INFO: task syz-executor:5766 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:21608 pid:5766 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 io_schedule+0x80/0xd0 kernel/sched/core.c:9023 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329 __filemap_get_folio+0xbc/0xbb0 mm/filemap.c:1910 truncate_inode_pages_range+0x46b/0xfb0 mm/truncate.c:401 evict+0x4dd/0x8d0 fs/inode.c:707 dispose_list fs/inode.c:738 [inline] evict_inodes+0x606/0x6a0 fs/inode.c:792 generic_shutdown_super+0x97/0x2b0 fs/super.c:672 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x43b/0x4d0 fs/namespace.c:1259 task_work_run+0x1d4/0x260 kernel/task_work.c:245 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fc417d9d897 RSP: 002b:00007fffa28670e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fc417e31ef0 RCX: 00007fc417d9d897 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffa28671a0 RBP: 00007fffa28671a0 R08: 00007fffa28681a0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffa2868230 R13: 00007fc417e31ef0 R14: 00000000001abd4a R15: 00007fffa2868270 Showing all locks held in the system: 1 lock held by khungtaskd/28: #0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by kworker/u4:8/3450: 2 locks held by getty/5521: #0: ffff88803132a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000328b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217 1 lock held by syz-executor/5765: 1 lock held by syz-executor/5766: #0: ffff88802ed520e0 (&type->s_umount_key#69){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802ed520e0 (&type->s_umount_key#69){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88802ed520e0 (&type->s_umount_key#69){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 1 lock held by udevd/6068: #0: ffff8880b8e3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf3d/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 23208 Comm: kworker/u4:0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: bat_events batadv_nc_worker RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3781 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3837 [inline] RIP: 0010:__lock_acquire+0x1359/0x7d40 kernel/locking/lockdep.c:5137 Code: e8 03 25 f8 03 00 00 48 8d b8 00 f5 1b 91 be 08 00 00 00 e8 69 05 77 00 49 b8 00 00 00 00 00 fc ff df 48 0f a3 1d e7 bb b3 0f <72> 25 48 c7 c0 80 64 2c 97 48 c1 e8 03 42 0f b6 04 00 84 c0 0f 85 RSP: 0018:ffffc9000b78f700 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 00000000000006d5 RCX: ffffffff81683907 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff911bf5d8 RBP: ffffc9000b78f948 R08: dffffc0000000000 R09: 1ffffffff2237ebb R10: dffffc0000000000 R11: fffffbfff2237ebc R12: 97a9abc294ccf596 R13: ffff888031743c00 R14: 0000000094ccf596 R15: ffff888031744750 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f27491ea4b8 CR3: 00000000773a8000 CR4: 00000000003506e0 Call Trace: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] batadv_nc_purge_paths+0xe7/0x3a0 net/batman-adv/network-coding.c:442 batadv_nc_worker+0x369/0x610 net/batman-adv/network-coding.c:722 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 vkms_vblank_simulate: vblank timer overrun