On 04/03/2015 15:29, Catalin Marinas wrote: > I disagree it is 100% a host-side issue. It is a host-side issue _if_ > the host tells the guest that the (virtual) device is non-coherent (or, > more precisely, it does not explicitly tell the guest that the device is > coherent). If the guest thinks the (virtual) device is non-coherent > because of information passed by the host, I fully agree that the host > needs to manage the cache coherency. > > However, the host could also pass a "dma-coherent" property in the DT > given to the guest and avoid any form of cache maintenance. If the guest > does not honour such coherency property, it's a guest problem and it > needs fixing in the guest. This isn't any different from a real physical > device behaviour. Can you add that property to the device tree for PCI devices too? Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
