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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 E4623C17440 for ; Sun, 10 Nov 2019 02:50:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BAF6E22794 for ; Sun, 10 Nov 2019 02:50:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573354228; bh=h18vsG2/dOzyz5ekVxrrjJAtpSd/yKL1s/yBtgCB0t8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=p0qYhDeMNPM41DXouFLb/fbaPichBpXndFvyVn6wVP30TkjlmFVCYN0+bjPqD6wcR eqb7YfrKv4h/pxNAT+ZiXuJTYqnOEk4rhxrZtZO/HFKmM5vQR+qeai46bo01y8XEcr 0lYOAL+bTjCJLHnK1XfaX2HCgbsmaqOcu9VgD9yA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729702AbfKJCu1 (ORCPT ); Sat, 9 Nov 2019 21:50:27 -0500 Received: from mail.kernel.org ([198.145.29.99]:60714 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729598AbfKJCuA (ORCPT ); Sat, 9 Nov 2019 21:50:00 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 225F422581; Sun, 10 Nov 2019 02:49:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573354199; bh=h18vsG2/dOzyz5ekVxrrjJAtpSd/yKL1s/yBtgCB0t8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XetK2v631T899r1KLDoJgZpjF8fEEJjDCD6Wycr1vBNDvS/ipbsVHSYeM070+T0OY Cw0Kg0Z2b5t8QpJxdHAl1luZM8UR4oC5GAovBDQkZQe47r+h1OIHOx95b6RvdqMvm5 kiw9KrOW6YrGcoDzIBa+HNPu34ZT2dXQCWt6Kr/Y= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Alex Williamson , Gage Eads , Ashok Raj , Sasha Levin , kvm@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 44/66] vfio/pci: Mask buggy SR-IOV VF INTx support Date: Sat, 9 Nov 2019 21:48:23 -0500 Message-Id: <20191110024846.32598-44-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191110024846.32598-1-sashal@kernel.org> References: <20191110024846.32598-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alex Williamson [ Upstream commit db04264fe9bc0f2b62e036629f9afb530324b693 ] The SR-IOV spec requires that VFs must report zero for the INTx pin register as VFs are precluded from INTx support. It's much easier for the host kernel to understand whether a device is a VF and therefore whether a non-zero pin register value is bogus than it is to do the same in userspace. Override the INTx count for such devices and virtualize the pin register to provide a consistent view of the device to the user. As this is clearly a spec violation, warn about it to support hardware validation, but also provide a known whitelist as it doesn't do much good to continue complaining if the hardware vendor doesn't plan to fix it. Known devices with this issue: 8086:270c Tested-by: Gage Eads Reviewed-by: Ashok Raj Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin --- drivers/vfio/pci/vfio_pci.c | 8 ++++++-- drivers/vfio/pci/vfio_pci_config.c | 27 +++++++++++++++++++++++++++ 2 files changed, 33 insertions(+), 2 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index a1a712d18e028..da3f0ed18c769 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -426,10 +426,14 @@ static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type) { if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) { u8 pin; + + if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) || + vdev->nointx || vdev->pdev->is_virtfn) + return 0; + pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin); - if (IS_ENABLED(CONFIG_VFIO_PCI_INTX) && !vdev->nointx && pin) - return 1; + return pin ? 1 : 0; } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) { u8 pos; u16 flags; diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c index 06a20ea183dd6..84905d074c4ff 100644 --- a/drivers/vfio/pci/vfio_pci_config.c +++ b/drivers/vfio/pci/vfio_pci_config.c @@ -1608,6 +1608,15 @@ static int vfio_ecap_init(struct vfio_pci_device *vdev) return 0; } +/* + * Nag about hardware bugs, hopefully to have vendors fix them, but at least + * to collect a list of dependencies for the VF INTx pin quirk below. + */ +static const struct pci_device_id known_bogus_vf_intx_pin[] = { + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x270c) }, + {} +}; + /* * For each device we allocate a pci_config_map that indicates the * capability occupying each dword and thus the struct perm_bits we @@ -1673,6 +1682,24 @@ int vfio_config_init(struct vfio_pci_device *vdev) if (pdev->is_virtfn) { *(__le16 *)&vconfig[PCI_VENDOR_ID] = cpu_to_le16(pdev->vendor); *(__le16 *)&vconfig[PCI_DEVICE_ID] = cpu_to_le16(pdev->device); + + /* + * Per SR-IOV spec rev 1.1, 3.4.1.18 the interrupt pin register + * does not apply to VFs and VFs must implement this register + * as read-only with value zero. Userspace is not readily able + * to identify whether a device is a VF and thus that the pin + * definition on the device is bogus should it violate this + * requirement. We already virtualize the pin register for + * other purposes, so we simply need to replace the bogus value + * and consider VFs when we determine INTx IRQ count. + */ + if (vconfig[PCI_INTERRUPT_PIN] && + !pci_match_id(known_bogus_vf_intx_pin, pdev)) + pci_warn(pdev, + "Hardware bug: VF reports bogus INTx pin %d\n", + vconfig[PCI_INTERRUPT_PIN]); + + vconfig[PCI_INTERRUPT_PIN] = 0; /* Gratuitous for good VFs */ } if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) || vdev->nointx) -- 2.20.1