Re: [Xen-devel] [PATCH] vmwrite high 32 bits of 64bit VMCS fields when in PAE mode

[Keir Fraser <keir@xxxxxxxxxxxxx>]

On 11/7/07 06:58, "Li, Xin B" <xin.b.li@xxxxxxxxx> wrote:

>> Oh, furthermore with a 32-bit build of Xen we have to be safe for the
> case
>> that VMX_BASIC_MSR[48]==1 (which Vol 3B Appendix G.1 says is true for
> non
>> Intel64 CPUs like Yonah). In this case the physical pointers poked into
> the
>> VMCS are limited to 32 bits. We may as well limit all such structures
> to
>> below 4GB in all cases with a 32-bit build of Xen.
>> 
> 
> So we need keep this mind for all data structures referenced by pointers
> in a VMCS when on 32bit Xen, or maybe how about add a memory allocation
> function wrapper for this purpose?

I think I fixed this now. Most of the structures were inside the Xen image
(io_bitmap) or were allocated from Xen heap (msr_bitmap, vmcs, apic_access).
The only exception was the apic_regs page -- I now restricted it to 32-bit
addresses on a 32-bit build of Xen if running on an Intel CPU.

Changeset 15526 in the staging tree.

 -- Keir


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel