INFO: task syz-executor.0:3571 blocked for more than 430 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:0     pid:3571  tgid:3571  ppid:1      task_flags:0x400140 flags:0x00000001
Call trace: 
[<81b55b5c>] (__schedule) from [<81b56ff4>] (__schedule_loop kernel/sched/core.c:7311 [inline])
[<81b55b5c>] (__schedule) from [<81b56ff4>] (schedule+0x2c/0xec kernel/sched/core.c:7326)
 r10:df985c04 r9:df985c0c r8:00000002 r7:60000013 r6:85ca7d10 r5:841dbd40
 r4:841dbd40
[<81b56fc8>] (schedule) from [<81b57138>] (schedule_preempt_disabled+0x18/0x24 kernel/sched/core.c:7383)
 r5:841dbd40 r4:85ca7d0c
[<81b57120>] (schedule_preempt_disabled) from [<81b5a2b0>] (__mutex_lock_common kernel/locking/mutex.c:726 [inline])
[<81b57120>] (schedule_preempt_disabled) from [<81b5a2b0>] (__mutex_lock.constprop.0+0x50c/0xa48 kernel/locking/mutex.c:821)
[<81b59da4>] (__mutex_lock.constprop.0) from [<81b5a8c0>] (__mutex_lock_slowpath+0x14/0x18 kernel/locking/mutex.c:1164)
 r10:00000142 r9:8387a791 r8:00000001 r7:00000000 r6:8376aee0 r5:85ca7b00
 r4:8376aee0
[<81b5a8ac>] (__mutex_lock_slowpath) from [<81b5a900>] (mutex_lock+0x3c/0x40 kernel/locking/mutex.c:319)
[<81b5a8c4>] (mutex_lock) from [<807ab584>] (fuse_lock_inode+0x34/0x3c fs/fuse/inode.c:593)
[<807ab550>] (fuse_lock_inode) from [<8079ff3c>] (fuse_lookup+0x60/0x170 fs/fuse/dir.c:623)
[<8079fedc>] (fuse_lookup) from [<805aec08>] (__lookup_slow+0x64/0xfc fs/namei.c:1919)
 r9:8387a791 r8:85ca7b00 r7:00000403 r6:df985e60 r5:83527770 r4:8376aee0
[<805aeba4>] (__lookup_slow) from [<805aecd8>] (lookup_slow+0x38/0x50 fs/namei.c:1936)
 r9:8387a791 r8:df985e58 r7:00000403 r6:df985e60 r5:83527770 r4:85ca7b80
[<805aeca0>] (lookup_slow) from [<805b2ba4>] (walk_component fs/namei.c:2282 [inline])
[<805aeca0>] (lookup_slow) from [<805b2ba4>] (link_path_walk+0x570/0x6b8 fs/namei.c:2656)
 r7:00000000 r6:df985e58 r5:fefefeff r4:8387a790
[<805b2634>] (link_path_walk) from [<805b5874>] (path_openat+0x80/0x1260 fs/namei.c:4855)
 r10:00000142 r9:83fc6b80 r8:df985e58 r7:df985f20 r6:df985f20 r5:8387a78c
 r4:8387a780
[<805b57f4>] (path_openat) from [<805b6b0c>] (do_file_open+0xb8/0x150 fs/namei.c:4888)
 r10:00000142 r9:841dbd40 r8:00000003 r7:ffffff9c r6:df985f20 r5:841dbd40
 r4:8387a780
[<805b6a54>] (do_file_open) from [<8059b8d8>] (do_sys_openat2+0x8c/0xf0 fs/open.c:1368)
 r8:8020029c r7:00090c90 r6:ffffff9c r5:8387a780 r4:00000003
[<8059b84c>] (do_sys_openat2) from [<8059bdf0>] (do_sys_open fs/open.c:1374 [inline])
[<8059b84c>] (do_sys_openat2) from [<8059bdf0>] (__do_sys_openat fs/open.c:1390 [inline])
[<8059b84c>] (do_sys_openat2) from [<8059bdf0>] (sys_openat+0x88/0xd8 fs/open.c:1385)
 r7:00000142 r6:00000000 r5:00090c90 r4:ffffff9c
[<8059bd68>] (sys_openat) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67)
Exception stack(0xdf985fa8 to 0xdf985ff0)
5fa0:                   00000000 0002fe94 ffffff9c 00090c90 000a4800 00000000
5fc0: 00000000 0002fe94 00000000 00000142 000001f4 00000002 7ecd25ec 7ecd2650
5fe0: 00120000 7ecd2548 000427a4 00045738
 r5:0002fe94 r4:00000000
INFO: task syz-executor.0:3571 is blocked on a mutex likely owned by task syz-executor.0:3977.
