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Subject: pte_addr_t size reduction for 64 GB case?
From: Albert Cahalan <albert@users.sf.net>
To: linux-kernel mailing list <linux-kernel@vger.kernel.org>
Cc: riel@redhat.com
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Date: 19 May 2004 00:42:11 -0400
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When handling 64 GB on i386, pte_addr_t really only
needs 33 bits to find the PTE. It sure doesn't need
the full 64 bits it is using.

How about cheating a bit? If the pte_addr_t only had
the high 32 bits of the 36-bit pointer, it would point
to a pair of the 8-byte PTEs in a 16-byte chunk of RAM.
Then simply examine the PTEs to see which one is the
correct one.