On 09/05/2014 08:22 AM, Toshi Kani wrote: > On Fri, 2014-09-05 at 08:07 -0700, H. Peter Anvin wrote: >> On 09/05/2014 07:00 AM, Toshi Kani wrote: >>> >>> That's a fine idea, but as Ingo also suggested, I am going to disable >>> this feature on all Pentium 4 models. That should give us a safety >>> margin. Using slot 4 has a benefit that it keeps the PAT setup >>> consistent with Xen. >>> >> >> Slot 4 is also the maximally problematic one, because it is the one that >> might be incorrectly invoked for the page tables themselves. > > Good point. I wonder if Xen folks feel strongly about keeping the PAT > setup consistent with the kernel. If not, we may choose to use slot 6 > (or 7). > Who cares what the Xen folks "feel strongly about"? If strong feelings were a design criterion Xen support would have been pulled from the kernel a long, long time ago. The important thing is how to design for the situation that we currently have to live with. -hpa -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>