[Qemu-devel] RE: [Xen-devel] Recursion in cpu_physical_memory_rw

[Li, Xin B]

>
>A number of qemu driver backends (such as rtl8139) call the function
>cpu_physical_memory_rw to read/write guest memory.  The target guest
>memory address is often supplied by the guest.  This opens up the
>possibility of a guest giving an address which happens to be an MMIO
>address which can potentially lead to infinite recursion involving
>cpu_physical_memory_rw.
>
>Since these driver backends really only need to access system memory,
>we could simply provide a new access interface that does not allow
>MMIO addresses.
>
>Any comments on this problem?
>

The interface called paddr_is_ram should help.
-Xin