Subject: Stack underflow on boot problem.
To: None <amiga-dev@sun-lamp.cs.berkeley.edu>
From: Markus Illenseer <markus@TechFak.Uni-Bielefeld.DE>
List: amiga-dev
Date: 07/05/1994 23:08:05
For those who are using recent sups, there may be a stack underflow
on boot that causes hangs. So far it's happened only on my 3000
with a kernel compiled for '030's only, i.e. no FPSP or
M68040 defined in the conf file.
The symptoms are messages about an unknown trap at 0xe0,
it's an '030/68551 "tried to put bad value in MMU register" trap.
To get around it, add something like
.long 0xdeadbeef
between the
tmpstk:
and
protorp:
lines in locore.s. I'm trying to track down what causes the
stack to underflow at boot out of the tmpstk area and clobbers
the 0x80000002 value at protorp. For now adding a 1 word scratch
value allows the system to boot and function.
Not sure what all is causing this but for those playing with July
sup's this hack may be needed to boot. Mucho thanks to Michel Hitch
for pointers on tracking this down.
-Rob
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