INFO: task kworker/u4:9:5316 blocked for more than 143 seconds. Not tainted 6.8.0-rc2-next-20240202-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:9 state:D stack:22104 pid:5316 tgid:5316 ppid:2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17df/0x4a40 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6804 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6819 schedule_timeout+0xb0/0x310 kernel/time/timer.c:2159 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x355/0x620 kernel/sched/completion.c:148 __flush_workqueue+0x730/0x1630 kernel/workqueue.c:3617 drain_workqueue+0xc9/0x390 kernel/workqueue.c:3730 destroy_workqueue+0xba/0xc40 kernel/workqueue.c:5319 bond_destructor+0x4d/0x80 drivers/net/bonding/bond_main.c:5846 netdev_run_todo+0xd4f/0xf40 net/core/dev.c:10581 default_device_exit_batch+0x975/0x9f0 net/core/dev.c:11625 ops_exit_list net/core/net_namespace.c:175 [inline] cleanup_net+0x775/0xb90 net/core/net_namespace.c:618 process_one_work kernel/workqueue.c:3049 [inline] process_scheduled_works+0x913/0x14f0 kernel/workqueue.c:3125 worker_thread+0xa60/0x1000 kernel/workqueue.c:3206 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 2 locks held by kworker/u4:6/2473: 2 locks held by kworker/u4:8/2797: 2 locks held by getty/4823: #0: ffff88802a4b60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201 4 locks held by syz-executor.3/5108: 3 locks held by kworker/0:6/5153: #0: ffff8880b943c758 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 #1: ffff8880b9428988 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 #2: ffff8880b943c758 (&rq->__lock){-.-.}-{2:2}, at: finish_lock_switch kernel/sched/core.c:5152 [inline] #2: ffff8880b943c758 (&rq->__lock){-.-.}-{2:2}, at: finish_task_switch+0x1b2/0x870 kernel/sched/core.c:5272 3 locks held by kworker/u4:9/5316: #0: ffff888015acd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline] #0: ffff888015acd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125 #1: ffffc90004bb7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline] #1: ffffc90004bb7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125 #2: ffffffff8f36da50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf5/0xb90 net/core/net_namespace.c:580 4 locks held by syz-executor.1/8096: 2 locks held by kworker/u4:10/8244: 1 lock held by syz-executor.4/8493: 3 locks held by syz-executor.0/10715: #0: ffff88802cc56420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write_file+0x61/0x200 fs/namespace.c:453 #1: ffff88808428c000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #1: ffff88808428c000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_fileattr_set+0x139/0xd50 fs/ioctl.c:682 #2: ffff88802cc58b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_write fs/ext4/ext4.h:1779 [inline] #2: ffff88802cc58b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ind_migrate+0x26a/0x8d0 fs/ext4/migrate.c:625 2 locks held by syz-executor.0/10720: #0: ffff88802cc56420 (sb_writers#4){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2801 [inline] #0: ffff88802cc56420 (sb_writers#4){.+.+}-{0:0}, at: vfs_writev+0x2d9/0xbb0 fs/read_write.c:969 #1: ffff88808428c000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #1: ffff88808428c000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_dio_write_iter fs/ext4/file.c:530 [inline] #1: ffff88808428c000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_file_write_iter+0x388/0x1a10 fs/ext4/file.c:696 4 locks held by syz-executor.2/10713: #0: ffff88802cc56420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write_file+0x61/0x200 fs/namespace.c:453 #1: ffff888080baa200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #1: ffff888080baa200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_fileattr_set+0x139/0xd50 fs/ioctl.c:682 #2: ffff88802cc58b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_write fs/ext4/ext4.h:1779 [inline] #2: ffff88802cc58b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ind_migrate+0x26a/0x8d0 fs/ext4/migrate.c:625 #3: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #3: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x39a/0x820 kernel/rcu/tree_exp.h:939 2 locks held by syz-executor.2/10716: #0: ffff88802cc56420 (sb_writers#4){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2801 [inline] #0: ffff88802cc56420 (sb_writers#4){.+.+}-{0:0}, at: vfs_writev+0x2d9/0xbb0 fs/read_write.c:969 #1: ffff888080baa200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #1: ffff888080baa200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_dio_write_iter fs/ext4/file.c:530 [inline] #1: ffff888080baa200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_file_write_iter+0x388/0x1a10 fs/ext4/file.c:696 3 locks held by syz-executor.3/10721: #0: ffff88802cc56420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write_file+0x61/0x200 fs/namespace.c:453 #1: ffff88806ad0e800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #1: ffff88806ad0e800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_fileattr_set+0x139/0xd50 fs/ioctl.c:682 #2: ffff88802cc58b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_write fs/ext4/ext4.h:1779 [inline] #2: ffff88802cc58b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ind_migrate+0x26a/0x8d0 fs/ext4/migrate.c:625 2 locks held by syz-executor.3/10723: #0: ffff88802cc56420 (sb_writers#4){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2801 [inline] #0: ffff88802cc56420 (sb_writers#4){.+.+}-{0:0}, at: vfs_writev+0x2d9/0xbb0 fs/read_write.c:969 #1: ffff88806ad0e800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #1: ffff88806ad0e800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_dio_write_iter fs/ext4/file.c:530 [inline] #1: ffff88806ad0e800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_file_write_iter+0x388/0x1a10 fs/ext4/file.c:696 5 locks held by syz-executor.4/10740: 1 lock held by syz-executor.1/10737: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc2-next-20240202-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfb0/0xff0 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 10740 Comm: syz-executor.4 Not tainted 6.8.0-rc2-next-20240202-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:rcu_is_watching+0x1c/0xb0 kernel/rcu/tree.c:700 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 65 ff 05 38 92 88 7e e8 4b bc f1 09 89 c3 83 f8 08 73 7a <49> bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 40 99 ae 8d 4c 89 f0 48 RSP: 0018:ffffc90012adf500 EFLAGS: 00000093 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff819afd8c RDX: 0000000000000000 RSI: ffffffff8bfe7a40 RDI: ffffffff8bfe7a00 RBP: ffffc90012adf5d0 R08: ffffffff8f85b72f R09: 1ffffffff1f0b6e5 R10: dffffc0000000000 R11: fffffbfff1f0b6e6 R12: dffffc0000000000 R13: 1ffff9200255bea8 R14: ffffc90012adf560 R15: 0000000000000246 FS: 00007f97a93ad6c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000202d1030 CR3: 000000002c802000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_irq_enable+0x3b/0x100 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:56 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x8f/0x140 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __skb_try_recv_datagram+0x1cb/0x6a0 net/core/datagram.c:266 __unix_dgram_recvmsg+0x3ce/0x1450 net/unix/af_unix.c:2442 sock_recvmsg_nosec+0x18e/0x1d0 net/socket.c:1046 ____sys_recvmsg+0x3c0/0x470 net/socket.c:2801 ___sys_recvmsg net/socket.c:2845 [inline] do_recvmmsg+0x474/0xae0 net/socket.c:2939 __sys_recvmmsg net/socket.c:3018 [inline] __do_sys_recvmmsg net/socket.c:3041 [inline] __se_sys_recvmmsg net/socket.c:3034 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3034 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f97a867dda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f97a93ad0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f97a87ac050 RCX: 00007f97a867dda9 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007f97a86ca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f97a87ac050 R15: 00007ffda3456938