INFO: task syz-executor.4:4113 blocked for more than 143 seconds. Not tainted 5.4.0-rc4+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28584 4113 9676 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x13e/0x170 net/netlink/genetlink.c:652 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 genl_rcv+0x29/0x40 net/netlink/genetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x803/0x920 net/socket.c:2311 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2363 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f6ebcfb89c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f6ebcfb8a58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f6ebcfb8a00 RDI: 0000000000000007 RBP: 0000000000000007 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f6ebcfb8a40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff INFO: task syz-executor.4:4116 blocked for more than 143 seconds. Not tainted 5.4.0-rc4+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D27832 4116 9676 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x13e/0x170 net/netlink/genetlink.c:652 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 genl_rcv+0x29/0x40 net/netlink/genetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x803/0x920 net/socket.c:2311 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2363 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f6ebcf979c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f6ebcf97a58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f6ebcf97a00 RDI: 0000000000000007 RBP: 0000000000000007 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f6ebcf97a40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1070: #0: ffffffff88fab380 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5337 1 lock held by rsyslogd/9490: #0: ffff888083aa6de0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9613: #0: ffff88809bc61090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f712e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9614: #0: ffff88809cd35090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f6d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9615: #0: ffff8880a3d2b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f692e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9616: #0: ffff8880a9ae4090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f812e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9617: #0: ffff8880a0cb6090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f852e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9618: #0: ffff8880a6002090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f752e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9619: #0: ffff8880a4571090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f4d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.0/4108: 2 locks held by syz-executor.4/4113: #0: ffffffff899f4648 (cb_lock){++++}, at: genl_rcv+0x1a/0x40 net/netlink/genetlink.c:664 #1: ffffffff899f4700 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff899f4700 (genl_mutex){+.+.}, at: genl_rcv_msg+0x13e/0x170 net/netlink/genetlink.c:652 2 locks held by syz-executor.4/4116: #0: ffffffff899f4648 (cb_lock){++++}, at: genl_rcv+0x1a/0x40 net/netlink/genetlink.c:664 #1: ffffffff899f4700 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff899f4700 (genl_mutex){+.+.}, at: genl_rcv_msg+0x13e/0x170 net/netlink/genetlink.c:652 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1070 Comm: khungtaskd Not tainted 5.4.0-rc4+ #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+0x172/0x1f0 lib/dump_stack.c:113 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+0x9d0/0xef0 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 CPU: 0 PID: 4108 Comm: syz-executor.0 Not tainted 5.4.0-rc4+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rcu_lockdep_current_cpu_online kernel/rcu/tree.c:949 [inline] RIP: 0010:rcu_lockdep_current_cpu_online+0x65/0x130 kernel/rcu/tree.c:940 Code: c3 c0 5a 03 00 48 ba 00 00 00 00 00 fc ff df 89 c0 48 8d 3c c5 40 81 bc 88 48 89 f9 48 c1 e9 03 80 3c 11 00 0f 85 9d 00 00 00 <48> 03 1c c5 40 81 bc 88 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 18 RSP: 0018:ffff888058ffec58 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000035ac0 RCX: 1ffffffff1179028 RDX: dffffc0000000000 RSI: ffffffff8347219c RDI: ffffffff88bc8140 RBP: ffff888058ffec70 R08: ffff888081868180 R09: ffffed1015d06b75 R10: ffffed1015d06b74 R11: ffff8880ae835ba3 R12: 0000000000000001 R13: ffff888069470000 R14: ffff888069474711 R15: 0000000000000000 FS: 00007f45ae945700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 000000005b47e000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:109 [inline] rcu_read_lock_held_common+0xbd/0x130 kernel/rcu/update.c:99 rcu_read_lock_held+0x5b/0xb0 kernel/rcu/update.c:281 __rhashtable_lookup include/linux/rhashtable.h:621 [inline] rhashtable_lookup include/linux/rhashtable.h:645 [inline] rhashtable_lookup_fast include/linux/rhashtable.h:671 [inline] tipc_sk_lookup+0xb37/0xbf0 net/tipc/socket.c:2807 tipc_nl_publ_dump+0x1f8/0xd70 net/tipc/socket.c:3616 __tipc_nl_compat_dumpit.isra.0+0x21a/0x930 net/tipc/netlink_compat.c:207 tipc_nl_compat_publ_dump net/tipc/netlink_compat.c:1002 [inline] tipc_nl_compat_sk_dump+0x54d/0x970 net/tipc/netlink_compat.c:1054 __tipc_nl_compat_dumpit.isra.0+0x320/0x930 net/tipc/netlink_compat.c:216 tipc_nl_compat_dumpit+0x24c/0x510 net/tipc/netlink_compat.c:288 tipc_nl_compat_handle net/tipc/netlink_compat.c:1253 [inline] tipc_nl_compat_recv+0x5a0/0xae0 net/tipc/netlink_compat.c:1291 genl_family_rcv_msg+0x74b/0xf90 net/netlink/genetlink.c:629 genl_rcv_msg+0xca/0x170 net/netlink/genetlink.c:654 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 genl_rcv+0x29/0x40 net/netlink/genetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x803/0x920 net/socket.c:2311 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2363 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459f39 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f45ae944c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f39 RDX: 000000007a000000 RSI: 0000000020000500 RDI: 0000000000000004 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f45ae9456d4 R13: 00000000004cf980 R14: 00000000004de090 R15: 00000000ffffffff