INFO: task syz-executor.0:3977 blocked for more than 430 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:0     pid:3977  tgid:3968  ppid:3571   task_flags:0x400140 flags:0x00000005
Call trace: 
[<81b55b5c>] (__schedule) from [<81b56ff4>] (__schedule_loop kernel/sched/core.c:7311 [inline])
[<81b55b5c>] (__schedule) from [<81b56ff4>] (schedule+0x2c/0xec kernel/sched/core.c:7326)
 r10:00000001 r9:dfa09c94 r8:85029a00 r7:85848d08 r6:dfa09bf0 r5:dfa09b40
 r4:856a6200
[<81b56fc8>] (schedule) from [<8079ce24>] (request_wait_answer fs/fuse/dev.c:743 [inline])
[<81b56fc8>] (schedule) from [<8079ce24>] (__fuse_request_send fs/fuse/dev.c:757 [inline])
[<81b56fc8>] (schedule) from [<8079ce24>] (fuse_chan_send+0x390/0x47c fs/fuse/dev.c:833)
 r5:dfa09b40 r4:85848cb0
[<8079ca94>] (fuse_chan_send) from [<807af38c>] (__fuse_simple_request+0x5c/0x68 fs/fuse/req.c:69)
 r8:84f891c0 r7:852e0800 r6:85c3ade8 r5:857e3480 r4:dfa09bf0
[<807af330>] (__fuse_simple_request) from [<8079fd18>] (fuse_simple_request fs/fuse/fuse_i.h:1012 [inline])
[<807af330>] (__fuse_simple_request) from [<8079fd18>] (fuse_lookup_name+0xc0/0x284 fs/fuse/dir.c:577)
 r5:00000000 r4:dfa09c98
[<8079fc58>] (fuse_lookup_name) from [<8079ff68>] (fuse_lookup+0x8c/0x170 fs/fuse/dir.c:624)
 r10:00000142 r9:00000001 r8:00000001 r7:00000000 r6:85c3add0 r5:85ca7b00
 r4:85c3add0
[<8079fedc>] (fuse_lookup) from [<805aec08>] (__lookup_slow+0x64/0xfc fs/namei.c:1919)
 r9:8387a491 r8:85ca7b00 r7:00000401 r6:dfa09e60 r5:83527770 r4:85c3add0
[<805aeba4>] (__lookup_slow) from [<805aecd8>] (lookup_slow+0x38/0x50 fs/namei.c:1936)
 r9:8387a491 r8:dfa09e58 r7:00000401 r6:dfa09e60 r5:83527770 r4:85ca7b80
[<805aeca0>] (lookup_slow) from [<805b2ba4>] (walk_component fs/namei.c:2282 [inline])
[<805aeca0>] (lookup_slow) from [<805b2ba4>] (link_path_walk+0x570/0x6b8 fs/namei.c:2656)
 r7:00000000 r6:dfa09e58 r5:fefefeff r4:8387a490
[<805b2634>] (link_path_walk) from [<805b5874>] (path_openat+0x80/0x1260 fs/namei.c:4855)
 r10:00000142 r9:83881b80 r8:dfa09e58 r7:dfa09f20 r6:dfa09f20 r5:8387a48c
 r4:8387a480
[<805b57f4>] (path_openat) from [<805b6b0c>] (do_file_open+0xb8/0x150 fs/namei.c:4888)
 r10:00000142 r9:856a6200 r8:00000001 r7:ffffff9c r6:dfa09f20 r5:856a6200
 r4:8387a480
[<805b6a54>] (do_file_open) from [<8059b8d8>] (do_sys_openat2+0x8c/0xf0 fs/open.c:1368)
 r8:8020029c r7:76b5fd10 r6:ffffff9c r5:8387a480 r4:00000005
[<8059b84c>] (do_sys_openat2) from [<8059bdf0>] (do_sys_open fs/open.c:1374 [inline])
[<8059b84c>] (do_sys_openat2) from [<8059bdf0>] (__do_sys_openat fs/open.c:1390 [inline])
[<8059b84c>] (do_sys_openat2) from [<8059bdf0>] (sys_openat+0x88/0xd8 fs/open.c:1385)
 r7:00000142 r6:00040000 r5:76b5fd10 r4:ffffff9c
[<8059bd68>] (sys_openat) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67)
Exception stack(0xdfa09fa8 to 0xdfa09ff0)
9fa0:                   00000000 00000000 ffffff9c 76b5fd10 00020002 00000000
9fc0: 00000000 00000000 00040000 00000142 6e740000 00000000 76b5fd10 20000a40
9fe0: 76b5fc40 76b5fc2c 00067fe4 00069418
 r5:00000000 r4:00000000
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT 
Hardware name: ARM-Versatile Express
Call trace: 
[<80201998>] (dump_backtrace) from [<80201a8c>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257)
 r7:60000093 r6:60000093 r5:82332044 r4:00000000
[<80201a74>] (show_stack) from [<8021e5e0>] (__dump_stack lib/dump_stack.c:94 [inline])
