INFO: task syz.3.7473:554 blocked for more than 143 seconds. Not tainted 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.7473 state:D stack:26832 pid:554 tgid:552 ppid:5829 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 bit_wait+0x15/0xe0 kernel/sched/wait_bit.c:237 __wait_on_bit+0x62/0x180 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0xda/0x110 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:77 [inline] netfs_unbuffered_write_iter_locked+0xaa1/0xd30 fs/netfs/direct_write.c:108 netfs_unbuffered_write_iter+0x413/0x6d0 fs/netfs/direct_write.c:195 v9fs_file_write_iter+0xbf/0x100 fs/9p/vfs_file.c:404 new_sync_write fs/read_write.c:586 [inline] vfs_write+0x5ae/0x1150 fs/read_write.c:679 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f650c38d169 RSP: 002b:00007f650d128038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f650c5a5fa0 RCX: 00007f650c38d169 RDX: 0000000000007fec RSI: 0000400000000540 RDI: 0000000000000007 RBP: 00007f650c40e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f650c5a5fa0 R15: 00007ffcc47c3538 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 2 locks held by klogd/5184: #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline] #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591 #1: ffff8880b8628a88 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2c1/0x8e0 kernel/sched/psi.c:987 2 locks held by getty/5583: #0: ffff888032a7d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 2 locks held by kworker/u8:5/15277: #0: ffff88801b081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213 #1: ffffc90003517d18 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3214 3 locks held by syz.3.7473/554: #0: ffff888038bf4638 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x267/0x390 fs/file.c:1192 #1: ffff88802230e420 (sb_writers#19){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #2: ffff888055241498 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: netfs_start_io_direct+0x116/0x260 fs/netfs/locking.c:188 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 23137 Comm: kworker/u8:13 Not tainted 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:rcu_is_watching+0x5/0xc0 kernel/rcu/tree.c:712 Code: c0 54 03 e9 51 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <53> 65 ff 05 8b 42 64 7e e8 1e f6 b7 09 48 c7 c3 28 7c 03 00 83 f8 RSP: 0018:ffffc900101779c0 EFLAGS: 00000047 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8b584a28 RDX: fffffbfff20c4d03 RSI: 0000000000000008 RDI: ffffffff90626810 RBP: ffffc90010177b68 R08: 0000000000000000 R09: fffffbfff20c4d02 R10: ffffffff90626817 R11: ffff8880b8628abc R12: ffff88802971c880 R13: ffff888056d2d410 R14: 0000000000000000 R15: ffff8880b863ec00 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005562e2a60680 CR3: 000000000df80000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x1edd/0x5890 kernel/sched/core.c:6762 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 toggle_allocation_gate mm/kfence/core.c:852 [inline] toggle_allocation_gate+0x1db/0x260 mm/kfence/core.c:842 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244