virtual: 0.939 device: 0.846 VMM: 0.734 kernel: 0.614 vnc: 0.601 hypervisor: 0.589 graphic: 0.506 boot: 0.492 architecture: 0.457 register: 0.455 PID: 0.448 risc-v: 0.376 debug: 0.370 KVM: 0.366 network: 0.359 permissions: 0.352 performance: 0.322 semantic: 0.265 i386: 0.263 arm: 0.251 socket: 0.249 x86: 0.234 TCG: 0.226 mistranslation: 0.189 peripherals: 0.161 ppc: 0.142 assembly: 0.115 files: 0.089 user-level: 0.059 Prevent virtual machine memory leakage Description of problem: The data written in the virtual machine does not clear the memory after the virtual machine is shut down. When the virtual machine with large memory is started, it may access the data of the previous virtual machine Steps to reproduce: 1. create a virtual machine with large size memory( 80% of the host's Physical memory) 2. Request all free memory and write the characteristic string in vm 3. restart the vm 4. Request all free memory and query the last character string written Additional information: