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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 4A07DC352AA for ; Wed, 2 Oct 2019 00:33:48 +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 1D39A20818 for ; Wed, 2 Oct 2019 00:33:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1D39A20818 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49762 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iFSaQ-0005zA-Db for qemu-devel@archiver.kernel.org; Tue, 01 Oct 2019 20:33:46 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39772) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iFRsB-0001Zm-HF for qemu-devel@nongnu.org; Tue, 01 Oct 2019 19:48:07 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iFRs9-00023w-9n for qemu-devel@nongnu.org; Tue, 01 Oct 2019 19:48:03 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:31202 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iFRs6-0001Rm-V8; Tue, 01 Oct 2019 19:48:00 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x91NlP46078942; Tue, 1 Oct 2019 19:47:34 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 2vcc4f00u2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 01 Oct 2019 19:47:34 -0400 Received: from m0098419.ppops.net (m0098419.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.27/8.16.0.27) with SMTP id x91NlXRH079208; Tue, 1 Oct 2019 19:47:34 -0400 Received: from ppma01dal.us.ibm.com (83.d6.3fa9.ip4.static.sl-reverse.com [169.63.214.131]) by mx0b-001b2d01.pphosted.com with ESMTP id 2vcc4f00tr-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 01 Oct 2019 19:47:33 -0400 Received: from pps.filterd (ppma01dal.us.ibm.com [127.0.0.1]) by ppma01dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id x91NjlYh029380; Tue, 1 Oct 2019 23:47:33 GMT Received: from b01cxnp22034.gho.pok.ibm.com (b01cxnp22034.gho.pok.ibm.com [9.57.198.24]) by ppma01dal.us.ibm.com with ESMTP id 2v9y59fahc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 01 Oct 2019 23:47:33 +0000 Received: from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com [9.57.199.106]) by b01cxnp22034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x91NlWUG49021242 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 1 Oct 2019 23:47:32 GMT Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 41CA32805A; Tue, 1 Oct 2019 23:47:32 +0000 (GMT) Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2602E28058; Tue, 1 Oct 2019 23:47:32 +0000 (GMT) Received: from localhost (unknown [9.53.179.213]) by b01ledav001.gho.pok.ibm.com (Postfix) with ESMTP; Tue, 1 Oct 2019 23:47:32 +0000 (GMT) From: Michael Roth To: qemu-devel@nongnu.org Subject: [PATCH 38/97] virtio-balloon: fix QEMU 4.0 config size migration incompatibility Date: Tue, 1 Oct 2019 18:45:17 -0500 Message-Id: <20191001234616.7825-39-mdroth@linux.vnet.ibm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191001234616.7825-1-mdroth@linux.vnet.ibm.com> References: <20191001234616.7825-1-mdroth@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-10-01_10:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=3 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910010203 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.158.5 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: qemu-stable@nongnu.org, Stefan Hajnoczi , "Michael S . Tsirkin" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Stefan Hajnoczi The virtio-balloon config size changed in QEMU 4.0 even for existing machine types. Migration from QEMU 3.1 to 4.0 can fail in some circumstances with the following error: qemu-system-x86_64: get_pci_config_device: Bad config data: i=0x10 read: a1 device: 1 cmask: ff wmask: c0 w1cmask:0 This happens because the virtio-balloon config size affects the VIRTIO Legacy I/O Memory PCI BAR size. Introduce a qdev property called "qemu-4-0-config-size" and enable it only for the QEMU 4.0 machine types. This way <4.0 machine types use the old size, 4.0 uses the larger size, and >4.0 machine types use the appropriate size depending on enabled virtio-balloon features. Live migration to and from old QEMUs to QEMU 4.1 works again as long as a versioned machine type is specified (do not use just "pc"!). Originally-by: Wolfgang Bumiller Signed-off-by: Stefan Hajnoczi Message-Id: <20190710141440.27635-1-stefanha@redhat.com> Reviewed-by: Dr. David Alan Gilbert Tested-by: Dr. David Alan Gilbert Tested-by: Wolfgang Bumiller Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin (cherry picked from commit 2bbadb08ce272d65e1f78621002008b07d1e0f03) Conflicts: hw/core/machine.c * drop context dep. on 0a71966253c Signed-off-by: Michael Roth --- hw/core/machine.c | 5 ++++- hw/virtio/virtio-balloon.c | 28 +++++++++++++++++++++++++--- include/hw/virtio/virtio-balloon.h | 2 ++ 3 files changed, 31 insertions(+), 4 deletions(-) diff --git a/hw/core/machine.c b/hw/core/machine.c index eb34f53a85..55b08f1466 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -24,7 +24,9 @@ #include "hw/pci/pci.h" #include "hw/mem/nvdimm.h" -GlobalProperty hw_compat_4_0[] = {}; +GlobalProperty hw_compat_4_0[] = { + { "virtio-balloon-device", "qemu-4-0-config-size", "true" }, +}; const size_t hw_compat_4_0_len = G_N_ELEMENTS(hw_compat_4_0); GlobalProperty hw_compat_3_1[] = { @@ -39,6 +41,7 @@ GlobalProperty hw_compat_3_1[] = { { "usb-tablet", "serial", "42" }, { "virtio-blk-device", "discard", "false" }, { "virtio-blk-device", "write-zeroes", "false" }, + { "virtio-balloon-device", "qemu-4-0-config-size", "false" }, }; const size_t hw_compat_3_1_len = G_N_ELEMENTS(hw_compat_3_1); diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index 2112874055..5579260fd4 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -615,6 +615,22 @@ virtio_balloon_free_page_report_notify(NotifierWithReturn *n, void *data) return 0; } +static size_t virtio_balloon_config_size(VirtIOBalloon *s) +{ + uint64_t features = s->host_features; + + if (s->qemu_4_0_config_size) { + return sizeof(struct virtio_balloon_config); + } + if (virtio_has_feature(features, VIRTIO_BALLOON_F_PAGE_POISON)) { + return sizeof(struct virtio_balloon_config); + } + if (virtio_has_feature(features, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { + return offsetof(struct virtio_balloon_config, poison_val); + } + return offsetof(struct virtio_balloon_config, free_page_report_cmd_id); +} + static void virtio_balloon_get_config(VirtIODevice *vdev, uint8_t *config_data) { VirtIOBalloon *dev = VIRTIO_BALLOON(vdev); @@ -635,7 +651,7 @@ static void virtio_balloon_get_config(VirtIODevice *vdev, uint8_t *config_data) } trace_virtio_balloon_get_config(config.num_pages, config.actual); - memcpy(config_data, &config, sizeof(struct virtio_balloon_config)); + memcpy(config_data, &config, virtio_balloon_config_size(dev)); } static int build_dimm_list(Object *obj, void *opaque) @@ -679,7 +695,7 @@ static void virtio_balloon_set_config(VirtIODevice *vdev, uint32_t oldactual = dev->actual; ram_addr_t vm_ram_size = get_current_ram_size(); - memcpy(&config, config_data, sizeof(struct virtio_balloon_config)); + memcpy(&config, config_data, virtio_balloon_config_size(dev)); dev->actual = le32_to_cpu(config.actual); if (dev->actual != oldactual) { qapi_event_send_balloon_change(vm_ram_size - @@ -766,7 +782,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) int ret; virtio_init(vdev, "virtio-balloon", VIRTIO_ID_BALLOON, - sizeof(struct virtio_balloon_config)); + virtio_balloon_config_size(s)); ret = qemu_add_balloon_handler(virtio_balloon_to_target, virtio_balloon_stat, s); @@ -897,6 +913,12 @@ static Property virtio_balloon_properties[] = { VIRTIO_BALLOON_F_DEFLATE_ON_OOM, false), DEFINE_PROP_BIT("free-page-hint", VirtIOBalloon, host_features, VIRTIO_BALLOON_F_FREE_PAGE_HINT, false), + /* QEMU 4.0 accidentally changed the config size even when free-page-hint + * is disabled, resulting in QEMU 3.1 migration incompatibility. This + * property retains this quirk for QEMU 4.1 machine types. + */ + DEFINE_PROP_BOOL("qemu-4-0-config-size", VirtIOBalloon, + qemu_4_0_config_size, false), DEFINE_PROP_LINK("iothread", VirtIOBalloon, iothread, TYPE_IOTHREAD, IOThread *), DEFINE_PROP_END_OF_LIST(), diff --git a/include/hw/virtio/virtio-balloon.h b/include/hw/virtio/virtio-balloon.h index 1afafb12f6..5a99293a45 100644 --- a/include/hw/virtio/virtio-balloon.h +++ b/include/hw/virtio/virtio-balloon.h @@ -71,6 +71,8 @@ typedef struct VirtIOBalloon { int64_t stats_poll_interval; uint32_t host_features; PartiallyBalloonedPage *pbp; + + bool qemu_4_0_config_size; } VirtIOBalloon; #endif -- 2.17.1