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=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 2BFE7C4321D for ; Thu, 23 Aug 2018 08:01:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E4D1821480 for ; Thu, 23 Aug 2018 08:00:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E4D1821480 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728778AbeHWL3U (ORCPT ); Thu, 23 Aug 2018 07:29:20 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:44158 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727623AbeHWL3U (ORCPT ); Thu, 23 Aug 2018 07:29:20 -0400 Received: from localhost (5355525A.cm-6-6b.dynamic.ziggo.nl [83.85.82.90]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 9C888C49; Thu, 23 Aug 2018 08:00:41 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Myron Stowe , Bjorn Helgaas , Keith Busch , Sinan Kaya , Dongdong Liu , Jon Mason Subject: [PATCH 4.4 76/79] PCI: Skip MPS logic for Virtual Functions (VFs) Date: Thu, 23 Aug 2018 09:53:52 +0200 Message-Id: <20180823074924.155579322@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180823074918.641878835@linuxfoundation.org> References: <20180823074918.641878835@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Myron Stowe commit 3dbe97efe8bf450b183d6dee2305cbc032e6b8a4 upstream. PCIe r4.0, sec 9.3.5.4, "Device Control Register", shows both Max_Payload_Size (MPS) and Max_Read_request_Size (MRRS) to be 'RsvdP' for VFs. Just prior to the table it states: "PF and VF functionality is defined in Section 7.5.3.4 except where noted in Table 9-16. For VF fields marked 'RsvdP', the PF setting applies to the VF." All of which implies that with respect to Max_Payload_Size Supported (MPSS), MPS, and MRRS values, we should not be paying any attention to the VF's fields, but rather only to the PF's. Only looking at the PF's fields also logically makes sense as it's the sole physical interface to the PCIe bus. Link: https://bugzilla.kernel.org/show_bug.cgi?id=200527 Fixes: 27d868b5e6cf ("PCI: Set MPS to match upstream bridge") Signed-off-by: Myron Stowe Signed-off-by: Bjorn Helgaas Cc: stable@vger.kernel.org # 4.3+ Cc: Keith Busch Cc: Sinan Kaya Cc: Dongdong Liu Cc: Jon Mason Signed-off-by: Greg Kroah-Hartman --- drivers/pci/probe.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1338,6 +1338,10 @@ static void pci_configure_mps(struct pci if (!pci_is_pcie(dev) || !bridge || !pci_is_pcie(bridge)) return; + /* MPS and MRRS fields are of type 'RsvdP' for VFs, short-circuit out */ + if (dev->is_virtfn) + return; + mps = pcie_get_mps(dev); p_mps = pcie_get_mps(bridge);