On 29 July 2015 at 12:16, Pavel Fedin <p.fe...@samsung.com> wrote: >> I don't really want to have two different address layouts >> just to work around a kernel bug > > They will not be really different. Just for 32-bit machines > there will be no second MMIO window, and for 64-bit ones there > will be. Nothing else will be different.
That's still a difference. (Also, even a 32-bit guest might have a 40-bit physical address space and be potentially able to use an upper MMIO window.) >> if we could fix the kernel bug instead... > > We could. But what about existing installations? They will be forced to > upgrade kernels, we will not have backwards compatibility option. And users > will complain that "my old VM stopped working with new qemu". > Well, this discussion seems to be stuck, so let's move on. > What is your final word? (1) We should confirm whether this really is a guest kernel bug (as opposed to the device tree QEMU emits not being in spec) (2) If it is a kernel bug, submit a patch to fix it (3) Consider a workaround for older guests anyway. The scope of that workaround would depend on exactly which guests are affected, which is presumably something we figured out during step (1). thanks -- PMM
