Re: more system hang debugging

Emmanuel Dreyfus <[email protected]> asked;

> What is strange is that the same exception is being handled immediatly
> after we leave trap(). If I add printf's at the beginning and the end of
> trap(), I can see that we re-enter trap() with exactly the same
> exception just after we have left it. The diagnostic log shows the same
> information forever.
>
> I beleive we never go back to user mode, because
> 1) the machine is hung
> 2) On the diagnostic log in trap(), we always see the same value for pc,
> it never moves forward.

I guess something starts wrong when exception path re-enters kernel upon
ast() condition meets prior to user return.  This seems to relate with one which
you mentioned previously.

Toru Nishimura