Am 03.02.2015 um 13:59 schrieb Paolo Bonzini: > > > On 03/02/2015 13:11, Thomas Huth wrote: >> The userspace (QEMU) then can simply call this ioctl when it wants >> to read or write from/to virtual guest memory. Then kernel then takes >> the IPTE-lock, walks the MMU table of the guest to find out the >> physical address that corresponds to the virtual address, copies >> the requested amount of bytes from the userspace buffer to guest >> memory or the other way round, and finally frees the IPTE-lock again. >> >> Does that sound like a viable solution (IMHO it does ;-))? Or should >> I maybe try to pursue another approach? > > It looks feasible to me as well. Yes, we discussed this internally a lot and things are really tricky. The ipte lock could be exported to userspace, but we might also need to handle storage keys (and key protection) in an atomic fashion, so this really looks like the only safe way. I guess we will give it some more testing, but to me it looks like a good candidate for kvm/next after 3.20-rc1. Christian -- 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
