Technology for moving data between virtual machines without copies

A data processing system, comprising:

• random access memory;
• a processor in communication with the random access memory;
• a core in the processor;
• a cache in the processor;
• and
• a zero-copy memory (ZCM) manager in the processor, in communication with the core and the cache, the ZCM manager to:
• receive an access request from a first software component that executes on the core, wherein the access request involves a memory address within a cache line;
• in response to receiving the access request, (i) compare an owner tag (OTAG) associated with the memory address against a first identity tag (ITAG) for the first software component, (ii) if the OTAG matches the first ITAG, complete the access request, and (iii) if the OTAG does not match the first ITAG, abort the access request;
• and
• in response to a send request from the first software component, wherein the send request specifies an ITAG for a destination software component that executes on the core, change the OTAG associated with the memory address to match the specified ITAG for the destination software component.

A non-transitory machine-readable medium comprising instructions which, when executed by a processor, cause the processor to:

• in response to receiving an access request from a first software component, wherein the access request involves a memory address within a cache line:
• (a) compare an owner tag (OTAG) associated with the memory address against a first identity tag (ITAG) for the first software component;
• (b) if the OTAG matches the first ITAG, complete the access request, and
• (c) if the OTAG does not match the first ITAG, abort the access request;
• and
• in response to a send request from the first software component, wherein the send request specifies an ITAG for a destination software component, change the OTAG associated with the memory address to match the specified ITAG for the destination software component.