INFO: task syz-executor.1:10071 can't die for more than 143 seconds. task:syz-executor.1 state:D stack:27536 pid:10071 ppid: 8455 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4329 [inline] __schedule+0x917/0x2170 kernel/sched/core.c:5079 schedule+0xcf/0x270 kernel/sched/core.c:5158 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+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x466459 RSP: 002b:00007fce7dac2188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000466459 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 00000000004bf9fb R08: 0000000020000180 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffe72d979ef R14: 00007fce7dac2300 R15: 0000000000022000 INFO: task syz-executor.1:10071 blocked for more than 143 seconds. Not tainted 5.12.0-rc7-next-20210415-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:27536 pid:10071 ppid: 8455 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4329 [inline] __schedule+0x917/0x2170 kernel/sched/core.c:5079 schedule+0xcf/0x270 kernel/sched/core.c:5158 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+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x466459 RSP: 002b:00007fce7dac2188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000466459 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 00000000004bf9fb R08: 0000000020000180 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffe72d979ef R14: 00007fce7dac2300 R15: 0000000000022000 Showing all locks held in the system: 2 locks held by kworker/u4:5/263: 1 lock held by khungtaskd/1650: #0: ffffffff8bf76560 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6333 1 lock held by in:imklog/8146: 2 locks held by kworker/1:6/9763: #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc90016367da8 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1650 Comm: khungtaskd Not tainted 5.12.0-rc7-next-20210415-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:253 [inline] watchdog+0xd3b/0xf50 kernel/hung_task.c:338 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: 4859 Comm: systemd-journal Not tainted 5.12.0-rc7-next-20210415-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:account_steal_time kernel/sched/cputime.c:210 [inline] RIP: 0010:steal_account_process_time kernel/sched/cputime.c:244 [inline] RIP: 0010:account_other_time kernel/sched/cputime.c:262 [inline] RIP: 0010:get_vtime_delta+0x1c7/0x420 kernel/sched/cputime.c:656 Code: c0 89 c0 41 83 f8 07 0f 87 b2 01 00 00 48 8d 3c c5 e0 26 0d 8b 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 11 00 <0f> 85 db 01 00 00 4c 03 3c c5 e0 26 0d 8b 48 b8 00 00 00 00 00 fc RSP: 0018:ffffc9000162fe98 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff8880126c5c30 RCX: 1ffffffff161a4dc RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff8b0d26e0 RBP: 000000000000180b R08: 0000000000000000 R09: ffffffff8f3e400f R10: ffffffff8f3e4017 R11: 0000000000000001 R12: ffff8880126c5c60 R13: 0000000000000000 R14: 0000000000035300 R15: 000000000001f780 FS: 00007fd3582ee8c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd35570a000 CR3: 0000000029bde000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vtime_user_exit+0xb4/0x210 kernel/sched/cputime.c:720 __context_tracking_exit+0xb8/0xe0 kernel/context_tracking.c:160 user_exit_irqoff include/linux/context_tracking.h:47 [inline] __enter_from_user_mode kernel/entry/common.c:21 [inline] syscall_enter_from_user_mode+0x55/0x70 kernel/entry/common.c:103 do_syscall_64+0x1c/0xb0 arch/x86/entry/common.c:42 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd357586f17 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:00007ffee3bb4778 EFLAGS: 00000206 ORIG_RAX: 0000000000000027 RAX: ffffffffffffffda RBX: 000055c5de7f01e0 RCX: 00007fd357586f17 RDX: 00007ffee3bb4830 RSI: 0000000000000000 RDI: 000055c5de7f01e0 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000206 R12: 00007ffee3bb4830 R13: 00000000000012fb R14: 00007ffee3bb7620 R15: 00007ffee3bb4c30