INFO: task syz.1.2163:13906 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.2163 state:D stack:28776 pid:13906 tgid:13905 ppid:5594 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xccc/0x1bd0 kernel/locking/mutex.c:821
write_ports+0xa5/0xcc0 fs/nfsd/nfsctl.c:860
nfsctl_transaction_write+0x106/0x1a0 fs/nfsd/nfsctl.c:112
vfs_write+0x2aa/0x1050 fs/read_write.c:685
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc72b39e0d9
RSP: 002b:00007fc72c28c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fc72b625fa0 RCX: 00007fc72b39e0d9
RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000004
RBP: 00007fc72b435024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc72b626038 R14: 00007fc72b625fa0 R15: 00007ffc1746f5b8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8ebe8200 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8ebe8200 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8ebe8200 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/48:
#0: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:675 [inline]
#0: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:659
#1: ffff8880b8524568 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:218 [inline]
#1: ffff8880b8524568 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2e8e/0x6730 kernel/sched/core.c:7228
#2: ffffffff8fbf2ec0 (deferred_probe_mutex){+.+.}-{4:4}, at: deferred_probe_work_func+0x21/0x2c0 drivers/base/dd.c:98
#3: ffff8880b8426298 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x124/0x1d0 kernel/time/timer.c:1004
2 locks held by getty/5358:
#0: ffff8880376b10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5595:
#0: ffff88807beca0d8 (&type->s_umount_key#88){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88807beca0d8 (&type->s_umount_key#88){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88807beca0d8 (&type->s_umount_key#88){+.+.}-{4:4}, at: deactivate_super fs/super.c:509 [inline]
#0: ffff88807beca0d8 (&type->s_umount_key#88){+.+.}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:506
#1: ffffffff8f0724c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:576
3 locks held by syz.0.2156/13884:
#0: ffff8880799bbcf0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259
#1: ffff8880282ea450 (sb_writers#23){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739
#2: ffffffff8f0724c0 (nfsd_mutex){+.+.}-{4:4}, at: write_ports+0xa5/0xcc0 fs/nfsd/nfsctl.c:860
3 locks held by syz.1.2163/13906:
#0: ffff8880792b75f0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259
#1: ffff88802c4e8450 (sb_writers#23){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739
#2: ffffffff8f0724c0 (nfsd_mutex){+.+.}-{4:4}, at: write_ports+0xa5/0xcc0 fs/nfsd/nfsctl.c:860
3 locks held by syz.3.2195/14012:
#0: ffff88807905e7f0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259
#1: ffff88807e0ae450 (sb_writers#23){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739
#2: ffffffff8f0724c0 (nfsd_mutex){+.+.}-{4:4}, at: write_ports+0xa5/0xcc0 fs/nfsd/nfsctl.c:860
3 locks held by kworker/0:8/14061:
#0: ffff88801bc0b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc9000de67d08 (key_gc_work){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffffffff8ebf3ca8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
2 locks held by syz-executor/14195:
#0: ffff88807b0de0d8 (&type->s_umount_key#88){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88807b0de0d8 (&type->s_umount_key#88){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88807b0de0d8 (&type->s_umount_key#88){+.+.}-{4:4}, at: deactivate_super fs/super.c:509 [inline]
#0: ffff88807b0de0d8 (&type->s_umount_key#88){+.+.}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:506
#1: ffffffff8f0724c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:576
3 locks held by syz.2.2390/14949:
#0: ffff88807a913eb0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259
