INFO: task syz-executor:5769 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:21704 pid:5769 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: 0033:0x7fc8abd9bf17 RSP: 002b:00007ffe4a68bbb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fc8abe0471f RCX: 00007fc8abd9bf17 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe4a68bc70 RBP: 00007ffe4a68bc70 R08: 00007ffe4a68cc70 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe4a68cd00 R13: 00007fc8abe0471f R14: 00000000000178ca R15: 00007ffe4a68cd40 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by kworker/1:2/966: #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711 #1: ffffc900037f7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900037f7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711 3 locks held by kworker/u4:8/2953: 2 locks held by getty/5531: #0: ffff88802d0b50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217 1 lock held by syz-executor/5769: #0: ffff88807c4f40e0 (&type->s_umount_key#55){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807c4f40e0 (&type->s_umount_key#55){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807c4f40e0 (&type->s_umount_key#55){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 2 locks held by udevd/5777: 2 locks held by dhcpcd/9307: #0: ffff88805fdfd020 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff88805fdfd020 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff88805fdfd020 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1420 #1: ffffffff8d1379b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] #1: ffffffff8d1379b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x306/0x880 kernel/rcu/tree_exp.h:1004 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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: 59 Comm: kworker/u4:4 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:unwind_done arch/x86/include/asm/unwind.h:50 [inline] RIP: 0010:unwind_next_frame+0xa6/0x2970 arch/x86/kernel/unwind_orc.c:475 Code: 00 00 4c 89 e3 48 c1 eb 03 42 0f b6 04 2b 84 c0 0f 85 df 21 00 00 41 8b 2c 24 31 ff 89 ee e8 11 e0 4b 00 89 ac 24 8c 00 00 00 <85> ed 74 77 4c 89 74 24 60 48 89 5c 24 18 bf 01 00 00 00 e8 52 47 RSP: 0018:ffffc900015a7578 EFLAGS: 00000293 RAX: ffffffff813b36bf RBX: 1ffff920002b4ec9 RCX: 0000000000000000 RDX: ffff88801e680000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffc900015a7710 R09: 0000000000000001 R10: 0000000000000004 R11: 0000000000000000 R12: ffffc900015a7648 R13: dffffc0000000000 R14: ffffc900015a7680 R15: ffffffff81df161f FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055db42e46168 CR3: 000000007ad82000 CR4: 00000000003506e0 Call Trace: arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc_node_track_caller+0xb2/0x230 mm/slab_common.c:1027 kmalloc_reserve+0x116/0x240 net/core/skbuff.c:584 __alloc_skb+0x138/0x2c0 net/core/skbuff.c:653 alloc_skb include/linux/skbuff.h:1284 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x293/0xb00 drivers/net/netdevsim/dev.c:851 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