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A/UX 3.0.1 kernel panic caused by serial traffic?


Active member
I'm playing around with A/UX 3.0.1 on my SE/30, and I'm running into a strange problem where the kernel panics with "!Double Panic: unexpected kernel trap" when there is heavy incoming serial traffic. I've seen this happen both in terminal sessions using cu and when receiving network traffic over SLIP using slattconf.

Anybody got any ideas how I can go about diagnosing this? I've made sure that nothing else (i.e. getty instances, appletalk etc.) are using the serial ports, and serial I/O seems to work flawlessly in Mac OS, so I don't think it's a hardware issue.

Presumably the "double panic" message indicates that it paniced while handling a prior panic condition - anyone know how to find out what the underlying panic was?

It's a bit of a frustrating issue to diagnose, since every time it happens, there's a lengthy autorecovery on reboot at best, and manual intervention to repair the filesystem at worst (that's happened a few times now and it's not very fun!).