Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753819Ab0DAHVd (ORCPT ); Thu, 1 Apr 2010 03:21:33 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:39894 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752514Ab0DAHV1 (ORCPT ); Thu, 1 Apr 2010 03:21:27 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Matt Mackall Subject: Re: [PATCH] proc: pagemap: Hold mmap_sem during page walk Cc: kosaki.motohiro@jp.fujitsu.com, KAMEZAWA Hiroyuki , Linus Torvalds , San Mehat , linux-kernel@vger.kernel.org, Brian Swetland , Dave Hansen , Andrew Morton , n-horiguchi@ah.jp.nec.com In-Reply-To: <1270105771.3552.1143.camel@calx> References: <20100401153428.d49c6345.kamezawa.hiroyu@jp.fujitsu.com> <1270105771.3552.1143.camel@calx> Message-Id: <20100401161927.BE4F.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Mailer: Becky! ver. 2.50.07 [ja] Date: Thu, 1 Apr 2010 16:21:16 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1232 Lines: 34 > On Thu, 2010-04-01 at 15:34 +0900, KAMEZAWA Hiroyuki wrote: > > On Thu, 1 Apr 2010 15:09:56 +0900 > > KAMEZAWA Hiroyuki wrote: > > > > > > > > + pm.pos = 0; > > > + start_vaddr += PAGEMAP_WALK_SIZE; > > > + end = start_vaddr + PAGEMAP_WALK_SIZE; > > > > Sigh...this is bad.. > > > > == > > From: KAMEZAWA Hiroyuki > > > > In initial design, walk_page_range() was designed just for walking page table and > > it didn't require mmap_sem. Now, find_vma() etc.. are used in walk_page_range() > > and we need mmap_sem around it. > > This looks pretty reasonable. However, it also looks very similar to my > first version of pagemap (which started with double-buffering). It's > going to need re-testing to make sure it hasn't reintroduced any > wrapping, alignment, or off-by-one bugs that have already been ironed > out once or twice. OK, I'm looking for your test result. :) Thanks matt for your contribution! -- 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/