INFO: task syz.4.5791:28063 blocked in I/O wait for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.5791 state:D stack:24616 pid:28063 tgid:28061 ppid:23461 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
io_schedule+0x7f/0xd0 kernel/sched/core.c:8154
folio_wait_bit_common+0x836/0xbc0 mm/filemap.c:1323
__folio_lock mm/filemap.c:1704 [inline]
folio_lock include/linux/pagemap.h:1157 [inline]
__filemap_get_folio_mpol+0x140/0x1000 mm/filemap.c:1960
__filemap_get_folio include/linux/pagemap.h:761 [inline]
truncate_inode_pages_range+0x46d/0xd80 mm/truncate.c:413
ext4_truncate_failed_write fs/ext4/truncate.h:21 [inline]
ext4_write_end+0x734/0x9e0 fs/ext4/inode.c:1495
generic_perform_write+0x612/0x8f0 mm/filemap.c:4379
ext4_buffered_write_iter+0xcb/0x370 fs/ext4/file.c:316
ext4_file_write_iter+0x947/0x1c70 fs/ext4/file.c:-1
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x612/0xba0 fs/read_write.c:687
ksys_write+0x150/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f569f79de59
RSP: 002b:00007f56a063b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f569fa25fa0 RCX: 00007f569f79de59
RDX: 000000000000fea7 RSI: 0000200000000180 RDI: 0000000000000005
RBP: 00007f569f833e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f569fa26038 R14: 00007f569fa25fa0 R15: 00007fff21fb8298
INFO: task syz.4.5791:28093 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.4.5791 state:D stack:23496 pid:28093 tgid:28061 ppid:23461 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
rwsem_down_read_slowpath+0x6ba/0x920 kernel/locking/rwsem.c:1114
__down_read_common kernel/locking/rwsem.c:1291 [inline]
__down_read kernel/locking/rwsem.c:1304 [inline]
down_read+0x9c/0x330 kernel/locking/rwsem.c:1576
filemap_invalidate_lock_shared include/linux/fs.h:1089 [inline]
page_cache_ra_order+0x3eb/0xee0 mm/readahead.c:517
page_cache_sync_readahead include/linux/pagemap.h:1395 [inline]
collapse_file mm/khugepaged.c:2335 [inline]
collapse_scan_file+0x1ab9/0x5210 mm/khugepaged.c:2773
collapse_single_pmd+0x4de/0x3da0 mm/khugepaged.c:2808
madvise_collapse+0x2cf/0x790 mm/khugepaged.c:3234
madvise_vma_behavior+0x11ac/0x42e0 mm/madvise.c:1364
madvise_walk_vmas+0x576/0xb00 mm/madvise.c:1713
madvise_do_behavior+0x385/0x540 mm/madvise.c:1908
do_madvise+0x327/0x3a0 mm/madvise.c:2006
__do_sys_madvise mm/madvise.c:2015 [inline]
__se_sys_madvise mm/madvise.c:2013 [inline]
__x64_sys_madvise+0xa6/0xc0 mm/madvise.c:2013
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f569f79de59
RSP: 002b:00007f56a061a028 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007f569fa26090 RCX: 00007f569f79de59
RDX: 0000000000000019 RSI: 0000000000600000 RDI: 0000200000000000
RBP: 00007f569f833e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f569fa26128 R14: 00007f569fa26090 R15: 00007fff21fb8298
Showing all locks held in the system:
2 locks held by ksoftirqd/1/23:
1 lock held by khungtaskd/31:
#0: ffffffff8e959c20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e959c20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e959c20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:4/75:
#0: ffff88801cf54140 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88801cf54140 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc9000246fc40 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc9000246fc40 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffffffff8fdecec0 (rtnl_mutex){+.+.}-{4:4}, at: cfg80211_dfs_channels_update_work+0xd9/0x640 net/wireless/mlme.c:1048
3 locks held by kworker/u8:6/182:
#0: ffff88801ae8c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88801ae8c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90002f6fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90002f6fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffffffff8fdecec0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
1 lock held by dhcpcd/5279:
#0: ffffffff8fdecec0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8fdecec0 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x2fb/0x1c50 net/ipv4/devinet.c:1120
2 locks held by getty/5374:
#0: ffff8880363270a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
6 locks held by kworker/u8:34/6725:
#0: ffff88801be9e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88801be9e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90003b7fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90003b7fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffffffff8fdde328 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:673
#3: ffffffff8fdecec0 (rtnl_mutex){+.+.}-{4:4}, at: ieee80211_unregister_hw+0x55/0x2c0 net/mac80211/main.c:1710
#4: ffff888037ad07a0 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6884 [inline]
#4: ffff888037ad07a0 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x132/0x6a0 net/mac80211/iface.c:2461
#5: ffffffff8e95ff28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#5: ffffffff8e95ff28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
5 locks held by kworker/1:2/17249:
#0: ffff8880226c6540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff8880226c6540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90004dc7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90004dc7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffff88802be441d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88802be441d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4d30 drivers/usb/core/hub.c:5899
#3: ffff888029817568 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline]
#3: ffff888029817568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline]
#3: ffff888029817568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#3: ffff888029817568 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#3: ffff888029817568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x20a1/0x4d30 drivers/usb/core/hub.c:5953
