From patchwork Tue Mar 13 23:14:54 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Igor Druzhinin X-Patchwork-Id: 10281279 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8C117601A0 for ; Tue, 13 Mar 2018 23:44:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7D1D0285CB for ; Tue, 13 Mar 2018 23:44:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 71B0D285CE; Tue, 13 Mar 2018 23:44:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id F0DC1285CB for ; Tue, 13 Mar 2018 23:44:27 +0000 (UTC) Received: from localhost ([::1]:43598 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1evtal-0003Tc-5N for patchwork-qemu-devel@patchwork.kernel.org; Tue, 13 Mar 2018 19:44:27 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36250) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1evt8K-0002wv-ED for qemu-devel@nongnu.org; Tue, 13 Mar 2018 19:15:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1evt8H-0000Kg-A6 for qemu-devel@nongnu.org; Tue, 13 Mar 2018 19:15:04 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:42852) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1evt8G-0000Ix-GJ for qemu-devel@nongnu.org; Tue, 13 Mar 2018 19:15:00 -0400 X-IronPort-AV: E=Sophos;i="5.47,466,1515456000"; d="scan'208";a="466632719" From: Igor Druzhinin To: , Date: Tue, 13 Mar 2018 23:14:54 +0000 Message-ID: <1520982894-4180-1-git-send-email-igor.druzhinin@citrix.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 66.165.176.63 Subject: [Qemu-devel] [PATCH v2] xen-pvdevice: Introduce a simplistic xen-pvdevice save state X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Igor Druzhinin , sstabellini@kernel.org, mst@redhat.com, paul.durrant@citrix.com, anthony.perard@citrix.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP This should help to avoid problems with accessing the device after migration/resume without PV drivers by migrating its PCI configuration space state. Without an explicitly defined state record it resets every time a VM migrates which confuses the OS and makes every access to xen-pvdevice MMIO region to fail. PV tools enable some logic to save and restore PCI configuration state from within the VM every time it migrates which basically hides the issue. Older systems will acquire the new record when migrated which should not change their state for worse. Signed-off-by: Igor Druzhinin Reviewed-by: Paul Durrant Acked-by: Anthony PERARD --- v2: add more concrete info --- hw/i386/xen/xen_pvdevice.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/hw/i386/xen/xen_pvdevice.c b/hw/i386/xen/xen_pvdevice.c index f748823..a146f18 100644 --- a/hw/i386/xen/xen_pvdevice.c +++ b/hw/i386/xen/xen_pvdevice.c @@ -71,6 +71,16 @@ static const MemoryRegionOps xen_pv_mmio_ops = { .endianness = DEVICE_LITTLE_ENDIAN, }; +static const VMStateDescription vmstate_xen_pvdevice = { + .name = "xen-pvdevice", + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_PCI_DEVICE(parent_obj, XenPVDevice), + VMSTATE_END_OF_LIST() + } +}; + static void xen_pv_realize(PCIDevice *pci_dev, Error **errp) { XenPVDevice *d = XEN_PV_DEVICE(pci_dev); @@ -120,6 +130,7 @@ static void xen_pv_class_init(ObjectClass *klass, void *data) k->class_id = PCI_CLASS_SYSTEM_OTHER; dc->desc = "Xen PV Device"; dc->props = xen_pv_props; + dc->vmsd = &vmstate_xen_pvdevice; } static const TypeInfo xen_pv_type_info = {