INFO: task syz.1.5045:16348 blocked for more than 145 seconds. Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.5045 state:D stack:28416 pid:16348 tgid:16344 ppid:5813 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 ptmx_open drivers/tty/pty.c:823 [inline] ptmx_open+0xf6/0x350 drivers/tty/pty.c:790 chrdev_open+0x237/0x6a0 fs/char_dev.c:414 do_dentry_open+0x735/0x1c40 fs/open.c:955 vfs_open+0x82/0x3f0 fs/open.c:1085 do_open fs/namei.c:3828 [inline] path_openat+0x1e88/0x2d80 fs/namei.c:3987 do_filp_open+0x20c/0x470 fs/namei.c:4014 do_sys_openat2+0x17a/0x1e0 fs/open.c:1427 do_sys_open fs/open.c:1442 [inline] __do_sys_openat fs/open.c:1458 [inline] __se_sys_openat fs/open.c:1453 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1453 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f896178cd29 RSP: 002b:00007f8962539038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f89619a5fa0 RCX: 00007f896178cd29 RDX: 0000000000000000 RSI: 0000000020002700 RDI: ffffffffffffff9c RBP: 00007f896180e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f89619a5fa0 R15: 00007ffca0d1bae8 INFO: task syz.0.5046:16346 blocked for more than 145 seconds. Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.5046 state:D stack:28416 pid:16346 tgid:16345 ppid:5816 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 tty_open_by_driver drivers/tty/tty_io.c:2046 [inline] tty_open+0x53d/0xf80 drivers/tty/tty_io.c:2129 chrdev_open+0x237/0x6a0 fs/char_dev.c:414 do_dentry_open+0x735/0x1c40 fs/open.c:955 vfs_open+0x82/0x3f0 fs/open.c:1085 do_open fs/namei.c:3828 [inline] path_openat+0x1e88/0x2d80 fs/namei.c:3987 do_filp_open+0x20c/0x470 fs/namei.c:4014 do_sys_openat2+0x17a/0x1e0 fs/open.c:1427 do_sys_open fs/open.c:1442 [inline] __do_sys_openat fs/open.c:1458 [inline] __se_sys_openat fs/open.c:1453 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1453 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa4bb98cd29 RSP: 002b:00007fa4bc721038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fa4bbba5fa0 RCX: 00007fa4bb98cd29 RDX: 0000000000000081 RSI: 0000000020002400 RDI: ffffffffffffff9c RBP: 00007fa4bba0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fa4bbba5fa0 R15: 00007ffd31b9a8f8 Showing all locks held in the system: 3 locks held by kworker/u8:1/12: 3 locks held by kworker/1:0/25: 1 lock held by khungtaskd/30: #0: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 2 locks held by kworker/u8:2/35: 3 locks held by kworker/1:1/51: 6 locks held by kworker/u8:4/67: 2 locks held by kswapd0/88: 2 locks held by kworker/1:2/970: 3 locks held by syslogd/5173: 1 lock held by dhcpcd/5484: 2 locks held by getty/5573: #0: ffff8880367580a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5810: 1 lock held by syz-executor/5814: #0: ffff88814d5ded88 (&xt[i].mutex){+.+.}-{4:4}, at: xt_find_table_lock+0x59/0x520 net/netfilter/x_tables.c:1243 2 locks held by syz-executor/5815: 2 locks held by kworker/1:3/5817: 1 lock held by syz-executor/5828: #0: ffff88814d5ded88 (&xt[i].mutex){+.+.}-{4:4}, at: xt_find_table_lock+0x59/0x520 net/netfilter/x_tables.c:1243 2 locks held by kworker/1:6/5870: 2 locks held by kworker/0:5/5898: 1 lock held by syz.1.5045/16348: #0: ffffffff8ee89908 (tty_mutex){+.+.}-{4:4}, at: ptmx_open drivers/tty/pty.c:823 [inline] #0: ffffffff8ee89908 (tty_mutex){+.+.}-{4:4}, at: ptmx_open+0xf6/0x350 drivers/tty/pty.c:790 1 lock held by syz.0.5046/16346: #0: ffffffff8ee89908 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2046 [inline] #0: ffffffff8ee89908 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53d/0xf80 drivers/tty/tty_io.c:2129 2 locks held by kworker/u8:5/16350: 3 locks held by kworker/u8:9/16351: 3 locks held by syz-executor/16356: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 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:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 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: 67 Comm: kworker/u8:4 Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:check_preemption_disabled+0x25/0xe0 lib/smp_processor_id.c:56 Code: 90 90 90 90 90 41 54 55 53 48 83 ec 08 65 8b 1d bd 5b ae 74 65 8b 05 b2 5b ae 74 a9 ff ff ff 7f 74 0f 48 83 c4 08 89 d8 5b 5d <41> 5c c3 cc cc cc cc 9c 58 f6 c4 02 74 ea 65 48 8b 05 85 5b ae 74 RSP: 0018:ffffc900000075d0 EFLAGS: 00000096 RAX: 0000000000000000 RBX: ffff88801d33c880 RCX: 1ffffffff20c40b1 RDX: 1ffff11003a67a69 RSI: ffffffff8b6cdba0 RDI: ffffffff8bd2fec0 RBP: 58cce5e7c8d5ebdc R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff90624917 R11: 0000000000000005 R12: ffffc900030ae030 R13: ffff88806195eb40 R14: dffffc0000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd0942ae28 CR3: 000000000df80000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:464 [inline] lockdep_hardirqs_on_prepare+0x11b/0x420 kernel/locking/lockdep.c:4407 trace_hardirqs_on+0x36/0x40 kernel/trace/trace_preemptirq.c:78 __local_bh_enable_ip+0xa4/0x120 kernel/softirq.c:394 ebt_do_table+0x1bd1/0x21b0 net/bridge/netfilter/ebtables.c:312 ebt_broute+0x2b2/0x700 net/bridge/netfilter/ebtable_broute.c:61 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:282 [inline] br_handle_frame+0xad7/0x14a0 net/bridge/br_input.c:433 __netif_receive_skb_core.constprop.0+0xa20/0x4330 net/core/dev.c:5722 __netif_receive_skb_one_core+0xb1/0x1e0 net/core/dev.c:5826 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5941 process_backlog+0x443/0x15f0 net/core/dev.c:6289 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7106 napi_poll net/core/dev.c:7175 [inline] net_rx_action+0xa94/0x1010 net/core/dev.c:7297 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 do_softirq kernel/softirq.c:462 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:449 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:389 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x8c7/0xd00 drivers/net/netdevsim/dev.c:851 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 33343 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:c6:72:bc:f4:0c:40, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:c6:72:bc:f4:0c:40, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:c6:72:bc:f4:0c:40, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)