INFO: task syz-executor.4:25352 can't die for more than 143 seconds. task:syz-executor.4 state:D stack:27312 pid:25352 ppid: 8536 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8eb/0x21b0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x809/0x1220 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2214 do_new_mount_fc fs/namespace.c:2842 [inline] do_new_mount fs/namespace.c:2901 [inline] path_mount+0x1678/0x1e70 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: 0033:0x45e149 RSP: 002b:00007f8facd3ec68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e149 RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007fff3407650f R14: 00007f8facd3f9c0 R15: 000000000119bf8c INFO: task syz-executor.4:25352 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.4 state:D stack:27312 pid:25352 ppid: 8536 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8eb/0x21b0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x809/0x1220 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2214 do_new_mount_fc fs/namespace.c:2842 [inline] do_new_mount fs/namespace.c:2901 [inline] path_mount+0x1678/0x1e70 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: 0033:0x45e149 RSP: 002b:00007f8facd3ec68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e149 RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007fff3407650f R14: 00007f8facd3f9c0 R15: 000000000119bf8c INFO: task syz-executor.4:25357 can't die for more than 144 seconds. task:syz-executor.4 state:R running task stack:27056 pid:25357 ppid: 8536 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8eb/0x21b0 kernel/sched/core.c:5078 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:5238 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:40 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:394 [inline] ilookup5_nowait fs/inode.c:1335 [inline] ilookup5 fs/inode.c:1363 [inline] iget5_locked+0xcc/0x2d0 fs/inode.c:1144 fuse_iget+0x271/0x610 fs/fuse/inode.c:342 fuse_lookup_name+0x447/0x630 fs/fuse/dir.c:439 fuse_lookup.part.0+0xdf/0x390 fs/fuse/dir.c:469 fuse_lookup fs/fuse/dir.c:465 [inline] fuse_atomic_open+0x2de/0x440 fs/fuse/dir.c:621 atomic_open fs/namei.c:2972 [inline] lookup_open.isra.0+0xc3d/0x13d0 fs/namei.c:3078 open_last_lookups fs/namei.c:3180 [inline] path_openat+0x9af/0x27a0 fs/namei.c:3368 do_filp_open+0x17e/0x3c0 fs/namei.c:3398 do_sys_openat2+0x16d/0x420 fs/open.c:1172 do_sys_open fs/open.c:1188 [inline] __do_sys_openat fs/open.c:1204 [inline] __se_sys_openat fs/open.c:1199 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1199 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e149 RSP: 002b:00007f8facd1dc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045e149 RDX: 0000000000000000 RSI: 0000000020002040 RDI: ffffffffffffff9c RBP: 000000000119c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034 R13: 00007fff3407650f R14: 00007f8facd1e9c0 R15: 000000000119c034 Showing all locks held in the system: 3 locks held by kworker/u4:3/150: 1 lock held by khungtaskd/1636: #0: ffffffff8b793ae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x28c kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8319: #0: ffff8880255fd9f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:949 2 locks held by kworker/u4:0/8591: 2 locks held by kworker/0:10/13289: #0: ffff8880b9c34c58 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1318 [inline] #0: ffff8880b9c34c58 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x235/0x21b0 kernel/sched/core.c:4995 #1: ffff8880b9c20088 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x305/0x440 kernel/sched/psi.c:833 1 lock held by syz-executor.4/25352: #0: ffff8880aa9b8150 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff8880aa9b8150 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2214 2 locks held by syz-executor.4/25357: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1636 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+0x3c/0xef 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+0xe75/0x1020 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4894 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:__sanitizer_cov_trace_pc+0x37/0x60 kernel/kcov.c:197 Code: 81 e1 00 01 00 00 65 48 8b 14 25 00 f0 01 00 a9 00 01 ff 00 74 0e 85 c9 74 35 8b 82 d4 14 00 00 85 c0 74 2b 8b 82 b0 14 00 00 <83> f8 02 75 20 48 8b 8a b8 14 00 00 8b 92 b4 14 00 00 48 8b 01 48 RSP: 0018:ffffc900015cfa90 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffffff8b7735e0 RCX: 0000000000000000 RDX: ffff8880265b8000 RSI: ffffffff815b9ecf RDI: ffffc900015cfc68 RBP: ffffc900015cfc50 R08: 0000000000000001 R09: ffffc900015cfc67 R10: fffff520002b9f8c R11: 0000000000000001 R12: 00000000fffff784 R13: 0000000000001784 R14: 0000000000000002 R15: ffffffff8b7216c0 FS: 00007f02f256e8c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f02efb5d028 CR3: 0000000025aee000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: desc_read+0x1af/0x350 kernel/printk/printk_ringbuffer.c:481 desc_read_finalized_seq+0x81/0x1c0 kernel/printk/printk_ringbuffer.c:1752 prb_read kernel/printk/printk_ringbuffer.c:1820 [inline] _prb_read_valid+0x4a6/0x700 kernel/printk/printk_ringbuffer.c:1880 prb_read_valid+0x75/0xa0 kernel/printk/printk_ringbuffer.c:1929 devkmsg_read+0x13f/0x740 kernel/printk/printk.c:723 vfs_read+0x1b5/0x570 fs/read_write.c:494 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: 0033:0x7f02f1afe210 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:00007ffee9339f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007ffee933c9f0 RCX: 00007f02f1afe210 RDX: 0000000000002000 RSI: 00007ffee933a7f0 RDI: 0000000000000009 RBP: 0000000000000000 R08: 0000000000000008 R09: 00007ffee93b40f0 R10: 000000000002f4a0 R11: 0000000000000246 R12: 00007ffee933a7f0 R13: 00007ffee933c948 R14: 000055578c600958 R15: 0005b72776682283