From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with ESMTP id 6D00A6B01EE for ; Thu, 22 Apr 2010 22:09:58 -0400 (EDT) Date: Fri, 23 Apr 2010 11:06:32 +0900 From: Naoya Horiguchi Subject: Re: [BUG] rmap: fix page_address_in_vma() to walk through anon_vma_chain Message-ID: <20100423020632.GA7383@spritzerA.linux.bs1.fc.nec.co.jp> References: <20100422054241.GB10957@spritzerA.linux.bs1.fc.nec.co.jp> <4BD0688A.7050806@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-2022-jp Content-Disposition: inline In-Reply-To: <4BD0688A.7050806@redhat.com> Sender: owner-linux-mm@kvack.org To: Rik van Riel Cc: linux-mm , LKML , Andrew Morton , Andi Kleen List-ID: > However, for anonymous pages, page_address_in_vma only > ever determined whether the page _could_ be part of the > VMA, never whether it actually was. > > The function page_address_in_vma has always given > false positives, which means all of the callers already > check that the page is actually part of the process. I see. > This means we may be able to get away with not verifying > the anon_vma at all. After all, verifying that the VMA > has the anon_vma mapped does not mean the VMA has this > page... > > Doing away with that check gets rid of your locking > conundrum :) I get it, thank you :) I'll rewrite fix patch based on your comments. Thanks, Naoya Horiguchi -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org