INFO: task syz.1.613:8393 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.613 state:D stack:25128 pid:8393 tgid:8393 ppid:5836 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 request_wait_answer fs/fuse/dev.c:565 [inline] __fuse_request_send fs/fuse/dev.c:579 [inline] __fuse_simple_request+0xf1b/0x18e0 fs/fuse/dev.c:673 fuse_simple_request fs/fuse/fuse_i.h:1244 [inline] fuse_flush+0x5dd/0x810 fs/fuse/file.c:476 filp_flush+0xc0/0x190 fs/open.c:1547 filp_close+0x1d/0x40 fs/open.c:1560 __range_close fs/file.c:767 [inline] __do_sys_close_range fs/file.c:826 [inline] __se_sys_close_range+0x35c/0x650 fs/file.c:790 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f502fcfeba9 RSP: 002b:00007ffcf1d0a0d8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00007f502ff47da0 RCX: 00007f502fcfeba9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f502ff47da0 R08: 000000000000b2e4 R09: 0000000cf1d0a3cf R10: 00007f502ff47cb0 R11: 0000000000000246 R12: 0000000000072658 R13: 00007ffcf1d0a1d0 R14: ffffffffffffffff R15: 00007ffcf1d0a1f0 INFO: task syz.1.613:8399 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.613 state:D stack:25752 pid:8399 tgid:8393 ppid:5836 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 request_wait_answer fs/fuse/dev.c:565 [inline] __fuse_request_send fs/fuse/dev.c:579 [inline] __fuse_simple_request+0xf1b/0x18e0 fs/fuse/dev.c:673 fuse_simple_request fs/fuse/fuse_i.h:1244 [inline] fuse_do_getattr+0x33e/0x620 fs/fuse/dir.c:1317 fuse_update_get_attr+0x51b/0x10f0 fs/fuse/dir.c:1374 vfs_getattr_nosec+0x2de/0x430 fs/stat.c:213 vfs_getattr fs/stat.c:262 [inline] vfs_statx_path fs/stat.c:299 [inline] vfs_statx+0x1b4/0x550 fs/stat.c:356 vfs_fstatat+0x118/0x170 fs/stat.c:375 __do_sys_newfstatat fs/stat.c:542 [inline] __se_sys_newfstatat fs/stat.c:536 [inline] __x64_sys_newfstatat+0x116/0x190 fs/stat.c:536 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f502fcfeba9 RSP: 002b:00007f502df45038 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 00007f502ff46090 RCX: 00007f502fcfeba9 RDX: 0000000000000000 RSI: 00002000000008c0 RDI: ffffffffffffff9c RBP: 00007f502fd81e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f502ff46128 R14: 00007f502ff46090 R15: 00007ffcf1d09f78 Showing all locks held in the system: 4 locks held by kworker/0:0/9: 1 lock held by khungtaskd/38: #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by udevd/5208: 2 locks held by getty/5594: #0: ffff88823bf308a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5848: 2 locks held by kworker/u8:15/6281: 9 locks held by syz-executor/8509: 2 locks held by syz.5.1646/11617: 1 lock held by syz.6.1703/11760: #0: ffffffff8ecd3578 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8ecd3578 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3433 6 locks held by syz.7.1704/11763: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/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+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 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: 9 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: events_power_efficient gc_worker RIP: 0010:__lock_acquire+0x111/0xd20 kernel/locking/lockdep.c:5145 Code: e2 9e 92 48 29 c8 48 c1 f8 03 48 be 29 5c 8f c2 f5 28 5c 8f 48 0f af f0 45 85 f6 0f 85 4a 01 00 00 45 85 ed 0f 84 41 01 00 00 <41> 83 fd 31 0f 83 12 01 00 00 48 83 7c 24 68 00 0f 84 2b 01 00 00 RSP: 0018:ffffc900000e7730 EFLAGS: 00000006 RAX: 000000000000b3e2 RBX: ffffffff8f1de528 RCX: ffffffff929ee2f0 RDX: 0000000000000003 RSI: 0000000000000732 RDI: ffff88801c2c0000 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: dffffc0000000000 R11: fffffbfff1e3abe7 R12: 0000000000000002 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881268bd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555572af55c8 CR3: 0000000048448000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 seqcount_lockdep_reader_access+0x10b/0x1c0 include/linux/seqlock.h:72 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:342 [inline] gc_worker+0x31f/0x13f0 net/netfilter/nf_conntrack_core.c:1548 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245