INFO: task kworker/u4:3:120 blocked for more than 143 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:3 state:D stack:24808 pid: 120 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 ip6gre_exit_batch_net+0x88/0x750 net/ipv6/ip6_gre.c:1606 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:189 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:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 INFO: task kworker/1:4:8191 blocked for more than 143 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:4 state:D stack:25792 pid: 8191 ppid: 2 flags:0x00004000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 linkwatch_event+0xb/0x60 net/core/link_watch.c:250 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 INFO: task syz-executor.1:28731 blocked for more than 144 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:29832 pid:28731 ppid: 6896 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 raw_init+0x296/0x340 net/can/raw.c:339 can_create+0x27c/0x4d0 net/can/af_can.c:168 __sock_create+0x3de/0x780 net/socket.c:1427 sock_create net/socket.c:1478 [inline] __sys_socket+0xef/0x200 net/socket.c:1520 __do_sys_socket net/socket.c:1529 [inline] __se_sys_socket net/socket.c:1527 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1527 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45dea9 Code: Bad RIP value. RSP: 002b:00007fd99da9bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000034300 RCX: 000000000045dea9 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffcb0a0d6af R14: 00007fd99da9c9c0 R15: 000000000118bf2c INFO: task syz-executor.1:28743 blocked for more than 144 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:29832 pid:28743 ppid: 6896 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 raw_init+0x296/0x340 net/can/raw.c:339 can_create+0x27c/0x4d0 net/can/af_can.c:168 __sock_create+0x3de/0x780 net/socket.c:1427 sock_create net/socket.c:1478 [inline] __sys_socket+0xef/0x200 net/socket.c:1520 __do_sys_socket net/socket.c:1529 [inline] __se_sys_socket net/socket.c:1527 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1527 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45dea9 Code: Bad RIP value. RSP: 002b:00007fd99da7ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000034300 RCX: 000000000045dea9 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000118c008 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bfd4 R13: 00007ffcb0a0d6af R14: 00007fd99da7b9c0 R15: 000000000118bfd4 INFO: task syz-executor.0:28737 blocked for more than 144 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:24704 pid:28737 ppid: 6894 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2353 ___sys_sendmsg+0xf3/0x170 net/socket.c:2407 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2440 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45dea9 Code: Bad RIP value. RSP: 002b:00007f20ac709c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002e5c0 RCX: 000000000045dea9 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000004 RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffd3fa864cf R14: 00007f20ac70a9c0 R15: 000000000118bf2c INFO: task syz-executor.0:28767 blocked for more than 145 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:28320 pid:28767 ppid: 6894 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x331/0x810 net/socket.c:2353 ___sys_sendmsg+0xf3/0x170 net/socket.c:2407 __sys_sendmmsg+0x195/0x480 net/socket.c:2497 __do_sys_sendmmsg net/socket.c:2526 [inline] __se_sys_sendmmsg net/socket.c:2523 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2523 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45dea9 Code: Bad RIP value. RSP: 002b:00007f20ac6a6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000027f40 RCX: 000000000045dea9 RDX: 010efe10675dec16 RSI: 0000000020000200 RDI: 0000000000000003 RBP: 000000000118c160 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118c124 R13: 00007ffd3fa864cf R14: 00007f20ac6a79c0 R15: 000000000118c124 INFO: task kworker/0:24:28740 blocked for more than 145 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:24 state:D stack:28752 pid:28740 ppid: 2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4568 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Showing all locks held in the system: 4 locks held by kworker/u4:3/120: #0: ffff8880a9797138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a9797138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880a9797138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880a9797138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880a9797138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880a9797138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90000fa7da8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8b13bdb0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa00 net/core/net_namespace.c:565 #3: ffffffff8b14d648 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0x88/0x750 net/ipv6/ip6_gre.c:1606 1 lock held by khungtaskd/1172: #0: ffffffff8a067f00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5852 2 locks held by in:imklog/6572: 3 locks held by kworker/1:4/8191: #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90016247da8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8b14d648 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:250 4 locks held by kworker/u4:7/18594: #0: ffff8880ae535e18 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1292 [inline] #0: ffff8880ae535e18 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x287/0x2280 kernel/sched/core.c:4445 #1: ffff8880ae520ec8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x305/0x440 kernel/sched/psi.c:833 #2: ffff88805a504d00 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1007 [inline] #2: ffff88805a504d00 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x93/0xe80 net/mac80211/ibss.c:1682 #3: ffffffff8a067f00 (rcu_read_lock){....}-{1:2}, at: sdata_assert_lock net/mac80211/ieee80211_i.h:1024 [inline] #3: ffffffff8a067f00 (rcu_read_lock){....}-{1:2}, at: ieee80211_sta_active_ibss+0x86/0x350 net/mac80211/ibss.c:659 1 lock held by syz-executor.1/28731: #0: ffffffff8b13bdb0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 1 lock held by syz-executor.1/28743: #0: ffffffff8b13bdb0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 1 lock held by syz-executor.0/28737: #0: ffffffff8b14d648 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8b14d648 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 1 lock held by syz-executor.0/28745: 1 lock held by syz-executor.0/28767: #0: ffffffff8b14d648 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8b14d648 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 3 locks held by kworker/0:23/28738: #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc900073e7da8 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8b14d648 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 3 locks held by kworker/0:24/28740: #0: ffff888214e5dd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888214e5dd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888214e5dd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888214e5dd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888214e5dd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888214e5dd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90007477da8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8b14d648 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4568 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1172 Comm: khungtaskd Not tainted 5.9.0-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+0x198/0x1fd 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:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 18594 Comm: kworker/u4:7 Not tainted 5.9.0-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_acquire+0xcba/0x5780 kernel/locking/lockdep.c:4444 Code: 08 84 d2 0f 85 af 44 00 00 8b 0d 8d f1 fd 09 85 c9 0f 84 00 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 54 24 60 48 c1 ea 03 <80> 3c 02 00 0f 85 b0 44 00 00 48 8b 14 24 4c 89 b5 d8 08 00 00 48 RSP: 0018:ffffc90007467a40 EFLAGS: 00000802 RAX: dffffc0000000000 RBX: 000000006c9008d9 RCX: 0000000000000001 RDX: 1ffff1100ace699b RSI: a46c38c1edde4529 RDI: 000000008750cd03 RBP: ffff888056734400 R08: 0000000000000000 R09: ffffffff8d0c09e7 R10: fffffbfff1a1813c R11: 0000000000000000 R12: ffff888056734d38 R13: 0000000000000000 R14: a46c38c1edde4529 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9fc6ebf000 CR3: 0000000097ff9000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1f3/0xaf0 kernel/locking/lockdep.c:5029 rcu_lock_acquire include/linux/rcupdate.h:241 [inline] rcu_read_lock include/linux/rcupdate.h:634 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline] batadv_nc_worker+0x12d/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:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294