Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751850AbaLXQi1 (ORCPT ); Wed, 24 Dec 2014 11:38:27 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:34616 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751340AbaLXQi0 (ORCPT ); Wed, 24 Dec 2014 11:38:26 -0500 Date: Wed, 24 Dec 2014 17:38:23 +0100 From: Pavel Machek To: kernel list Subject: DRAM unreliable under specific access patern Message-ID: <20141224163823.GA17035@amd> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! It seems that it is easy to induce DRAM bit errors by doing repeated reads from adjacent memory cells on common hw. Details are at https://www.ece.cmu.edu/~safari/pubs/kim-isca14.pdf . Older memory modules seem to work better, and ECC should detect this. Paper has inner loop that should trigger this. Workarounds seem to be at hardware level, and tricky, too. Does anyone have implementation of detector? Any ideas how to work around it in software? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/