INFO: task syz-executor.0:1683 blocked for more than 143 seconds. Not tainted 5.12.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:23952 pid: 1683 ppid: 11332 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4322 [inline] __schedule+0x911/0x21b0 kernel/sched/core.c:5073 schedule+0xcf/0x270 kernel/sched/core.c:5152 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1407 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1949 raw_release+0x58/0x8a0 net/can/raw.c:354 __sock_release+0xcd/0x280 net/socket.c:599 sock_close+0x18/0x20 net/socket.c:1258 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:140 exit_task_work include/linux/task_work.h:30 [inline] do_exit+0xbfc/0x2a60 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2150 kernel/signal.c:2781 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 RSP: 002b:00007f5d6726d188 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000004 RBX: 000000000056c008 RCX: 00000000004665f9 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffc264ae92f R14: 00007f5d6726d300 R15: 0000000000022000 Showing all locks held in the system: 2 locks held by kworker/u4:0/9: 3 locks held by kworker/u4:7/758: #0: ffff8880116d3138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880116d3138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880116d3138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880116d3138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880116d3138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880116d3138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc9000371fda8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 #2: ffffffff8d65fb90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:557 1 lock held by khungtaskd/1632: #0: ffffffff8bf74520 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6328 1 lock held by in:imklog/8098: #0: ffff88801499c370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 2 locks held by syz-executor.0/1683: #0: ffff888065ff11d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline] #0: ffff888065ff11d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:598 #1: ffffffff8d65fb90 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1949 1 lock held by syz-executor.0/2221: #0: ffffffff8d65fb90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:470 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1632 Comm: khungtaskd Not tainted 5.12.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 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+0xd48/0xfb0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4815 Comm: systemd-journal Not tainted 5.12.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x7/0x60 kernel/kcov.c:197 Code: ff ff b9 ff ff ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 40 00 65 8b 05 59 f9 8d 7e <89> c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 00 f0 01 00 a9 RSP: 0018:ffffc9000166f8a8 EFLAGS: 00000002 RAX: 0000000080000001 RBX: 0000000000000002 RCX: 0000000000000003 RDX: 0000000000000000 RSI: ffff888024b01c40 RDI: 0000000000000003 RBP: ffffc9000166fa18 R08: 0000000000000001 R09: ffffc9000166fa1f R10: ffffffff815c5d64 R11: 0000000000000000 R12: 1ffff920002cdf16 R13: 0000000000001d89 R14: 0000000000000003 R15: dffffc0000000000 FS: 00007fdabfc598c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa1bc032001 CR3: 0000000025b4a000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: desc_read_finalized_seq+0xa3/0x1c0 kernel/printk/printk_ringbuffer.c:1760 prb_read kernel/printk/printk_ringbuffer.c:1800 [inline] _prb_read_valid+0x1cd/0x710 kernel/printk/printk_ringbuffer.c:1880 prb_read_valid_info+0xa7/0xe0 kernel/printk/printk_ringbuffer.c:1963 devkmsg_poll+0x14d/0x260 kernel/printk/printk.c:824 vfs_poll include/linux/poll.h:90 [inline] ep_item_poll+0xf4/0x190 fs/eventpoll.c:840 ep_send_events fs/eventpoll.c:1677 [inline] ep_poll fs/eventpoll.c:1792 [inline] do_epoll_wait+0x724/0x1920 fs/eventpoll.c:2220 __do_sys_epoll_wait fs/eventpoll.c:2232 [inline] __se_sys_epoll_wait fs/eventpoll.c:2227 [inline] __x64_sys_epoll_wait+0x158/0x270 fs/eventpoll.c:2227 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fdabef222e3 Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 83 3d 29 54 2b 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 0b c2 00 00 48 89 04 24 RSP: 002b:00007ffc6dfdf238 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 000055ac6ef2a1e0 RCX: 00007fdabef222e3 RDX: 0000000000000013 RSI: 00007ffc6dfdf240 RDI: 0000000000000008 RBP: 00007ffc6dfdf430 R08: 000055ac6ef2c870 R09: 00007ffc6dfef080 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc6dfdf240 R13: 0000000000000001 R14: 0000000000000000 R15: 0005c1a15849624d