INFO: task syslogd:5171 blocked for more than 143 seconds. Not tainted 6.13.0-rc7-syzkaller-00209-g9528d418de4d #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syslogd state:D stack:24208 pid:5171 tgid:5171 ppid:1 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75 ___down_common+0x2d7/0x460 kernel/locking/semaphore.c:225 __down_common kernel/locking/semaphore.c:246 [inline] __down+0x20/0x30 kernel/locking/semaphore.c:254 down+0x74/0xa0 kernel/locking/semaphore.c:63 console_lock+0x5b/0xa0 kernel/printk/printk.c:2833 console_device+0x19/0x180 kernel/printk/printk.c:3482 tty_lookup_driver+0x2fb/0x510 drivers/tty/tty_io.c:1930 tty_open_by_driver drivers/tty/tty_io.c:2047 [inline] tty_open+0x54e/0xf80 drivers/tty/tty_io.c:2129 chrdev_open+0x237/0x6a0 fs/char_dev.c:414 do_dentry_open+0xf59/0x1ea0 fs/open.c:945 vfs_open+0x82/0x3f0 fs/open.c:1075 do_open fs/namei.c:3828 [inline] path_openat+0x1e6a/0x2d60 fs/namei.c:3987 do_filp_open+0x20c/0x470 fs/namei.c:4014 do_sys_openat2+0x17a/0x1e0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1428 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: 0033:0x7fa64020b9a4 RSP: 002b:00007ffea1906480 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa64020b9a4 RDX: 0000000000000901 RSI: 00007fa6403aa3b3 RDI: 00000000ffffff9c RBP: 00007fa6403aa3b3 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000901 R13: 0000000000000901 R14: 0000000000000901 R15: 000055758d3ed410 Showing all locks held in the system: 3 locks held by kworker/u8:1/12: 1 lock held by khungtaskd/30: #0: ffffffff8e1bb900 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bb900 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bb900 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6744 5 locks held by kworker/u8:2/35: 3 locks held by kworker/u8:4/62: 3 locks held by kworker/u8:7/4367: 1 lock held by syslogd/5171: #0: ffffffff8ee71e68 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2046 [inline] #0: ffffffff8ee71e68 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53d/0xf80 drivers/tty/tty_io.c:2129 3 locks held by udevd/5189: 1 lock held by dhcpcd/5482: 4 locks held by dhcpcd/5483: 2 locks held by getty/5572: #0: ffff8880376720a0 (&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 5 locks held by kworker/1:3/5822: 1 lock held by syz-executor/6200: 1 lock held by syz-executor/6203: 2 locks held by syz-executor/6204: 1 lock held by syz-executor/6213: 5 locks held by kworker/0:4/6248: 3 locks held by kworker/0:5/6250: #0: ffff88801b078948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90003defd80 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffffffff8fee0048 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 6 locks held by syz.3.5841/17810: 3 locks held by kworker/u8:8/17833: 3 locks held by kworker/u8:11/17839: #0: ffff88801b081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000c577d80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffffffff8fee0048 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:285 1 lock held by kworker/u8:4/17842: 2 locks held by syz-executor/17843: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc7-syzkaller-00209-g9528d418de4d #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:234 [inline] watchdog+0xf14/0x1240 kernel/hung_task.c:397 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: 12 Comm: kworker/u8:1 Not tainted 6.13.0-rc7-syzkaller-00209-g9528d418de4d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: bat_events batadv_tt_purge RIP: 0010:find_match+0x6a/0x15d0 net/ipv6/route.c:739 Code: 89 b5 64 ff ff ff 4c 89 85 68 ff ff ff 4c 89 8d 50 ff ff ff 48 c7 85 70 ff ff ff b3 8a b5 41 48 c7 85 78 ff ff ff 68 a1 90 8d <48> c7 45 80 30 f6 da 89 c7 00 f1 f1 f1 f1 c7 40 04 00 f2 f2 f2 c7 RSP: 0018:ffffc900000073c8 EFLAGS: 00000292 RAX: fffff52000000e88 RBX: 0000000000000003 RCX: 0000000000000003 RDX: 000000000000001e RSI: 0000000000000001 RDI: ffff88802552fcb8 RBP: ffffc900000074d0 R08: ffffc900000076e0 R09: ffffc900000076d0 R10: 0000000000000000 R11: 0000000000000003 R12: ffff88802552fccf R13: ffff88802552fcb8 R14: 1ffff92000000e88 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc5f26d6ff8 CR3: 000000000df7e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __find_rr_leaf+0x141/0xe00 net/ipv6/route.c:835 find_rr_leaf net/ipv6/route.c:856 [inline] rt6_select net/ipv6/route.c:900 [inline] fib6_table_lookup+0x57e/0xa30 net/ipv6/route.c:2195 ip6_pol_route+0x1cd/0x1120 net/ipv6/route.c:2231 pol_lookup_func include/net/ip6_fib.h:616 [inline] fib6_rule_lookup+0x536/0x720 net/ipv6/fib6_rules.c:117 ip6_route_input_lookup net/ipv6/route.c:2300 [inline] ip6_route_input+0x663/0xc10 net/ipv6/route.c:2596 ip6_rcv_finish_core.constprop.0+0x1a0/0x5d0 net/ipv6/ip6_input.c:66 ip6_rcv_finish net/ipv6/ip6_input.c:77 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] ipv6_rcv+0x1e4/0x680 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core+0x12e/0x1e0 net/core/dev.c:5704 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5817 process_backlog+0x443/0x15f0 net/core/dev.c:6149 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6902 napi_poll net/core/dev.c:6971 [inline] net_rx_action+0xa94/0x1010 net/core/dev.c:7093 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] batadv_tt_global_purge net/batman-adv/translation-table.c:2272 [inline] batadv_tt_purge+0x251/0xb90 net/batman-adv/translation-table.c:3532 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+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