From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756171Ab0D1SEL (ORCPT ); Wed, 28 Apr 2010 14:04:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:26001 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754850Ab0D1SEJ (ORCPT ); Wed, 28 Apr 2010 14:04:09 -0400 Date: Wed, 28 Apr 2010 20:03:36 +0200 From: Andrea Arcangeli To: Rik van Riel Cc: Mel Gorman , Linux-MM , LKML , Minchan Kim , KAMEZAWA Hiroyuki , Christoph Lameter , Andrew Morton Subject: Re: [RFC PATCH] take all anon_vma locks in anon_vma_lock Message-ID: <20100428180336.GC510@random.random> References: <1272403852-10479-1-git-send-email-mel@csn.ul.ie> <1272403852-10479-3-git-send-email-mel@csn.ul.ie> <20100427231007.GA510@random.random> <20100428091555.GB15815@csn.ul.ie> <20100428153525.GR510@random.random> <20100428155558.GI15815@csn.ul.ie> <20100428162305.GX510@random.random> <20100428134719.32e8011b@annuminas.surriel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100428134719.32e8011b@annuminas.surriel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 28, 2010 at 01:47:19PM -0400, Rik van Riel wrote: > static inline void anon_vma_unlock(struct vm_area_struct *vma) never mind as this is RFC, lock is clear enough > @@ -1762,7 +1760,8 @@ static int expand_downwards(struct vm_area_struct *vma, > if (error) > return error; > > - anon_vma_lock(vma); > + spin_lock(&mm->page_table_lock); > + anon_vma_lock(vma, &mm->page_table_lock); This will cause a lock inversion (page_table_lock can only be taken after the anon_vma lock). I don't immediately see why the page_table_lock here though?