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From:   Dave Hansen <dave.hansen@intel.com>
Subject: Re: [RFC PATCH v0 0/6] x86/AMD: Userspace address tagging
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On 3/11/22 01:36, David Laight wrote:
> Wikipedia also notes:
>     Intel has implemented a scheme with a 5-level page table, which allows
>     Intel 64 processors to support a 57-bit virtual address space.
>     Further extensions may allow full 64-bit virtual address space and
>     physical memory by expanding the page table entry size to 128-bit,
>     and reduce page walks in the 5-level hierarchy by using a larger 64 KiB
>     page allocation size that still supports 4 KiB page operations for
>     backward compatibility.
> If they implement 64K pages then you lose the extra bits.

I can't believe I need to say this:  Wikipedia is not an authoritative
source about what anyone is going to do with their CPUs in the future.
Please don't base any Linux decisions off this information.