INFO: task syz-executor.0:10849 can't die for more than 143 seconds. task:syz-executor.0 state:D stack:26128 pid:10849 ppid: 8486 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:3773 [inline] __schedule+0x893/0x2130 kernel/sched/core.c:4522 schedule+0xcf/0x270 kernel/sched/core.c:4600 schedule_timeout+0x148/0x250 kernel/time/timer.c:1876 gfs2_gl_hash_clear+0x240/0x270 fs/gfs2/glock.c:1989 gfs2_fill_super+0x1e81/0x23f0 fs/gfs2/ops_fstype.c:1233 get_tree_bdev+0x421/0x740 fs/super.c:1344 gfs2_get_tree+0x4a/0x270 fs/gfs2/ops_fstype.c:1256 vfs_get_tree+0x89/0x2f0 fs/super.c:1549 do_new_mount fs/namespace.c:2896 [inline] path_mount+0x12ae/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x4608aa Code: Unable to access opcode bytes at RIP 0x460880. RSP: 002b:00007f14c8086a88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f14c8086b20 RCX: 00000000004608aa RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f14c8086ae0 RBP: 00007f14c8086ae0 R08: 00007f14c8086b20 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000 R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020047a20 INFO: task syz-executor.0:10849 blocked for more than 143 seconds. Not tainted 5.10.0-rc1-next-20201027-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:26128 pid:10849 ppid: 8486 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:3773 [inline] __schedule+0x893/0x2130 kernel/sched/core.c:4522 schedule+0xcf/0x270 kernel/sched/core.c:4600 schedule_timeout+0x148/0x250 kernel/time/timer.c:1876 gfs2_gl_hash_clear+0x240/0x270 fs/gfs2/glock.c:1989 gfs2_fill_super+0x1e81/0x23f0 fs/gfs2/ops_fstype.c:1233 get_tree_bdev+0x421/0x740 fs/super.c:1344 gfs2_get_tree+0x4a/0x270 fs/gfs2/ops_fstype.c:1256 vfs_get_tree+0x89/0x2f0 fs/super.c:1549 do_new_mount fs/namespace.c:2896 [inline] path_mount+0x12ae/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x4608aa Code: Unable to access opcode bytes at RIP 0x460880. RSP: 002b:00007f14c8086a88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f14c8086b20 RCX: 00000000004608aa RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f14c8086ae0 RBP: 00007f14c8086ae0 R08: 00007f14c8086b20 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000 R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020047a20 Showing all locks held in the system: 3 locks held by kworker/u4:2/30: 1 lock held by khungtaskd/1655: #0: ffffffff8b337d60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6259 1 lock held by in:imklog/8172: #0: ffff888016ea2370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:932 3 locks held by rs:main Q:Reg/8173: #0: ffff8880b9f34d18 (&rq->lock){-.-.}-{2:2}, at: newidle_balance+0x789/0xe50 kernel/sched/fair.c:10576 #1: ffffffff8b337d60 (rcu_read_lock){....}-{1:2}, at: cpu_of kernel/sched/sched.h:1072 [inline] #1: ffffffff8b337d60 (rcu_read_lock){....}-{1:2}, at: __update_idle_core+0x39/0x430 kernel/sched/fair.c:6018 #2: ffff88802e45a288 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline] #2: ffff88802e45a288 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: ext4_buffered_write_iter+0xb6/0x4d0 fs/ext4/file.c:264 1 lock held by syz-executor.0/10849: #0: ffff8880670e00e0 (&type->s_umount_key#62/1){+.+.}-{3:3}, at: alloc_super+0x201/0xaf0 fs/super.c:229 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1655 Comm: khungtaskd Not tainted 5.10.0-rc1-next-20201027-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:118 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:339 kthread+0x3af/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: 4894 Comm: systemd-journal Not tainted 5.10.0-rc1-next-20201027-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0x352/0x5590 kernel/locking/lockdep.c:4775 Code: fa 83 d8 ff 41 c1 e5 0f c1 e0 0d 41 c1 e7 10 45 0f b7 ed 44 09 e8 41 81 e7 00 00 03 00 41 c1 e1 13 41 09 c7 89 d8 48 c1 ea 03 e0 12 25 00 00 04 00 41 09 c7 8b 84 24 30 01 00 00 45 09 f9 c1 RSP: 0018:ffffc90000eef9b0 EFLAGS: 00000803 RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 1ffff110022d07c7 RSI: 0000000000000004 RDI: ffff888011683e3c RBP: ffff888011683e18 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888011683500 R13: 0000000000000000 R14: ffff8880110eb468 R15: 0000000000000000 FS: 00007fb7541b48c0(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb751673000 CR3: 00000000112ba000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5442 [inline] lock_acquire+0x1af/0x8b0 kernel/locking/lockdep.c:5407 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103 ep_send_events fs/eventpoll.c:1630 [inline] ep_poll fs/eventpoll.c:1857 [inline] do_epoll_wait+0xb39/0x1b70 fs/eventpoll.c:2213 __do_sys_epoll_wait fs/eventpoll.c:2223 [inline] __se_sys_epoll_wait fs/eventpoll.c:2220 [inline] __x64_sys_epoll_wait+0x93/0xf0 fs/eventpoll.c:2220 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fb75347e2e3 Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 83 3d 29 54 2b 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 0b c2 00 00 48 89 04 24 RSP: 002b:00007ffd8ae72018 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 0000561ed48aa1e0 RCX: 00007fb75347e2e3 RDX: 0000000000000013 RSI: 00007ffd8ae72020 RDI: 0000000000000008 RBP: 00007ffd8ae72210 R08: 0000561ed48b4440 R09: 00007ffd8ae8c080 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd8ae72020 R13: 0000000000000001 R14: ffffffffffffffff R15: 0005b2a24c48a452