INFO: task syz.1.1668:7800 blocked for more than 423 seconds.
      Tainted: G             L      syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1668      state:D stack:0     pid:7800  tgid:7799  ppid:3229   task_flags:0x40044c flags:0x00000002
Call Trace:
[<ffffffff8639c964>] context_switch kernel/sched/core.c:5260 [inline]
[<ffffffff8639c964>] __schedule+0xf10/0x4098 kernel/sched/core.c:6867
[<ffffffff8639fba0>] __schedule_loop kernel/sched/core.c:6949 [inline]
[<ffffffff8639fba0>] schedule+0xb4/0x334 kernel/sched/core.c:6964
[<ffffffff8639ff22>] schedule_preempt_disabled+0x16/0x28 kernel/sched/core.c:7021
[<ffffffff863ab03e>] rwsem_down_read_slowpath+0x4ca/0x954 kernel/locking/rwsem.c:1086
[<ffffffff863ab5a8>] __down_read_common kernel/locking/rwsem.c:1261 [inline]
[<ffffffff863ab5a8>] __down_read kernel/locking/rwsem.c:1274 [inline]
[<ffffffff863ab5a8>] down_read+0xe0/0x454 kernel/locking/rwsem.c:1539
[<ffffffff8015af96>] mmap_read_lock include/linux/mmap_lock.h:391 [inline]
[<ffffffff8015af96>] exit_mm kernel/exit.c:557 [inline]
[<ffffffff8015af96>] do_exit+0x69a/0x2828 kernel/exit.c:959
[<ffffffff8015d64e>] do_group_exit+0xca/0x258 kernel/exit.c:1112