INFO: task syz-executor:5842 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:23840 pid:5842 tgid:5842 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
netfs_wait_for_outstanding_io include/linux/netfs.h:552 [inline]
v9fs_evict_inode+0x26f/0x300 fs/9p/vfs_inode.c:348
evict+0x3e3/0x920 fs/inode.c:810
iput_final fs/inode.c:1897 [inline]
iput fs/inode.c:1923 [inline]
iput+0x521/0x880 fs/inode.c:1909
dentry_unlink_inode+0x29c/0x480 fs/dcache.c:466
__dentry_kill+0x1d0/0x600 fs/dcache.c:669
dput.part.0+0x4b1/0x9b0 fs/dcache.c:911
dput fs/dcache.c:901 [inline]
do_one_tree fs/dcache.c:1607 [inline]
shrink_dcache_for_umount+0x159/0x3e0 fs/dcache.c:1621
generic_shutdown_super+0x6c/0x390 fs/super.c:621
kill_anon_super+0x3a/0x60 fs/super.c:1282
v9fs_kill_super+0x3d/0xa0 fs/9p/vfs_super.c:195
deactivate_locked_super+0xc1/0x1a0 fs/super.c:474
deactivate_super fs/super.c:507 [inline]
deactivate_super+0xde/0x100 fs/super.c:503
cleanup_mnt+0x225/0x450 fs/namespace.c:1375
task_work_run+0x14d/0x240 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb04358ff17
RSP: 002b:00007ffdce6684b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fb043611c05 RCX: 00007fb04358ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdce668570
RBP: 00007ffdce668570 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdce669600
R13: 00007fb043611c05 R14: 00000000000d5c15 R15: 00007ffdce669640
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/5600:
#0: ffff8880324630a0 (&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+0x41b/0x14f0 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5842:
#0: ffff88801b9ac0e0 (&type->s_umount_key#85){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88801b9ac0e0 (&type->s_umount_key#85){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88801b9ac0e0 (&type->s_umount_key#85){+.+.}-{4:4}, at: deactivate_super fs/super.c:506 [inline]
#0: ffff88801b9ac0e0 (&type->s_umount_key#85){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503
2 locks held by syz-executor/14167:
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3433
#1: ffffffff8e5cc7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
3 locks held by kworker/1:1/14225:
#0: ffff88801b878d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc9000427fd10 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffffffff8e5cc7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz-executor/14462:
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3433
2 locks held by kworker/u8:13/15919:
#0: ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:644 [inline]
#0: ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:629
#1: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:220 [inline]
#1: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: __schedule+0x1861/0x5de0 kernel/sched/core.c:6955
1 lock held by syz.8.3165/18263:
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3433
1 lock held by syz.3.3167/18284:
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3433
1 lock held by syz.2.3166/18269:
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90382ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3433
=============================================
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 07/12/2025
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:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf0e/0x1260 kernel/hung_task.c:491
kthread+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 4c 62 02 c3 cc cc cc cc 0f 1f 00 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 d3 52 16 00 fb f4 4c 09 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2
RAX: 00000000047ee831 RBX: 0000000000000001 RCX: ffffffff8b93bc29
RDX: 0000000000000000 RSI: ffffffff8de4fd28 RDI: ffffffff8c162900
RBP: ffffed1003c56488 R08: 0000000000000001 R09: ffffed10170a6655
R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801e2b2440 R14: ffffffff90ab4390 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881247bb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000404030 CR3: 000000000e380000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428
start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x148