Patent · US Active

Direct memory access tracking for pass-through devices in virtualized environments

US11960422B2 · kind B2 · utility

0Cited by
6References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 28, 2019
Grant dateApr 16, 2024
Priority date
Expiry dateJul 28, 2039

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2212/657
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Systems, apparatuses and methods may provide for a frontend driver that notifies a hypervisor of a map request from a guest driver of a device, wherein the device is passed through to and directly controlled by a virtual machine, and wherein the map request is associated with an attempt of the device to access a guest memory page in a virtualized execution environment. The frontend driver may also determine whether the guest memory page is pinned and send a map hypercall to the hypervisor if the guest memory page is not pinned. Additionally, the hypervisor may determine that the guest memory page is pinned, determine, based on a direct memory access (DMA) bitmap, that an unmap request from the guest driver has been issued, and unpin the guest memory page.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.