Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946302AbWJSSKX (ORCPT ); Thu, 19 Oct 2006 14:10:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1946304AbWJSSKX (ORCPT ); Thu, 19 Oct 2006 14:10:23 -0400 Received: from smtp101.mail.mud.yahoo.com ([209.191.85.211]:16800 "HELO smtp101.mail.mud.yahoo.com") by vger.kernel.org with SMTP id S1946302AbWJSSKW (ORCPT ); Thu, 19 Oct 2006 14:10:22 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=oyv6R67Pa1B9O2xHduUJ8P8bbaNKIg8K6GCxGjFURHz0X0TnGnCG+QiCrGhvEUmXliO7dpZ3PU0/zr3iTTOv5F/X4zzPViYe+pFmrTulcgx/GYbZP+ngBG4QjGgAU3LEk/GojF1g4BVE/MAhXTl4z3+kEqhBfqUF5rlOCNwLT6s= ; Message-ID: <4537BF8A.9040004@yahoo.com.au> Date: Fri, 20 Oct 2006 04:10:18 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.12) Gecko/20051007 Debian/1.7.12-1 X-Accept-Language: en MIME-Version: 1.0 To: Carsten Otte CC: Andrew Morton , Cedric Le Goater , "Rafael J. Wysocki" , Gabriel C , linux-kernel@vger.kernel.org Subject: Re: 2.6.19-rc2-mm1 References: <20061016230645.fed53c5b.akpm@osdl.org> <45367210.4040507@googlemail.com> <200610182118.31371.rjw@sisk.pl> <4536818E.3060505@fr.ibm.com> <453683A6.9090106@yahoo.com.au> <45368E0A.1030503@fr.ibm.com> <20061018152346.0486b6bc.akpm@osdl.org> <4537A263.4090601@freenet.de> In-Reply-To: <4537A263.4090601@freenet.de> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1105 Lines: 28 Carsten Otte wrote: > Andrew Morton wrote: > >> The page we're writing into isn't locked, so there's no deadlock afaict. >> >> But then, I forget how xip works. Carsten, is it actually being used for >> anything? >> > > The comment may be superfluous. I did not quite understand the deadlock > condition refered to by the comment in filemap, therefore I cut&pasted > it over. I will send a patch that removes it. Yes, it wasn't a good comment. Basically we can't hold the page lock and then enter the page fault handler. mm-fix-pagecache-write-deadlocks.patch has quite a lot of comments to explain it. I don't believe filemap_xip holds the page lock, so you don't need to do the atomic copy, and you don't need to do the fault_in_pages_readable. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com - 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/