On Fri, 19 Feb 2021 at 08:05, <c...@etri.re.kr> wrote: > These are the machine lists that included cortex-a72 when I gave > qemu-system-aarch64 --machine xxx --cpu help.
Adding '--machine whatever' to your command line does not change the output of '--cpu help'. As Philippe says, it happens that QEMU processes --cpu before --machine, so it handles '--cpu help', prints the fixed list of supported CPUs, and ignores whether you passed a valid --machine option or not. There is no automated way to get QEMU to tell you which CPUs a particular board model supports. I recommend that you follow the advice given here https://qemu.readthedocs.io/en/latest/system/target-arm.html#choosing-a-board-model for how to choose a board model. (Short answer: if you know you want to run guest code for a specific board type, use that board type. Otherwise, use 'virt'.) Then, you should stick with the default CPU type (ie, do not pass --cpu) for that board, for all board types *except* 'virt'. For 'virt' you can pass in the CPU type you want (and the documentation lists which types it supports). -- PMM
