INFO: task syz.1.3546:20486 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.3546      state:D stack:24096 pid:20486 tgid:20478 ppid:12865  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0x1553/0x5240 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7008
 io_schedule+0x80/0xe0 kernel/sched/core.c:7835
 folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1323
 folio_lock include/linux/pagemap.h:1170 [inline]
 migrate_folio_unmap mm/migrate.c:1250 [inline]
 migrate_pages_batch+0x1864/0x4090 mm/migrate.c:1890
 migrate_pages_sync mm/migrate.c:2034 [inline]
 migrate_pages+0x20c5/0x2a50 mm/migrate.c:2116
 compact_zone+0x26ec/0x4890 mm/compaction.c:2647
 compact_node mm/compaction.c:2916 [inline]
 compact_nodes mm/compaction.c:2938 [inline]
 sysctl_compaction_handler+0x3f3/0x870 mm/compaction.c:2989
 proc_sys_call_handler+0x4c9/0x830 fs/proc/proc_sysctl.c:600
 iter_file_splice_write+0x9a6/0x10f0 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+0x545/0xc80 fs/splice.c:1103
 do_splice_direct_actor fs/splice.c:1202 [inline]
 do_splice_direct+0x19b/0x2a0 fs/splice.c:1228
 do_sendfile+0x547/0x7e0 fs/read_write.c:1372
 __do_sys_sendfile64 fs/read_write.c:1427 [inline]
 __se_sys_sendfile64+0xdf/0x1a0 fs/read_write.c:1419
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98c28cc799
RSP: 002b:00007f98c0adc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f98c2b46180 RCX: 00007f98c28cc799
RDX: 00002000000000c0 RSI: 0000000000000008 RDI: 0000000000000009
RBP: 00007f98c2962c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f98c2b46218 R14: 00007f98c2b46180 R15: 00007ffef19dd958
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/1:0H/32:
 #0: ffff88801f2b7538 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
 #0: ffff88801f2b7538 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
 #1: ffffc90000a6fc40 ((work_completion)(&q->timeout_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
 #1: ffffc90000a6fc40 ((work_completion)(&q->timeout_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
1 lock held by khungtaskd/37:
 #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5565:
 #0: ffff8880371670a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by udevd/19512:
 #0: ffff8880265594c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:961
1 lock held by udevd/19766:
 #0: ffff8880264f94c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:961
1 lock held by syz.1.3546/20486:
 #0: ffff8880355a2480 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1158

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 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:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 5e 5d 02 e9 13 c4 03 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 8c 26 00 fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc900001d7e20 EFLAGS: 00000246
RAX: 0000000001ec1321 RBX: ffffffff81996dba RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d560e78 RDI: ffffffff8ba66a00
RBP: ffffc900001d7f10 R08: ffff8880b8933f1b R09: 1ffff110171267e3
R10: dffffc0000000000 R11: ffffed10171267e4 R12: ffffffff8f6a3db0
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff1100395f000
FS:  0000000000000000(0000) GS:ffff88812643c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056408bccf168 CR3: 000000000dbba000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1ba/0x5d0 kernel/sched/idle.c:341
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:439
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147
 </TASK>