From patchwork Thu Jan 23 13:28:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Damien Hedde X-Patchwork-Id: 1228184 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: 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=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=greensocs.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; secure) header.d=greensocs.com header.i=@greensocs.com header.a=rsa-sha256 header.s=mail header.b=xwkg3cyr; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 483RSK5Zpyz9sSP for ; Fri, 24 Jan 2020 02:45:37 +1100 (AEDT) Received: from localhost ([::1]:59658 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iuefn-00089o-5L for incoming@patchwork.ozlabs.org; Thu, 23 Jan 2020 10:45:35 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:46959) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iucXL-00057k-Ve for qemu-devel@nongnu.org; Thu, 23 Jan 2020 08:28:45 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iucXJ-0003hF-Et for qemu-devel@nongnu.org; Thu, 23 Jan 2020 08:28:43 -0500 Received: from beetle.greensocs.com ([5.135.226.135]:56750) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iucXJ-0003ga-5X; Thu, 23 Jan 2020 08:28:41 -0500 Received: from crumble.bar.greensocs.com (crumble.bar.greensocs.com [172.16.11.102]) by beetle.greensocs.com (Postfix) with ESMTPS id B541E96F54; Thu, 23 Jan 2020 13:28:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=greensocs.com; s=mail; t=1579786120; 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=l7ju0ZKbntvlA8ZlehtqKUzVUtDM33mJD1fa7buuUqE=; b=xwkg3cyr2b1SqzsnOUrwV3+2N4tvKLx3qWLPHgsbDMktkDdrqRajxT7UYbV0CYOza4teJY PemuBJ5pWV99jW9MtnQcf/uDQnT+D6OMhS/ECKhZHvdliE+flAertaOK+eTXDZYZ0mvsL4 uyXvU6391/lIa06LLh4NIFOq0AY9uHE= From: Damien Hedde To: qemu-devel@nongnu.org Subject: [PATCH v8 06/11] hw/core/qdev: handle parent bus change regarding resettable Date: Thu, 23 Jan 2020 14:28:18 +0100 Message-Id: <20200123132823.1117486-7-damien.hedde@greensocs.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200123132823.1117486-1-damien.hedde@greensocs.com> References: <20200123132823.1117486-1-damien.hedde@greensocs.com> MIME-Version: 1.0 ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=greensocs.com; s=mail; t=1579786120; 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=l7ju0ZKbntvlA8ZlehtqKUzVUtDM33mJD1fa7buuUqE=; b=AZw+VsC/qE3JvEqAVqyTejatk5fLbIh7YFfzlCQbkmABUWAzQplt3AaqM4wQPWblCRbbLp R0Nn/3RRn9vmMwb+/YPkgTc/sOqixG/BxrFT/HN/JKtCPMSGWLtmzYiujCEakR6BwhwwYG s9EZmRzO5kpVvtuH9p6TOgPRoxqmpXk= ARC-Seal: i=1; s=mail; d=greensocs.com; t=1579786120; a=rsa-sha256; cv=none; b=iuCYPCyvEehZ6WJR/WOpa+EH6C1cEF+NZ/v60vkpNn+fXE0bLtn8C0QmLEpCdx+aDKU6cK qW3wcZSiDoRAsP4FRhuiZNzHKpozJ/xp/p+J0SWhaTBzJz18MmVEHtvJ7XOG35rpOSOl8x mvo3iSB4IESvEEs7CibDw6Pdz/6d66Y= ARC-Authentication-Results: i=1; beetle.greensocs.com; none X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 5.135.226.135 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Damien Hedde , peter.maydell@linaro.org, berrange@redhat.com, ehabkost@redhat.com, Richard Henderson , cohuck@redhat.com, mark.burton@greensocs.com, qemu-s390x@nongnu.org, edgari@xilinx.com, pbonzini@redhat.com, philmd@redhat.com, david@gibson.dropbear.id.au Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" In qdev_set_parent_bus(), when changing the parent bus of a realized device, if the source and destination buses are not in the same reset state, some adaptations are required. This patch adds needed call to resettable_change_parent() to make sure a device reset state stays coherent with its parent bus. The addition is a no-op if: 1. the device being parented is not realized. 2. the device is realized, but both buses are not under reset. Case 2 means that as long as qdev_set_parent_bus() is called during the machine realization procedure (which is before the machine reset so nothing is in reset), it is a no op. There are 52 call sites of qdev_set_parent_bus(). All but one fall into the no-op case: + 29 trivial calls related to virtio (in hw/{s390x,display,virtio}/ {vhost,virtio}-xxx.c) to set a vdev(or vgpu) composing device parent bus just before realizing the same vdev(vgpu). + hw/core/qdev.c: when creating a device in qdev_try_create() + hw/core/sysbus.c: when initializing a device in the sysbus + hw/i386/amd_iommu.c: before realizing AMDVIState/pci + hw/isa/piix4.c: before realizing PIIX4State/rtc + hw/misc/auxbus.c: when creating an AUXBus + hw/misc/auxbus.c: when creating an AUXBus child + hw/misc/macio/macio.c: when initializing a MACIOState child + hw/misc/macio/macio.c: before realizing NewWorldMacIOState/pmu + hw/misc/macio/macio.c: before realizing NewWorldMacIOState/cuda + hw/net/virtio-net.c: Used for migration when using the failover mechanism to migration a vfio-pci/net. It is a no-op because at this point the device is already on the bus. + hw/pci-host/designware.c: before realizing DesignwarePCIEHost/root + hw/pci-host/gpex.c: before realizing GPEXHost/root + hw/pci-host/prep.c: when initialiazing PREPPCIState/pci_dev + hw/pci-host/q35.c: before realizing Q35PCIHost/mch + hw/pci-host/versatile.c: when initializing PCIVPBState/pci_dev + hw/pci-host/xilinx-pcie.c: before realizing XilinxPCIEHost/root + hw/s390x/event-facility.c: when creating SCLPEventFacility/ TYPE_SCLP_QUIESCE + hw/s390x/event-facility.c: ditto with SCLPEventFacility/ TYPE_SCLP_CPU_HOTPLUG + hw/s390x/sclp.c: Not trivial because it is called on a SLCPDevice just after realizing it. Ok because at this point the destination bus (sysbus) is not in reset; the realize step is before the machine reset. + hw/sd/core.c: Not OK. Used in sdbus_reparent_card(). See below. + hw/ssi/ssi.c: Used to put spi slave on spi bus and connect the cs line in ssi_auto_connect_slave(). Ok because this function is only used in realize step in hw/ssi/aspeed_smc.ci, hw/ssi/imx_spi.c, hw/ssi/mss-spi.c, hw/ssi/xilinx_spi.c and hw/ssi/xilinx_spips.c. + hw/xen/xen-legacy-backend.c: when creating a XenLegacyDevice device + qdev-monitor.c: in device hotplug creation procedure before realize Note that this commit alone will have no effect, right now there is no use of resettable API to reset anything. So a bus will never be tagged as in-reset by this same API. The one place where side-effect will occurs is in hw/sd/core.c in sdbus_reparent_card(). This function is only used in the raspi machines, including during the sysbus reset procedure. This case will be carrefully handled when doing the multiple phase reset transition. Signed-off-by: Damien Hedde Reviewed-by: Peter Maydell Reviewed-by: Richard Henderson Tested-by: Philippe