From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932070Ab3AXT5u (ORCPT ); Thu, 24 Jan 2013 14:57:50 -0500 Received: from mail.skyhub.de ([78.46.96.112]:60287 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755103Ab3AXT5n (ORCPT ); Thu, 24 Jan 2013 14:57:43 -0500 Date: Thu, 24 Jan 2013 21:00:34 +0100 From: Borislav Petkov To: suravee.suthikulpanit@amd.com Cc: iommu@lists.linux-foundation.org, joro@8bytes.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V4] IOMMU, AMD Family15h Model10-1Fh erratum 746 Workaround Message-ID: <20130124200034.GM13463@pd.tnic> Mail-Followup-To: Borislav Petkov , suravee.suthikulpanit@amd.com, iommu@lists.linux-foundation.org, joro@8bytes.org, linux-kernel@vger.kernel.org References: <1359055073-29732-1-git-send-email-suravee.suthikulpanit@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1359055073-29732-1-git-send-email-suravee.suthikulpanit@amd.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 24, 2013 at 01:17:53PM -0600, suravee.suthikulpanit@amd.com wrote: > From: Suravee Suthikulpanit > > The IOMMU may stop processing page translations due to a perceived lack > of credits for writing upstream peripheral page service request (PPR) > or event logs. If the L2B miscellaneous clock gating feature is enabled > the IOMMU does not properly register credits after the log request has > completed, leading to a potential system hang. > > BIOSes are supposed to disable L2B micellaneous clock gating by setting > L2_L2B_CK_GATE_CONTROL[CKGateL2BMiscDisable](D0F2xF4_x90[2]) = 1b. This > patch corrects that for those which do not enable this workaround. > > Signed-off-by: Suravee Suthikulpanit Acked-by: Borislav Petkov Thanks for the good work. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --