INFO: task syz-executor.0:9180 blocked for more than 143 seconds. Not tainted 5.5.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27376 9180 9162 0x00000004 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4214 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ovs_lock net/openvswitch/datapath.c:105 [inline] ovs_dp_cmd_new+0x50d/0xe40 net/openvswitch/datapath.c:1688 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline] genl_family_rcv_msg net/netlink/genetlink.c:717 [inline] genl_rcv_msg+0x67d/0xea0 net/netlink/genetlink.c:734 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 genl_rcv+0x29/0x40 net/netlink/genetlink.c:745 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x58c/0x7d0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:659 ____sys_sendmsg+0x753/0x880 net/socket.c:2330 ___sys_sendmsg+0x100/0x170 net/socket.c:2384 __sys_sendmsg+0x105/0x1d0 net/socket.c:2417 __do_sys_sendmsg net/socket.c:2426 [inline] __se_sys_sendmsg net/socket.c:2424 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2424 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45b349 Code: Bad RIP value. RSP: 002b:00007f2f5258cc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f2f5258d6d4 RCX: 000000000045b349 RDX: 84af050000000000 RSI: 0000000020000280 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009ba R14: 00000000004cb2b4 R15: 000000000075bf2c Showing all locks held in the system: 4 locks held by kworker/u4:4/433: #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2235 #1: ffffc900025c7dc0 (net_cleanup_work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239 #2: ffffffff8a4b9c48 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0xaf0 net/core/net_namespace.c:559 #3: ffffffff8a7214e0 (ovs_mutex){+.+.}, at: ovs_lock net/openvswitch/datapath.c:105 [inline] #3: ffffffff8a7214e0 (ovs_mutex){+.+.}, at: ovs_exit_net+0x201/0xc30 net/openvswitch/datapath.c:2469 1 lock held by khungtaskd/1076: #0: ffffffff899a1300 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5333 3 locks held by rs:main Q:Reg/9793: #0: ffff8880ae837358 (&rq->lock){-.-.}, at: newidle_balance+0xa28/0xe80 kernel/sched/fair.c:10177 #1: ffffffff899a1300 (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:5729 #2: ffff88808e07b508 (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:791 [inline] #2: ffff88808e07b508 (&sb->s_type->i_mutex_key#11){+.+.}, at: ext4_buffered_write_iter+0xba/0x460 fs/ext4/file.c:246 1 lock held by rsyslogd/9795: #0: ffff88809a077920 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9885: #0: ffff8880985e4090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900018ab2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9886: #0: ffff88809a7ab090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900018cb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9887: #0: ffff8880985e5090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900018bb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9888: #0: ffff888095554090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000184b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9889: #0: ffff88808b729090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000183b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9890: #0: ffff888096ede090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000187b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9891: #0: ffff8880a74a3090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000180b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.0/9180: #0: ffffffff8a517e28 (cb_lock){++++}, at: genl_rcv+0x1a/0x40 net/netlink/genetlink.c:744 #1: ffffffff8a7214e0 (ovs_mutex){+.+.}, at: ovs_lock net/openvswitch/datapath.c:105 [inline] #1: ffffffff8a7214e0 (ovs_mutex){+.+.}, at: ovs_dp_cmd_new+0x50d/0xe40 net/openvswitch/datapath.c:1688 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1076 Comm: khungtaskd Not tainted 5.5.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb11/0x10c0 kernel/hung_task.c:289 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60