INFO: task syz.0.52060:15824 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.0.52060     state:D stack:0     pid:15824 tgid:15824 ppid:3105   task_flags:0x400040 flags:0x00000005
Call trace: 
[<81b5771c>] (__schedule) from [<81b58bb4>] (__schedule_loop kernel/sched/core.c:7311 [inline])
[<81b5771c>] (__schedule) from [<81b58bb4>] (schedule+0x2c/0xec kernel/sched/core.c:7326)
 r10:83889180 r9:83f7b100 r8:860cf200 r7:8478f918 r6:ec1c9ea0 r5:ec1c9e30
 r4:83f7b100
[<81b58b88>] (schedule) from [<8079e6d4>] (request_wait_answer fs/fuse/dev.c:743 [inline])
[<81b58b88>] (schedule) from [<8079e6d4>] (__fuse_request_send fs/fuse/dev.c:757 [inline])
[<81b58b88>] (schedule) from [<8079e6d4>] (fuse_chan_send+0x390/0x47c fs/fuse/dev.c:833)
 r5:ec1c9e30 r4:8478f8c0
[<8079e344>] (fuse_chan_send) from [<807b0c3c>] (__fuse_simple_request+0x5c/0x68 fs/fuse/req.c:69)
 r8:8645e280 r7:85e719c0 r6:86017000 r5:861a4180 r4:ec1c9ea0
[<807b0be0>] (__fuse_simple_request) from [<807a63d8>] (fuse_simple_request fs/fuse/fuse_i.h:1012 [inline])
[<807b0be0>] (__fuse_simple_request) from [<807a63d8>] (fuse_flush+0x178/0x1b4 fs/fuse/file.c:504)
 r5:850b78c0 r4:83889180
[<807a6260>] (fuse_flush) from [<805991d4>] (filp_flush+0x38/0x88 fs/open.c:1471)
 r8:86017040 r7:865fb880 r6:0000001e r5:86017000 r4:83889180
[<8059919c>] (filp_flush) from [<80599238>] (filp_close+0x14/0x28 fs/open.c:1484)
 r7:865fb880 r6:0000001e r5:83889180 r4:86017000
[<80599224>] (filp_close) from [<805cb75c>] (__range_close fs/file.c:793 [inline])
[<80599224>] (filp_close) from [<805cb75c>] (__do_sys_close_range fs/file.c:854 [inline])
[<80599224>] (filp_close) from [<805cb75c>] (sys_close_range+0x18c/0x224 fs/file.c:818)
 r5:00000004 r4:86017000
[<805cb5d0>] (sys_close_range) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67)
Exception stack(0xec1c9fa8 to 0xec1c9ff0)
9fa0:                   00000000 00000000 00000003 0000001e 00000000 7eeb8918
9fc0: 00000000 00000000 00000000 000001b4 009baf0b ffffffff 00000000 003462e4
9fe0: 7eeb8840 7eeb8830 0002853c 00130820
 r10:000001b4 r9:83f7b100 r8:8020029c r7:000001b4 r6:00000000 r5:00000000
 r4:00000000
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: 
[<80201998>] (dump_backtrace) from [<80201a8c>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257)
 r7:60000093 r6:60000093 r5:82332258 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 [<81b40dbc>] (nmi_cpu_backtrace+0x150/0x170 lib/nmi_backtrace.c:122)
[<81b40c6c>] (nmi_cpu_backtrace) from [<81b40f10>] (nmi_trigger_cpumask_backtrace+0x134/0x208 lib/nmi_backtrace.c:65)
 r7:82a0b150 r6:83320c40 r5:82a1c7b8 r4:ffffffff
[<81b40ddc>] (nmi_trigger_cpumask_backtrace) from [<8022f0f4>] (arch_trigger_cpumask_backtrace+0x18/0x1c arch/arm/kernel/smp.c:851)
 r9:82a0b2f0 r8:00000001 r7:82a1ce80 r6:82ccae2c r5:00007f26 r4:00000048
[<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b48a4c>] (trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline])
[<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b48a4c>] (__sys_info lib/sys_info.c:157 [inline])
[<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b48a4c>] (sys_info+0x68/0xa8 lib/sys_info.c:165)
[<81b489e4>] (sys_info) from [<8038f87c>] (check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline])
[<81b489e4>] (sys_info) from [<8038f87c>] (watchdog+0x3a0/0x848 kernel/hung_task.c:561)
 r5:00007f26 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
 r4:833e1140
[<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 r4:833e1140
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 2913 Comm: syslogd Tainted: G             L      syzkaller #0 PREEMPT 
