INFO: task syz.0.2069:14662 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2069 state:D stack:26184 pid:14662 tgid:14661 ppid:9073 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760 bdev_open+0xa2/0xe40 block/bdev.c:945 bdev_file_open_by_dev block/bdev.c:1059 [inline] bdev_file_open_by_dev+0x182/0x210 block/bdev.c:1034 setup_bdev_super+0x39b/0x730 fs/super.c:1610 get_tree_bdev_flags+0x363/0x620 fs/super.c:1690 vfs_get_tree+0x8b/0x340 fs/super.c:1815 do_new_mount fs/namespace.c:3808 [inline] path_mount+0x1513/0x2000 fs/namespace.c:4123 do_mount fs/namespace.c:4136 [inline] __do_sys_mount fs/namespace.c:4347 [inline] __se_sys_mount fs/namespace.c:4324 [inline] __x64_sys_mount+0x28d/0x310 fs/namespace.c:4324 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: 0033:0x7f0d9a98ebe9 RSP: 002b:00007f0d9b800038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f0d9abb5fa0 RCX: 00007f0d9a98ebe9 RDX: 0000200000000080 RSI: 0000200000000040 RDI: 0000200000000000 RBP: 00007f0d9aa11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000001a0c000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0d9abb6038 R14: 00007f0d9abb5fa0 R15: 00007ffd32891818 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c1220 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 2 locks held by getty/5611: #0: ffff888035de20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 3 locks held by kworker/u8:15/10054: 1 lock held by udevd/14052: #0: ffff888026c02358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945 2 locks held by syz.0.2069/14662: #0: ffff888032a2a0e0 (&type->s_umount_key#94/1){+.+.}-{4:4}, at: alloc_super+0x235/0xbd0 fs/super.c:345 #1: ffff888026c02358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xa2/0xe40 block/bdev.c:945 2 locks held by syz.4.2540/16482: #0: ffffffff9036c7d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:566 #1: ffffffff8e5cc7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 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: 203 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:_static_cpu_has arch/x86/include/asm/cpufeature.h:101 [inline] RIP: 0010:addr_has_metadata mm/kasan/kasan.h:334 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:177 [inline] RIP: 0010:kasan_check_range+0x32/0x1b0 mm/kasan/generic.c:189 Code: 84 64 01 00 00 48 89 f8 41 54 44 0f b6 c2 48 01 f0 55 53 0f 82 d7 00 00 00 eb 0f cc cc cc 48 b8 00 00 00 00 00 00 00 ff eb 0a <48> b8 00 00 00 00 00 80 ff ff 48 39 c7 0f 82 b3 00 00 00 4c 8d 54 RSP: 0018:ffffc900030679f8 EFLAGS: 00000286 RAX: ffffc90003067a44 RBX: ffff8880606b8f00 RCX: ffffffff819810fc RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90003067a40 RBP: 1ffff9200060cf44 R08: 0000000000000001 R09: ffffed100c0d71e0 R10: ffff8880606b8f03 R11: 0000000000000000 R12: ffff8880606b8f08 R13: ffff8880606b8f10 R14: ffff88814374cd80 R15: ffff888031a601e0 FS: 0000000000000000(0000) GS:ffff8881247bb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffff CR3: 0000000062031000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1301 [inline] queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] do_raw_spin_lock+0x12c/0x2b0 kernel/locking/spinlock_debug.c:116 spin_lock_bh include/linux/spinlock.h:356 [inline] batadv_nc_purge_paths+0xd9/0x3a0 net/batman-adv/network-coding.c:442 batadv_nc_worker+0x921/0x1030 net/batman-adv/network-coding.c:720 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245