On 5 October 2015 at 13:40, Gabriel L. Somlo <somlo@xxxxxxx> wrote: > In addition, Michael's comment earlier in the thread suggests that > even my current acpi version isn't sufficiently "orthodox" w.r.t. > ACPI, and I should be providing the hardware access routine as > an ACPI/AML routine, to avoid race conditions with the rest of ACPI, > and for encapsulation. I.e. it's even rude to use the fw_cfg node's > ACPI _CRS method (the part where I'd be treating it like a DT stand-in > only to query fw_cfg's hardware specifics). If you want to try to support "firmware might also be reading fw_cfg at the same time as the kernel" this is a (painful) problem regardless of how the kernel figures out whether a fw_cfg device is present. I had assumed that one of the design assumptions of this series was that firmware would only read the fw_cfg before booting the guest kernel and never touch it afterwards. If it might touch it later then letting the guest kernel also mess with fw_cfg seems like a really bad idea. thanks -- PMM -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
