From patchwork Thu Feb 24 17:44:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Igor Mammedov X-Patchwork-Id: 12759086 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 6F92AC433F5 for ; Thu, 24 Feb 2022 17:47:36 +0000 (UTC) Received: from localhost ([::1]:39176 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nNIDG-0003hp-1u for qemu-devel@archiver.kernel.org; Thu, 24 Feb 2022 12:47:34 -0500 Received: from eggs.gnu.org ([209.51.188.92]:39228) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nNIC2-0001lQ-93 for qemu-devel@nongnu.org; Thu, 24 Feb 2022 12:46:18 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:46073) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nNIBt-0002VQ-ED for qemu-devel@nongnu.org; Thu, 24 Feb 2022 12:46:17 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1645724758; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=dHYpuN/ALkxd3ga2HMxALEv4o/lFFAEjKJ81OR2oV/4=; b=Jr1twSYVHJ1/h7ZuDXXsA7hdFRuxh/wY2s4tugABnmxKrz9gvpwUQh/bvmPUSMslVhnMQJ CrLiuP96bgh+qhrns/pMArvVzBMqzj67IPsMu1VBBLvuRp8pS8S0wMx6GMvELmK1ijrhIr piEvDDoqAr3UkUDlzWVBZk0q9AJLlFM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-657-o0lNQ3VNPaaU0YHVo20y6g-1; Thu, 24 Feb 2022 12:45:57 -0500 X-MC-Unique: o0lNQ3VNPaaU0YHVo20y6g-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 61E54180FD73 for ; Thu, 24 Feb 2022 17:45:56 +0000 (UTC) Received: from dell-r430-03.lab.eng.brq.redhat.com (dell-r430-03.lab.eng.brq.redhat.com [10.37.153.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id D94F9710AC; Thu, 24 Feb 2022 17:45:41 +0000 (UTC) From: Igor Mammedov To: qemu-devel@nongnu.org Subject: [PATCH 2/4] pcie: update slot power status only is power control is enabled Date: Thu, 24 Feb 2022 12:44:09 -0500 Message-Id: <20220224174411.3296848-3-imammedo@redhat.com> In-Reply-To: <20220224174411.3296848-1-imammedo@redhat.com> References: <20220224174411.3296848-1-imammedo@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=imammedo@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.129.124; envelope-from=imammedo@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: , Cc: kraxel@redhat.com, mst@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" on creation a PCIDevice has power turned on at the end of pci_qdev_realize() however later on if PCIe slot isn't populated with any children it's power is turned off. It's fine if native hotplug is used as plug callback will power slot on among other things. However when ACPI hotplug is enabled it replaces native PCIe plug callbacks with ACPI specific ones (acpi_pcihp_device_*plug_cb) and as result slot stays powered off. It works fine as ACPI hotplug on guest side takes care of enumerating/initializing hotplugged device. But when later guest is migrated, call chain introduced by [1] pcie_cap_slot_post_load() -> pcie_cap_update_power() -> pcie_set_power_device() -> pci_set_power() -> pci_update_mappings() will disable earlier initialized BARs for the hotplugged device in powered off slot due to commit [2] which disables BARs if power is off. As result guest OS after migration will be very much confused [3], still thinking that it has working device, which isn't true anymore due to disabled BARs. Fix it by honoring PCI_EXP_SLTCAP_PCP and updating power status only if capability is enabled. Follow up patch will disable PCI_EXP_SLTCAP_PCP overriding COMPAT_PROP_PCP property when PCIe slot is under ACPI PCI hotplug control. See [3] for reproducer. 1) Fixes: commit d5daff7d312 (pcie: implement slot power control for pcie root ports) 2) commit 23786d13441 (pci: implement power state) 3) Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2053584 Signed-off-by: Igor Mammedov --- hw/pci/pcie.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c index d7d73a31e4..2339729a7c 100644 --- a/hw/pci/pcie.c +++ b/hw/pci/pcie.c @@ -383,10 +383,9 @@ static void pcie_cap_update_power(PCIDevice *hotplug_dev) if (sltcap & PCI_EXP_SLTCAP_PCP) { power = (sltctl & PCI_EXP_SLTCTL_PCC) == PCI_EXP_SLTCTL_PWR_ON; + pci_for_each_device(sec_bus, pci_bus_num(sec_bus), + pcie_set_power_device, &power); } - - pci_for_each_device(sec_bus, pci_bus_num(sec_bus), - pcie_set_power_device, &power); } /*