Messages in this thread | | | Date | Thu, 11 Oct 2012 10:41:32 -0400 | From | Konrad Rzeszutek Wilk <> | Subject | Re: [PATCH 03/10] x86, mm: get early page table from BRK |
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On Wed, Oct 10, 2012 at 08:49:05AM -0700, Yinghai Lu wrote: > On Wed, Oct 10, 2012 at 7:17 AM, Konrad Rzeszutek Wilk > <konrad@kernel.org> wrote: > > On Tue, Oct 09, 2012 at 06:03:33PM -0700, Yinghai Lu wrote: > > >> good point, i add one line comment to the revised patch. > >> > >> +/* need 3 4k for initial PMD_SIZE, 4k for 0-ISA_END_ADDRESS */ > > > > Can you explain the math please? It sounds like this is based on > > the assumption that this you are using huge pages. But what if you > > are not? What if you can only do 4KB pages? > > yes that is some extreme case: > assume that 2M range is [2T-2M, 2T),
What is T in here? Terabyte? Is the '[' vs ')' a significance in your explanation? Should it be '[2T-2M, 2T]' ?
> one page for PGD-[2T-512g, 2T), one for PUD - [2T-1G, 2T), and one for > PMD -: [2T-2M, 2T)
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