On 24 April 2015 at 09:46, Catalin Vasile <catalinvasil...@gmail.com> wrote: > Does a physical memory address in a guest points to the same memory as qemu? > For example: if I have a physical pointer 0x34 in the guest, does it > point to the same location that qemu points with 0x34 address?
As an additional point to Paolo's answer, consider that: (1) a guest physical address alone may not be sufficient to identify the host memory/device [consider ARM TrustZone where you also need to know the Secure/NonSecure attribute] (2) a guest physical address may not map to anything on the host (3) a guest physical address may map to an emulated device, not host RAM (4) multiple guest physical addresses may map to a single host RAM address [if the RAM is aliased to multiple physaddrs] (5) host memory that is part of the machine model may not be mapped to any guest physical address [consider a device with a block of "ram" accessed via set-address/write-data commands, or a PCI device with a BAR that has been temporarily unmapped by the guest] There are a lot of odd cases that the memory system infrastructure deals with for you... -- PMM
