On Wed, Aug 27, 2014 at 6:27 PM, Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx> wrote: > On Wed, Aug 27, 2014 at 07:46:46AM +0100, Stefan Hajnoczi wrote: >> On Tue, Aug 26, 2014 at 10:16 PM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote: >> > There are two outstanding issues. virtio_net warns if DMA debugging >> > is on because it does DMA from the stack. (The warning is correct.) >> > This also is likely to do something unpleasant to s390. >> > (Maintainers are cc'd -- I don't know what to do about it.) >> >> This changes the semantics of vring and breaks existing guests when >> bus address != physical address. > > Isn't that what this is suppose to fix? Right now the semantics of the > vring is that bus address == physical address. Today the assumption is that the device emulation code has access to guest physical memory (no translation necessary). Changing the semantics breaks today's guests. You need to make this change in a way so that existing guests don't break. Stefan -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
