Hi Mark, On Thu, Apr 16, 2020 at 5:57 PM Mark Rutland <mark.rutland@xxxxxxx> wrote: > On Thu, Apr 16, 2020 at 05:38:07PM +0200, Geert Uytterhoeven wrote: > > And perhaps you do want to enable some platform-specific drivers for > > VFIO pass-through? Hence having ARCH_* dependencies on those drivers > > means they cannot be enabled :-( Hmm... > > IIRC platform device passthrough requires an corresponding VFIO platform > driver in the host to handle reset and so on, but it does seem a shame If your SoC has a reset controller, that problem has been solved in a generic way, cfr. "[PATCH v5] vfio: platform: Add generic reset controller support" (https://lore.kernel.org/lkml/20181113131508.18246-1-geert+renesas@xxxxxxxxx/). Unfortunately not yet upstream. Combine with "hw/arm/sysbus-fdt: Add support for instantiating generic devices" (https://github.com/geertu/qemu/commit/180318003c08594e8e852b2285a98184f905bfa9) and you're set ;-) > to not allow the user to select a driver if they really want it. I forgot you can add "|| VIRTIO_MMIO" to the dependencies of drivers for devices that can be used with VFIO pass-through. > I guess there might be platform-specific PCIe drivers too, which might > work with VFIO regardless. Indeed. PCI is business as usual. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
