INFO: task syz-executor:8763 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:21832 pid:8763 tgid:8763 ppid:1 task_flags:0x400140 flags:0x00004006 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 __bch2_fs_stop+0x704/0x900 fs/bcachefs/super.c:696 generic_shutdown_super+0x132/0x2c0 fs/super.c:643 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2618 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1375 task_work_run+0x1d1/0x260 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: 0033:0x7fc1eb5601f7 RSP: 002b:00007ffc7fc4b138 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fc1eb5601f7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc7fc4b1f0 RBP: 00007ffc7fc4b1f0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc7fc4c280 R13: 00007fc1eb5e1d7d R14: 0000000000080f61 R15: 00007ffc7fc4c2c0 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: #0: ffff888030507938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888030507938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90000117bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90000117bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194 1 lock held by khungtaskd/38: #0: ffffffff8d9a8dc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8dc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8dc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 7 locks held by kworker/u8:6/996: 4 locks held by kworker/u8:9/1184: #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90004dcfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004dcfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecc69a0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: fib6_rules_net_exit_batch+0x20/0xc0 net/ipv6/fib6_rules.c:641 2 locks held by dhcpcd/5500: #0: ffff888030b76910 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90 net/netlink/af_netlink.c:2269 #1: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6814 2 locks held by getty/5593: #0: ffff88814dfb60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/8763: #0: ffff888029e060d0 (&type->s_umount_key#77){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff888029e060d0 (&type->s_umount_key#77){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff888029e060d0 (&type->s_umount_key#77){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 1 lock held by syz.6.713/11034: #0: ffff888029e060d0 (&type->s_umount_key#77){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff888029e060d0 (&type->s_umount_key#77){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz-executor/11067: 1 lock held by syz-executor/11126: #0: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 2 locks held by syz-executor/11289: #0: ffffffff8ecc69a0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566 #1: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline] #1: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x60 net/core/dev.c:11319 2 locks held by syz-executor/11357: #0: ffffffff8ecc69a0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566 #1: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline] #1: ffffffff8ecd38b8 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x60 net/core/dev.c:11319 1 lock held by syz-executor/11361: ============================================= NMI backtrace for cpu 0 CPU: 0 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+0x711/0x8a0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 996 Comm: kworker/u8:6 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:hlock_class kernel/locking/lockdep.c:229 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4879 [inline] RIP: 0010:__lock_acquire+0x4ff/0xd20 kernel/locking/lockdep.c:5187 Code: 44 89 e0 48 ff c3 48 63 8f 18 0b 00 00 49 83 c7 28 41 89 c4 48 39 cb 0f 8d d6 00 00 00 48 83 fb 31 0f 83 92 00 00 00 41 8b 07 <25> ff 1f 00 00 48 0f a3 05 74 ea 61 11 73 10 48 69 c0 c8 00 00 00 RSP: 0018:ffffc9000478f5b0 EFLAGS: 00000097 RAX: 00000000000409b5 RBX: 0000000000000000 RCX: 00000000ffffffff RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff888025a58000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8af97bd4 R10: dffffc0000000000 R11: fffffbfff1e3ac47 R12: ffffffffffffff05 R13: 0000000000000002 R14: ffff888025a58bc0 R15: ffff888025a58b40 FS: 0000000000000000(0000) GS:ffff8881269bc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056061b322828 CR3: 0000000032014000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 rtlock_slowlock kernel/locking/rtmutex.c:1894 [inline] rtlock_lock kernel/locking/spinlock_rt.c:43 [inline] __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline] rt_spin_lock+0x144/0x2c0 kernel/locking/spinlock_rt.c:57 spin_lock include/linux/spinlock_rt.h:44 [inline] __local_bh_disable_ip+0x264/0x400 kernel/softirq.c:168 local_bh_disable include/linux/bottom_half.h:20 [inline] spin_lock_bh include/linux/spinlock_rt.h:87 [inline] batadv_nc_purge_paths+0xf7/0x3f0 net/batman-adv/network-coding.c:442 batadv_nc_worker+0x87e/0xbc0 net/batman-adv/network-coding.c:720 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 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