From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755916AbZIKSsh (ORCPT ); Fri, 11 Sep 2009 14:48:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755904AbZIKSsf (ORCPT ); Fri, 11 Sep 2009 14:48:35 -0400 Received: from one.firstfloor.org ([213.235.205.2]:54010 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755758AbZIKSsc (ORCPT ); Fri, 11 Sep 2009 14:48:32 -0400 From: Andi Kleen References: <20090911848.933193846@firstfloor.org> In-Reply-To: <20090911848.933193846@firstfloor.org> To: linux-kernel@vger.kernel.org Subject: [PATCH] [6/21] HWPOISON: Add various poison checks in mm/memory.c v2 Message-Id: <20090911184835.1BC87B1757@basil.firstfloor.org> Date: Fri, 11 Sep 2009 20:48:35 +0200 (CEST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Bail out early when hardware poisoned pages are found in page fault handling. Since they are poisoned they should not be mapped freshly into processes, because that would cause another (potentially deadly) machine check This is generally handled in the same way as OOM, just a different error code is returned to the architecture code. v2: Do a page unlock if needed (Fengguang Wu) Signed-off-by: Andi Kleen --- mm/memory.c | 6 ++++++ 1 file changed, 6 insertions(+) Index: linux/mm/memory.c =================================================================== --- linux.orig/mm/memory.c +++ linux/mm/memory.c @@ -2711,6 +2711,12 @@ static int __do_fault(struct mm_struct * if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE))) return ret; + if (unlikely(PageHWPoison(vmf.page))) { + if (ret & VM_FAULT_LOCKED) + unlock_page(vmf.page); + return VM_FAULT_HWPOISON; + } + /* * For consistency in subsequent calls, make the faulted page always * locked.