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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 E8E6EC433E0 for ; Fri, 5 Feb 2021 12:46:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 90FF264DFD for ; Fri, 5 Feb 2021 12:46:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232238AbhBEMp5 (ORCPT ); Fri, 5 Feb 2021 07:45:57 -0500 Received: from stargate.chelsio.com ([12.32.117.8]:40605 "EHLO stargate.chelsio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232194AbhBEMnt (ORCPT ); Fri, 5 Feb 2021 07:43:49 -0500 Received: from localhost (kumbhalgarh.blr.asicdesigners.com [10.193.185.255]) by stargate.chelsio.com (8.13.8/8.13.8) with ESMTP id 115CgeqE030066; Fri, 5 Feb 2021 04:42:41 -0800 Date: Fri, 5 Feb 2021 18:12:41 +0530 From: Raju Rangoju To: Heiner Kallweit Cc: Jakub Kicinski , David Miller , Bjorn Helgaas , "linux-pci@vger.kernel.org" , "netdev@vger.kernel.org" , rahul.lakkireddy@chelsio.com Subject: Re: [PATCH net-next 1/4] PCI/VPD: Remove Chelsio T3 quirk Message-ID: <20210205124236.GA18529@chelsio.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Tuesday, February 02/02/21, 2021 at 21:35:55 +0100, Heiner Kallweit wrote: > cxgb3 driver doesn't use the PCI core code for VPD access, it has its own > implementation. Therefore we don't need a quirk for it in the core code. > > Signed-off-by: Heiner Kallweit > --- > drivers/pci/vpd.c | 13 ++++--------- > 1 file changed, 4 insertions(+), 9 deletions(-) > > diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c > index 7915d10f9..db86fe226 100644 > --- a/drivers/pci/vpd.c > +++ b/drivers/pci/vpd.c > @@ -628,22 +628,17 @@ static void quirk_chelsio_extend_vpd(struct pci_dev *dev) > { > int chip = (dev->device & 0xf000) >> 12; > int func = (dev->device & 0x0f00) >> 8; > - int prod = (dev->device & 0x00ff) >> 0; > > /* > - * If this is a T3-based adapter, there's a 1KB VPD area at offset > - * 0xc00 which contains the preferred VPD values. If this is a T4 or > - * later based adapter, the special VPD is at offset 0x400 for the > - * Physical Functions (the SR-IOV Virtual Functions have no VPD > - * Capabilities). The PCI VPD Access core routines will normally > + * If this is a T4 or later based adapter, the special VPD is at offset > + * 0x400 for the Physical Functions (the SR-IOV Virtual Functions have > + * no VPD Capabilities). The PCI VPD Access core routines will normally > * compute the size of the VPD by parsing the VPD Data Structure at > * offset 0x000. This will result in silent failures when attempting > * to accesses these other VPD areas which are beyond those computed > * limits. > */ > - if (chip == 0x0 && prod >= 0x20) > - pci_set_vpd_size(dev, 8192); The above quirk has been added by the following commit to fix VPD access issue in the guest VM. Wouldn't removing this quirk reopen the original issue? ---------------------------------------------------------- commit 1c7de2b4ff886a45fbd2f4c3d4627e0f37a9dd77 Author: Alexey Kardashevskiy Date: Mon Oct 24 18:04:17 2016 +1100 PCI: Enable access to non-standard VPD for Chelsio devices (cxgb3) There is at least one Chelsio 10Gb card which uses VPD area to store some non-standard blocks (example below). However pci_vpd_size() returns the length of the first block only assuming that there can be only one VPD "End Tag". Since 4e1a635552d3 ("vfio/pci: Use kernel VPD access functions"), VFIO blocks access beyond that offset, which prevents the guest "cxgb3" driver from probing the device. The host system does not have this problem as its driver accesses the config space directly without pci_read_vpd(). Add a quirk to override the VPD size to a bigger value. The maximum size is taken from EEPROMSIZE in drivers/net/ethernet/chelsio/cxgb3/common.h. We do not read the tag as the cxgb3 driver does as the driver supports writing to EEPROM/VPD and when it writes, it only checks for 8192 bytes boundary. The quirk is registered for all devices supported by the cxgb3 driver. This adds a quirk to the PCI layer (not to the cxgb3 driver) as the cxgb3 driver itself accesses VPD directly and the problem only exists with the vfio-pci driver (when cxgb3 is not running on the host and may not be even loaded) which blocks accesses beyond the first block of VPD data. However vfio-pci itself does not have quirks mechanism so we add it to PCI. This is the controller: Ethernet controller [0200]: Chelsio Communications Inc T310 10GbE Single Port Adapter [1425:0030] This is what I parsed from its VPD: === b'\x82*\x0010 Gigabit Ethernet-SR PCI Express Adapter\x90J\x00EC\x07D76809 FN\x0746K' 0000 Large item 42 bytes; name 0x2 Identifier String b'10 Gigabit Ethernet-SR PCI Express Adapter' 002d Large item 74 bytes; name 0x10 #00 [EC] len=7: b'D76809' #0a [FN] len=7: b'46K7897' #14 [PN] len=7: b'46K7897' #1e [MN] len=4: b'1037' #25 [FC] len=4: b'5769' #2c [SN] len=12: b'YL102035603V' #3b [NA] len=12: b'00145E992ED1' 007a Small item 1 bytes; name 0xf End Tag 0c00 Large item 16 bytes; name 0x2 Identifier String b'S310E-SR-X ' 0c13 Large item 234 bytes; name 0x10 #00 [PN] len=16: b'TBD ' #13 [EC] len=16: b'110107730D2 ' #26 [SN] len=16: b'97YL102035603V ' #39 [NA] len=12: b'00145E992ED1' #48 [V0] len=6: b'175000' #51 [V1] len=6: b'266666' #5a [V2] len=6: b'266666' #63 [V3] len=6: b'2000 ' #6c [V4] len=2: b'1 ' #71 [V5] len=6: b'c2 ' #7a [V6] len=6: b'0 ' #83 [V7] len=2: b'1 ' #88 [V8] len=2: b'0 ' #8d [V9] len=2: b'0 ' #92 [VA] len=2: b'0 ' #97 [RV] len=80: b's\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'... 0d00 Large item 252 bytes; name 0x11 #00 [VC] len=16: b'122310_1222 dp ' #13 [VD] len=16: b'610-0001-00 H1\x00\x00' #26 [VE] len=16: b'122310_1353 fp ' #39 [VF] len=16: b'610-0001-00 H1\x00\x00' #4c [RW] len=173: b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'... 0dff Small item 0 bytes; name 0xf End Tag 10f3 Large item 13315 bytes; name 0x62 !!! unknown item name 98: b'\xd0\x03\x00@`\x0c\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00' === Signed-off-by: Alexey Kardashevskiy Signed-off-by: Bjorn Helgaas --------------------------------------------- > - else if (chip >= 0x4 && func < 0x8) > + if (chip >= 0x4 && func < 0x8) > pci_set_vpd_size(dev, 2048); > } > > -- > 2.30.0 > >