INFO: task syz.2.6251:30211 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.6251 state:D stack:25752 pid:30211 tgid:30208 ppid:29712 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xfe6/0x5fa0 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:6964
io_schedule+0x8a/0xf0 kernel/sched/core.c:7791
folio_wait_bit_common+0x414/0xa70 mm/filemap.c:1323
folio_lock include/linux/pagemap.h:1170 [inline]
migrate_folio_unmap mm/migrate.c:1249 [inline]
migrate_pages_batch+0x1b85/0x4530 mm/migrate.c:1890
migrate_pages_sync+0x4db/0x880 mm/migrate.c:2034
migrate_pages+0x1a5b/0x2810 mm/migrate.c:2116
compact_zone+0x240c/0x4320 mm/compaction.c:2647
compact_node+0x17f/0x2c0 mm/compaction.c:2916
compact_nodes mm/compaction.c:2938 [inline]
sysctl_compaction_handler mm/compaction.c:2989 [inline]
sysctl_compaction_handler+0x141/0x210 mm/compaction.c:2976
proc_sys_call_handler+0x47f/0x5a0 fs/proc/proc_sysctl.c:600
iter_file_splice_write+0x82b/0x10a0 fs/splice.c:738
do_splice_from fs/splice.c:938 [inline]
direct_splice_actor+0x192/0x6c0 fs/splice.c:1161
splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105
do_splice_direct_actor fs/splice.c:1204 [inline]
do_splice_direct+0x174/0x240 fs/splice.c:1230
do_sendfile+0xadc/0xe20 fs/read_write.c:1370
__do_sys_sendfile64 fs/read_write.c:1425 [inline]
__se_sys_sendfile64 fs/read_write.c:1417 [inline]
__x64_sys_sendfile64+0x154/0x220 fs/read_write.c:1417
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f615919aeb9
RSP: 002b:00007f61573d5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f6159416180 RCX: 00007f615919aeb9
RDX: 00002000000000c0 RSI: 0000000000000008 RDI: 0000000000000009
RBP: 00007f6159208c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6159416218 R14: 00007f6159416180 R15: 00007ffc1f638238
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:4/66:
1 lock held by klogd/5167:
#0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline]
#0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632
2 locks held by getty/5570:
#0: ffff8880326ea0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
3 locks held by kworker/u8:13/18835:
1 lock held by udevd/23029:
#0: ffff8880269c3358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:962
1 lock held by syz.2.6251/30211:
#0: ffff888058344420 (sb_writers#3){.+.+}-{0:0}, at: splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105
=============================================
NMI backtrace for cpu 0
CPU: 0 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 01/24/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 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+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xcc3/0xfe0 kernel/hung_task.c:515
kthread+0x3b3/0x730 kernel/kthread.c:463
ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 18835 Comm: kworker/u8:13 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:update_rq_clock_task kernel/sched/core.c:783 [inline]
RIP: 0010:update_rq_clock+0x409/0xd30 kernel/sched/core.c:854
Code: d5 20 1f ef 8d 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 c1 e9 03 80 3c 11 00 0f 85 c9 06 00 00 48 8d bb e0 0c 00 00 48 8b 00 <48> ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 11 00 0f
RSP: 0018:ffffc900040ff940 EFLAGS: 00000046
RAX: 000000172d524b00 RBX: ffff8880b853ac80 RCX: 1ffff110170a48b6
RDX: dffffc0000000000 RSI: 1ffffffff1bde3e5 RDI: ffff8880b853b960
RBP: ffff8880b853b7b8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff90b781d4
R13: ffff8880b853b868 R14: ffff8880b853b7b0 R15: 000000000057925b
FS: 0000000000000000(0000) GS:ffff8881246d9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b52bd99660 CR3: 000000000e392000 CR4: 00000000003526f0
Call Trace:
__schedule+0x3e2/0x5fa0 kernel/sched/core.c:6777
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:6964
toggle_allocation_gate mm/kfence/core.c:896 [inline]
toggle_allocation_gate+0x218/0x2d0 mm/kfence/core.c:886
process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x5da/0xe40 kernel/workqueue.c:3421
kthread+0x3b3/0x730 kernel/kthread.c:463
ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246