INFO: task kworker/u4:2:26 blocked for more than 143 seconds. Not tainted 5.8.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:2 D23992 26 2 0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:3458 [inline] __schedule+0x8ea/0x2210 kernel/sched/core.c:4219 schedule+0xd0/0x2a0 kernel/sched/core.c:4294 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4353 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10d0 kernel/locking/mutex.c:1103 ip_set_net_exit+0x192/0x650 net/netfilter/ipset/ip_set_core.c:2404 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:186 cleanup_net+0x4ea/0xa00 net/core/net_namespace.c:603 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 INFO: task syz-executor.2:11344 blocked for more than 143 seconds. Not tainted 5.8.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D25176 11344 7024 0x00004004 Call Trace: context_switch kernel/sched/core.c:3458 [inline] __schedule+0x8ea/0x2210 kernel/sched/core.c:4219 schedule+0xd0/0x2a0 kernel/sched/core.c:4294 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4353 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10d0 kernel/locking/mutex.c:1103 nfnl_lock net/netfilter/nfnetlink.c:63 [inline] nfnetlink_rcv_msg+0x912/0xea0 net/netfilter/nfnetlink.c:225 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2469 nfnetlink_rcv+0x1ac/0x420 net/netfilter/nfnetlink.c:564 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 sock_no_sendpage+0xee/0x130 net/core/sock.c:2853 kernel_sendpage net/socket.c:3642 [inline] sock_sendpage+0xe5/0x140 net/socket.c:945 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:448 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x3dc/0x830 fs/splice.c:626 splice_from_pipe fs/splice.c:661 [inline] generic_splice_sendpage+0xd4/0x140 fs/splice.c:834 do_splice_from fs/splice.c:846 [inline] direct_splice_actor+0x171/0x2f0 fs/splice.c:1016 splice_direct_to_actor+0x38c/0x980 fs/splice.c:971 do_splice_direct+0x1b3/0x280 fs/splice.c:1059 do_sendfile+0x559/0xc30 fs/read_write.c:1540 __do_sys_sendfile64 fs/read_write.c:1601 [inline] __se_sys_sendfile64 fs/read_write.c:1587 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1587 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cc79 Code: Bad RIP value. RSP: 002b:00007fd71202dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000026b80 RCX: 000000000045cc79 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000007 RBP: 000000000078bfe8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000100000002 R11: 0000000000000246 R12: 000000000078bfac R13: 00007fff9185361f R14: 00007fd71202e9c0 R15: 000000000078bfac Showing all locks held in the system: 4 locks held by kworker/u4:2/26: #0: ffff88821b03c138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88821b03c138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff88821b03c138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff88821b03c138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff88821b03c138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff88821b03c138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90000e27da8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8a7b0f70 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa00 net/core/net_namespace.c:565 #3: ffffffff8d4c3518 (&table[i].mutex){+.+.}-{3:3}, at: ip_set_net_exit+0x192/0x650 net/netfilter/ipset/ip_set_core.c:2404 1 lock held by khungtaskd/1154: #0: ffffffff89bc11c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 1 lock held by in:imklog/6523: #0: ffff88809374d370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 1 lock held by syz-executor.1/11333: 1 lock held by syz-executor.2/11344: #0: ffffffff8d4c3518 (&table[i].mutex){+.+.}-{3:3}, at: nfnl_lock net/netfilter/nfnetlink.c:63 [inline] #0: ffffffff8d4c3518 (&table[i].mutex){+.+.}-{3:3}, at: nfnetlink_rcv_msg+0x912/0xea0 net/netfilter/nfnetlink.c:225 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1154 Comm: khungtaskd Not tainted 5.8.0-rc6-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+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 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+0xd7d/0x1000 kernel/hung_task.c:295 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 17521 Comm: kworker/u4:1 Not tainted 5.8.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:lock_release+0x57/0x8d0 kernel/locking/lockdep.c:4967 Code: 24 10 48 c7 44 24 18 70 98 68 89 48 c1 ed 03 48 c7 44 24 20 10 04 5a 81 48 8d 44 15 00 c7 00 f1 f1 f1 f1 c7 40 04 f1 f1 04 f2 40 08 04 f3 f3 f3 65 48 8b 1c 25 00 ff 01 00 65 48 8b 04 25 28 RSP: 0018:ffffc90001a27bb8 EFLAGS: 00000a02 RAX: fffff52000344f79 RBX: 0000000000000001 RCX: ffffffff87cd2a88 RDX: dffffc0000000000 RSI: ffffffff87cd2791 RDI: ffffffff89bc11c0 RBP: 1ffff92000344f79 R08: 0000000000000000 R09: ffffffff8c5a5a27 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff89bc11c0 R13: ffffffff87cd2791 R14: dffffc0000000000 R15: 000000000000011d FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000564000d64490 CR3: 0000000038da3000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:246 [inline] rcu_read_unlock include/linux/rcupdate.h:688 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline] batadv_nc_worker+0x7a3/0xe50 net/batman-adv/network-coding.c:718 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293