RE: [RFC] 4-level page table directories.

Luck, Tony
2005-11-07T21:18:37Z

>Another thing: has people tested 4 level page table with 4GB hugetlb page
>size? Looks like pud is already falling short on bits and entire pgd bits
>will be falling off the 64-bit. 128-bit computing anybody? (just kidding).

I didn't try 4GB huge page ... but I did just try to build with
a 64K normal page, and the build failed with fatal errors in ivt.S
because of attempts to shift by more than 64. There are also
a gazillion[1] warnings about "left shift count >= width of type"
from all over the build.

Perhaps arch/ia64/Kconfig shouldn't let you choose 4-level tables
with a 64K pagesize?

-Tony

[1] Actually "just" 1368 warnings.