On 2/10/2016 10:18 PM, Dan Williams wrote:
> The pfn_t type uses an unsigned long to store a pfn + flags value. On a
> 64-bit platform the upper 12 bits of an unsigned long are never used for
> storing the value of a pfn. However, this is not true on highmem
> platforms, all 32-bits of a pfn
The pfn_t type uses an unsigned long to store a pfn + flags value. On a
64-bit platform the upper 12 bits of an unsigned long are never used for
storing the value of a pfn. However, this is not true on highmem
platforms, all 32-bits of a pfn value are used to address a 44-bit
physical address
