From patchwork Mon Jul 24 13:06:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juan Quintela X-Patchwork-Id: 1811801 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) 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: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=EjetHh7v; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4R8gSY6Dd6z1yYc for ; Mon, 24 Jul 2023 23:07:57 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qNvH7-00041V-5T; Mon, 24 Jul 2023 09:06:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qNvH3-00040g-93 for qemu-devel@nongnu.org; Mon, 24 Jul 2023 09:06:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qNvH1-0002XZ-D7 for qemu-devel@nongnu.org; Mon, 24 Jul 2023 09:06:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690204010; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jBYn87bb9I1f9KUD77mIUek71xIJdcNhfmFCCVLtKX8=; b=EjetHh7vWtcs1EqsVgmy6EBNzw9Qj9FlsMMTM6gdErLbzDWmKPN0/3sxQMxJ9P0BhBvJOI osVy/IFLQXHaQrTU55CaMh+RVP7ISLq0rpCpREivKgBaEA+8wOmV5Xd/dYpVGBg2wFLgaW NZd04aVjNXaOjZUPGaLsj5dwY0V4cQA= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-672-ibu4U3AuMka74eBeVjGXWA-1; Mon, 24 Jul 2023 09:06:49 -0400 X-MC-Unique: ibu4U3AuMka74eBeVjGXWA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id A5466830DC0; Mon, 24 Jul 2023 13:06:47 +0000 (UTC) Received: from secure.mitica (unknown [10.39.194.115]) by smtp.corp.redhat.com (Postfix) with ESMTP id B58F9F782D; Mon, 24 Jul 2023 13:06:45 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Cc: Laurent Vivier , Thomas Huth , Markus Armbruster , libvir-list@redhat.com, Paolo Bonzini , Peter Xu , Eric Blake , Juan Quintela , Leonardo Bras , Fabiano Rosas Subject: [PATCH 02/26] migration/multifd: Protect accesses to migration_threads Date: Mon, 24 Jul 2023 15:06:15 +0200 Message-Id: <20230724130639.93135-3-quintela@redhat.com> In-Reply-To: <20230724130639.93135-1-quintela@redhat.com> References: <20230724130639.93135-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=quintela@redhat.com; helo=us-smtp-delivery-124.mimecast.com 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Fabiano Rosas This doubly linked list is common for all the multifd and migration threads so we need to avoid concurrent access. Add a mutex to protect the data from concurrent access. This fixes a crash when removing two MigrationThread objects from the list at the same time during cleanup of multifd threads. Fixes: 671326201d ("migration: Introduce interface query-migrationthreads") Signed-off-by: Fabiano Rosas Reviewed-by: Peter Xu Reviewed-by: Juan Quintela Message-Id: <20230607161306.31425-3-farosas@suse.de> Signed-off-by: Juan Quintela --- migration/threadinfo.h | 2 -- migration/threadinfo.c | 15 ++++++++++++++- 2 files changed, 14 insertions(+), 3 deletions(-) diff --git a/migration/threadinfo.h b/migration/threadinfo.h index 8aa6999d58..2f356ff312 100644 --- a/migration/threadinfo.h +++ b/migration/threadinfo.h @@ -10,8 +10,6 @@ * See the COPYING file in the top-level directory. */ -#include "qemu/queue.h" -#include "qemu/osdep.h" #include "qapi/error.h" #include "qapi/qapi-commands-migration.h" diff --git a/migration/threadinfo.c b/migration/threadinfo.c index 3dd9b14ae6..262990dd75 100644 --- a/migration/threadinfo.c +++ b/migration/threadinfo.c @@ -10,23 +10,35 @@ * See the COPYING file in the top-level directory. */ +#include "qemu/osdep.h" +#include "qemu/queue.h" +#include "qemu/lockable.h" #include "threadinfo.h" +QemuMutex migration_threads_lock; static QLIST_HEAD(, MigrationThread) migration_threads; +static void __attribute__((constructor)) migration_threads_init(void) +{ + qemu_mutex_init(&migration_threads_lock); +} + MigrationThread *migration_threads_add(const char *name, int thread_id) { MigrationThread *thread = g_new0(MigrationThread, 1); thread->name = name; thread->thread_id = thread_id; - QLIST_INSERT_HEAD(&migration_threads, thread, node); + WITH_QEMU_LOCK_GUARD(&migration_threads_lock) { + QLIST_INSERT_HEAD(&migration_threads, thread, node); + } return thread; } void migration_threads_remove(MigrationThread *thread) { + QEMU_LOCK_GUARD(&migration_threads_lock); if (thread) { QLIST_REMOVE(thread, node); g_free(thread); @@ -39,6 +51,7 @@ MigrationThreadInfoList *qmp_query_migrationthreads(Error **errp) MigrationThreadInfoList **tail = &head; MigrationThread *thread = NULL; + QEMU_LOCK_GUARD(&migration_threads_lock); QLIST_FOREACH(thread, &migration_threads, node) { MigrationThreadInfo *info = g_new0(MigrationThreadInfo, 1); info->name = g_strdup(thread->name);