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=-9.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 44767C55ABD for ; Thu, 12 Nov 2020 18:42:51 +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 A37BF22227 for ; Thu, 12 Nov 2020 18:42:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OLWHPQtb" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A37BF22227 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]:51746 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kdHYX-00079q-Ar for qemu-devel@archiver.kernel.org; Thu, 12 Nov 2020 13:42:49 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:48348) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kdHUI-0002ad-4c for qemu-devel@nongnu.org; Thu, 12 Nov 2020 13:38:26 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:30541) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kdHUG-0006S6-BO for qemu-devel@nongnu.org; Thu, 12 Nov 2020 13:38:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1605206303; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=J5Uru7LyvR0I1vk/rEPADBpvjbXgquFwOt7WjLL5UMg=; b=OLWHPQtb/R+RPIgX6wTTrr4o2Zadh9Cc+br9Wr0q5lGw+Wvk2NAqXwBMJBQggugkv/p9sB Cr8PKmjCPpgUgls+WTWp5xsGsDd1Yn+de/2txBAvWioUR1tWJLRASUxvanA6sV1RQHUd5x XM03WrrqRWARVqOmXJO5UJ477asX0x8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-180-nbJSEPFZPJqJJHV-UZkS8w-1; Thu, 12 Nov 2020 13:38:21 -0500 X-MC-Unique: nbJSEPFZPJqJJHV-UZkS8w-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6DC1618B9EC1; Thu, 12 Nov 2020 18:38:20 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-115-60.ams2.redhat.com [10.36.115.60]) by smtp.corp.redhat.com (Postfix) with ESMTP id C0CC85D9E4; Thu, 12 Nov 2020 18:38:15 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, kuhn.chenqun@huawei.com, zhengchuan@huawei.com, lihaotian9@huawei.com, longpeng2@huawei.com, liangpeng10@huawei.com, philmd@redhat.com, liuzhiqiang26@huawei.com Subject: [PULL 03/11] migration/multifd: fix hangup with TLS-Multifd due to blocking handshake Date: Thu, 12 Nov 2020 18:37:50 +0000 Message-Id: <20201112183758.203176-4-dgilbert@redhat.com> In-Reply-To: <20201112183758.203176-1-dgilbert@redhat.com> References: <20201112183758.203176-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/11/12 00:52:29 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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: stefanha@redhat.com, quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Chuan Zheng The qemu main loop could hang up forever when we enable TLS+Multifd. The Src multifd_send_0 invokes tls handshake, it sends hello to sever and wait response. However, the Dst main qemu loop has been waiting recvmsg() for multifd_recv_1. Both of Src and Dst main qemu loop are blocking and waiting for reponse which results in hanging up forever. Src: (multifd_send_0) Dst: (multifd_recv_1) multifd_channel_connect migration_channel_process_incoming multifd_tls_channel_connect migration_tls_channel_process_incoming multifd_tls_channel_connect qio_channel_tls_handshake_task qio_channel_tls_handshake gnutls_handshake qio_channel_tls_handshake_task ... qcrypto_tls_session_handshake ... gnutls_handshake ... ... ... recvmsg (Blocking I/O waiting for response) recvmsg (Blocking I/O waiting for response) Fix this by offloadinig handshake work to a background thread. Reported-by: Yan Jin Suggested-by: Daniel P. Berrangé Signed-off-by: Chuan Zheng Message-Id: <1604643893-8223-1-git-send-email-zhengchuan@huawei.com> Reviewed-by: Daniel P. Berrangé Signed-off-by: Dr. David Alan Gilbert --- migration/multifd.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) diff --git a/migration/multifd.c b/migration/multifd.c index 68b171fb61..88486b90d6 100644 --- a/migration/multifd.c +++ b/migration/multifd.c @@ -739,6 +739,19 @@ static void multifd_tls_outgoing_handshake(QIOTask *task, multifd_channel_connect(p, ioc, err); } +static void *multifd_tls_handshake_thread(void *opaque) +{ + MultiFDSendParams *p = opaque; + QIOChannelTLS *tioc = QIO_CHANNEL_TLS(p->c); + + qio_channel_tls_handshake(tioc, + multifd_tls_outgoing_handshake, + p, + NULL, + NULL); + return NULL; +} + static void multifd_tls_channel_connect(MultiFDSendParams *p, QIOChannel *ioc, Error **errp) @@ -754,12 +767,10 @@ static void multifd_tls_channel_connect(MultiFDSendParams *p, trace_multifd_tls_outgoing_handshake_start(ioc, tioc, hostname); qio_channel_set_name(QIO_CHANNEL(tioc), "multifd-tls-outgoing"); - qio_channel_tls_handshake(tioc, - multifd_tls_outgoing_handshake, - p, - NULL, - NULL); - + p->c = QIO_CHANNEL(tioc); + qemu_thread_create(&p->thread, "multifd-tls-handshake-worker", + multifd_tls_handshake_thread, p, + QEMU_THREAD_JOINABLE); } static bool multifd_channel_connect(MultiFDSendParams *p, -- 2.28.0