Re: [Xen-devel] [semi-urgent Xen CS question] Re: git commit 9fd67b4ed0714ab718f1f9bd14c344af336a6df7 (x86-64: Give vvars their own page) breaks Xen PV guests (64-bit).

[Jeremy Fitzhardinge <jeremy@xxxxxxxx>]

On 07/29/2011 05:51 AM, Andrew Lutomirski wrote:
> VCGF_in_syscall: gettimeofday() (the syscall version) takes 593 ns.
> Without VCGF_in_syscall, it's 712 ns.
>
> I'd argue for using my original approach of adding a user_64bit_mode
> function -- I think it's a legitimate cleanup and Xen, for better or
> worse, really does have two long mode CPL 3 selectors.  If we removed
> selector 6 from the GDT, that would be a different story, but that
> would probably be a more intrusive change.

Sigh.  Yeah, let's see what happens.

    J


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