From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 92661C4CEC4 for ; Wed, 18 Sep 2019 16:46:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6699A21920 for ; Wed, 18 Sep 2019 16:46:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387734AbfIRQqx (ORCPT ); Wed, 18 Sep 2019 12:46:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33482 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387733AbfIRQqw (ORCPT ); Wed, 18 Sep 2019 12:46:52 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 53ECFEC524; Wed, 18 Sep 2019 16:46:52 +0000 (UTC) Received: from x1.home (ovpn-118-102.phx2.redhat.com [10.3.118.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id C3041100197A; Wed, 18 Sep 2019 16:46:51 +0000 (UTC) Date: Wed, 18 Sep 2019 10:46:51 -0600 From: Alex Williamson To: Andrew Murray Cc: Steffen Liebergeld , linux-pci@vger.kernel.org, Bjorn Helgaas , "Raj, Ashok" Subject: Re: [PATCH] PCI: quirks: Fix register location for UPDCR Message-ID: <20190918104651.66535375@x1.home> In-Reply-To: <20190918120917.GF9720@e119886-lin.cambridge.arm.com> References: <054ef65b-07de-7625-ebcb-f5ce64bc2726@kernkonzept.com> <20190918104213.GD9720@e119886-lin.cambridge.arm.com> <8da75cab-d3d4-14aa-1113-087d4a868072@kernkonzept.com> <20190918120917.GF9720@e119886-lin.cambridge.arm.com> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Wed, 18 Sep 2019 16:46:52 +0000 (UTC) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, 18 Sep 2019 13:09:18 +0100 Andrew Murray wrote: > On Wed, Sep 18, 2019 at 02:02:59PM +0200, Steffen Liebergeld wrote: > > On 18/09/2019 12:42, Andrew Murray wrote: > > > On Tue, Sep 17, 2019 at 08:07:13PM +0200, Steffen Liebergeld wrote: > > >> According to documentation [0] the correct offset for the > > >> Upstream Peer Decode Configuration Register (UPDCR) is 0x1014. > > >> It was previously defined as 0x1114. This patch fixes it. > > >> > > >> [0] > > >> https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/4th-gen-core-family-mobile-i-o-datasheet.pdf > > >> (page 325) > > >> > > >> Signed-off-by: Steffen Liebergeld > > > > > > You may also like to add: > > > > > > Fixes: d99321b63b1f ("PCI: Enable quirks for PCIe ACS on Intel PCH root ports") > > > Reviewed-by: Andrew Murray > > > > > > As well as CC'ing stable. > > > > Ok. Thank you. > > > > > I guess the side effect of this bug is that we claim to have peer > > > isolation when we do not. This fix ensures that we get the advertised > > > isolation. > > Yes, that is also my understanding. Should I explain that in the commit > > message? > > I think something similar to that would be helpful. This is unfortunate, but my initial impression is that this may have just been a typo that slipped by everyone. It's difficult to actually test for isolation. Maybe someone from Intel could review this. Also, Steffen discussed this with me prior to posting and I believe this is untested, so while trivial from inspection, it would be preferable to know that some sample of hardware doesn't fall over as a result. Thanks, Alex