INFO: task syz.3.2337:12402 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.3.2337 state:D stack:27112 pid:12402 tgid:12401 ppid:5849 task_flags:0x400140 flags:0x00080002 Call Trace: 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:4359 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: 0033:0x7f044f19c799 RSP: 002b:00007f0450125028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f044f415fa0 RCX: 00007f044f19c799 RDX: 0000200000004500 RSI: 00002000000000c0 RDI: 0000000000000000 RBP: 00007f044f232c99 R08: 0000200000000100 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f044f416038 R14: 00007f044f415fa0 R15: 00007fffeda07548 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/1:5/5899: #0: ffff88813fe03140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc90004877c40 (p9_poll_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 2 locks held by getty/9922: #0: ffff88803788a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000e35b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz.0.3458/15595: #0: ffffffff8eb637b8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 1 lock held by syz.7.3460/15601: #0: ffffffff8eb637b8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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: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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 1154 Comm: kworker/u8:8 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:bpf_net_ctx_clear include/linux/filter.h:808 [inline] RIP: 0010:net_rx_action+0xe29/0xf70 net/core/dev.c:7956 Code: 24 68 00 74 07 e8 07 f1 35 f8 eb 25 e8 00 f1 35 f8 48 8b 44 24 50 42 80 3c 20 00 4c 8b 74 24 40 74 08 4c 89 f7 e8 47 6b 9f f8 <49> c7 06 00 00 00 00 66 42 c7 44 23 1a f8 f8 66 42 c7 44 23 16 f8 RSP: 0018:ffffc90000007d40 EFLAGS: 00000246 RAX: 1ffff110052d0e7f RBX: 1ffff92000000fbc RCX: ffff888029685b80 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8880b843c840 RBP: ffffc90000007f40 R08: ffffffff905441f7 R09: 1ffffffff20a883e R10: dffffc0000000000 R11: fffffbfff20a883f R12: dffffc0000000000 R13: ffffc90000007e90 R14: ffff8880296873f8 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888124de2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000313030 CR3: 000000002d8e2000 CR4: 00000000003526f0 Call Trace: handle_softirqs+0x22a/0x870 kernel/softirq.c:626 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline] __dev_queue_xmit+0x1efe/0x3870 net/core/dev.c:4878 dev_queue_xmit include/linux/netdevice.h:3389 [inline] batadv_send_skb_packet+0x418/0x690 net/batman-adv/send.c:100 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:391 [inline] batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x631/0x7e0 net/batman-adv/bat_iv_ogm.c:1697 process_one_work+0x9ab/0x1780 kernel/workqueue.c:3289 process_scheduled_works kernel/workqueue.c:3380 [inline] worker_thread+0xba8/0x11e0 kernel/workqueue.c:3466 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