INFO: task syz.1.653:7981 blocked in I/O wait for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.653 state:D stack:24584 pid:7981 tgid:7980 ppid:5582 task_flags:0x400140 flags:0x00080002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5520 [inline]
__schedule+0x16d9/0x5700 kernel/sched/core.c:7270
__schedule_loop kernel/sched/core.c:7347 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7362
io_schedule+0x80/0xe0 kernel/sched/core.c:8190
folio_wait_bit_common+0x83c/0xbc0 mm/filemap.c:1329
folio_lock include/linux/pagemap.h:1186 [inline]
migrate_folio_unmap mm/migrate.c:1261 [inline]
migrate_pages_batch+0x1c7f/0x43b0 mm/migrate.c:1919
migrate_pages_sync mm/migrate.c:2063 [inline]
migrate_pages+0x1f90/0x2900 mm/migrate.c:2145
compact_zone+0x3434/0x4c00 mm/compaction.c:2698
compact_node mm/compaction.c:2945 [inline]
compact_nodes mm/compaction.c:2967 [inline]
sysctl_compaction_handler+0x3f3/0x880 mm/compaction.c:3018
proc_sys_call_handler+0x4c7/0x830 fs/proc/proc_sysctl.c:600
iter_file_splice_write+0xa36/0x1240 fs/splice.c:736
do_splice_from fs/splice.c:936 [inline]
direct_splice_actor+0x104/0x160 fs/splice.c:1159
splice_direct_to_actor+0x586/0xcc0 fs/splice.c:1103
do_splice_direct_actor fs/splice.c:1202 [inline]
do_splice_direct+0x19b/0x2a0 fs/splice.c:1228
do_sendfile+0x540/0x7e0 fs/read_write.c:1371
__do_sys_sendfile64 fs/read_write.c:1426 [inline]
__se_sys_sendfile64+0xdf/0x1a0 fs/read_write.c:1418
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f53eebbe0d9
RSP: 002b:00007f53ece16028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f53eee45fa0 RCX: 00007f53eebbe0d9
RDX: 00002000000000c0 RSI: 0000000000000003 RDI: 0000000000000004
RBP: 00007f53eec55024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f53eee46038 R14: 00007f53eee45fa0 R15: 00007ffcd37a8368
</TASK>
Showing all locks held in the system:
locks held by kworker/u8:1/13: 5, last CPU#0:
#0: ffff888032ce6138 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffff888032ce6138 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffff888032ce6138 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#0: ffff888032ce6138 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#1: ffffc90000127c40 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffc90000127c40 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#1: ffffc90000127c40 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#1: ffffc90000127c40 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#2: ffffffff8e059280 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3d/0x420 kernel/softirq.c:186
#3: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3d/0x420 kernel/softirq.c:186
#4: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: spin_lock_bh include/linux/spinlock_rt.h:90 [inline]
#4: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: batadv_tt_local_purge+0x13e/0x380 net/batman-adv/translation-table.c:1400
locks held by khungtaskd/37: 1, last CPU#1:
#0: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6793
locks held by kworker/u8:8/1166: 3, on CPU#0:
#0: ffff88813ff64138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffff88813ff64138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffff88813ff64138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#0: ffff88813ff64138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#1: ffffc90006397c40 ((linkwatch_work).work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffc90006397c40 ((linkwatch_work).work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#1: ffffc90006397c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#1: ffffc90006397c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#2: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
locks held by kworker/u8:9/1173: 6, last CPU#1:
#0: ffff88801aea8938 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffff88801aea8938 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffff88801aea8938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#0: ffff88801aea8938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#1: ffffc90006347c40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffc90006347c40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#1: ffffc90006347c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#1: ffffc90006347c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#2: ffffffff8f5b8bc0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:677
#3: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
#3: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x28e/0x8d0 net/core/net_namespace.c:249
#4: ffff888038ea4e80 (&net->mpls.platform_mutex){+.+.}-{4:4}, at: mpls_dev_notify+0x82/0xd30 net/mpls/af_mpls.c:1648
#5: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#5: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e2/0x400 kernel/locking/spinlock_rt.c:57
locks held by dhcpcd/5244: 1, on CPU#1:
#0: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#0: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x2fb/0x1c50 net/ipv4/devinet.c:1120
locks held by getty/5337: 2, on CPU#1:
#0: ffff8880360200a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
locks held by udevd/5691: 1, on CPU#0:
#0: ffff8880279c04c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd00 block/bdev.c:990
locks held by kworker/1:7/5722: 3, on CPU#1:
