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D4D4
¶ A co-worker of mine was looking at some disassembled ARM code the other day, and discovered something weird. Lots of d4d4 instructions, scattered about.
I couldn’t find any messages on the mailing list about this from Theo de Raadt, so I guess we just have to live with Ueyama’s testimony that he thought 0xd4 would be a good byte to repeat as a trap instruction. It should be unreachable, but the whole point of a trap instruction is to halt the processor, not send it off on a random walk through your codebase. So after a fun night of spelunking through source code, commit logs, and manuals, I feel like I’ve learned something.
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