During testing virtualization , I usually met some issue and can not position the issue location (host or guest), so I would like to deeply learn QEMU code, card the work flow, understand communication mechanism between host and guest.

Targets: 1. Learn KVM Qemu code, draw work-flow chart 2. Set debug option for QEMU and re-build 3. Trace QEMU work scenarios. 4. Understand resource simulation and communication with host.