Tainted: [L]=SOFTLOCKUP
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 __debug_check_no_obj_freed lib/debugobjects.c:1180 [inline]
LR is at debug_check_no_obj_freed+0x18c/0x2b4 lib/debugobjects.c:1201
pc : [<81b6207c>]    lr : [<8095baac>]    psr: 600e0013
sp : ebd71ca8  ip : ebd71cb8  fp : ebd71cb4
r10: 00000000  r9 : 8a3bf0c0  r8 : 00000100
r7 : 61c88647  r6 : 00000000  r5 : 00000000  r4 : 8a3bf180
r3 : 00008d7c  r2 : 00003514  r1 : 000e0013  r0 : 82d16ab0
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 30c5387d  Table: 84f51980  DAC: 00000000
Call trace: 
[<81b62054>] (_raw_spin_unlock_irqrestore) from [<8095baac>] (__debug_check_no_obj_freed lib/debugobjects.c:1180 [inline])
[<81b62054>] (_raw_spin_unlock_irqrestore) from [<8095baac>] (debug_check_no_obj_freed+0x18c/0x2b4 lib/debugobjects.c:1201)
[<8095b920>] (debug_check_no_obj_freed) from [<80540a1c>] (slab_free_hook mm/slub.c:2636 [inline])
[<8095b920>] (debug_check_no_obj_freed) from [<80540a1c>] (slab_free mm/slub.c:6405 [inline])
[<8095b920>] (debug_check_no_obj_freed) from [<80540a1c>] (kmem_cache_free+0x250/0x440 mm/slub.c:6532)
 r10:00000000 r9:8162e7b0 r8:84fee200 r7:00000000 r6:8a3bf0c0 r5:830e5c00
 r4:ddf6129c
[<805407cc>] (kmem_cache_free) from [<8162e7b0>] (kfree_skbmem+0xa4/0xa8 net/core/skbuff.c:1139)
 r10:00000000 r9:0000004a r8:0000004a r7:00000000 r6:854dd914 r5:8163d7a4
 r4:8a3bf0c0
[<8162e70c>] (kfree_skbmem) from [<81637a24>] (__kfree_skb net/core/skbuff.c:1206 [inline])
[<8162e70c>] (kfree_skbmem) from [<81637a24>] (consume_skb net/core/skbuff.c:1439 [inline])
[<8162e70c>] (kfree_skbmem) from [<81637a24>] (consume_skb+0x84/0x158 net/core/skbuff.c:1433)
[<816379a0>] (consume_skb) from [<8163d7a4>] (skb_free_datagram+0x14/0x18 net/core/datagram.c:324)
 r7:00000000 r6:854dd914 r5:854dd6c0 r4:8a3bf0c0
[<8163d790>] (skb_free_datagram) from [<81919810>] (__unix_dgram_recvmsg+0x29c/0x3a4 net/unix/af_unix.c:2664)
[<81919574>] (__unix_dgram_recvmsg) from [<8191994c>] (unix_dgram_recvmsg+0x34/0x38 net/unix/af_unix.c:2681)
 r10:00004004 r9:00000001 r8:84fee200 r7:00000000 r6:834487c0 r5:ebd71e70
 r4:81919918
[<81919918>] (unix_dgram_recvmsg) from [<8161fa4c>] (sock_recvmsg_nosec net/socket.c:1126 [inline])
[<81919918>] (unix_dgram_recvmsg) from [<8161fa4c>] (sock_recvmsg+0x50/0x78 net/socket.c:1148)
 r5:ebd71e70 r4:81919918
[<8161f9fc>] (sock_recvmsg) from [<8161fb10>] (sock_read_iter+0x9c/0xf4 net/socket.c:1217)
 r7:8388c800 r6:834487c0 r5:ebd71f08 r4:ebd71ef0
[<8161fa74>] (sock_read_iter) from [<8059eca8>] (new_sync_read fs/read_write.c:493 [inline])
[<8161fa74>] (sock_read_iter) from [<8059eca8>] (vfs_read fs/read_write.c:574 [inline])
[<8161fa74>] (sock_read_iter) from [<8059eca8>] (vfs_read+0x2d8/0x328 fs/read_write.c:554)
 r7:00000000 r6:007f81d4 r5:8388c800 r4:000000ff
[<8059e9d0>] (vfs_read) from [<8059f734>] (ksys_read+0xcc/0xec fs/read_write.c:716)
 r10:00000003 r9:84fee200 r8:8020029c r7:000000ff r6:007f81d4 r5:8388c800
 r4:8388c800
[<8059f668>] (ksys_read) from [<8059f764>] (__do_sys_read fs/read_write.c:725 [inline])
[<8059f668>] (ksys_read) from [<8059f764>] (sys_read+0x10/0x14 fs/read_write.c:723)
 r7:00000003 r6:007f81a8 r5:00000000 r4:00000000
[<8059f754>] (sys_read) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67)
Exception stack(0xebd71fa8 to 0xebd71ff0)
1fa0:                   00000000 00000000 00000000 007f81d4 000000ff 00000000
1fc0: 00000000 00000000 007f81a8 00000003 00000000 004ea5ec 76f5854c 76f58548
1fe0: 00000001 7ebf5c38 00000000 76d83590