INFO: task kworker/0:2:8500 blocked for more than 143 seconds. Not tainted 5.10.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:26568 pid: 8500 ppid: 2 flags:0x00004000 Workqueue: events mptcp_worker Call Trace: context_switch kernel/sched/core.c:3779 [inline] __schedule+0x893/0x2130 kernel/sched/core.c:4528 schedule+0xcf/0x270 kernel/sched/core.c:4606 __lock_sock+0x13d/0x260 net/core/sock.c:2499 lock_sock_nested+0xf1/0x110 net/core/sock.c:3038 lock_sock include/net/sock.h:1590 [inline] mptcp_worker+0xa6/0x17a0 net/mptcp/protocol.c:2221 process_one_work+0x933/0x15a0 kernel/workqueue.c:2272 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Showing all locks held in the system: 1 lock held by khungtaskd/1651: #0: ffffffff8b3378e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8181: #0: ffff8880140b4370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:932 2 locks held by kworker/0:2/8500: #0: ffff888010064d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010064d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010064d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010064d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010064d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010064d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2243 #1: ffffc900011cfda8 ((work_completion)(&msk->work)){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2247 1 lock held by syz-executor456/8934: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1651 Comm: khungtaskd Not tainted 5.10.0-rc5-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+0x107/0x163 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd43/0xfa0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8934 Comm: syz-executor456 Not tainted 5.10.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5185 [inline] RIP: 0010:lock_is_held_type+0x7e/0x100 kernel/locking/lockdep.c:5476 Code: 85 c0 7f 0f eb 7a 83 c3 01 41 3b 9c 24 10 09 00 00 7d 6d 48 63 c3 48 89 ee 48 8d 04 80 4d 8d 7c c5 00 4c 89 ff e8 62 fc ff ff <85> c0 74 d8 41 83 fe ff 41 bc 01 00 00 00 74 12 41 0f b6 47 22 45 RSP: 0018:ffffc90001d4f430 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff19d9fa3 RDX: 0000000000000000 RSI: ffffffff8b337820 RDI: ffff88801c043d98 RBP: ffffffff8b337820 R08: 0000000000000000 R09: ffffffff8ceccb4f R10: fffffbfff19d9969 R11: 0000000000000000 R12: ffff88801c043480 R13: ffff88801c043d98 R14: 00000000ffffffff R15: ffff88801c043d98 FS: 00007f059124a700(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000006df0c0 CR3: 00000000117dc000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:271 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:123 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x5c9/0x740 kernel/locking/lockdep.c:5408 __might_fault mm/memory.c:5033 [inline] __might_fault+0x106/0x180 mm/memory.c:5018 _copy_to_iter+0x3be/0xf80 lib/iov_iter.c:634 copy_to_iter include/linux/uio.h:137 [inline] simple_copy_to_iter+0x4c/0x70 net/core/datagram.c:519 __skb_datagram_iter+0x4a2/0x760 net/core/datagram.c:448 skb_copy_datagram_iter+0x40/0x50 net/core/datagram.c:533 skb_copy_datagram_msg include/linux/skbuff.h:3532 [inline] __mptcp_recvmsg_mskq net/mptcp/protocol.c:1713 [inline] mptcp_recvmsg+0x571/0x20a0 net/mptcp/protocol.c:1927 inet6_recvmsg+0x11b/0x5d0 net/ipv6/af_inet6.c:654 sock_recvmsg_nosec net/socket.c:885 [inline] sock_recvmsg net/socket.c:903 [inline] sock_recvmsg net/socket.c:899 [inline] ____sys_recvmsg+0x2c4/0x600 net/socket.c:2554 ___sys_recvmsg+0x127/0x200 net/socket.c:2596 do_recvmmsg+0x24d/0x6c0 net/socket.c:2696 __sys_recvmmsg net/socket.c:2775 [inline] __do_sys_recvmmsg net/socket.c:2798 [inline] __se_sys_recvmmsg net/socket.c:2791 [inline] __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2791 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x4499d9 Code: e8 cc 0c 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 5b 04 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0591249db8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00000000006dfc28 RCX: 00000000004499d9 RDX: 0000000000000001 RSI: 0000000020005a80 RDI: 0000000000000003 RBP: 00000000006dfc20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dfc2c R13: 00007ffc9a14b72f R14: 00007f059124a9c0 R15: 00000000006dfc2c