INFO: task syz.3.2102:18851 blocked for more than 143 seconds. Not tainted 6.11.0-rc4-syzkaller #0 Showing all locks held in the system: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 21554 Comm: syz.3.3010 Not tainted 6.11.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:remove_class_from_lock_chain kernel/locking/lockdep.c:6084 [inline] RIP: 0010:remove_class_from_lock_chains kernel/locking/lockdep.c:6123 [inline] RIP: 0010:zap_class+0x247/0x9a0 kernel/locking/lockdep.c:6165 Code: 00 0f 85 f6 06 00 00 49 8b 2c 24 48 85 ed 0f 84 c2 00 00 00 48 83 ed 08 0f 84 b8 00 00 00 48 89 e8 48 c1 e8 03 42 0f b6 04 38 <84> c0 74 08 3c 03 0f 8e 94 05 00 00 0f b6 45 00 44 8b 6d 00 c0 e8 RSP: 0018:ffffc900047f7990 EFLAGS: 00000806 RAX: 0000000000000000 RBX: ffffffff94622698 RCX: ffffffff8167a3d5 RDX: 0000000000000ce9 RSI: 000000000000002c RDI: 0000000000000000 RBP: ffffffff935976c0 R08: ffffffff932bc5aa R09: 000000000002d115 R10: ffffffff9462a85f R11: 0000000000000000 R12: ffffffff9451b250 R13: 000000000002d10d R14: ffffffff93623428 R15: dffffc0000000000 FS: 000055555b467500(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff7100e8178 CR3: 0000000024860000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lockdep_free_key_range+0x56/0x110 kernel/locking/lockdep.c:6284 lockdep_unregister_key+0x18c/0x280 kernel/locking/lockdep.c:6480 __qdisc_destroy+0x11a/0x4a0 net/sched/sch_generic.c:1079 qdisc_put+0xab/0xe0 net/sched/sch_generic.c:1105 shutdown_scheduler_queue+0xa5/0x160 net/sched/sch_generic.c:1158 netdev_for_each_tx_queue include/linux/netdevice.h:2513 [inline] dev_shutdown+0xac/0x430 net/sched/sch_generic.c:1490 unregister_netdevice_many_notify+0x620/0x1e40 net/core/dev.c:11342 unregister_netdevice_many net/core/dev.c:11414 [inline] unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11289 unregister_netdevice include/linux/netdevice.h:3129 [inline] __tun_detach+0x11cc/0x14a0 drivers/net/tun.c:685 tun_detach drivers/net/tun.c:701 [inline] tun_chr_close+0xc8/0x230 drivers/net/tun.c:3510 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcb04979e79 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe1c9ab2a8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fcb04b17a80 RCX: 00007fcb04979e79 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fcb04b17a80 R08: 00007fcb04b02000 R09: 00007ffe1c9ab58f R10: 00000000003ffd40 R11: 0000000000000246 R12: 00000000001d8db3 R13: 00007ffe1c9ab3a0 R14: 00007ffe1c9ab3c0 R15: ffffffffffffffff