1. A method for operating a computer system, comprising: executing a first operating system in a virtual machine environment by a processor of the computer system; allocating, by the first operating system, a selected memory region as a shared memory region shared by the first operating system and a second operating system executing in the virtual machine environment; notifying, by the first operating system, the second operating system, executing in the virtual machine environment of the computer system, of the shared memory region; and in response to an error affecting the first operating system, accessing the shared memory region and replaying, by the second operating system, at least one write operation stored in the shared memory region.