Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759238AbZFISuU (ORCPT ); Tue, 9 Jun 2009 14:50:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752290AbZFISuJ (ORCPT ); Tue, 9 Jun 2009 14:50:09 -0400 Received: from ganesha.gnumonks.org ([213.95.27.120]:41356 "EHLO ganesha.gnumonks.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751467AbZFISuI (ORCPT ); Tue, 9 Jun 2009 14:50:08 -0400 Date: Wed, 10 Jun 2009 02:45:52 +0800 From: Harald Welte To: Chuck Ebbert Cc: Herbert Xu , linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, Sebastian Andrzej Siewior Subject: Re: [patch 0/3] crypto: padlock-aes: enable on VIA Nano Message-ID: <20090609184552.GL5304@prithivi.gnumonks.org> References: <20090609103533.0c334594@dhcp-100-2-144.bos.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090609103533.0c334594@dhcp-100-2-144.bos.redhat.com> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1542 Lines: 34 On Tue, Jun 09, 2009 at 10:35:33AM -0400, Chuck Ebbert wrote: > The VIA Nano has a bug that makes the padlock unit fetch extra data > during encryption operations. Add workarounds for that, and enable > the driver on x86_64. Thanks! Where did you get the errata from, and what kind of document / revision is it? I have not seen that document so far. I've asked Centaur to confirm the errata, also inquired whether there will be a microcode update or a new stepping to fix it. If yes, we should add proper checks to the workaround to make sure it's only enabled when we need it. Out of curiosity: Only the ACE (crypto) is affected, not PHE (hashing)? I'll also put on my todo list to do some actual benchmarking to determine how much impact this bug has. I expect especially for storage encryption, many crypto operations will be page aligned and thus need the extra memcpy :( p.s.: the patch to enable padlock on x86_64 is already in the crypto-dev tree, as far as I know. Interestingly, I have not observed this problem so far, despite running dm-crypt on a nano for quite some time. Cheers, -- - Harald Welte http://linux.via.com.tw/ ============================================================================ VIA Free and Open Source Software Liaison -- 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/