From patchwork Fri May 10 10:04:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Olaf Hering X-Patchwork-Id: 10938473 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6AC3E933 for ; Fri, 10 May 2019 10:06:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 521D228BB7 for ; Fri, 10 May 2019 10:06:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4482328BBB; Fri, 10 May 2019 10:06:31 +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=-5.0 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id A75DE28BB7 for ; Fri, 10 May 2019 10:06:29 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hP2OG-0003XA-AJ; Fri, 10 May 2019 10:04:32 +0000 Received: from us1-rack-dfw2.inumbo.com ([104.130.134.6]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hP2OE-0003X5-I4 for xen-devel@lists.xenproject.org; Fri, 10 May 2019 10:04:31 +0000 X-Inumbo-ID: feeb7b0c-730a-11e9-8980-bc764e045a96 Received: from mo6-p00-ob.smtp.rzone.de (unknown [2a01:238:20a:202:5300::8]) by us1-rack-dfw2.inumbo.com (Halon) with ESMTPS id feeb7b0c-730a-11e9-8980-bc764e045a96; Fri, 10 May 2019 10:04:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1557482667; s=strato-dkim-0002; d=aepfle.de; h=Message-Id:Date:Subject:Cc:To:From:X-RZG-CLASS-ID:X-RZG-AUTH:From: Subject:Sender; bh=i9W8uGZx09BS+hzNTWc1VaYZ22qQiDqiSj3YOyz8WG0=; b=ncVNZ7Ii9E1NrKbzcy+jBQkdeX0HdcKZxsvcOrEbwbOMZpIyP7qTutdHYhp/lEbxi8 D1cnsakiSgdHe7jR5/sM8fZ4vqYWlkh51xMwaqHk69u/BFL9RlMNe8RFZNz4GQPqKG0Y X0N/8+OKDH8+5owHFXM8gPH1He1xgXpNDQQJ+Nfh2weWUQZIOi4gO73BUPyhSzlA15oE iMkWjAYiqCpl08Okrl4x/Shci6LWrfgR2O5UV0I9dP255PP+/wEQmeie2oBvrSzxzQ6+ ONbENztaJPDcM5knyt6rX31zLdOPGKAE+FluPMzWqtEOAhbXjilFSCx5xMHXZk8S+NXm 2fzw== X-RZG-AUTH: ":P2EQZWCpfu+qG7CngxMFH1J+3q8wa/QXkBR9MXjAuzBW/OdlBZQ4AHSS3GlOjw==" X-RZG-CLASS-ID: mo00 Received: from sender by smtp.strato.de (RZmta 44.18 DYNA|AUTH) with ESMTPSA id 60a847v4AA4I0OU (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (curve secp521r1 with 521 ECDH bits, eq. 15360 bits RSA)) (Client did not present a certificate); Fri, 10 May 2019 12:04:18 +0200 (CEST) From: Olaf Hering To: xen-devel@lists.xenproject.org Date: Fri, 10 May 2019 12:04:16 +0200 Message-Id: <20190510100416.16658-1-olaf@aepfle.de> X-Mailer: git-send-email 2.16.4 MIME-Version: 1.0 Subject: [Xen-devel] [PATCH v3] libxl: fix migration of PV and PVH domUs with and without qemu X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Anthony PERARD , Wei Liu , Olaf Hering , Ian Jackson , =?utf-8?q?Roger_Pau_Monn=C3=A9?= Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP If a domU has a qemu-xen instance attached, it is required to call qemus "xen-save-devices-state" method. Without it, the receiving side of a PV or PVH migration may be unable to lock the image: xen be: qdisk-51712: xen be: qdisk-51712: error: Failed to get "write" lock error: Failed to get "write" lock xen be: qdisk-51712: xen be: qdisk-51712: initialise() failed initialise() failed To fix this bug, libxl__domain_suspend_device_model() and libxl__domain_resume_device_model() have to be called not only for HVM, but also if the active device_model is QEMU_XEN. Unfortunately, libxl__domain_build_info_setdefault() hardcodes b_info->device_model_version to QEMU_XEN if it does not know it any better. As a result libxl__device_model_version_running() will return incorrect values. This breaks domUs without a device_model. libxl__qmp_stop() would wait 10 seconds in qmp_open() for a qemu that will never appear. During this long timeframe the domU remains in state paused on the sending side. As a result network connections may be dropped. Once this bug is fixed as well, by just removing the assumption that every domU has a QEMU_XEN, there is no code to actually initialise b_info->device_model_version. There is a