Hello!
How should one port fw_cfg to other QEMU machines? Context: - I found a possible bug on the Debian builds for Raspberry Pi 4 that is only triggered when I try to launch it on QEMU; - I wrote an issue on systemd (I thought it had something to do with logind) and they requested me to only fill bugs if they show up on the upstream. - I tried baking systemd with mkosi – however, to test with mkosi and qemu, it uses fw_cfg [1] which seems specific to the virt machine on ARM. - Opened an issue [2] and started working on that [3] However, I still don't understand exactly how fw_cfg works. My current understanding is that it is a device that, when connected some memory mapping will happen on the guest so that it can access this memmap. TL;DR which steps should I take to onboard fw_cfg to machines such as raspi4b? Thanks! Anne [1] https://github.com/systemd/mkosi/blob/6c33859a1b445e0bff19d9e7f28158140893a3e4/mkosi/config.py#L456 [2] https://gitlab.com/qemu-project/qemu/-/issues/2695 [3] https://gitlab.com/retpolanne/qemu/-/commit/86fca16555385c3685b7a1489a9cfaa255e148cf
