Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753311AbZCKJR4 (ORCPT ); Wed, 11 Mar 2009 05:17:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751803AbZCKJRr (ORCPT ); Wed, 11 Mar 2009 05:17:47 -0400 Received: from smtp-outbound-1.vmware.com ([65.115.85.69]:59631 "EHLO smtp-outbound-1.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751347AbZCKJRq (ORCPT ); Wed, 11 Mar 2009 05:17:46 -0400 Message-ID: <49B781B6.3060704@vmware.com> Date: Wed, 11 Mar 2009 10:17:42 +0100 From: Thomas Hellstrom User-Agent: Thunderbird 1.5.0.7 (X11/20060921) MIME-Version: 1.0 To: "Pallipadi, Venkatesh" CC: "Eric W. Biederman" , Linux kernel mailing list , "Siddha, Suresh B" , Nick Piggin Subject: Re: 2.6.29 pat issue References: <498ADFE3.9020907@vmware.com> <1233856988.4286.83.camel@localhost.localdomain> <498B5ADE.3090602@vmware.com> <498C062C.201@vmware.com> <20090304060857.GA18318@linux-os.sc.intel.com> <130CA3A191875048A0624FB523A55EC7075DA7CA@PA-EXMBX51.vmware.com> <20090310013953.GA11312@linux-os.sc.intel.com> <49B6232B.4050503@vmware.com> <1236706959.4529.56.camel@localhost.localdomain> In-Reply-To: <1236706959.4529.56.camel@localhost.localdomain> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1487 Lines: 51 Pallipadi, Venkatesh wrote: > On Tue, 2009-03-10 at 01:22 -0700, Thomas Hellstrom wrote: > >> Pallipadi, Venkatesh wrote: >> >>> On Fri, Mar 06, 2009 at 03:44:07PM -0800, Thomas Hellstrom wrote: >>> >>> >>>> We get the warning when we insert RAM pages using vm_insert_pfn(). >>>> Having normal RAM pages backing a PFN papping is a valid thing. >>>> >>>> >>>> >>> OK. Below is the updated patch that should fix this fully. Can you confirm? >>> >>> Thanks, >>> Venki >>> >>> >>> >> Yes, this patch should fix the problem. I'm still concerned about the >> overhead of going through the >> RAM test for each inserted page. >> >> Why can't a pfn_valid() test be used in vm_insert_pfn()? >> >> > > Because we may have to track the RAM pages as well in future. We are > changing the e820 RAM check and making it use pfn_valid. But, for that > we have to change more things in tracking of RAM pages. Today we use one > bit in page struct without any refcounting. But, more changes there are > on ts way. This change here should keep the current kernel fine without > any regression. > > Thanks, > Venki > > Ok, I understand. and yes, the regression should be fixed with the patch. Thanks, Thomas -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/