A method of controlling a virtual machine of a computer, the computer comprising: a physical machine comprising an I/O adapter having a physical function that creates a virtual function; a virtualization unit that provides computer resources of the physical machine to the virtual machine; and an OS that is executed on the virtual machine, the virtualization unit creating a virtual machine to which the virtual function is assigned, the virtual machine running the OS thereon, the method comprising: a first step of detecting, by the virtualization unit, a state change of the I/O adapter; a second step of identifying, by the virtualization unit, when a state of the I/O adapter becomes a predetermined state, the virtual machine to which the virtual function is assigned; and a third step of notifying, by the virtualization unit, the OS running on the identified virtual machine of the state of the I/O adapter.