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 ESMTP id 8A8026B0055 for ; Tue, 9 Jun 2009 05:52:49 -0400 (EDT) Date: Tue, 9 Jun 2009 12:25:04 +0200 From: Nick Piggin Subject: Re: [PATCH] [6/16] HWPOISON: Add various poison checks in mm/memory.c Message-ID: <20090609102504.GH14820@wotan.suse.de> References: <20090603846.816684333@firstfloor.org> <20090603184639.1933B1D028F@basil.firstfloor.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090603184639.1933B1D028F@basil.firstfloor.org> Sender: owner-linux-mm@kvack.org To: Andi Kleen Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, fengguang.wu@intel.com List-ID: On Wed, Jun 03, 2009 at 08:46:38PM +0200, Andi Kleen wrote: > > 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. > > Signed-off-by: Andi Kleen > > --- > mm/memory.c | 3 +++ > 1 file changed, 3 insertions(+) > > Index: linux/mm/memory.c > =================================================================== > --- linux.orig/mm/memory.c 2009-06-03 19:36:23.000000000 +0200 > +++ linux/mm/memory.c 2009-06-03 19:36:23.000000000 +0200 > @@ -2797,6 +2797,9 @@ > if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE))) > return ret; > > + if (unlikely(PageHWPoison(vmf.page))) > + return VM_FAULT_HWPOISON; Again, it would be nice if you just worry about this in your MCE handler and don't sprinkle things like this in fastpaths. > + > /* > * For consistency in subsequent calls, make the faulted page always > * locked. -- 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