From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761080AbZDGPV7 (ORCPT ); Tue, 7 Apr 2009 11:21:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759333AbZDGPKL (ORCPT ); Tue, 7 Apr 2009 11:10:11 -0400 Received: from one.firstfloor.org ([213.235.205.2]:41298 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759317AbZDGPKK (ORCPT ); Tue, 7 Apr 2009 11:10:10 -0400 From: Andi Kleen References: <20090407509.382219156@firstfloor.org> In-Reply-To: <20090407509.382219156@firstfloor.org> To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org Subject: [PATCH] [8/16] POISON: Add various poison checks in mm/memory.c Message-Id: <20090407151005.4E24B1D046D@basil.firstfloor.org> Date: Tue, 7 Apr 2009 17:10:05 +0200 (CEST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Bail out early when poisoned pages are found in page fault handling. Since they are poisoned they should not be mapped freshly into processes. This is generally handled in the same way as OOM, just a different error code is returned to the architecture code. Signed-off-by: Andi Kleen --- mm/memory.c | 7 +++++++ 1 file changed, 7 insertions(+) Index: linux/mm/memory.c =================================================================== --- linux.orig/mm/memory.c 2009-04-07 16:39:39.000000000 +0200 +++ linux/mm/memory.c 2009-04-07 16:39:39.000000000 +0200 @@ -2560,6 +2560,10 @@ goto oom; __SetPageUptodate(page); + /* Kludge for now until we take poisoned pages out of the free lists */ + if (unlikely(PagePoison(page))) + return VM_FAULT_POISON; + if (mem_cgroup_newpage_charge(page, mm, GFP_KERNEL)) goto oom_free_page; @@ -2625,6 +2629,9 @@ if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE))) return ret; + if (unlikely(PagePoison(vmf.page))) + return VM_FAULT_POISON; + /* * For consistency in subsequent calls, make the faulted page always * locked.