>>> On 11.08.15 at 19:19, <andrew.coop...@citrix.com> wrote: > KVM unilaterally reloads the host task register on vmexit, and I suspect > this is probably the way to go, but have not had time to investigate > whether there is any performance impact from doing so. Given how little > of a TSS is actually used in long mode, I wouldn't expect an `ltr` to be > as expensive as it might have been in legacy modes.
How much of the TSS is being used shouldn't matter at all for LTR execution time, since the instruction doesn't access the TSS itself (and iirc there's also no caching documented for TSS uses). Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
