On Thu, 2008-04-03 at 13:47 -0500, Hollis Blanchard wrote: > > x86 virtualization implementations often needs a trampoline that's > mapped into > both host and guest virtual address space, so that's part of what > you're > seeing. > > In general though, it can be very useful for the host to own a piece > of the > guest's virtual address space. For example, the host could rewrite > problematic guest instructions to branch to host-optimized code which > avoids > hypercalls. However, this is impossible unless the host knows it can > overwrite some portion of the guest's effective address space. > > reserve_top_address() doesn't look complicated, so we might as well > keep it ?
Agreed. In fact, using the top of the address space for that is a good idea as you can do the branching there using absolute branch instructions which is simpler. Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev