From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: Re: [Linux PATCH] Make hugepages work in current git tree Date: Thu, 29 Apr 2010 14:51:51 -0700 Message-ID: <4BD9FF77.1040300@goop.org> References: <20100428140825.17161.27594.sendpatchset@magnum.int.mccr.org> <4BD9DE3D.9070204@goop.org> <201004291643.16613.dcm@mccr.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <201004291643.16613.dcm@mccr.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Dave McCracken Cc: xen-devel@lists.xensource.com, Jan Beulich List-Id: xen-devel@lists.xenproject.org On 04/29/2010 02:43 PM, Dave McCracken wrote: > 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 >> Signed-off-by: Jeremy Fitzhardinge >> >> Does this look correct? >> > Yes, that's an excellent summary of the issue. Thank you. > Have you tested this patch on native as well as under Xen? J