helper function libxl__need_xenpv_qemu(), which is used in various places to decide if a device_model has to be spawned. This function can not be used as is, just to fill device_model_version, because store_libxl_entry() was already called earlier. Create a new function to set device_model_version. Move existing code from libxl__domain_build_info_setdefault() to cover the HVM case. Add new code to cover non-HVM case, use libxl__need_xenpv_qemu() to set device_model_version. Update libxl__spawn_stub_dm() and initiate_domain_create() to call the new function prior libxl__domain_build_info_setdefault() because device_mode_version is expected to be initialzed. libxl_domain_need_memory() needs no update because it does not have a d_config available anyway, and the callers provide a populated b_info. Introduce LIBXL_DEVICE_MODEL_VERSION_NONE_REQUIRED for PV and PVH that have no need for a device_model to make the state explicit. v03: - rearrange code to make sure device_model_version is initialized before store_libxl_entry() is called v02: - update wording in a comment - remove stale goto in domcreate_launch_dm - initialize ret in libxl__need_xenpv_qemu Signed-off-by: Olaf Hering Cc: Roger Pau Monné Cc: Anthony PERARD --- v3 not runtime tested tools/libxl/libxl_create.c | 95 +++++++++++++++++++++++++++-------------- tools/libxl/libxl_dm.c | 2 + tools/libxl/libxl_dom_suspend.c | 8 +++- tools/libxl/libxl_internal.h | 2 + tools/libxl/libxl_types.idl | 1 + 5 files changed, 73 insertions(+), 35 deletions(-) diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c index 89fe80fc9c..73ee66a67e 100644 --- a/tools/libxl/libxl_create.c +++ b/tools/libxl/libxl_create.c @@ -27,6 +27,62 @@ #include +int libxl__domain_set_device_model(libxl__gc *gc, libxl_domain_config *d_config) +{ + libxl_domain_build_info *b_info = &d_config->b_info; + int ret; + + if (b_info->device_model_version) + return 0; + + switch (b_info->type) { + case LIBXL_DOMAIN_TYPE_HVM: + if (libxl_defbool_val(b_info->device_model_stubdomain)) { + b_info->device_model_version = + LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL; + } else { + b_info->device_model_version = libxl__default_device_model(gc); + } + break; + default: + ret = libxl__need_xenpv_qemu(gc, d_config); + switch (ret) { + case 1: + d_config->b_info.device_model_version = + LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN; + break; + case 0: + d_config->b_info.device_model_version = + LIBXL_DEVICE_MODEL_VERSION_NONE_REQUIRED; + break; + default: + LOGE(ERROR, "Unable to determine QEMU requisite"); + return ERROR_FAIL; + } + } + + if (b_info->device_model_version == LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN) { + const char *dm; + + dm = libxl__domain_device_model(gc, b_info); + ret = access(dm, X_OK); + if (ret < 0) { + /* qemu-xen unavailable, use qemu-xen-traditional */ + if (errno == ENOENT) { + LOGE(INFO, "qemu-xen is unavailable" + ", using qemu-xen-traditional instead"); + b_info->device_model_version = + LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL; + } else { + LOGE(ERROR, "qemu-xen access error"); + return ERROR_FAIL; + } + } + } + + return 0; +} + int libxl__domain_create_info_setdefault(libxl__gc *gc, libxl_domain_create_info *c_info) { @@ -86,39 +142,6 @@ int libxl__domain_build_info_setdefault(libxl__gc *gc, !b_info->device_model_ssidref) b_info->device_model_ssidref = SECINITSID_DOMDM; - if (!b_info->device_model_version) { - if (b_info->type == LIBXL_DOMAIN_TYPE_HVM) { - if (libxl_defbool_val(b_info->device_model_stubdomain)) { - b_info->device_model_version = - LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL; - } else { - b_info->device_model_version = libxl__default_device_model(gc); - } - } else { - b_info->device_model_version = - LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN; - } - if (b_info->device_model_version - == LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN) { - const char *dm; - - dm = libxl__domain_device_model(gc, b_info); - rc = access(dm, X_OK); - if (rc < 0) { - /* qemu-xen unavailable, use qemu-xen-traditional */ - if (errno == ENOENT) { - LOGE(INFO, "qemu-xen is unavailable" - ", using qemu-xen-traditional instead"); - b_info->device_model_version = - LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL; - } else { - LOGE(ERROR, "qemu-xen access error"); - return ERROR_FAIL; - } - } - } - } - if (b_info->blkdev_start == NULL) b_info->blkdev_start = libxl__strdup(NOGC, "xvda"); @@ -938,6 +961,12 @@ static void initiate_domain_create(libxl__egc *egc, goto error_out; } + ret = libxl__domain_set_device_model(gc, d_config); + if (ret) { + LOGD(ERROR, domid, "Unable to set domain device model"); + goto error_out; + } + ret = libxl__domain_create_info_setdefault(gc, &d_config->c_info); if (ret) { LOGD(ERROR, domid, "Unable to set domain create info defaults"); diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c index 2f19786bdd..086e566311 100644 --- a/tools/libxl/libxl_dm.c +++ b/tools/libxl/libxl_dm.c @@ -2168,6 +2168,8 @@ void libxl__spawn_stub_dm(libxl__egc *egc, libxl__stub_dm_spawn_state *sdss) dm_config->c_info.run_hotplug_scripts = guest_config->c_info.run_hotplug_scripts; + ret = libxl__domain_set_device_model(gc, dm_config); + if (ret) goto out; ret = libxl__domain_create_info_setdefault(gc, &dm_config->c_info); if (ret) goto out; ret = libxl__domain_build_info_setdefault(gc, &dm_config->b_info); diff --git a/tools/libxl/libxl_dom_suspend.c b/tools/libxl/libxl_dom_suspend.c index d1af3a6573..c492fe5dd1 100644 --- a/tools/libxl/libxl_dom_suspend.c +++ b/tools/libxl/libxl_dom_suspend.c @@ -379,7 +379,9 @@ static void domain_suspend_common_guest_suspended(libxl__egc *egc, libxl__ev_xswatch_deregister(gc, &dsps->guest_watch); libxl__ev_time_deregister(gc, &dsps->guest_timeout); - if (dsps->type == LIBXL_DOMAIN_TYPE_HVM) { + if (dsps->type == LIBXL_DOMAIN_TYPE_HVM || + libxl__device_model_version_running(gc, dsps->domid) == + LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN) { dsps->callback_device_model_done = domain_suspend_common_done; libxl__domain_suspend_device_model(egc, dsps); /* must be last */ return; @@ -459,7 +461,9 @@ int libxl__domain_resume(libxl__gc *gc, uint32_t domid, int suspend_cancel) goto out; } - if (type == LIBXL_DOMAIN_TYPE_HVM) { + if (type == LIBXL_DOMAIN_TYPE_HVM || + libxl__device_model_version_running(gc, domid) == + LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN) { rc = libxl__domain_resume_device_model(gc, domid); if (rc) { LOGD(ERROR, domid, "failed to resume device model:%d", rc); diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h index 44e0221284..25f113404b 100644 --- a/tools/libxl/libxl_internal.h +++ b/tools/libxl/libxl_internal.h @@ -1374,6 +1374,8 @@ _hidden int libxl__device_nextid(libxl__gc *gc, uint32_t domid, _hidden int libxl__resolve_domid(libxl__gc *gc, const char *name, uint32_t *domid); +_hidden int libxl__domain_set_device_model(libxl__gc *gc, + libxl_domain_config *d_config); /* * For each aggregate type which can be used as an input we provide: * diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl index cb4702fd7a..7d75bd3850 100644 --- a/tools/libxl/libxl_types.idl +++ b/tools/libxl/libxl_types.idl @@ -106,6 +106,7 @@ libxl_device_model_version = Enumeration("device_model_version", [ (0, "UNKNOWN"), (1, "QEMU_XEN_TRADITIONAL"), # Historical qemu-xen device model (qemu-dm) (2, "QEMU_XEN"), # Upstream based qemu-xen device model + (3, "NONE_REQUIRED"), ]) libxl_console_type = Enumeration("console_type", [