INFO: task syz.5.425:7990 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-10401-gdee264c16a63 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.425 state:D stack:26200 pid:7990 tgid:7979 ppid:7848 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 rwsem_down_read_slowpath+0x62f/0xb60 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0xef/0x480 kernel/locking/rwsem.c:1526 __super_lock fs/super.c:59 [inline] super_lock+0x31c/0x3f0 fs/super.c:121 __iterate_supers+0x1e0/0x330 fs/super.c:923 ksys_sync+0x89/0x150 fs/sync.c:102 __do_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f205bb8e969 RSP: 002b:00007f205c9c3038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f205bdb6080 RCX: 00007f205bb8e969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f205bdb6080 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f205bdb6080 R15: 00007fffbd1d7018 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 3 locks held by kworker/u8:3/49: #0: ffff8880b843bd18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] #0: ffff8880b843bd18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 #1: ffffc90000ba7d10 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff8880b8425ad8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x127/0x1d0 kernel/time/timer.c:1004 2 locks held by getty/5575: #0: ffff88814c5bc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5807: #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: deactivate_super fs/super.c:506 [inline] #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503 2 locks held by kworker/u8:60/6462: #0: ffff8880b843bd18 (&rq->__lock){-.-.}-{2:2}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9001aeefd10 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 1 lock held by syz.5.425/7990: #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x31c/0x3f0 fs/super.c:121 1 lock held by syz.2.525/8248: #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x31c/0x3f0 fs/super.c:121 1 lock held by syz.2.525/8253: #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x31c/0x3f0 fs/super.c:121 1 lock held by syz.7.680/8886: #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880267180e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x31c/0x3f0 fs/super.c:121 7 locks held by kworker/0:1/9477: #0: ffff88802228d548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9001aabfd10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888144b90198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #2: ffff888144b90198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fa0 drivers/usb/core/hub.c:5859 #3: ffff88805c0e2198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #3: ffff88805c0e2198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2307 #4: ffff888025b96160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #4: ffff888025b96160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff888025b96160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1292 #5: ffffffff903446a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #5: ffffffff903446a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x146/0x360 net/core/dev.c:2143 #6: ffffffff8e5cfd38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x280/0x3c0 kernel/rcu/tree_exp.h:304 1 lock held by syz.8.834/9521: #0: ffffffff8e5cfc00 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3782 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-10401-gdee264c16a63 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 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: 6462 Comm: kworker/u8:60 Not tainted 6.15.0-syzkaller-10401-gdee264c16a63 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:__local_bh_enable_ip+0x7b/0x120 kernel/softirq.c:400 Code: 85 c0 74 0b 65 8b 05 4c 5f 4e 12 85 c0 74 57 9c 58 fa f6 c4 02 75 60 65 8b 05 e1 1d 4e 12 25 00 ff 00 00 3d 00 02 00 00 74 54 <83> eb 01 f7 db 65 01 1d c9 1d 4e 12 65 8b 05 c2 1d 4e 12 a9 00 ff RSP: 0018:ffffc9001aeefa98 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000201 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8dde190c RDI: ffffffff8c1532c0 RBP: ffffffff8b499244 R08: 0000000000000001 R09: fffffbfff214f10a R10: ffffffff90a78857 R11: 0000000000000001 R12: ffffffff8b4995f0 R13: ffff88805c5fd540 R14: ffff88804a2a8d80 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812476e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c401fda CR3: 0000000078ad3000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x1d4/0x3a0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x921/0x1030 net/batman-adv/network-coding.c:720 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245