A hypervisor manages a read buffer, a write buffer and a queuing buffer in a memory used jointly by the first virtual machine and the second virtual machine, the read buffer, the write buffer and the queuing buffer having the same size. The hypervisor assigns the read buffer to a read area readable by the first virtual machine, assigns the write buffer to a write area writable by the second virtual machine and assigns the queuing buffer to a queuing area of the memory that is inaccessible to the first virtual machine and to the second virtual machine. In response to a first request by the first virtual machine, the hypervisor performs a reader-side exchange of the read buffer for the queuing buffer and in response to a second request by the second virtual machine, the hypervisor performs a writer-side exchange of the write buffer for the queuing buffer.