INFO: task syz-executor:5836 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21832 pid:5836 tgid:5836 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 netfs_wait_for_outstanding_io include/linux/netfs.h:552 [inline] v9fs_evict_inode+0x170/0x320 fs/9p/vfs_inode.c:348 evict+0x501/0x9c0 fs/inode.c:810 __dentry_kill+0x209/0x660 fs/dcache.c:669 dput+0x19f/0x2b0 fs/dcache.c:911 shrink_dcache_for_umount+0xa0/0x170 fs/dcache.c:1621 generic_shutdown_super+0x67/0x2c0 fs/super.c:621 kill_anon_super+0x3b/0x70 fs/super.c:1282 v9fs_kill_super+0x4c/0x90 fs/9p/vfs_super.c:195 deactivate_locked_super+0xb9/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1375 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/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+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2dfe3f01f7 RSP: 002b:00007ffecbba7b28 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f2dfe471d7d RCX: 00007f2dfe3f01f7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffecbba7be0 RBP: 00007ffecbba7be0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffecbba8c70 R13: 00007f2dfe471d7d R14: 00000000000bec8e R15: 00007ffecbba8cb0 Showing all locks held in the system: 9 locks held by ktimers/0/16: 1 lock held by khungtaskd/38: #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/0:2/994: #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000492fbc0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000492fbc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 3 locks held by kworker/u8:7/1121: 2 locks held by getty/5600: #0: ffff88823bf3a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e762e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5836: #0: ffff88805e05e0d0 (&type->s_umount_key#62){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88805e05e0d0 (&type->s_umount_key#62){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88805e05e0d0 (&type->s_umount_key#62){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 6 locks held by kworker/1:5/5921: 10 locks held by syz-executor/9606: 6 locks held by kworker/u8:20/10871: 1 lock held by syz.7.2182/13189: #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6952 2 locks held by syz.8.2183/13180: #0: ffff8880302b8938 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:870 [inline] #0: ffff8880302b8938 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:648 [inline] #0: ffff8880302b8938 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1439 #1: ffff88803c84a350 (sk_lock-AF_CAIF){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1669 [inline] #1: ffff88803c84a350 (sk_lock-AF_CAIF){+.+.}-{0:0}, at: caif_release+0x125/0x3c0 net/caif/caif_socket.c:914 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/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+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148 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: 13191 Comm: syz.2.2186 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0033:0x7fbc0b88ed66 Code: 89 fb 48 89 d0 49 8d 14 d2 49 39 50 28 0f 82 b5 03 00 00 c6 44 24 1e 01 45 31 ff 45 31 f6 44 0f b6 e6 85 c0 0f 84 9e 00 00 00 <44> 89 f9 49 8b 50 40 4c 89 f0 49 03 14 ca 80 3d 2d 90 37 00 00 49 RSP: 002b:00007ffd3b8c5780 EFLAGS: 00000297 RAX: 0000000000000001 RBX: 00007fbc0c735720 RCX: ffffffff81f627bb RDX: 00000000000007bc RSI: ffffffff81f627bb RDI: 0000000000000009 RBP: ffffffff81f627bb R08: 00007fbc0bc06038 R09: 00007fbc0bbf2000 R10: 00007fbc0b41f008 R11: 0000000000000009 R12: 0000000000000009 R13: 0000000000000000 R14: ffffffff81f62b39 R15: 000000000004be27 FS: 000055555bd0f500 GS: 0000000000000000