#0: ffff88813ff23938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffff88813ff23938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffff88813ff23938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#0: ffff88813ff23938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#1: ffffc9000521fc40 (netdev_work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffc9000521fc40 (netdev_work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#1: ffffc9000521fc40 (netdev_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#1: ffffc9000521fc40 (netdev_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#2: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: netdev_work_proc+0x72/0x7f0 net/core/netdev_work.c:132
locks held by kworker/1:8/6399: 3, on CPU#1:
#0: ffff88813ff23938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffff88813ff23938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffff88813ff23938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#0: ffff88813ff23938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#1: ffffc900080bfc40 (deferred_process_work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffc900080bfc40 (deferred_process_work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#1: ffffc900080bfc40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline]
#1: ffffc900080bfc40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470
#2: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
locks held by syz.1.653/7981: 1, on CPU#0:
#0: ffff888032ffe510 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1158
locks held by syz-executor/9244: 1, on CPU#0:
#0: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
#0: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4214
locks held by syz.5.1059/9346: 1, on CPU#0:
#0: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: wext_ioctl_dispatch+0xa2/0x410 net/wireless/wext-core.c:1010
locks held by syz.3.1064/9368: 1, last CPU#0:
#0: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
#0: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495
locks held by syz.2.1067/9385: 1, on CPU#0:
#0: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x3dd/0x1e70 drivers/net/tun.c:3229
locks held by syz.2.1067/9388: 1, on CPU#0:
#0: ffffffff8f5c7438 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x3dd/0x1e70 drivers/net/tun.c:3229
locks held by syz.0.1072/9408: 3, last CPU#0:
#0: ffff888011c933f0 (&u->iolock){+.+.}-{4:4}, at: __unix_dgram_recvmsg+0x1e3/0xd70 net/unix/af_unix.c:2587
#1: ffff888011c92d98 (rlock-AF_UNIX){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#1: ffff888011c92d98 (rlock-AF_UNIX){+.+.}-{3:3}, at: __skb_try_recv_datagram+0x89/0x1b0 net/core/datagram.c:264
#2: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#2: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#2: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#2: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e2/0x400 kernel/locking/spinlock_rt.c:57
locks held by syz.3.1073/9410: 3, last CPU#1:
#0: ffff88803fc50430 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline]
#0: ffff88803fc50430 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1a4/0x9f0 mm/mmap.c:1299
#1: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#1: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290
#2: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#2: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#2: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#2: ffffffff8e1c3740 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e2/0x400 kernel/locking/spinlock_rt.c:57
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [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+0x38b/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
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13 Comm: kworker/u8:1 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:preempt_count_sub+0x72/0x180 kernel/sched/core.c:6036
Code: c0 0f 94 c1 81 ff ff 00 00 00 0f 92 c2 45 84 f6 0f 94 c0 84 ca 75 02 31 c0 84 c0 75 57 f7 df 48 63 c7 65 48 01 05 4e 93 0e 11 <5b> 41 5e 5d e9 55 29 c0 09 cc 90 e8 5e 32 31 03 85 c0 74 33 48 c7
RSP: 0018:ffffc900001279c0 EFLAGS: 00000097
RAX: ffffffffffffffff RBX: dffffc0000000000 RCX: ffffffff99ac0501
RDX: 0000000000000001 RSI: ffffffff8db2f7dc RDI: 00000000ffffffff
RBP: 0000000000000001 R08: ffffffff8fb16e37 R09: 1ffffffff1f62dc6
R10: dffffc0000000000 R11: fffffbfff1f62dc7 R12: ffff88801cabdd00
R13: 1ffff11003957d1f R14: 8000000000000001 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125bf4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc1dd2bed40 CR3: 000000006d2d2000 CR4: 00000000003526f0
Call Trace:
<TASK>
class_preempt_destructor include/linux/preempt.h:500 [inline]
__migrate_enable include/linux/sched.h:2471 [inline]
migrate_enable include/linux/sched.h:2511 [inline]
__local_bh_enable+0x15b/0x2f0 kernel/softirq.c:273
__local_bh_enable_ip+0x19f/0x2b0 kernel/softirq.c:328
local_bh_enable include/linux/bottom_half.h:33 [inline]
spin_unlock_bh include/linux/spinlock_rt.h:122 [inline]
batadv_tt_global_purge net/batman-adv/translation-table.c:2390 [inline]
batadv_tt_purge+0x45a/0x9f0 net/batman-adv/translation-table.c:3754
process_one_work kernel/workqueue.c:3387 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
kthread+0x38b/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
</TASK>