From patchwork Thu Feb 14 04:33:22 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 1041810 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) 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=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 440Nwk48jFz9sNC for ; Thu, 14 Feb 2019 15:40:06 +1100 (AEDT) Received: from localhost ([127.0.0.1]:39900 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gu8oe-0001LG-Hm for incoming@patchwork.ozlabs.org; Wed, 13 Feb 2019 23:40:04 -0500 Received: from eggs.gnu.org ([209.51.188.92]:43471) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gu8iu-0005p8-FS for qemu-devel@nongnu.org; Wed, 13 Feb 2019 23:34:09 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gu8iq-0003bz-OS for qemu-devel@nongnu.org; Wed, 13 Feb 2019 23:34:06 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60828) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gu8il-00036b-3h; Wed, 13 Feb 2019 23:33:59 -0500 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 mx1.redhat.com (Postfix) with ESMTPS id CC1DD420A6; Thu, 14 Feb 2019 04:33:38 +0000 (UTC) Received: from localhost (unknown [10.64.242.17]) by smtp.corp.redhat.com (Postfix) with ESMTP id 71FFF600C0; Thu, 14 Feb 2019 04:33:33 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Date: Thu, 14 Feb 2019 12:33:22 +0800 Message-Id: <20190214043322.2354-2-stefanha@redhat.com> In-Reply-To: <20190214043322.2354-1-stefanha@redhat.com> References: <20190214043322.2354-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Thu, 14 Feb 2019 04:33:38 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 1/1] virtio-blk: set correct config size for the host driver 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: Kevin Wolf , Peter Maydell , qemu-block@nongnu.org, "Michael S. Tsirkin" , Max Reitz , Stefan Hajnoczi , Changpeng Liu Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Changpeng Liu Commit caa1ee43 "vhost-user-blk: add discard/write zeroes features support" added fields to struct virtio_blk_config. This changes the size of the config space and breaks migration from QEMU 3.1 and older: qemu-system-ppc64: get_pci_config_device: Bad config data: i=0x10 read: 41 device: 1 cmask: ff wmask: 80 w1cmask:0 qemu-system-ppc64: Failed to load PCIDevice:config qemu-system-ppc64: Failed to load virtio-blk:virtio qemu-system-ppc64: error while loading state for instance 0x0 of device 'pci@800000020000000:01.0/virtio-blk' qemu-system-ppc64: load of migration failed: Invalid argument Since virtio-blk doesn't support the "discard" and "write zeroes" features, it shouldn't even expose the associated fields in the config space actually. Just include all fields up to num_queues to match QEMU 3.1 and older. Signed-off-by: Changpeng Liu Reviewed-by: Michael S. Tsirkin Message-id: 1550022537-27565-1-git-send-email-changpeng.liu@intel.com Message-Id: <1550022537-27565-1-git-send-email-changpeng.liu@intel.com> Signed-off-by: Stefan Hajnoczi --- hw/block/virtio-blk.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 843bb2bec8..cf7f47eaba 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -28,6 +28,10 @@ #include "hw/virtio/virtio-bus.h" #include "hw/virtio/virtio-access.h" +/* We don't support discard yet, hide associated config fields. */ +#define VIRTIO_BLK_CFG_SIZE offsetof(struct virtio_blk_config, \ + max_discard_sectors) + static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq, VirtIOBlockReq *req) { @@ -757,7 +761,8 @@ static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config) blkcfg.alignment_offset = 0; blkcfg.wce = blk_enable_write_cache(s->blk); virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues); - memcpy(config, &blkcfg, sizeof(struct virtio_blk_config)); + memcpy(config, &blkcfg, VIRTIO_BLK_CFG_SIZE); + QEMU_BUILD_BUG_ON(VIRTIO_BLK_CFG_SIZE > sizeof(blkcfg)); } static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config) @@ -765,7 +770,8 @@ static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config) VirtIOBlock *s = VIRTIO_BLK(vdev); struct virtio_blk_config blkcfg; - memcpy(&blkcfg, config, sizeof(blkcfg)); + memcpy(&blkcfg, config, VIRTIO_BLK_CFG_SIZE); + QEMU_BUILD_BUG_ON(VIRTIO_BLK_CFG_SIZE > sizeof(blkcfg)); aio_context_acquire(blk_get_aio_context(s->blk)); blk_set_enable_write_cache(s->blk, blkcfg.wce != 0); @@ -948,8 +954,7 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) return; } - virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, - sizeof(struct virtio_blk_config)); + virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, VIRTIO_BLK_CFG_SIZE); s->blk = conf->conf.blk; s->rq = NULL;