Cross-virtual machine side channel attack core defense method and system

The invention relates to a cross-virtual machine side channel attack core defense method and system, and the method comprises the steps: S1, enabling a protected virtual machine to actively generate a VMExit event through modifying an execution call statement of a sensitive library function, and then entering a Hypercall processing module; s2, the Hypercall processing module analyzes to obtain a specific execution position of a sensitive library function of the protected virtual machine and transmits the specific execution position to an event notification module; s3, the event notification module receives the notification from the Hypercall processing module, establishes a communication channel between the kernel space and the user space, and sends the notification to the Cache monitoring module; s4, the Cache monitoring module receives the notification from the event notification module, a hardware performance counter is started to monitor the performance of the co-resident virtual machine, and whether the