INFO: task syz.4.46945:3826 blocked for more than 430 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.46945     state:D stack:0     pid:3826  tgid:3824  ppid:3083   task_flags:0x400140 flags:0x00000001
Call trace: 
[<81aeb24c>] (__schedule) from [<81aec660>] (__schedule_loop kernel/sched/core.c:6993 [inline])
[<81aeb24c>] (__schedule) from [<81aec660>] (schedule+0x2c/0x134 kernel/sched/core.c:7008)
 r10:8339cb00 r9:83f79000 r8:85e16a00 r7:851baa68 r6:85833400 r5:ebe95df8
 r4:847224c0
[<81aec634>] (schedule) from [<80769714>] (request_wait_answer fs/fuse/dev.c:585 [inline])
[<81aec634>] (schedule) from [<80769714>] (__fuse_request_send fs/fuse/dev.c:599 [inline])
[<81aec634>] (schedule) from [<80769714>] (__fuse_simple_request+0x398/0x4f4 fs/fuse/dev.c:693)
 r5:ebe95df8 r4:851baa10
[<8076937c>] (__fuse_simple_request) from [<8077a55c>] (fuse_simple_request fs/fuse/fuse_i.h:1263 [inline])
[<8076937c>] (__fuse_simple_request) from [<8077a55c>] (fuse_send_init+0xd8/0x134 fs/fuse/inode.c:1554)
 r8:85f1f240 r7:8077b68c r6:00000000 r5:85f6cb80 r4:85833400
[<8077a484>] (fuse_send_init) from [<8077b710>] (fuse_fill_super+0x84/0x90 fs/fuse/inode.c:1958)
 r5:8339cb00 r4:86130400
[<8077b68c>] (fuse_fill_super) from [<8057bb60>] (vfs_get_super fs/super.c:1327 [inline])
[<8077b68c>] (fuse_fill_super) from [<8057bb60>] (get_tree_nodev+0x60/0x90 fs/super.c:1346)
 r5:8339cb00 r4:86130400
[<8057bb00>] (get_tree_nodev) from [<80779e24>] (fuse_get_tree+0xdc/0x1c0 fs/fuse/inode.c:2027)
 r7:85e16a00 r6:85e693c0 r5:85f6cb80 r4:8339cb00
[<80779d48>] (fuse_get_tree) from [<80578c84>] (vfs_get_tree+0x2c/0x118 fs/super.c:1754)
 r7:00000000 r6:ebe95f6c r5:8339cb00 r4:00000049
[<80578c58>] (vfs_get_tree) from [<805a48f0>] (fc_mount+0x14/0x7c fs/namespace.c:1193)
 r6:ebe95f6c r5:8339cb00 r4:00000049
[<805a48dc>] (fc_mount) from [<805aa600>] (do_new_mount_fc fs/namespace.c:3763 [inline])
[<805a48dc>] (fc_mount) from [<805aa600>] (do_new_mount fs/namespace.c:3839 [inline])
[<805a48dc>] (fc_mount) from [<805aa600>] (path_mount+0x434/0xb60 fs/namespace.c:4159)
 r5:00000413 r4:00000049
[<805aa1cc>] (path_mount) from [<805ab364>] (do_mount fs/namespace.c:4172 [inline])
[<805aa1cc>] (path_mount) from [<805ab364>] (__do_sys_mount fs/namespace.c:4361 [inline])
[<805aa1cc>] (path_mount) from [<805ab364>] (sys_mount+0x1dc/0x260 fs/namespace.c:4338)
 r10:00000015 r9:b5403587 r8:83f79000 r7:00000000 r6:85f1f240 r5:200003c0
 r4:00000000
[<805ab188>] (sys_mount) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67)
Exception stack(0xebe95fa8 to 0xebe95ff0)
5fa0:                   200003c0 00000000 00000000 20002080 200020c0 00000413
5fc0: 200003c0 00000000 00346318 00000015 003462d8 00000000 00000001 76f270dc
5fe0: 76f26e88 76f26e78 00018bc4 00130300
 r10:00000015 r9:847224c0 r8:8020029c r7:00000015 r6:00346318 r5:00000000
 r4:200003c0
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 29 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT 
Tainted: [L]=SOFTLOCKUP
Hardware name: ARM-Versatile Express
Call trace: 
[<80201a14>] (dump_backtrace) from [<80201b08>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257)
 r7:60000193 r6:60000193 r5:822a8a28 r4:00000000
[<80201af0>] (show_stack) from [<8021e410>] (__dump_stack lib/dump_stack.c:94 [inline])
[<80201af0>] (show_stack) from [<8021e410>] (dump_stack_lvl+0x5c/0x70 lib/dump_stack.c:120)
[<8021e3b4>] (dump_stack_lvl) from [<8021e43c>] (dump_stack+0x18/0x1c lib/dump_stack.c:129)
 r7:00000000 r6:00000113 r5:00000000 r4:00000001
[<8021e424>] (dump_stack) from [<81ad4c7c>] (nmi_cpu_backtrace+0x150/0x170 lib/nmi_backtrace.c:113)
[<81ad4b2c>] (nmi_cpu_backtrace) from [<81ad4dcc>] (nmi_trigger_cpumask_backtrace+0x130/0x1d8 lib/nmi_backtrace.c:62)
 r7:00000000 r6:8280c550 r5:8281af38 r4:ffffffff
[<81ad4c9c>] (nmi_trigger_cpumask_backtrace) from [<8022f124>] (arch_trigger_cpumask_backtrace+0x18/0x1c arch/arm/kernel/smp.c:852)
 r9:82ac7834 r8:8280c6d8 r7:000bb5c0 r6:84722ca8 r5:82804d80 r4:00000048
[<8022f10c>] (arch_trigger_cpumask_backtrace) from [<81adc8bc>] (trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline])
[<8022f10c>] (arch_trigger_cpumask_backtrace) from [<81adc8bc>] (__sys_info lib/sys_info.c:157 [inline])
[<8022f10c>] (arch_trigger_cpumask_backtrace) from [<81adc8bc>] (sys_info+0x68/0xa8 lib/sys_info.c:165)
[<81adc854>] (sys_info) from [<80385260>] (check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline])
[<81adc854>] (sys_info) from [<80385260>] (watchdog+0x59c/0x8d8 kernel/hung_task.c:515)
 r5:82804d80 r4:84685414
[<80384cc4>] (watchdog) from [<802814a0>] (kthread+0x11c/0x154 kernel/kthread.c:436)
 r10:00000000 r9:df819e60 r8:83103500 r7:00000000 r6:80384cc4 r5:831f8000
 r4:838808c0
[<80281384>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xdf8d5fb0 to 0xdf8d5ff8)
5fa0:                                     00000000 00000000 00000000 00000000
5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80281384 r4:838808c0
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 2811 Comm: pr/ttyAMA-1 Tainted: G             L      syzkaller #0 PREEMPT 
Tainted: [L]=SOFTLOCKUP
Hardware name: ARM-Versatile Express
PC is at sched_balance_update_blocked_averages+0x84/0xbc kernel/sched/fair.c:10025
LR is at __raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
LR is at _raw_spin_unlock+0x2c/0x50 kernel/locking/spinlock.c:186
pc : [<802a1bc0>]    lr : [<81af5654>]    psr: 20000113
sp : df805f08  ip : df805ee8  fp : df805f1c
r10: 00000101  r9 : 846f24c0  r8 : 0000001c
r7 : 00000007  r6 : 00000006  r5 : 60000113  r4 : ddde5400
r3 : 846f24c0  r2 : 00000101  r1 : 00000001  r0 : 00000001
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 30c5387d  Table: 84e3e2c0  DAC: 00000000
Call trace: frame pointer underflow
[<802a1b3c>] (sched_balance_update_blocked_averages) from [<802abb80>] (sched_balance_softirq+0x50/0x6c kernel/sched/fair.c:13090)
 r5:00000000 r4:ddde5400
[<802abb30>] (sched_balance_softirq) from [<8025a1bc>] (handle_softirqs+0x15c/0x4ec kernel/softirq.c:622)
 r5:00000020 r4:8280409c
[<8025a060>] (handle_softirqs) from [<8025a6e8>] (__do_softirq kernel/softirq.c:656 [inline])
[<8025a060>] (handle_softirqs) from [<8025a6e8>] (invoke_softirq kernel/softirq.c:496 [inline])
[<8025a060>] (handle_softirqs) from [<8025a6e8>] (__irq_exit_rcu+0x150/0x1d0 kernel/softirq.c:723)
 r10:8295bb34 r9:846f24c0 r8:00000000 r7:eb3f9e78 r6:82456cc4 r5:82491b34
 r4:846f24c0
[<8025a598>] (__irq_exit_rcu) from [<8025aa20>] (irq_exit+0x10/0x18 kernel/softirq.c:751)
 r5:82491b34 r4:826cbcdc
[<8025aa10>] (irq_exit) from [<81ae78f0>] (generic_handle_arch_irq+0x7c/0x80 kernel/irq/handle.c:293)
[<81ae7874>] (generic_handle_arch_irq) from [<81ab69a8>] (call_with_stack+0x1c/0x20 arch/arm/lib/call_with_stack.S:40)
 r9:846f24c0 r8:00000000 r7:eb3f9eac r6:ffffffff r5:60000013 r4:81af5740
[<81ab698c>] (call_with_stack) from [<80200bec>] (__irq_svc+0x8c/0xbc arch/arm/kernel/entry-armv.S:228)
Exception stack(0xeb3f9e78 to 0xeb3f9ec0)
9e60:                                                       83fc7c40 60000013
9e80: 00000000 00008c63 00000001 00000000 8295ba98 00000117 00000000 00000001
9ea0: 8295bb34 eb3f9ed4 eb3f9ed8 eb3f9ec8 80acd358 81af5740 60000013 ffffffff
[<81af5718>] (_raw_spin_unlock_irqrestore) from [<80acd358>] (spin_unlock_irqrestore include/linux/spinlock.h:407 [inline])
[<81af5718>] (_raw_spin_unlock_irqrestore) from [<80acd358>] (__uart_port_unlock_irqrestore include/linux/serial_core.h:616 [inline])
[<81af5718>] (_raw_spin_unlock_irqrestore) from [<80acd358>] (pl011_console_device_unlock+0x20/0x24 drivers/tty/serial/amba-pl011.c:2603)
[<80acd338>] (pl011_console_device_unlock) from [<802e6910>] (nbcon_emit_one+0x88/0x100 kernel/printk/nbcon.c:1165)
[<802e6888>] (nbcon_emit_one) from [<802e6b90>] (nbcon_kthread_func+0x208/0x2ec kernel/printk/nbcon.c:1271)
 r6:82ac410c r5:8295ba98 r4:846f24c0
[<802e6988>] (nbcon_kthread_func) from [<802814a0>] (kthread+0x11c/0x154 kernel/kthread.c:436)
 r10:00000000 r9:df931b48 r8:84c97600 r7:8295ba98 r6:802e6988 r5:846f24c0
 r4:83880400
[<80281384>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xeb3f9fb0 to 0xeb3f9ff8)
9fa0:                                     00000000 00000000 00000000 00000000
9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80281384 r4:83880400