From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756689AbZE1Koa (ORCPT ); Thu, 28 May 2009 06:44:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753135AbZE1KoX (ORCPT ); Thu, 28 May 2009 06:44:23 -0400 Received: from one.firstfloor.org ([213.235.205.2]:59493 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750983AbZE1KoW (ORCPT ); Thu, 28 May 2009 06:44:22 -0400 Date: Thu, 28 May 2009 12:51:03 +0200 From: Andi Kleen To: Wu Fengguang Cc: Andi Kleen , Nick Piggin , "hugh@veritas.com" , "riel@redhat.com" , "akpm@linux-foundation.org" , "chris.mason@oracle.com" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" Subject: Re: [PATCH] [13/16] HWPOISON: The high level memory error handler in the VM v3 Message-ID: <20090528105103.GG1065@one.firstfloor.org> References: <200905271012.668777061@firstfloor.org> <20090527201239.C2C9C1D0294@basil.firstfloor.org> <20090528082616.GG6920@wotan.suse.de> <20090528095934.GA10678@localhost> <20090528101111.GE1065@one.firstfloor.org> <20090528103300.GA15133@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090528103300.GA15133@localhost> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 28, 2009 at 06:33:00PM +0800, Wu Fengguang wrote: > > > > You haven't waited on writeback here AFAIKS, and have you > > > > *really* verified it is safe to call delete_from_swap_cache? > > > > > > Good catch. I'll soon submit patches for handling the under > > > read/write IO pages. In this patchset they are simply ignored. > > > > Yes, we assume the IO device does something sensible with the poisoned > > cache lines and aborts. Later we can likely abort IO requests in a early > > stage on the Linux, but that's more advanced. > > > > The question is if we need to wait on writeback for correctness? > > Not necessary. Because I'm going to add a me_writeback() handler. Ok but without it. Let's assume me_writeback() is in the future. I'm mainly interested in correctness (as in not crashing) of this version now. Also writeback seems to be only used by nfs/afs/nilfs2, not in the normal case, unless I'm misreading the code. The nilfs2 case seems weird, I haven't completely read that. > Then the writeback pages simply won't reach here. And it won't > magically go into writeback state, since the page has been locked. But since we take the page lock they should not be in writeback anyways, no? -Andi -- ak@linux.intel.com -- Speaking for myself only.