On Tue, Sep 27, 2016 at 7:04 PM, Markus Armbruster <arm...@redhat.com> wrote: > Alistair Francis <alistair.fran...@xilinx.com> writes: > >> On Tue, Sep 27, 2016 at 8:40 AM, Markus Armbruster <arm...@redhat.com> wrote: >>> Paolo Bonzini <pbonz...@redhat.com> writes: >>> >>>> It does whatever cpu_physical_memory_write_rom (and hence >>>> cpu_memory_rw_debug, which has more callers) do. >>>> >>>>> What happens when you try to monkey-patch and address that isn't >>>>> connected to anything? >>>> >>>> /dev/null >>>> >>>>> What happens when you try to monkey-patch some device's ROM? >>>> >>>> Overwritten. >>>> >>>>> Memory-mapped I/O? >>>> >>>> Ignored. >>>> >>>>> What happens when you monkey-patch persistent memory, such as pflash >>>>> backed by a block backend? >>>> >>>> Overwritten (but not flushed). >>>> >>>>> What happens if the address range crosses device boundaries? >>>> >>>> Writes over each area separately. >>> >>> Rejecting the ones that don't actually load stuff would be nice, but not >>> a condition for merging this. >>> >>>>> >> If we decide to use this argument for the present interface design, I >>>>> >> want it recorded in the code and commit messages. >>>>> >>>>> Fair request, don't you think? >>>> >>>> Yes, of course. >>> >>> Okay, looking forward to these improvements. >> >> Ok, so does this mean with the correct justification that Markus >> mentions above this is fine to keep using -device? > > Yes, I've convinced myself that -device is no worse than -object. All > I'm asking for is to record the argument for -device properly. > > It took me a while to arrive at this conclusion. If you'd like to > retrace my steps, look for "An argument for using -device could go as > follows" in Message-ID: <87ponvxcit....@dusky.pond.sub.org>. > >> The justification is along the lines of the backend required is so >> trivial that we just merged it in with the frontend. > > Two points: one, why is this a device, and two, why isn't it a split > device. Point one is more important. The argument I could by there: > it's a thoroughly weird device that provides no hardware interface of > its own, but instead monkey patches memory provided by something else > (devices or the board).
Sounds fair. I'm resending my last two patches now with an updated commit message. Thanks, Alistair >
