From patchwork Mon Mar 12 22:44:26 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Williamson X-Patchwork-Id: 10277625 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id F2405602BD for ; Mon, 12 Mar 2018 22:44:32 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DF8D928A7D for ; Mon, 12 Mar 2018 22:44:32 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D1E6628DAF; Mon, 12 Mar 2018 22:44:32 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5FF7328A7D for ; Mon, 12 Mar 2018 22:44:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751333AbeCLWo3 (ORCPT ); Mon, 12 Mar 2018 18:44:29 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36440 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751282AbeCLWo2 (ORCPT ); Mon, 12 Mar 2018 18:44:28 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2521A356CD; Mon, 12 Mar 2018 22:44:28 +0000 (UTC) Received: from w520.home (ovpn-117-203.phx2.redhat.com [10.3.117.203]) by smtp.corp.redhat.com (Postfix) with ESMTP id 876295D9C5; Mon, 12 Mar 2018 22:44:27 +0000 (UTC) Date: Mon, 12 Mar 2018 16:44:26 -0600 From: Alex Williamson To: Alexey Kardashevskiy Cc: kvm@vger.kernel.org, Casey Leedom , Ganesh GR , "Arjun V ." , Indranil Choudhury , Nirranjan Kirubaharan Subject: Re: [PATCH kernel] vfio: Print message about masking INTx only when it is known to be broken Message-ID: <20180312164426.68b3c422@w520.home> In-Reply-To: <20180309011736.41300-1-aik@ozlabs.ru> References: <20180309011736.41300-1-aik@ozlabs.ru> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Mon, 12 Mar 2018 22:44:28 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On Fri, 9 Mar 2018 12:17:36 +1100 Alexey Kardashevskiy wrote: > Commit 2170dd04316e ("vfio-pci: Mask INTx if a device is not capabable > of enabling it") is causing 'Masking broken INTx support' messages > every time when a PCI without INTx support is enabled. This message is > intended to appear when a device known for broken INTx is being enabled. > However the message also appears on IOV virtual functions where INTx > cannot possibly be enabled so saying that the "broken" support is masked > is not correct. > > This changes the message to only appear when the device advertises INTx > (via PCI_INTERRUPT_PIN != 0) but does not implement PCI 2.3 INTx masking. > > Fixes: 2170dd04316e ("vfio-pci: Mask INTx if a device is not capabable of enabling it") > Signed-off-by: Alexey Kardashevskiy > --- > drivers/vfio/pci/vfio_pci.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c > index b0f7594..7f2ec47 100644 > --- a/drivers/vfio/pci/vfio_pci.c > +++ b/drivers/vfio/pci/vfio_pci.c > @@ -245,7 +245,13 @@ static int vfio_pci_enable(struct vfio_pci_device *vdev) > > if (likely(!nointxmask)) { > if (vfio_pci_nointx(pdev)) { > - dev_info(&pdev->dev, "Masking broken INTx support\n"); > + u8 pin = 0; > + > + pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, > + &pin); > + if (pin) > + dev_info(&pdev->dev, > + "Masking broken INTx support\n"); > vdev->nointx = true; > pci_intx(pdev, 0); > } else Why don't we fix it at the location of the bug rather than after the fact? I don't see any reason to invoke the nointx handling for devices that don't actually support INTx. Thanks, Alex diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index ad18ed266dc0..34d463a0b4a5 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -192,6 +192,8 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev); */ static bool vfio_pci_nointx(struct pci_dev *pdev) { + u8 pin; + switch (pdev->vendor) { case PCI_VENDOR_ID_INTEL: switch (pdev->device) { @@ -207,7 +209,9 @@ static bool vfio_pci_nointx(struct pci_dev *pdev) } } - if (!pdev->irq) + pci_read_config_byte(pdev, PCI_INTERRUPT_PIN, &pin); + + if (pin && !pdev->irq) return true; return false;