A method and computing system for handling a page fault while executing a cross-platform system call with a shared page cache. A second kernel running in a second computer system sends a system call to a first kernel running in a first computer system. The second kernel receives, from the first kernel, a memory page that is a faulted memory page in the second computer system. The second kernel updates a second validity flag denoting that the memory page is currently available to the second computer system in a second copy of the shared page cache. A first validity flag in the first computer system denotes that the memory page is currently unavailable to the first computer system in a first copy of the shared page cache. The second kernel executes the system call to obtain a result and sends the result to the first kernel.