From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <20d785988fd83e4ec3210d7035d8d0c1@hamnavoe.com>
To: 9fans@9fans.net
From: Richard Miller <9fans@hamnavoe.com>
Date: Sun,  6 Jan 2013 15:02:57 +0000
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Subject: [9fans] arm breakpoints
Topicbox-Message-UUID: 01fc699e-ead8-11e9-9d60-3106f5b1d025

I had a surprise when I tried to debug a user process on the raspberry pi.
The first time it hit a breakpoint, the kernel panicked.  Oops.

It turns out than on armv6 (and armv7, I think) the breakpoint instruction
causes a Prefetch Abort exception, instead of Undefined Instruction as on
previous arm architectures.

I've updated the rpi kernel source to deal with this.  I wonder if
somebody with plan 9 on an armv7 system (omap or teg2) could check
whether the same panic occurs there too?