INFO: task syz-executor.5:11113 can't die for more than 143 seconds. task:syz-executor.5 state:D stack:28120 pid:11113 ppid: 6868 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4700 [inline] __schedule+0x949/0x2710 kernel/sched/core.c:5957 schedule+0xd3/0x290 kernel/sched/core.c:6036 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 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+0x176/0x280 kernel/sched/completion.c:138 __flush_work+0x50e/0xad0 kernel/workqueue.c:3053 __cancel_work_timer+0x3f9/0x570 kernel/workqueue.c:3140 p9_conn_destroy net/9p/trans_fd.c:891 [inline] p9_fd_close+0x305/0x520 net/9p/trans_fd.c:921 p9_client_create+0x95a/0x1110 net/9p/client.c:1071 v9fs_session_init+0x1dd/0x17b0 fs/9p/v9fs.c:406 v9fs_mount+0x79/0x9c0 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1498 do_new_mount fs/namespace.c:2978 [inline] path_mount+0x132a/0x1fa0 fs/namespace.c:3308 do_mount fs/namespace.c:3321 [inline] __do_sys_mount fs/namespace.c:3529 [inline] __se_sys_mount fs/namespace.c:3506 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3506 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 RSP: 002b:00007f7a53ee8188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665e9 RDX: 0000000020000080 RSI: 0000000020000300 RDI: 0000000000000000 RBP: 00000000004bfcc4 R08: 0000000020001e80 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffc2bc9cc3f R14: 00007f7a53ee8300 R15: 0000000000022000 INFO: task syz-executor.5:11113 blocked for more than 143 seconds. Not tainted 5.14.0-rc3-next-20210729-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:28120 pid:11113 ppid: 6868 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4700 [inline] __schedule+0x949/0x2710 kernel/sched/core.c:5957 schedule+0xd3/0x290 kernel/sched/core.c:6036 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 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+0x176/0x280 kernel/sched/completion.c:138 __flush_work+0x50e/0xad0 kernel/workqueue.c:3053 __cancel_work_timer+0x3f9/0x570 kernel/workqueue.c:3140 p9_conn_destroy net/9p/trans_fd.c:891 [inline] p9_fd_close+0x305/0x520 net/9p/trans_fd.c:921 p9_client_create+0x95a/0x1110 net/9p/client.c:1071 v9fs_session_init+0x1dd/0x17b0 fs/9p/v9fs.c:406 v9fs_mount+0x79/0x9c0 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1498 do_new_mount fs/namespace.c:2978 [inline] path_mount+0x132a/0x1fa0 fs/namespace.c:3308 do_mount fs/namespace.c:3321 [inline] __do_sys_mount fs/namespace.c:3529 [inline] __se_sys_mount fs/namespace.c:3506 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3506 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 RSP: 002b:00007f7a53ee8188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665e9 RDX: 0000000020000080 RSI: 0000000020000300 RDI: 0000000000000000 RBP: 00000000004bfcc4 R08: 0000000020001e80 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffc2bc9cc3f R14: 00007f7a53ee8300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8b97e8c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/6273: #0: ffff888073b54d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by kworker/0:9/8600: #0: ffff888010864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010864d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:617 [inline] #0: ffff888010864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: ffff888010864d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x1630 kernel/workqueue.c:2247 #1: ffffc900173c7db0 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1630 kernel/workqueue.c:2251 3 locks held by kworker/u4:16/11202: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.14.0-rc3-next-20210729-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+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x28/0x11b lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 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+0xd3e/0xf50 kernel/hung_task.c:339 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2972 Comm: systemd-journal Not tainted 5.14.0-rc3-next-20210729-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:write_comp_data kernel/kcov.c:217 [inline] RIP: 0010:__sanitizer_cov_trace_cmp8+0xf/0x70 kernel/kcov.c:264 Code: 44 38 e0 07 00 00 00 48 89 4c 38 f0 4e 89 54 c8 20 48 89 10 c3 66 0f 1f 44 00 00 49 89 f8 bf 03 00 00 00 4c 8b 14 24 48 89 f1 <65> 48 8b 34 25 00 f0 01 00 e8 c3 f1 ff ff 84 c0 74 48 48 8b 86 20 RSP: 0018:ffffc90002bafa88 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: ffffffff8b94edd0 RCX: 00000000ffffeb56 RDX: 1ffffffff1729dba RSI: 00000000ffffeb56 RDI: 0000000000000003 RBP: ffffc90002bafc48 R08: 00000000ffffeb56 R09: ffffffff8b94edd7 R10: ffffffff815d9090 R11: 0000000000004000 R12: 00000000ffffeb56 R13: 80000000ffffeb56 R14: 00000000ffffeb56 R15: ffffffff8b8cc330 FS: 00007f9c9c7c78c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9c99c10000 CR3: 000000001a103000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: get_desc_state kernel/printk/printk_ringbuffer.c:417 [inline] desc_read+0x110/0x350 kernel/printk/printk_ringbuffer.c:444 desc_read_finalized_seq+0x81/0x1c0 kernel/printk/printk_ringbuffer.c:1752 prb_read kernel/printk/printk_ringbuffer.c:1800 [inline] _prb_read_valid+0x1cd/0x710 kernel/printk/printk_ringbuffer.c:1880 prb_read_valid+0x75/0xa0 kernel/printk/printk_ringbuffer.c:1929 devkmsg_read+0x165/0x730 kernel/printk/printk.c:733 vfs_read+0x1b5/0x570 fs/read_write.c:494 ksys_read+0x12d/0x250 fs/read_write.c:634 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f9c9bd56210 Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 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 RSP: 002b:00007ffe64cc37e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007ffe64cc6260 RCX: 00007f9c9bd56210 RDX: 0000000000002000 RSI: 00007ffe64cc4060 RDI: 0000000000000009 RBP: 0000000000000000 R08: 0000000000000008 R09: 00007ffe64cd4080 R10: 00007ffe64cd40f0 R11: 0000000000000246 R12: 00007ffe64cc4060 R13: 00007ffe64cc61b8 R14: 00005578f05c6958 R15: 0005c8579d7077f2