: 5965 Comm: kworker/1:6 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:407
Code: f7 6f fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 cc 74 d3 fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 92 7d c0 fb cc 44 89 f9 80 e1 07 38 c1
RSP: 0018:ffffc900044bee50 EFLAGS: 00000002
RAX: 0000000000000033 RBX: 0000000000000033 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 000000000001b0d1 RDI: 000000000001b0d2
RBP: 00000000000003f8 R08: ffff888024500237 R09: 1ffff110048a0046
R10: dffffc0000000000 R11: ffffffff854fc2f0 R12: dffffc0000000000
R13: ffffffff99b038cd R14: ffffffff99df8460 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125d12000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005643a4a08468 CR3: 0000000030448000 CR4: 0000000000350ef0
Call Trace:
serial_port_out include/linux/serial_core.h:798 [inline]
serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3246 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
serial8250_console_write+0x1410/0x1ba0 drivers/tty/serial/8250/8250_port.c:3396
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x728/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4914
dev_printk_emit+0xe0/0x130 drivers/base/core.c:4925
_dev_info+0x10a/0x160 drivers/base/core.c:4983
hub_port_init+0x5cf/0x2800 drivers/usb/core/hub.c:4995
hub_port_connect drivers/usb/core/hub.c:5495 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
port_event drivers/usb/core/hub.c:5870 [inline]
hub_event+0x2532/0x4a20 drivers/usb/core/hub.c:5952
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245