From patchwork Tue Jun 20 07:18:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ani Sinha X-Patchwork-Id: 13285240 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2E512EB64D7 for ; Tue, 20 Jun 2023 07:19:10 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qBVdH-0004L8-7Q; Tue, 20 Jun 2023 03:18:32 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qBVdE-0004KN-HH for qemu-devel@nongnu.org; Tue, 20 Jun 2023 03:18:28 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qBVdC-0006GC-Nt for qemu-devel@nongnu.org; Tue, 20 Jun 2023 03:18:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1687245504; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=wx6OtQTzdSiC1EUBAQtfYo+awyRfge7HDnOsUegRGlo=; b=h3QP1UTo0bn63xiZJb98SBCbKdoGdW+w9XcD64Y6aicfhC1Tn+yj/9Uu8PLJ+wlyDRKuP4 3IjMHx/5O7zmvT44W3/L26Q7Ac1lSPQTdFMBG6kbtW1pRav3rgqLFcNArZqlomc2PzU/xj 6Uoq8DbhtRCi1IVkAfWjJ3pnMPbACs8= Received: from mail-pg1-f199.google.com (mail-pg1-f199.google.com [209.85.215.199]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-382-nsFbXBaGOSi7UxWDGfkPgw-1; Tue, 20 Jun 2023 03:18:21 -0400 X-MC-Unique: nsFbXBaGOSi7UxWDGfkPgw-1 Received: by mail-pg1-f199.google.com with SMTP id 41be03b00d2f7-5538f216c7aso943828a12.0 for ; Tue, 20 Jun 2023 00:18:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687245500; x=1689837500; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=wx6OtQTzdSiC1EUBAQtfYo+awyRfge7HDnOsUegRGlo=; b=jlsKJw5PVMvgm3GssLILRIdDD79lY8Zdp93yYXdFYXJb2ZA/eWDrnSwsrJnnAMm1iI GoB9UWWgCXua5nQ3vI9g6yZft/+wbMh4AQ8RxtiNPt8puJpnpihSY+XaLpBoYUc5hFDk y9wansRM6dOlAHgGzV7nFO9got7Y0qwXGmYn064/Gs3osoUXzLS3IC86I0M2VZv3yrjs hfN94JbkRZZBBUCQ7BIGeCLgA8e+pnXpXZz+aUMFCY+EMAAk7dwkkPWwa0ln4T6CnI1n j25TS6/sTtJvTrKvVnYHNdF4swm0qkeTxR+Ns6JjZfZzkXSMB5g7HcCCSLEZTwTjCAJq x2Ew== X-Gm-Message-State: AC+VfDzbPWmCOfK8LDJBQII1MZWW3K6Ty7i+bQsqmIjB0SL6ZiBY/EuH FqLllc6P/NGO9pfeFhMLdXYgN9Mt7OqWxpfJ4E1vNuarYuNYPRLMsETawQUYcxAAP78TNaKCs6n qqAqEFY9gviz74yc= X-Received: by 2002:a05:6a20:3d85:b0:118:a48:8977 with SMTP id s5-20020a056a203d8500b001180a488977mr8992337pzi.3.1687245499926; Tue, 20 Jun 2023 00:18:19 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ4AQgOsORLwFCZpDrqW9VRAaun31SmfCtYitGqonoEtfib21lpOXLsngflfttD22QTwKJLTuA== X-Received: by 2002:a05:6a20:3d85:b0:118:a48:8977 with SMTP id s5-20020a056a203d8500b001180a488977mr8992321pzi.3.1687245499480; Tue, 20 Jun 2023 00:18:19 -0700 (PDT) Received: from localhost.localdomain ([116.72.143.94]) by smtp.googlemail.com with ESMTPSA id io20-20020a17090312d400b001ac38343438sm903669plb.176.2023.06.20.00.18.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 20 Jun 2023 00:18:18 -0700 (PDT) From: Ani Sinha To: "Michael S. Tsirkin" , Marcel Apfelbaum Cc: Ani Sinha , jusual@redhat.com, imammedo@redhat.com, qemu-devel@nongnu.org Subject: [PATCH v4] hw/pci: enforce use of slot only slot 0 when devices have an upstream PCIE port Date: Tue, 20 Jun 2023 12:48:05 +0530 Message-Id: <20230620071805.4400-1-anisinha@redhat.com> X-Mailer: git-send-email 2.39.1 MIME-Version: 1.0 Received-SPF: pass client-ip=170.10.133.124; envelope-from=anisinha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org When a device has an upstream PCIE port, we can only use slot 0. Non-zero slots are invalid. This change ensures that we throw an error if the user tries to hotplug a device with an upstream PCIE port to a non-zero slot. CC: jusual@redhat.com CC: imammedo@redhat.com Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2128929 Signed-off-by: Ani Sinha --- hw/pci/pci.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) changelog: v2: addressed issue with multifunction pcie root ports. Should allow hotplug on functions other than function 0. v3: improved commit message. v4: improve commit message and code comments further. Some more improvements might come in v5. No claims made here that this is the final one :-) diff --git a/hw/pci/pci.c b/hw/pci/pci.c index bf38905b7d..30ce6a78cb 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -64,6 +64,7 @@ bool pci_available = true; static char *pcibus_get_dev_path(DeviceState *dev); static char *pcibus_get_fw_dev_path(DeviceState *dev); static void pcibus_reset(BusState *qbus); +static bool pcie_has_upstream_port(PCIDevice *dev); static Property pci_props[] = { DEFINE_PROP_PCI_DEVFN("addr", PCIDevice, devfn, -1), @@ -1182,6 +1183,11 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, } else if (dev->hotplugged && !pci_is_vf(pci_dev) && pci_get_function_0(pci_dev)) { + /* + * populating function 0 triggers a bus scan from the guest that + * exposes other non-zero functions. Hence we need to ensure that + * function 0 wasn't added yet. + */ error_setg(errp, "PCI: slot %d function 0 already occupied by %s," " new func %s cannot be exposed to guest.", PCI_SLOT(pci_get_function_0(pci_dev)->devfn), @@ -1189,6 +1195,18 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, name); return NULL; + } else if (dev->hotplugged && + !pci_is_vf(pci_dev) && + pcie_has_upstream_port(pci_dev) && PCI_SLOT(devfn)) { + /* + * If the device has an upstream PCIE port, like a pcie root port, + * we only support functions on slot 0. + */ + error_setg(errp, "PCI: slot %d is not valid for %s," + " only functions on slot 0 is supported for devices" + " with an upstream PCIE port.", + PCI_SLOT(devfn), name); + return NULL; } pci_dev->devfn = devfn;