From patchwork Tue Jul 25 14:55:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Tokarev X-Patchwork-Id: 1812651 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4R9KqY1HWWz1yYc for ; Wed, 26 Jul 2023 00:56:41 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qOJSD-0002V5-2Y; Tue, 25 Jul 2023 10:56:01 -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 1qOJS4-0002PU-79; Tue, 25 Jul 2023 10:55:53 -0400 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qOJS2-0000D5-J1; Tue, 25 Jul 2023 10:55:51 -0400 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 40B3E161C5; Tue, 25 Jul 2023 17:55:38 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id D56A219540; Tue, 25 Jul 2023 17:55:35 +0300 (MSK) Received: (nullmailer pid 3375818 invoked by uid 1000); Tue, 25 Jul 2023 14:55:34 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-trivial@nongnu.org, Ani Sinha , mst@redhat.com, mjt@tls.msk.ru Subject: [PULL 7/8] hw/pci: add comment to explain checking for available function 0 in pci hotplug Date: Tue, 25 Jul 2023 17:55:31 +0300 Message-Id: <67d045a0ef5b9c5f871c3a1d87325a8a42d2b9d5.1690294956.git.mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Ani Sinha This change is cosmetic. A comment is added explaining why we need to check for the availability of function 0 when we hotplug a device. CC: mst@redhat.com CC: mjt@tls.msk.ru Signed-off-by: Ani Sinha Signed-off-by: Michael Tokarev --- hw/pci/pci.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/hw/pci/pci.c b/hw/pci/pci.c index 784c02a182..b8d22e2e74 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -1183,9 +1183,14 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCI_SLOT(devfn), PCI_FUNC(devfn), name, bus->devices[devfn]->name, bus->devices[devfn]->qdev.id); return NULL; - } else if (dev->hotplugged && - !pci_is_vf(pci_dev) && - pci_get_function_0(pci_dev)) { + } /* + * Populating function 0 triggers a scan from the guest that + * exposes other non-zero functions. Hence we need to ensure that + * function 0 wasn't added yet. + */ + else if (dev->hotplugged && + !pci_is_vf(pci_dev) && + pci_get_function_0(pci_dev)) { 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),