INFO: task syz-executor.3:18603 blocked for more than 140 seconds. Not tainted 4.19.95-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D29496 18603 13392 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1643 raw_init+0x299/0x340 net/can/raw.c:343 can_create+0x288/0x4b0 net/can/af_can.c:184 __sock_create+0x3d8/0x730 net/socket.c:1276 sock_create net/socket.c:1316 [inline] __sys_socket+0x103/0x220 net/socket.c:1346 __do_sys_socket net/socket.c:1355 [inline] __se_sys_socket net/socket.c:1353 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1353 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45af49 Code: Bad RIP value. RSP: 002b:00007f47a5471c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045af49 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f47a54726d4 R13: 00000000004cb896 R14: 00000000004e6118 R15: 00000000ffffffff INFO: task syz-executor.3:18608 blocked for more than 140 seconds. Not tainted 4.19.95-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D26968 18608 13392 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1643 raw_init+0x299/0x340 net/can/raw.c:343 can_create+0x288/0x4b0 net/can/af_can.c:184 __sock_create+0x3d8/0x730 net/socket.c:1276 sock_create net/socket.c:1316 [inline] __sys_socket+0x103/0x220 net/socket.c:1346 __do_sys_socket net/socket.c:1355 [inline] __se_sys_socket net/socket.c:1353 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1353 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45af49 Code: Bad RIP value. RSP: 002b:00007f47a5450c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045af49 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f47a54516d4 R13: 00000000004cb896 R14: 00000000004e6118 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1077: #0: 0000000086ddb43f (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438 1 lock held by rsyslogd/8020: #0: 00000000415b1f7b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 2 locks held by getty/8143: #0: 000000001ff040f9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000c8fd0d49 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8144: #0: 00000000eefb39c7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000062bd4917 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8145: #0: 00000000dc519385 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000001ab64e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8146: #0: 00000000e9d9949f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000018fe8215 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8147: #0: 000000001799690b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000002ae07ac2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8148: #0: 0000000086e97c6a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000082868023 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 4 locks held by kworker/u4:2/3695: #0: 000000006f8b8724 ((wq_completion)"%s""netns"){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 000000006f8b8724 ((wq_completion)"%s""netns"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000006f8b8724 ((wq_completion)"%s""netns"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 000000006f8b8724 ((wq_completion)"%s""netns"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 000000006f8b8724 ((wq_completion)"%s""netns"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 000000006f8b8724 ((wq_completion)"%s""netns"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 000000006f8b8724 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124 #1: 00000000857927ae (net_cleanup_work){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128 #2: 00000000cebb82b7 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0x960 net/core/net_namespace.c:520 #3: 00000000a2fed0d7 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 3 locks held by kworker/u4:4/15133: 2 locks held by getty/18310: #0: 00000000dfc4e73b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000a9c9f1d0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 1 lock held by syz-executor.3/18603: #0: 00000000cebb82b7 (pernet_ops_rwsem){++++}, at: register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1643 1 lock held by syz-executor.3/18608: #0: 00000000cebb82b7 (pernet_ops_rwsem){++++}, at: register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1643 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1077 Comm: khungtaskd Not tainted 4.19.95-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+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 10 Comm: rcu_preempt Not tainted 4.19.95-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lockdep_hardirqs_on+0x31d/0x5d0 kernel/locking/lockdep.c:2868 Code: 00 00 00 00 fc ff df 48 89 da 83 e3 07 48 c1 ea 03 83 c3 03 0f b6 04 02 38 c3 7c 08 84 c0 0f 85 d1 01 00 00 8b 3d 33 e6 77 09 <85> ff 0f 85 ed fd ff ff 48 c7 c0 88 c9 cd 89 48 ba 00 00 00 00 00 RSP: 0018:ffff8880aa37fa18 EFLAGS: 00000097 RAX: 0000000000000004 RBX: 0000000000000003 RCX: 1ffffffff1279058 RDX: 1ffffffff1594754 RSI: ffffffff8170517e RDI: 0000000000000000 RBP: ffff8880aa37fa28 R08: ffff8880aa36c280 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8755e7c8 R13: ffffffff8148da06 R14: ffffffff8755e7c8 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000045af1f CR3: 0000000095b41000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_hardirqs_on+0x67/0x220 kernel/trace/trace_preemptirq.c:30 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] _raw_spin_unlock_irq+0x28/0x90 kernel/locking/spinlock.c:192 finish_lock_switch kernel/sched/core.c:2576 [inline] finish_task_switch+0x146/0x7c0 kernel/sched/core.c:2676 context_switch kernel/sched/core.c:2829 [inline] __schedule+0x86e/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 schedule_timeout+0x4db/0xfc0 kernel/time/timer.c:1806 rcu_gp_kthread+0xd5c/0x2190 kernel/rcu/tree.c:2202 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415