[<80201a74>] (show_stack) from [<8021e5e0>] (dump_stack_lvl+0x5c/0x70 lib/dump_stack.c:120)
[<8021e584>] (dump_stack_lvl) from [<8021e60c>] (dump_stack+0x18/0x1c lib/dump_stack.c:129)
 r7:00000000 r6:00000013 r5:00000000 r4:00000001
[<8021e5f4>] (dump_stack) from [<81b3f1fc>] (nmi_cpu_backtrace+0x150/0x170 lib/nmi_backtrace.c:122)
[<81b3f0ac>] (nmi_cpu_backtrace) from [<81b3f350>] (nmi_trigger_cpumask_backtrace+0x134/0x208 lib/nmi_backtrace.c:65)
 r7:82a0b150 r6:83320c40 r5:82a1c7b8 r4:ffffffff
[<81b3f21c>] (nmi_trigger_cpumask_backtrace) from [<8022f0f4>] (arch_trigger_cpumask_backtrace+0x18/0x1c arch/arm/kernel/smp.c:851)
 r9:82a0b2f0 r8:00000002 r7:82a1ce80 r6:82ccae2c r5:00007f55 r4:00000048
[<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b46e8c>] (trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline])
[<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b46e8c>] (__sys_info lib/sys_info.c:157 [inline])
[<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b46e8c>] (sys_info+0x68/0xa8 lib/sys_info.c:165)
[<81b46e24>] (sys_info) from [<8038f87c>] (check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline])
[<81b46e24>] (sys_info) from [<8038f87c>] (watchdog+0x3a0/0x848 kernel/hung_task.c:561)
 r5:00007f55 r4:0000000a
[<8038f4dc>] (watchdog) from [<80281708>] (kthread+0x11c/0x154 kernel/kthread.c:436)
 r10:00000000 r9:df819e60 r8:831d5600 r7:00000000 r6:8038f4dc r5:83320c40
 r4:833e1100
[<802815ec>] (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 r5:802815ec r4:833e1100
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 2824 Comm: pr/ttyAMA-1 Not tainted syzkaller #0 PREEMPT 
Hardware name: ARM-Versatile Express
PC is at __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
PC is at _raw_spin_unlock_irqrestore+0x28/0x54 kernel/locking/spinlock.c:198
LR is at spin_unlock_irqrestore include/linux/spinlock.h:408 [inline]
LR is at __uart_port_unlock_irqrestore include/linux/serial_core.h:618 [inline]
LR is at pl011_console_device_unlock+0x20/0x24 drivers/tty/serial/amba-pl011.c:2700
pc : [<81b604bc>]    lr : [<80afe9f4>]    psr: 600f0013
sp : eb155ec8  ip : eb155ed8  fp : eb155ed4
r10: 82b5cd1c  r9 : 00000001  r8 : 00000000
r7 : 00000117  r6 : 82b5cc80  r5 : 00000000  r4 : 00000001
r3 : 000005e4  r2 : 00000000  r1 : 600f0013  r0 : 84766440
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 30c5387d  Table: 84ce62c0  DAC: 00000000
Call trace: 
[<81b60494>] (_raw_spin_unlock_irqrestore) from [<80afe9f4>] (spin_unlock_irqrestore include/linux/spinlock.h:408 [inline])
[<81b60494>] (_raw_spin_unlock_irqrestore) from [<80afe9f4>] (__uart_port_unlock_irqrestore include/linux/serial_core.h:618 [inline])
[<81b60494>] (_raw_spin_unlock_irqrestore) from [<80afe9f4>] (pl011_console_device_unlock+0x20/0x24 drivers/tty/serial/amba-pl011.c:2700)
[<80afe9d4>] (pl011_console_device_unlock) from [<802ec160>] (nbcon_emit_one+0x88/0x100 kernel/printk/nbcon.c:1165)
[<802ec0d8>] (nbcon_emit_one) from [<802ec3e0>] (nbcon_kthread_func+0x208/0x2ec kernel/printk/nbcon.c:1271)
 r6:82cc72ec r5:82b5cc80 r4:85683d40
[<802ec1d8>] (nbcon_kthread_func) from [<80281708>] (kthread+0x11c/0x154 kernel/kthread.c:436)
 r10:00000000 r9:eacfdb38 r8:854ae600 r7:82b5cc80 r6:802ec1d8 r5:85683d40
 r4:83830c40
[<802815ec>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xeb155fb0 to 0xeb155ff8)
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 r5:802815ec r4:83830c40