Re: [PATCH v4 2/3] x86/vmemmap: Drop handling of 1GB vmemmap ranges

Dave Hansen
2021-03-05T17:39:00Z

On 3/1/21 12:32 AM, Oscar Salvador wrote:
> We never get to allocate 1GB pages when mapping the vmemmap range.
> Drop the dead code both for the aligned and unaligned cases and leave
> only the direct map handling.

Could you elaborate a bit on why 1GB pages are never used? It is just
unlikely to have a 64GB contiguous area of memory that needs 1GB of
contiguous vmemmap? Or, does the fact that sections are smaller than
64GB keeps this from happening?