INFO: task syz.3.420:8222 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.420       state:D stack:26024 pid:8222  tgid:8221  ppid:6924   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 wb_wait_for_completion+0x15f/0x260
 sync_inodes_sb+0x1bb/0xa10
 __iterate_supers+0x13d/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4bcf58ebe9
RSP: 002b:00007f4bd0346038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f4bcf7b5fa0 RCX: 00007f4bcf58ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f4bcf7b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4bcf7b6038 R14: 00007f4bcf7b5fa0 R15: 00007ffdf124ca48
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7789 Comm: bch-rebalance/l Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70
Code: 89 fb e8 23 00 00 00 48 8b 3d c4 49 fe 0b 48 89 de 5b e9 73 98 58 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 50 a0 92 65 8b 15 e8 a4
RSP: 0018:ffffc9000305f060 EFLAGS: 00000202
RAX: ffffffff84442327 RBX: ffffc9000305f100 RCX: ffff888116505640
RDX: ffffc9000305f100 RSI: ffff88803dc5fa98 RDI: ffff88803dc5fa58
RBP: ffffc9000305f170 R08: ffffc9000305f10f R09: 0000000000000000
R10: ffffc9000305f100 R11: fffff5200060be22 R12: ffff88803dc5fa98
R13: dffffc0000000000 R14: ffff88803dc5fa58 R15: ffff88803dc5fa58
FS:  0000000000000000(0000) GS:ffff8881a3c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000012856c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 bch2_varint_decode_fast+0x26/0x190
 bch2_inode_unpack+0x393/0x2810
 bch2_move_get_io_opts_one+0x464/0x670
 do_rebalance_extent+0x323/0x1fe0
 bch2_rebalance_thread+0x126a/0x1f80
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
