Memory deduplication for encrypted virtual machines

A method comprising:

• selecting, by a virtual machine executing on a processor, a target memory page stored in an encrypted format in an encrypted memory of the virtual machine, the encrypted memory being inaccessible to a hypervisor configured to manage the virtual machine;
• storing, by the virtual machine, an unencrypted copy of the target memory page to a shared memory that is accessible to the hypervisor;
• executing, by the hypervisor, a deduplication process with respect to the unencrypted copy of the target memory page stored in the shared memory, wherein the deduplication process executed by the hypervisor involves comparing the unencrypted copy of the target memory page stored in the shared memory to an unencrypted copy of another memory page to determine whether the target memory page is duplicative of the other memory page;
• subsequent to storing the unencrypted copy of the target memory page to the shared memory, removing, by the virtual machine, the target memory page from the encrypted memory;
• and
• subsequent to removing the target memory page from the encrypted memory, prompting the hypervisor to reallocate memory space of the encrypted memory previously used to store the target memory page.

A system comprising:

• a processor;
• and
• a non-transitory computer-readable memory comprising instructions that are executable by the processor for causing the processor to:
• select, by a virtual machine, a target memory page stored in an encrypted format in an encrypted memory of the virtual machine, the encrypted memory being inaccessible to a hypervisor configured to manage the virtual machine;
• store, by the virtual machine, an unencrypted copy of the target memory page to a shared memory that is accessible to the hypervisor;
• execute, by the hypervisor, a deduplication process with respect to the unencrypted copy of the target memory page stored in the shared memory, wherein the deduplication process executed by the hypervisor involves comparing the unencrypted copy of the target memory page stored in the shared memory to an unencrypted copy of another memory page to determine whether the target memory page is duplicative of the other memory page;
• subsequent to storing the unencrypted copy of the target memory page to the shared memory, remove, by the virtual machine, the target memory page from the encrypted memory;
• and
• subsequent to removing the target memory page from the encrypted memory, prompt, by the virtual machine, the hypervisor to reallocate memory space of the encrypted memory previously used to store the target memory page.