INFO: task syz-executor.0:11339 can't die for more than 143 seconds. task:syz-executor.0 state:D stack:27632 pid:11339 ppid: 4581 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8cd/0x2150 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 schedule_timeout+0x1d8/0x250 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+0x163/0x260 kernel/sched/completion.c:138 __flush_work+0x51f/0xac0 kernel/workqueue.c:3052 __cancel_work_timer+0x3b3/0x520 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/0x360 net/9p/client.c:1088 v9fs_session_init+0xfd2/0x1770 fs/9p/v9fs.c:482 v9fs_mount+0x79/0x9b0 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1496 do_new_mount fs/namespace.c:2899 [inline] path_mount+0x12ae/0x1e70 fs/namespace.c:3230 do_mount fs/namespace.c:3243 [inline] __do_sys_mount fs/namespace.c:3451 [inline] __se_sys_mount fs/namespace.c:3428 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3428 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 RSP: 002b:00007f4e239edc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 000000000119c078 R08: 0000000020000580 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034 R13: 00007ffd28c0128f R14: 00007f4e239ee9c0 R15: 000000000119c034 INFO: task syz-executor.0:11339 blocked for more than 143 seconds. Not tainted 5.10.0-next-20201223-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:27632 pid:11339 ppid: 4581 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8cd/0x2150 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 schedule_timeout+0x1d8/0x250 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+0x163/0x260 kernel/sched/completion.c:138 __flush_work+0x51f/0xac0 kernel/workqueue.c:3052 __cancel_work_timer+0x3b3/0x520 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/0x360 net/9p/client.c:1088 v9fs_session_init+0xfd2/0x1770 fs/9p/v9fs.c:482 v9fs_mount+0x79/0x9b0 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1496 do_new_mount fs/namespace.c:2899 [inline] path_mount+0x12ae/0x1e70 fs/namespace.c:3230 do_mount fs/namespace.c:3243 [inline] __do_sys_mount fs/namespace.c:3451 [inline] __se_sys_mount fs/namespace.c:3428 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3428 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 RSP: 002b:00007f4e239edc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 000000000119c078 R08: 0000000020000580 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034 R13: 00007ffd28c0128f R14: 00007f4e239ee9c0 R15: 000000000119c034 Showing all locks held in the system: 1 lock held by khungtaskd/1660: #0: ffffffff8b363660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8168: #0: ffff88801bf43c70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:949 2 locks held by kworker/1:8/7885: #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010062d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2246 #1: ffffc90002d3fda8 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2250 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1660 Comm: khungtaskd Not tainted 5.10.0-next-20201223-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+0x107/0x163 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:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd89/0xf30 kernel/hung_task.c:338 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4889 Comm: systemd-journal Not tainted 5.10.0-next-20201223-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:apparmor_file_permission+0xd8/0x4e0 security/apparmor/include/cred.h:27 Code: bb 88 00 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 7d 03 00 00 48 63 2d 25 ea 59 07 48 03 ab 88 00 00 00 0f 84 a0 02 00 00 d3 48 e7 fd 48 89 ea 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 RSP: 0018:ffffc9000130fdb8 EFLAGS: 00000286 RAX: dffffc0000000000 RBX: ffff88801182a300 RCX: 0000000000000000 RDX: 1ffff11002305471 RSI: ffffffff838b307b RDI: ffff88801182a388 RBP: ffff88801170bb90 R08: 0000000000000000 R09: ffff888025dcc783 R10: ffffffff81bff436 R11: 0000000000000000 R12: ffff888011e8d680 R13: 0000000000000004 R14: dffffc0000000000 R15: 0000000000000001 FS: 00007f7e381a28c0(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff99c015a70 CR3: 0000000011134000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: security_file_permission+0x56/0x560 security/security.c:1448 rw_verify_area+0x115/0x350 fs/read_write.c:400 vfs_read+0x126/0x570 fs/read_write.c:487 ksys_read+0x12d/0x250 fs/read_write.c:634 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f7e3773222d Code: c1 20 00 00 75 10 b8 00 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24 b8 00 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 97 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007fff4db6edc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fff4db71840 RCX: 00007f7e3773222d RDX: 0000000000002000 RSI: 00007fff4db6f640 RDI: 0000000000000009 RBP: 0000000000000000 R08: 0000000000000008 R09: 00007fff4dbbd0f0 R10: 00000000000a2e8e R11: 0000000000000293 R12: 00007fff4db6f640 R13: 00007fff4db71798 R14: 00005584d17c3958 R15: 0005b7f947512630