#1: ffff888051ed8450 (sb_writers#23){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739
#2: ffffffff8f0724c0 (nfsd_mutex){+.+.}-{4:4}, at: write_ports+0xa5/0xcc0 fs/nfsd/nfsctl.c:860
1 lock held by syz.5.2591/15721:
#0: ffffffff8ebf3ca8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
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:122
nmi_trigger_cpumask_backtrace+0x21c/0x2a0 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+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 15721 Comm: syz.5.2591 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:record_times+0xe1/0x240 kernel/sched/psi.c:783
Code: c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 2a 01 00 00 44 01 63 1c 40 f6 c5 08 0f 85 d4 00 00 00 <40> f6 c5 10 74 38 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 24 48 89
RSP: 0018:ffffc9000475ee90 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffe8ffffd91e80 RCX: 0000000000000001
RDX: 1ffffd1ffffb23d2 RSI: 000000c80ded79cd RDI: ffffe8ffffd91e90
RBP: 0000000000000180 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000f6762
R13: 0000000000002463 R14: 0000000000000001 R15: ffff888026213000
FS: 0000000000000000(0000) GS:ffff888123eec000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffbf98effe0 CR3: 0000000077623000 CR4: 00000000003526f0
Call Trace:
psi_account_irqtime+0x62c/0xc70 kernel/sched/psi.c:1039
__schedule+0x6c0/0x6730 kernel/sched/core.c:7227
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7556
irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline]
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x205/0xa00 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x70 kernel/kcov.c:217
Code: 58 12 a9 00 01 ff 00 74 1b f6 c4 01 74 07 a9 00 00 ff 00 74 05 c3 cc cc cc cc 8b 82 24 17 00 00 85 c0 74 f1 8b 82 f8 16 00 00 <83> f8 02 75 e6 48 8b 8a 00 17 00 00 8b 92 fc 16 00 00 48 8b 01 48
RSP: 0018:ffffc9000475f170 EFLAGS: 00000246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff82859833
RDX: ffff888083b04a80 RSI: ffffffff8285983d RDI: ffff888083b04a80
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 000000000698029b R11: 0000000000000000 R12: ffff88801f8a80c0
R13: 000000000698029b R14: 0000000000000001 R15: ffff88801f8a80c8
__update_page_owner_free_handle.isra.0+0x16d/0x4b0 mm/page_owner.c:288
__reset_page_owner+0x93/0x190 mm/page_owner.c:321
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
free_unref_folios+0xa44/0x1710 mm/page_alloc.c:3011
folios_put_refs+0x585/0xaa0 mm/swap.c:1057
folio_batch_release include/linux/folio_batch.h:101 [inline]
shmem_undo_range+0x5e5/0x1570 mm/shmem.c:1159
shmem_truncate_range mm/shmem.c:1287 [inline]
shmem_evict_inode+0x3a5/0xbe0 mm/shmem.c:1417
evict+0x3c2/0xad0 fs/inode.c:825
iput_final fs/inode.c:2019 [inline]
iput.part.0+0x989/0x1050 fs/inode.c:2068
iput+0x35/0x40 fs/inode.c:2034
dentry_unlink_inode+0x284/0x470 fs/dcache.c:479
dentry_kill+0x25d/0xc20 fs/dcache.c:826
finish_dput fs/dcache.c:1001 [inline]
dput.part.0+0xd7/0x240 fs/dcache.c:1042
dput+0x1f/0x30 fs/dcache.c:1037
__fput+0x519/0xb50 fs/file_table.c:520
task_work_run+0x150/0x240 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x951/0x2ae0 kernel/exit.c:1009
do_group_exit+0xd5/0x2a0 kernel/exit.c:1152
get_signal+0x1ec7/0x21e0 kernel/signal.c:3046
arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop kernel/entry/common.c:101 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline]
irqentry_exit+0x402/0xa00 kernel/entry/common.c:165
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f73dbf9e0d9
Code: Unable to access opcode bytes at 0x7f73dbf9e0af.
RSP: 002b:fffffffffffffc70 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 00007f73dc225fa0 RCX: 00007f73dbf9e0d9
RDX: 0000000000000000 RSI: fffffffffffffc70 RDI: 0000000001022000
RBP: 00007f73dc035024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f73dc226038 R14: 00007f73dc225fa0 R15: 00007ffec1519d58