On Thu, 1 Jun 2006, Wilko Bulte wrote:
> My dual-CPU DS20 Alpha box can more or less consistently be
> forced into a panic like:
>
> FreeBSD/alpha (goldrush.wbnet) (ttyd0)^
>
> login: panic: lockmgr: thread 0xfffffc007d9d4a80, not exclusive lock holder
> 0xfffffc006052d260 unlocking
> cpuid = 1
> KDB: enter: panic
>
> Trigger is a "make -j2 release". j2 seems to be needed, not seen
it with
> -j1
>
> Unfortunately after printing the line with "KDB" the whole thing
appears to
> become completely catatonic :(
Try putting a call to critical_enter() towards the beginning of panic().
Sometimes this increases the reliability of entering the debugger by avoiding
interrupt delivery during the process of entering. If you want to be able to
continue out, you'll need a critical_exit() at the end, but that generally
isn't helpful for panic().
Robert N M Watson