INFO: tas
INFO: task syz.7.3826:15173 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.3826      state:D stack:28360 pid:15173 tgid:15172 ppid:12388  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17db/0x58f0
 schedule+0x164/0x2b0
 cgroup_lock_and_drain_offline+0x51a/0x650
 cgroup1_get_tree+0x9d/0x890
 vfs_get_tree+0x92/0x2a0
 do_new_mount+0x319/0xdc0
 __se_sys_mount+0x31d/0x420
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0c0359e159
RSP: 002b:00007f0c04489028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f0c03825fa0 RCX: 00007f0c0359e159
RDX: 00002000000001c0 RSI: 0000200000000100 RDI: 0000000000000000
RBP: 00007f0c03635024 R08: 0000200000000040 R09: 0000000000000000
R10: 0000000000000848 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0c03826038 R14: 00007f0c03825fa0 R15: 00007ffdbb3a4508
 </TASK>
INFO: task syz.9.3842:15212 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.3842      state:D stack:28808 pid:15212 tgid:15211 ppid:14088  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17db/0x58f0
 schedule+0x164/0x2b0
 cgroup_lock_and_drain_offline+0x51a/0x650
 cgroup1_get_tree+0x9d/0x890
 vfs_get_tree+0x92/0x2a0
 do_new_mount+0x319/0xdc0
 __se_sys_mount+0x31d/0x420
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb4ef19e159
RSP: 002b:00007fb4effb1028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb4ef425fa0 RCX: 00007fb4ef19e159
RDX: 00002000000000c0 RSI: 0000200000000000 RDI: 0000000000000000
RBP: 00007fb4ef235024 R08: 00002000000001c0 R09: 0000000000000000
R10: 0000000000010012 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb4ef426038 R14: 00007fb4ef425fa0 R15: 00007ffe67ace7e8
 </TASK>

Showing all locks held in the system:
locks held by khungtaskd/35: 1, last CPU#1:
 #0: ffffffff8ed5cbe0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
locks held by getty/5423: 2, on CPU#1:
 #0: ffff888102ac90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034762e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360
locks held by syz.8.3182/13646: 1, last CPU#0:
 #0: ffff888175f64cc0 (&ima_iint_mutex_key[depth]#2){+.+.}-{4:4}, at: process_measurement+0x7d0/0x1c10
locks held by udevd/16074: 3, last CPU#0:
 #0: ffff88801d280168 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x7d0/0x1c10
 #1: ffffffff8f4f3f78 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_check_open_permission+0x1d3/0x470
 #2: ffffffff8ed5cbe0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550
locks held by syz-executor/16135: 6, last CPU#0:
 #0: ffff888112a7e0e8 (&type->s_umount_key#33){++++}-{4:4}, at: deactivate_super+0xac/0xe0
 #1: ffff888105b803c8 (&sbi->s_error_notify_mutex){+.+.}-{4:4}, at: ext4_unregister_sysfs+0x93/0xc0
 #2: ffff8881012d42a0 (&root->kernfs_supers_rwsem){++++}-{4:4}, at: kernfs_remove_by_name_ns+0x3f/0x140
 #3: ffff8881012d4180 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_remove_by_name_ns+0x4e/0x140
 #4: ffff8881012d4210 (&root->kernfs_iattr_rwsem){++++}-{4:4}, at: __kernfs_remove+0x4f6/0x8e0
 #5: ffffffff8ed5cbe0 (rcu_read_lock){....}-{1:3}, at: kernfs_root+0x1c/0x230
locks held by syz.5.5513/19748: 1, last CPU#0:
 #0: ffff88811dd300e8 (&type->s_umount_key#73/1){+.+.}-{4:4}, at: sget_fc+0x97c/0x1a40

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17d/0x390
 sys_info+0x135/0x170
 watchdog+0xfd7/0x1030
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16 Comm: pr/ttyS0 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:io_serial_out+0x7c/0xc0
Code: 47 54 fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 1c 84 c4 fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc cc 44 89 f9 80 e1 07 38 c1
RSP: 0018:ffffc90000157900 EFLAGS: 00000002
RAX: 0000000000000035 RBX: 0000000000000035 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 00000000000003f8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff857371f0 R12: dffffc0000000000
R13: 0000000000000035 R14: ffffffff9ad3f0c0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88818d6cc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005598200dd298 CR3: 000000011dc82000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __serial8250_console_fifo_write+0x1e6/0x3e0
 serial8250_console_write+0xaa1/0x1200
 nbcon_emit_next_record+0xef5/0x1a90
 nbcon_kthread_func+0x679/0x880
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
