1. In a virtualized computer system in which a guest operating system runs on a virtual machine of a virtualized computer system and has direct access to a hardware device coupled to the virtualized computer system via a communication interface, a computer implemented method of handling interrupts from the hardware device to the guest operating system, the method comprising: receiving a physical interrupt from the hardware device on a shared interrupt line of an interrupt controller, the physical interrupt forwarded to a virtual machine (VM) kernel; masking, by the VM kernel, the shared interrupt line of the interrupt controller; issuing a physical end of interrupt (EOI) in response to the masking of the shared interrupt line of the interrupt controller, the physical EOI issued by the VM kernel; generating a virtual interrupt corresponding to the physical interrupt to the guest operating system; and the guest operating system executing an interrupt service routine corresponding to the virtual interrupt.