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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 A849CC4360C for ; Fri, 4 Oct 2019 11:24:36 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 7CBC22070B for ; Fri, 4 Oct 2019 11:24:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7CBC22070B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:46606 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iGLhC-0001bK-EG for qemu-devel@archiver.kernel.org; Fri, 04 Oct 2019 07:24:26 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34914) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iGKhp-0008WQ-Uu for qemu-devel@nongnu.org; Fri, 04 Oct 2019 06:21:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iGKho-0002lp-HM for qemu-devel@nongnu.org; Fri, 04 Oct 2019 06:21:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59793) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iGKho-0002l5-9S for qemu-devel@nongnu.org; Fri, 04 Oct 2019 06:21:00 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 867EB3090FDE for ; Fri, 4 Oct 2019 10:20:58 +0000 (UTC) Received: from localhost (ovpn-112-73.ams2.redhat.com [10.36.112.73]) by smtp.corp.redhat.com (Postfix) with ESMTP id 81B5960BE1; Fri, 4 Oct 2019 10:20:53 +0000 (UTC) From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= To: qemu-devel@nongnu.org Subject: [PATCH v5 0/8] Add dbus-vmstate Date: Fri, 4 Oct 2019 14:20:43 +0400 Message-Id: <20191004102051.19738-1-marcandre.lureau@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.43]); Fri, 04 Oct 2019 10:20:58 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 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: berrange@redhat.com, quintela@redhat.com, mprivozn@redhat.com, dgilbert@redhat.com, =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hi, With external processes or helpers participating to the VM support, it becomes necessary to handle their migration. Various options exist to transfer their state: 1) as the VM memory, RAM or devices (we could say that's how vhost-user devices can be handled today, they are expected to restore from ring state) 2) other "vmstate" (as with TPM emulator state blobs) 3) left to be handled by management layer 1) is not practical, since an external processes may legitimatelly need arbitrary state date to back a device or a service, or may not even have an associated device. 2) needs ad-hoc code for each helper, but is simple and working 3) is complicated for management layer, QEMU has the migration timing The proposed "dbus-vmstate" object will connect to a given D-Bus address, and save/load from org.qemu.VMState1 owners on migration. Thus helpers can easily have their state migrated with QEMU, without implementing ad-hoc support (such as done for TPM emulation) D-Bus is ubiquitous on Linux (it is systemd IPC), and can be made to work on various other OSes. There are several implementations and good bindings for various languages. (the tests/dbus-vmstate-test.c is a good example of how simple the implementation of services can be, even in C) dbus-vmstate is put into use by the libvirt series "[PATCH 00/23] Use a slirp helper process". v5: - trying to fix patchew/ci: install dbus-daemon in containers, skip test if unavailable v4: - add Daniel security scenarios to the D-Bus document - misc doc improvements - add "util: add dbus helper unit" patch, with qemu_dbus_get_queued_owners() - add "configure: add GDBUS_CODEGEN", explaining why gio-unix is required when available - silence the expected failing tests - update copyright headers, MAINTAINERS - add r-b/a-b tags - rebased (Note: patchew dbus test fails for unclear reasons, but I can't reproduce locally nor on travis) v3: - after various discussions on helper processes, we settled on a preference for having a bus for communications. This version is actually v1 updated. - added a dbus.rst document to describe D-Bus recommendations for QEMU - added dbus-vmstate-daemon.sh to play with the dbus-daemon configuration (although it is not very useful in the context of a single UID) - added a new vmstate interface, so that any object can implement VMStateDescription, and converted dbus-vmstate - added "migration: fix vmdesc leak on vmstate_save() error" - convert to g_auto v2: - D-Bus is most common and practical through a bus, but it requires a daemon to be running. I argue that the benefits outweight the cost of running an extra daemon in v1 in the context of multi-process qemu, but it is also possible to connect in p2p mode as done in this new version. Marc-Andr=C3=A9 Lureau (8): vmstate: add qom interface to get id vmstate: replace DeviceState with VMStateIf docs: start a document to describe D-Bus usage util: add dbus helper unit Add dbus-vmstate object configure: add GDBUS_CODEGEN dockerfiles: add dbus-daemon to some of latest distributions tests: add dbus-vmstate-test MAINTAINERS | 12 + backends/Makefile.objs | 4 + backends/dbus-vmstate.c | 496 +++++++++++++++++++++++ configure | 7 + docs/interop/dbus-vmstate.rst | 74 ++++ docs/interop/dbus.rst | 104 +++++ docs/interop/index.rst | 2 + hw/block/onenand.c | 2 +- hw/core/Makefile.objs | 1 + hw/core/qdev.c | 21 +- hw/core/vmstate-if.c | 23 ++ hw/ide/cmd646.c | 2 +- hw/ide/isa.c | 2 +- hw/ide/piix.c | 2 +- hw/ide/via.c | 2 +- hw/misc/max111x.c | 2 +- hw/net/eepro100.c | 4 +- hw/nvram/eeprom93xx.c | 4 +- hw/ppc/spapr_drc.c | 9 +- hw/ppc/spapr_iommu.c | 4 +- hw/s390x/s390-skeys.c | 2 +- include/hw/vmstate-if.h | 40 ++ include/migration/register.h | 4 +- include/migration/vmstate.h | 10 +- include/qemu/dbus.h | 18 + migration/savevm.c | 20 +- stubs/vmstate.c | 4 +- tests/Makefile.include | 23 +- tests/dbus-vmstate-daemon.sh | 95 +++++ tests/dbus-vmstate-test.c | 399 ++++++++++++++++++ tests/dbus-vmstate1.xml | 12 + tests/docker/dockerfiles/centos7.docker | 1 + tests/docker/dockerfiles/debian10.docker | 1 + tests/docker/dockerfiles/fedora.docker | 1 + tests/docker/dockerfiles/ubuntu.docker | 1 + util/Makefile.objs | 3 + util/dbus.c | 55 +++ 37 files changed, 1428 insertions(+), 38 deletions(-) create mode 100644 backends/dbus-vmstate.c create mode 100644 docs/interop/dbus-vmstate.rst create mode 100644 docs/interop/dbus.rst create mode 100644 hw/core/vmstate-if.c create mode 100644 include/hw/vmstate-if.h create mode 100644 include/qemu/dbus.h create mode 100755 tests/dbus-vmstate-daemon.sh create mode 100644 tests/dbus-vmstate-test.c create mode 100644 tests/dbus-vmstate1.xml create mode 100644 util/dbus.c --=20 2.23.0