INFO: task syz.4.3361:15576 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.3361      state:D stack:27232 pid:15576 tgid:15575 ppid:15435  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5352 [inline]
 __schedule+0x1665/0x5590 kernel/sched/core.c:6964
 __schedule_loop kernel/sched/core.c:7047 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7062
 schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153
 __flush_work+0xa17/0xc50 kernel/workqueue.c:4358
 p9_mux_poll_stop net/9p/trans_fd.c:140 [inline]
 p9_conn_destroy net/9p/trans_fd.c:804 [inline]
 p9_fd_close+0x245/0x430 net/9p/trans_fd.c:840
 p9_client_create+0x68d/0xc90 net/9p/client.c:937
 v9fs_session_init+0x46/0xdf0 fs/9p/v9fs.c:442
 v9fs_get_tree+0xbd/0xac0 fs/9p/vfs_super.c:97
 vfs_get_tree+0x92/0x2a0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3764 [inline]
 do_new_mount+0x341/0xd30 fs/namespace.c:3840
 do_mount fs/namespace.c:4173 [inline]
 __do_sys_mount fs/namespace.c:4372 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4349
 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: 0033:0x7f78f639c799
RSP: 002b:00007f78f728b028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f78f6615fa0 RCX: 00007f78f639c799
RDX: 0000200000004500 RSI: 00002000000000c0 RDI: 0000000000000000
RBP: 00007f78f6432c99 R08: 0000200000000100 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f78f6616038 R14: 00007f78f6615fa0 R15: 00007fff7b20b458
 </TASK>
INFO: task syz.0.3388:15646 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.3388      state:D stack:27936 pid:15646 tgid:15645 ppid:13976  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5352 [inline]
 __schedule+0x1665/0x5590 kernel/sched/core.c:6964
 __schedule_loop kernel/sched/core.c:7047 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7062
 schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153
 __flush_work+0xa17/0xc50 kernel/workqueue.c:4358
 p9_mux_poll_stop net/9p/trans_fd.c:140 [inline]
 p9_conn_destroy net/9p/trans_fd.c:804 [inline]
 p9_fd_close+0x245/0x430 net/9p/trans_fd.c:840
 p9_client_create+0x68d/0xc90 net/9p/client.c:937
 v9fs_session_init+0x46/0xdf0 fs/9p/v9fs.c:442
 v9fs_get_tree+0xbd/0xac0 fs/9p/vfs_super.c:97
 vfs_get_tree+0x92/0x2a0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3764 [inline]
 do_new_mount+0x341/0xd30 fs/namespace.c:3840
 do_mount fs/namespace.c:4173 [inline]
 __do_sys_mount fs/namespace.c:4372 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4349
 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: 0033:0x7f1fedb9c799
RSP: 002b:00007f1fee99d028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f1fede15fa0 RCX: 00007f1fedb9c799
RDX: 0000200000000080 RSI: 0000200000000300 RDI: 0000000000000000
RBP: 00007f1fedc32c99 R08: 0000200000000340 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1fede16038 R14: 00007f1fede15fa0 R15: 00007fff24bdc258
 </TASK>

Showing all locks held in the system:
no locks held by ksoftirqd/0/15.
1 lock held by khungtaskd/31:
 #0: ffffffff8eb5d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8eb5d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8eb5d6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5601:
 #0: ffff888033df00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by kworker/0:4/5889:
 #0: ffff88813fe03140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3260
 #1: ffffc90003e47c40 (p9_poll_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3261

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(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:162 [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:353 [inline]
 watchdog+0x1002/0x1060 kernel/hung_task.c:561
 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(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: ed 91 02 e9 d3 f1 02 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 13 a2 29 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:ffffffff8e807dc0 EFLAGS: 00000242
RAX: 0000000000f5dc01 RBX: ffffffff819bd46a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8e25d240 RDI: ffffffff8c4a8700
RBP: ffffffff8e807eb0 R08: ffff8880b84339db R09: 1ffff1101708673b
R10: dffffc0000000000 R11: ffffed101708673c R12: 0000000000000000
R13: 1ffffffff1d125d8 R14: 0000000000000000 R15: 1ffffffff1d125d8
FS:  0000000000000000(0000) GS:ffff888124de1000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f88051b6fd8 CR3: 0000000034500000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000005
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
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:199 [inline]
 do_idle+0x36a/0x5f0 kernel/sched/idle.c:352
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451
 rest_init+0x2de/0x300 init/main.c:762
 start_kernel+0x38f/0x3e0 init/main.c:1214
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x147
 </TASK>