From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with SMTP id 695FC5F0001 for ; Mon, 13 Apr 2009 09:18:51 -0400 (EDT) Date: Mon, 13 Apr 2009 21:18:42 +0800 From: Wu Fengguang Subject: Re: [PATCH] [0/16] POISON: Intro Message-ID: <20090413131842.GA8640@localhost> References: <20090407509.382219156@firstfloor.org> <20090407224709.742376ff.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090407224709.742376ff.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: Andi Kleen , linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org List-ID: On Tue, Apr 07, 2009 at 10:47:09PM -0700, Andrew Morton wrote: > On Tue, 7 Apr 2009 17:09:56 +0200 (CEST) Andi Kleen wrote: > > > Upcoming Intel CPUs have support for recovering from some memory errors. This > > requires the OS to declare a page "poisoned", kill the processes associated > > with it and avoid using it in the future. This patchkit implements > > the necessary infrastructure in the VM. > > Seems that this feature is crying out for a testing framework (perhaps > it already has one?). A simplistic approach would be > > echo some-pfn > /proc/bad-pfn-goes-here How about reusing the /proc/kpageflags interface? i.e. make it writable. It may sound crazy and way too _hacky_, but it is possible to attach actions to the state transition of some page flags ;) PG_poison 0 => 1: call memory_failure() PG_active 1 => 0: move page into inactive lru PG_unevictable 1 => 0: move page out of unevictable lru PG_swapcache 1 => 0: remove page from swap cache PG_lru 1 => 0: reclaim page Thanks, Fengguang > A slightly more sophisticated version might do the deed from within a > timer interrupt, just to get a bit more coverage. > > -- > 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 -- 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