US Patent 9904567 Limited hardware assisted dirty page logging

A hypervisor identifies a set of pages to be polled for updates made by a guest operating system, each page having a write protection attribute that causes an exit to a hypervisor upon a guest operating system attempt to update a corresponding page. The hypervisor modifies the write protection attribute for each page of the set of pages to avoid the exit to the hypervisor upon the guest attempt to update the corresponding page. The hypervisor then initiates polling of the set of pages to detect updated pages, wherein detecting updated pages comprises detecting a status indicator set to a first value. The hypervisor then logs a modification of each updated page, and resets the status indicator to a second value to indicate that the modification to each updated page has been logged.