Messages in this thread |  | | Date | Sat, 6 Oct 2018 22:41:53 +0800 | From | Baoquan He <> | Subject | Re: [PATCH 4/3] x86/mm/doc: Enhance the x86-64 virtual memory layout descriptions |
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On 10/06/18 at 02:33pm, Ingo Molnar wrote: > > * Ingo Molnar <mingo@kernel.org> wrote: > > > +======================================================== > > +| Complete virtual memory map with 4-level page tables | > > +======================================================== > > > +-------------------------------------------------------------------------------- > > +start addr | offset | end addr | size | VM area description > > +-----------------|------------|------------------|---------|-------------------- > > > + > > +# Identical layout to the 56-bit one from here on: > > + > > +ffffff8000000000 | -512 GB | fffffffeefffffff | ~507 GB | ... unused hole > > +ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space > > > +======================================================== > > +| Complete virtual memory map with 5-level page tables | > > +======================================================== > > > +ffffff8000000000 | -0.5 TB | ffffffeeffffffff | 444 GB | ... unused hole > > + > > +# Identical layout to the 47-bit one from here on: > > + > > +ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space > > So patch #2 appears to have introduced an error/typo in the 47-bit table. Note the weird size > and discontinuity of the 'unused hole' in the 47-bit table, and compare it with 56-bit table: > > fffffffeefffffff > ffffffeeffffffff > > (Note how the incorrect end address was cargo-cult-copied into the 'size' field of ~507 GB...) > > The correct number is the 56-bit one, and both tables should show the following identical > layout: > > ffffff8000000000 | -512 GB | fffffffeefffffff | 444 GB | ... unused hole > ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space > > Agreed?
Yes, you are right. I wondered why the size is a weird unaligned value. Sorry about that.
Thanks Baoquan
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