INFO: task syz.3.10234:29619 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.10234 state:D stack:24568 pid:29619 tgid:29619 ppid:12239 task_flags:0x400040 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 request_wait_answer fs/fuse/dev.c:585 [inline] __fuse_request_send fs/fuse/dev.c:599 [inline] __fuse_simple_request+0x121f/0x1c60 fs/fuse/dev.c:693 fuse_simple_request fs/fuse/fuse_i.h:1263 [inline] fuse_flush+0x66a/0x8a0 fs/fuse/file.c:494 filp_flush+0xbd/0x190 fs/open.c:1533 filp_close+0x1d/0x40 fs/open.c:1546 __range_close fs/file.c:790 [inline] __do_sys_close_range fs/file.c:849 [inline] __se_sys_close_range+0x372/0x670 fs/file.c:813 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcc88f9aeb9 RSP: 002b:00007fff42be2a78 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00007fff42be2b60 RCX: 00007fcc88f9aeb9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00000000001b547d R08: 0000000000000001 R09: 0000000000000000 R10: 0000001b2f720000 R11: 0000000000000246 R12: 00007fff42be2ba0 R13: 00007fcc8921609c R14: 00000000001b5543 R15: 00007fcc89216090 Showing all locks held in the system: 1 lock held by khungtaskd/32: #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5576: #0: ffff888034f4d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 2 locks held by kworker/u8:11/506: #0: ffff8881416a3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff8881416a3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000e9afbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000e9afbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 4 locks held by kworker/u8:22/578: #0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639 #1: ffff888063390a68 (&p->pi_lock){-.-.}-{2:2}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffff888063390a68 (&p->pi_lock){-.-.}-{2:2}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 #3: ffffffff9a27a3e0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x83/0x580 lib/debugobjects.c:818 3 locks held by syz.9.10682/626: #0: ffff88807d6ab5f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1255 #1: ffff88807bec0420 (sb_writers#17){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2683 [inline] #1: ffff88807bec0420 (sb_writers#17){.+.+}-{0:0}, at: vfs_writev+0x2aa/0x990 fs/read_write.c:1055 #2: ffff888054bab948 (&sb->s_type->i_mutex_key#32){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #2: ffff888054bab948 (&sb->s_type->i_mutex_key#32){+.+.}-{4:4}, at: fuse_fsync+0x111/0x310 fs/fuse/file.c:540 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 32323 Comm: kworker/u8:10 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:__unwind_start+0x592/0x760 arch/x86/kernel/unwind_orc.c:772 Code: 0f 92 c2 20 ca 80 fa 01 75 3e 48 8b 54 24 20 4c 39 e2 0f 97 c1 48 39 c2 0f 96 c0 20 c8 3c 01 75 27 48 8b 44 24 08 80 3c 30 00 <4c> 8b 64 24 18 74 08 4c 89 e7 e8 ef 07 b7 00 48 8b 44 24 10 49 39 RSP: 0018:ffffc90003b77528 EFLAGS: 00000246 RAX: 1ffff9200076eeb8 RBX: ffffc90003b77588 RCX: 0000000000000001 RDX: ffffc90003b77618 RSI: dffffc0000000000 RDI: ffffc90003b77528 RBP: 1ffff9200076eeb2 R08: ffffc90003b77501 R09: ffffc90003b77588 R10: dffffc0000000000 R11: fffff5200076eebd R12: ffffc90003b70000 R13: ffffc90003b77598 R14: 1ffff9200076eeb3 R15: ffffc90003b77590 FS: 0000000000000000(0000) GS:ffff8881256f5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055acb64bea38 CR3: 000000000e346000 CR4: 0000000000350ef0 Call Trace: unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6674 [inline] kmem_cache_free+0x195/0x610 mm/slub.c:6785 nsim_dev_trap_report drivers/net/netdevsim/dev.c:891 [inline] nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:921 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246