"INFO: task hung in exit_mm" and "INFO: task hung in do_exit" should be duplicate crash reports

[慕冬亮]

Dear kernel developers,

I found that on the syzbot dashboard, “INFO: task hung in exit_mm”[1]
and "INFO: task hung in do_exit"[2] should share the same root cause.

The reasons for the above statement:
1) the stack trace is the same, and this title difference is due to
the inline property of "exit_mm";
2) their PoCs are the same as each other;

If you can have any issues with this statement or our information is
useful to you, please let us know. Thanks very much.

[1] “INFO: task hung in exit_mm” -
https://syzkaller.appspot.com/bug?id=dd115babf1498c3370fab8758d58940b7c6bffa4

[2] “INFO: task hung in do_exit” -
https://syzkaller.appspot.com/bug?id=3e6c42e24155e5f0125368e609bee32f2b7394fe

--
My best regards to you.

     No System Is Safe!
     Dongliang Mu