INFO: task syz-executor.5:10742 can't die for more than 143 seconds. task:syz-executor.5 state:D stack:26712 pid:10742 ppid: 8839 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4688 [inline] __schedule+0xb38/0x58c0 kernel/sched/core.c:5945 schedule+0xcf/0x270 kernel/sched/core.c:6024 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1854 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x168/0x270 kernel/sched/completion.c:138 __flush_work+0x50e/0xad0 kernel/workqueue.c:3052 __cancel_work_timer+0x3f9/0x570 kernel/workqueue.c:3139 p9_conn_destroy net/9p/trans_fd.c:891 [inline] p9_fd_close+0x305/0x520 net/9p/trans_fd.c:921 p9_client_destroy+0xbe/0x370 net/9p/client.c:1088 v9fs_session_init+0xfc0/0x17b0 fs/9p/v9fs.c:482 v9fs_mount+0x79/0x9c0 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1498 do_new_mount fs/namespace.c:2905 [inline] path_mount+0x132a/0x1fa0 fs/namespace.c:3235 do_mount fs/namespace.c:3248 [inline] __do_sys_mount fs/namespace.c:3456 [inline] __se_sys_mount fs/namespace.c:3433 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3433 do_syscall_64+0x31/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665d9 RSP: 002b:00007f956a37a188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665d9 RDX: 00000000200001c0 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 00000000004bfcb9 R08: 00000000200003c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffcc46d9b7f R14: 00007f956a37a300 R15: 0000000000022000 INFO: task syz-executor.5:10742 blocked for more than 143 seconds. Not tainted 5.13.0-rc2-next-20210518-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:26712 pid:10742 ppid: 8839 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4688 [inline] __schedule+0xb38/0x58c0 kernel/sched/core.c:5945 schedule+0xcf/0x270 kernel/sched/core.c:6024 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1854 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x168/0x270 kernel/sched/completion.c:138 __flush_work+0x50e/0xad0 kernel/workqueue.c:3052 __cancel_work_timer+0x3f9/0x570 kernel/workqueue.c:3139 p9_conn_destroy net/9p/trans_fd.c:891 [inline] p9_fd_close+0x305/0x520 net/9p/trans_fd.c:921 p9_client_destroy+0xbe/0x370 net/9p/client.c:1088 v9fs_session_init+0xfc0/0x17b0 fs/9p/v9fs.c:482 v9fs_mount+0x79/0x9c0 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1498 do_new_mount fs/namespace.c:2905 [inline] path_mount+0x132a/0x1fa0 fs/namespace.c:3235 do_mount fs/namespace.c:3248 [inline] __do_sys_mount fs/namespace.c:3456 [inline] __se_sys_mount fs/namespace.c:3433 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3433 do_syscall_64+0x31/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665d9 RSP: 002b:00007f956a37a188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665d9 RDX: 00000000200001c0 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 00000000004bfcb9 R08: 00000000200003c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffcc46d9b7f R14: 00007f956a37a300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1649: #0: ffffffff8c17afe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6333 2 locks held by kworker/0:4/4021: #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc90004707da8 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 1 lock held by in:imklog/8172: #0: ffff88801d2c20f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by agetty/8380: #0: ffff888028d3b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:253 #1: ffffc90000fbc2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1649 Comm: khungtaskd Not tainted 5.13.0-rc2-next-20210518-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x13e/0x1d6 lib/dump_stack.c:129 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:254 [inline] watchdog+0xd3b/0xf50 kernel/hung_task.c:339 kthread+0x3b1/0x4a0 kernel/kthread.c:313 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: 4862 Comm: systemd-journal Not tainted 5.13.0-rc2-next-20210518-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__exit_to_user_mode kernel/entry/common.c:131 [inline] RIP: 0010:syscall_exit_to_user_mode+0x33/0x60 kernel/entry/common.c:303 Code: 9c 58 fa f6 c4 02 75 39 48 89 ef e8 47 9f 46 f8 e8 52 76 5e f8 48 8b 7c 24 08 e8 88 8e 3d f8 eb 14 66 90 0f 00 2d fd 18 70 00 <48> 8b 7c 24 08 5d e9 32 f6 ff ff bf 01 00 00 00 e8 08 03 00 00 eb RSP: 0018:ffffc90000edff30 EFLAGS: 000000d3 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802da11c80 RSI: ffffffff891d69f8 RDI: 0000000000000000 RBP: ffffc90000edff58 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffc90000edff58 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f228aa4a8c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2287e69000 CR3: 000000001d1cd000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: do_syscall_64+0x3e/0xb0 arch/x86/entry/common.c:57 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f2289ce2f17 Code: ff ff ff 48 8b 4d a0 0f b7 51 fe 48 8b 4d a8 66 89 54 08 fe e9 1a ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 b8 27 00 00 00 0f 05 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00 RSP: 002b:00007ffd3532b8b8 EFLAGS: 00000202 ORIG_RAX: 0000000000000027 RAX: 00000000000012fe RBX: 000055910d54b1e0 RCX: 00007f2289ce2f17 RDX: 00000000ffffffff RSI: 00007ffd3532b940 RDI: 000055910d54b1e0 RBP: 00000000000012fe R08: 0000000060a68896 R09: 00007ffd35394080 R10: 00007ffd35394080 R11: 0000000000000202 R12: 00007ffd3532b940 R13: 00007ffd3532b938 R14: 000055910c6be958 R15: 0005c2c519ae9b69