alt Hacker NewsPossible user-space DoS on Linux when running on an ARM7 CPU in just two instructions. Would that be a record? If the kernel was configured to support OABI (exclusively or together with EABI), I think the following two-ARM-instr binary will simply crash the kernel if the core has alignment checking: SUB PC, PC, #2; SWI 0. I am not sure how common such configs are, but someone should maybe fix that? The fix would be only one extra instruction.
6502 can do it in one. 12 opcodes are glitched in a way that permanently halts the CPU, by causing it to never reset the internal tick counter (...sortof) that starts the next instruction. Recovery is only possible with a power cycle.