Mathieu-Daudé --- v6 update: there are now 3 more call sites (52 instead of 49). + hw/isa/piix4.c + hw/net/virtio-net.c + hw/virtio/vhost-user-fs-pci.c (in list below) Exhaustive list of the 29 "virtio" caller to qdev_set_parent_bus(): + hw/display/virtio-gpu-pci.c: VirtIOGPUPCIBase/vgpu realize + hw/display/virtio-vga.c: VirtIOVGABase/vgpu realize + hw/s390x/vhost-vsock-ccw.c: VHostVSockCCWState/vdev realize + hw/s390x/virtio-ccw-9p.c: V9fsCCWState/vdev realize + hw/s390x/virtio-ccw-balloon.c: VirtIOBalloonCcw/vdev realize + hw/s390x/virtio-ccw-blk.c: VirtIOBlkCcw/vdev realize + hw/s390x/virtio-ccw-crypto.c: VirtIOCryptoCcw/vdev realize + hw/s390x/virtio-ccw-gpu.c: VirtIOGPUCcw/vdev realize + hw/s390x/virtio-ccw-input.c: VirtIOInputCcw/vdev realize + hw/s390x/virtio-ccw-net.c: VirtIONetCcw/vdev realize + hw/s390x/virtio-ccw-rng.c: VirtIORNGCcw/vdev realize + hw/s390x/virtio-ccw-scsi.c: VirtIOSCSICcw/vdev realize + hw/s390x/virtio-ccw-scsi.c: VHostSCSICcw/vdev realize + hw/s390x/virtio-ccw-serial.c: VirtioSerialCcw/vdev realize + hw/virtio/vhost-scsi-pci.c: VHostSCSIPCI/vdev realize + hw/virtio/vhost-user-blk-pci.c: VHostUserBlkPCI/vdev realize + hw/virtio/vhost-user-fs-pci.c: VHostUserFSPCI/vdev realize + hw/virtio/vhost-user-scsi-pci.c: VHostUserSCSIPCI/vdev realize + hw/virtio/vhost-vsock-pci.c: VHostVSockPCI/vdev realize + hw/virtio/virtio-9p-pci.c: V9fsPCIState/vdev realize + hw/virtio/virtio-balloon-pci.c: VirtIOBalloonPCI/vdev realize + hw/virtio/virtio-blk-pci.c: VirtIOBlkPCI/vdev realize + hw/virtio/virtio-crypto-pci.c: VirtIOCryptoPCI/vdev realize + hw/virtio/virtio-input-pci.c: VirtIOInputPCI/vdev realize + hw/virtio/virtio-net-pci.c: VirtIONetPCI/vdev realize + hw/virtio/virtio-pmem-pci.c: VirtIOPMEMPCI/vdev realize + hw/virtio/virtio-rng-pci.c: VirtIORngPCI/vdev realize + hw/virtio/virtio-scsi-pci.c: VirtIOSCSIPCI/vdev realize + hw/virtio/virtio-serial-pci.c: VirtIOSerialPCI/vdev realize --- hw/core/qdev.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/hw/core/qdev.c b/hw/core/qdev.c index da47f30fd6..ce23b35383 100644 --- a/hw/core/qdev.c +++ b/hw/core/qdev.c @@ -96,25 +96,31 @@ static void bus_add_child(BusState *bus, DeviceState *child) void qdev_set_parent_bus(DeviceState *dev, BusState *bus) { - bool replugging = dev->parent_bus != NULL; + BusState *old_parent_bus = dev->parent_bus; - if (replugging) { + if (old_parent_bus) { trace_qdev_update_parent_bus(dev, object_get_typename(OBJECT(dev)), - dev->parent_bus, object_get_typename(OBJECT(dev->parent_bus)), + old_parent_bus, object_get_typename(OBJECT(old_parent_bus)), OBJECT(bus), object_get_typename(OBJECT(bus))); /* * Keep a reference to the device while it's not plugged into * any bus, to avoid it potentially evaporating when it is * dereffed in bus_remove_child(). + * Also keep the ref of the parent bus until the end, so that + * we can safely call resettable_change_parent() below. */ object_ref(OBJECT(dev)); bus_remove_child(dev->parent_bus, dev); - object_unref(OBJECT(dev->parent_bus)); } dev->parent_bus = bus; object_ref(OBJECT(bus)); bus_add_child(bus, dev); - if (replugging) { + if (dev->realized) { + resettable_change_parent(OBJECT(dev), OBJECT(bus), + OBJECT(old_parent_bus)); + } + if (old_parent_bus) { + object_unref(OBJECT(old_parent_bus)); object_unref(OBJECT(dev)); } }