Re: Re: [Linux PATCH] Make hugepages work in current git tree

[Dave McCracken <dcm@mccr.org>]

On Thursday 29 April 2010, Jeremy Fitzhardinge wrote:
> Looks reasonable.  I rewrote the commit comment:
> 
> Subject: [PATCH] x86/hugetlb: use set_pmd for huge pte operations
> 
> On x86, a huge pte is logically a pte, but structurally a pmd.  Among
> other issues, pmds and ptes overload some flags for multiple uses (PAT
> vs PSE), so it is necessary to know which structural level a pagetable
> entry is in order interpret it properly.
> 
> When huge pages are used within a paravirtualized system, it is therefore
> appropriate to use the pmd set of function to operate on them, so that
> the hypervisor can correctly validate the update.
> 
> Signed-off-by: Dave McCracken <dave.mccracken@oracle.com>
> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
> 
> Does this look correct?

Yes, that's an excellent summary of the issue.  Thank you.

Dave McCracken