#4: ffff88802bd90660 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline]
#4: ffff88802bd90660 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#4: ffff88802bd90660 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#4: ffff88802bd90660 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x20c9/0x4d30 drivers/usb/core/hub.c:5953
3 locks held by kworker/1:4/23914:
#0: ffff88813fe4f140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88813fe4f140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90005547c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90005547c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffff888033066250 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1fd/0x3b0 drivers/net/netdevsim/fib.c:1490
3 locks held by kworker/u8:9/27639:
#0: ffff88803573f140 ((wq_completion)udp_tunnel_nic){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88803573f140 ((wq_completion)udp_tunnel_nic){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90012ce7c40 ((work_completion)(&utn->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90012ce7c40 ((work_completion)(&utn->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffffffff8fdecec0 (rtnl_mutex){+.+.}-{4:4}, at: udp_tunnel_nic_device_sync_work+0x29/0xa20 net/ipv4/udp_tunnel_nic.c:736
4 locks held by syz.4.5791/28063:
#0: ffff888077b9db30 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
#1: ffff888033d48450 (sb_writers#4){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2728 [inline]
#1: ffff888033d48450 (sb_writers#4){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffff888052712900 (&sb->s_type->i_mutex_key#11){++++}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
#2: ffff888052712900 (&sb->s_type->i_mutex_key#11){++++}-{4:4}, at: ext4_buffered_write_iter+0x9c/0x370 fs/ext4/file.c:311
#3: ffff888052712a98 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_invalidate_lock include/linux/fs.h:1079 [inline]
#3: ffff888052712a98 (mapping.invalidate_lock#2){++++}-{4:4}, at: ext4_truncate_failed_write fs/ext4/truncate.h:20 [inline]
#3: ffff888052712a98 (mapping.invalidate_lock#2){++++}-{4:4}, at: ext4_write_end+0x713/0x9e0 fs/ext4/inode.c:1495
1 lock held by syz.4.5791/28093:
#0: ffff888052712a98 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1089 [inline]
#0: ffff888052712a98 (mapping.invalidate_lock#2){++++}-{4:4}, at: page_cache_ra_order+0x3eb/0xee0 mm/readahead.c:517
1 lock held by syz-executor/30120:
#0: ffffffff8fdecec0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8fdecec0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8fdecec0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158
1 lock held by syz.7.6451/30464:
#0: ffff88807d4d8140 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#0: ffff88807d4d8140 (&dev->mutex){....}-{4:4}, at: nfc_unregister_rfkill+0x63/0x280 net/nfc/core.c:1166
4 locks held by syz.7.6451/30465:
#0: ffffffff8fe5d5a8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8fe5d3e0 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff8fe5d3e0 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff8fe5d3e0 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
#2: ffff88807d4d8140 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88807d4d8140 (&dev->mutex){....}-{4:4}, at: nfc_dev_up+0x3c/0x350 net/nfc/core.c:95
#3: ffff8880528f8348 (&ndev->req_lock){+.+.}-{4:4}, at: nci_open_device net/nfc/nci/core.c:478 [inline]
#3: ffff8880528f8348 (&ndev->req_lock){+.+.}-{4:4}, at: nci_dev_up+0xa3/0xdc0 net/nfc/nci/core.c:643
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 27639 Comm: kworker/u8:9 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: udp_tunnel_nic udp_tunnel_nic_device_sync_work
RIP: 0010:to_desc kernel/printk/printk_ringbuffer.c:362 [inline]
RIP: 0010:desc_read+0xb1/0x3f0 kernel/printk/printk_ringbuffer.c:455
Code: 75 f5 1f 00 48 c7 c0 ff ff ff ff 89 e9 48 d3 e0 48 f7 d0 4c 21 f0 48 6b d8 58 49 83 c7 08 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 <74> 08 4c 89 ff e8 d5 79 8d 00 48 01 5c 24 18 49 8b 1f 48 c7 c0 ff
RSP: 0018:ffffc90012ce6e60 EFLAGS: 00000246
RAX: 1ffffffff1d0df9d RBX: 000000000006bb90 RCX: 000000000000000d
RDX: 0000000000000000 RSI: 000000000000000d RDI: 0000000000000040
RBP: 000000000000000d R08: 0000000000000000 R09: 1ffffffff1d0a25e
R10: dffffc0000000000 R11: fffffbfff1d0a25f R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000001396 R15: ffffffff8e86fce8
FS: 0000000000000000(0000) GS:ffff888125220000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9cb03ed2f8 CR3: 000000000e746000 CR4: 0000000000350ef0
Call Trace:
desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1934 [inline]
prb_read kernel/printk/printk_ringbuffer.c:1982 [inline]
_prb_read_valid+0x286/0xa50 kernel/printk/printk_ringbuffer.c:2173
prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2245
printk_get_next_message+0x18b/0x880 kernel/printk/printk.c:3052
console_emit_next_record kernel/printk/printk.c:3137 [inline]
console_flush_one_record kernel/printk/printk.c:3269 [inline]
console_flush_all+0x4e3/0xaf0 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
dev_vprintk_emit+0x338/0x400 drivers/base/core.c:4996
dev_printk_emit+0xee/0x140 drivers/base/core.c:5007
__netdev_printk+0x3e1/0x480 net/core/dev.c:12958
netdev_info+0x11e/0x180 net/core/dev.c:13013
nsim_udp_tunnel_set_port+0x226/0x380 drivers/net/netdevsim/udp_tunnels.c:31
udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:-1 [inline]
udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:249 [inline]
__udp_tunnel_nic_device_sync+0xb62/0x1560 net/ipv4/udp_tunnel_nic.c:292
udp_tunnel_nic_device_sync_work+0x83/0xa20 net/ipv4/udp_tunnel_nic.c:740
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245