We have implemented dynamic instrumentation mechanism (for guest code) DECAF (https://github.com/sycurelab/DECAF) with 2.7 version of qemu, and we have a few questions regarding that:
1. Why does qemu “without” kvm so slow to run Windows 10 guest? Simply booting or connecting ssh are too slow to run Windows 10 (without kvm), so we were not able to run our user program on Windows. We cannot turn on kvm as we need a feature using tcg. The performance was Okay when running Windows XP and 7 (still without kvm), but Windows 10 is particularly slow. 2. Is it possible to keep switching between kvm and tcg at runtime? As Windows 10 is too slow without kvm, we are thinking about a workaround---running with kvm as much as possible and running with tcg only if necessary (i.e., keeping switching between kvm and tcg). Will this be technically feasible? If so, will this be quite simple to implement or need a heavy-weight engineering? Thanks. JinWoo Lee
