INFO: task syz.1.3127:16204 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.1.3127 state:D stack:23816 pid:16204 tgid:16203 ppid:11430 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5282 [inline] __schedule+0x14ed/0x5040 kernel/sched/core.c:6894 __schedule_loop kernel/sched/core.c:6976 [inline] schedule+0x165/0x360 kernel/sched/core.c:6991 io_schedule+0x80/0xd0 kernel/sched/core.c:7820 folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1170 [inline] migrate_folio_unmap mm/migrate.c:1249 [inline] migrate_pages_batch+0x14cd/0x35e0 mm/migrate.c:1890 migrate_pages_sync mm/migrate.c:2034 [inline] migrate_pages+0x2006/0x28e0 mm/migrate.c:2116 compact_zone+0x25ba/0x4760 mm/compaction.c:2647 compact_node mm/compaction.c:2916 [inline] compact_nodes mm/compaction.c:2938 [inline] sysctl_compaction_handler+0x3a1/0x7b0 mm/compaction.c:2989 proc_sys_call_handler+0x4cb/0x700 fs/proc/proc_sysctl.c:600 iter_file_splice_write+0x972/0x10b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x101/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5a8/0xcc0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1230 do_sendfile+0x4da/0x7e0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1425 [inline] __se_sys_sendfile64+0xd9/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f008978f749 RSP: 002b:00007f008a6f8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f00899e5fa0 RCX: 00007f008978f749 RDX: 00002000000000c0 RSI: 0000000000000008 RDI: 0000000000000009 RBP: 00007f0089813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f00899e6038 R14: 00007f00899e5fa0 R15: 00007fff658136b8 Showing all locks held in the system: 1 lock held by rcu_exp_gp_kthr/18: #0: ffff8880b873ab98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:644 1 lock held by khungtaskd/31: #0: ffffffff8e33efa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e33efa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e33efa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:2/34: 2 locks held by getty/5576: #0: ffff888034ceb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 7 locks held by kworker/0:4/5828: #0: ffff888021698548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254 #1: ffffc9000417fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255 #2: ffff8881437cf198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff8881437cf198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899 #3: ffff888056bf9198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] ffff888056bf9198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x990 drivers/usb/core/hub.c:2336 #4: ffff8880319e3160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff8880319e3160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1104 [inline] #4: ffff8880319e3160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800 drivers/base/dd.c:1302 #5: ffffffff8f1b3d88 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:254 [inline] #5: ffffffff8f1b3d88 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x328/0x640 drivers/input/input.c:2187 #6: ffffffff8e3445b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #6: ffffffff8e3445b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2b1/0x6e0 kernel/rcu/tree_exp.h:961 1 lock held by udevd/11429: #0: ffff888141781358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962 4 locks held by udevd/11437: #0: ffff88805a187668 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20 fs/seq_file.c:183 #1: ffff888024b28088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff88807dc4b3c8 (kn->active#30){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff88807dc4b3c8 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff888056bf9198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline] #3: ffff888056bf9198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 1 lock held by syz.1.3127/16204: #0: ffff888059a90420 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 ============================================= 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 10/25/2025 Call Trace: 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:375 [inline] watchdog+0xe88/0xee0 kernel/hung_task.c:588 kthread+0x389/0x480 kernel/kthread.c:467 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11437 Comm: udevd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:lock_is_held_type+0x40/0x150 kernel/locking/lockdep.c:5933 Code: 09 5d 04 00 0f 84 e5 00 00 00 65 8b 05 69 71 5f 07 85 c0 0f 85 d6 00 00 00 65 4c 8b 2c 25 08 50 c6 92 41 83 bd 04 0b 00 00 00 <0f> 85 bf 00 00 00 89 f5 49 89 fe 9c 41 5c fa 48 c7 c7 b9 84 ac 8d RSP: 0018:ffffc90000007ba8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 0000000080010004 RDX: 00000000d7fe226f RSI: 00000000ffffffff RDI: ffffffff8e33efa0 RBP: 0000000000000000 R08: ffffffff81951509 R09: ffffffff8e33efa0 R10: dffffc0000000000 R11: ffffffff81951200 R12: ffffffff8dcd3dd0 R13: ffff888027820000 R14: dffffc0000000000 R15: ffffffff8dcd3dd0 FS: 00007fb34b18f880(0000) GS:ffff8881259bb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31815ff8 CR3: 00000000761d0000 CR4: 00000000003526f0 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] rcu_read_lock_any_held+0x33/0x90 kernel/rcu/update.c:386 test_idle_cores kernel/sched/fair.c:7515 [inline] select_idle_sibling kernel/sched/fair.c:7870 [inline] select_task_rq_fair+0x1f0b/0x3570 kernel/sched/fair.c:8578 select_task_rq kernel/sched/core.c:3512 [inline] try_to_wake_up+0x4d8/0x12b0 kernel/sched/core.c:4221 hrtimer_wakeup+0x4e/0x60 kernel/time/hrtimer.c:2013 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x51c/0xc30 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:rcu_lockdep_current_cpu_online+0x37/0x120 kernel/rcu/tree.c:4044 Code: 0a 1f 11 b0 01 f7 c1 00 00 f0 00 0f 85 d5 00 00 00 83 3d 3f b8 1c 0e 00 0f 84 c8 00 00 00 65 ff 05 de 09 1f 11 e8 19 f6 bf 09 <89> c3 83 f8 08 0f 83 c7 00 00 00 49 be 00 00 00 00 00 fc ff df 48 RSP: 0018:ffffc9000bb6f738 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8be259c0 RDI: ffffffff8be25980 RBP: ffff888025be5d60 R08: ffffc900003bbc17 R09: 1ffff92000077782 R10: dffffc0000000000 R11: fffff52000077783 R12: dffffc0000000000 R13: ffffffff82406996 R14: 00000000377826b4 R15: ffff888025be5c28 rcu_read_lock_held_common kernel/rcu/update.c:113 [inline] rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349 hlist_bl_first_rcu include/linux/rculist_bl.h:24 [inline] __d_lookup+0x170/0x780 fs/dcache.c:2437 lookup_fast+0x84/0x5b0 fs/namei.c:1822 walk_component fs/namei.c:2223 [inline] link_path_walk+0x720/0x18d0 fs/namei.c:2595 path_lookupat+0xe4/0x8c0 fs/namei.c:2751 filename_lookup+0x212/0x570 fs/namei.c:2781 vfs_statx+0xf8/0x550 fs/stat.c:353 vfs_fstatat+0x118/0x170 fs/stat.c:375 __do_sys_newfstatat fs/stat.c:542 [inline] __se_sys_newfstatat fs/stat.c:536 [inline] __x64_sys_newfstatat+0x116/0x190 fs/stat.c:536 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb34ab11b0a Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7 RSP: 002b:00007ffc232e19b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 00007ffc232e1e50 RCX: 00007fb34ab11b0a RDX: 00007ffc232e19c0 RSI: 00007ffc232e1e50 RDI: 00000000ffffff9c RBP: 000055b4748f9910 R08: 0000000000000000 R09: 0000000000000020 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc232e1a50 R13: 00007ffc232e2285 R14: 000055b46f7f9ca4 R15: 000055b46f7f9bcc