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=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 DC1F2C33CB1 for ; Tue, 14 Jan 2020 12:04:39 +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 A737724679 for ; Tue, 14 Jan 2020 12:04:39 +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="dSjbeN6i" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A737724679 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]:38130 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1irKw2-00015A-GP for qemu-devel@archiver.kernel.org; Tue, 14 Jan 2020 07:04:38 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:56418) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1irKaj-0008NE-8E for qemu-devel@nongnu.org; Tue, 14 Jan 2020 06:42:40 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1irKad-0003iK-Ut for qemu-devel@nongnu.org; Tue, 14 Jan 2020 06:42:36 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:44596 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1irKad-0003hv-Qt for qemu-devel@nongnu.org; Tue, 14 Jan 2020 06:42:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579002151; 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=sF9PT3VudShxE0wmWXTxFC1tzz8+9eCtUOBba9umQls=; b=dSjbeN6iHFJ54rYvZ8O2tBVVivVGcaesAKzEhZ5UIPHRfU+/p94V7GN+8knRK+kKzwtTpw CrOSDodQmt4RBeRlI8MMlTXMEKTrdAN1A/WGpaHPmkKYDDWG/9Dp9XdGyG1PwvONdj9IxD xG0fFO91ejyBWxuwq/qGxC76sDi8KJs= 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-241-MID95cAlNzCqRU41hmnghQ-1; Tue, 14 Jan 2020 06:42:30 -0500 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 A3EFA800A02; Tue, 14 Jan 2020 11:42:27 +0000 (UTC) Received: from secure.mitica (ovpn-116-207.ams2.redhat.com [10.36.116.207]) by smtp.corp.redhat.com (Postfix) with ESMTP id EDCD55DA70; Tue, 14 Jan 2020 11:42:22 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Subject: [PULL 24/30] migration/multifd: fix destroyed mutex access in terminating multifd threads Date: Tue, 14 Jan 2020 12:39:20 +0100 Message-Id: <20200114113926.3556-25-quintela@redhat.com> In-Reply-To: <20200114113926.3556-1-quintela@redhat.com> References: <20200114113926.3556-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-MC-Unique: MID95cAlNzCqRU41hmnghQ-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 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: Peter Maydell , Corey Minyard , Jason Wang , Jiahui Cen , Juan Quintela , "Michael S. Tsirkin" , Ying Fang , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , David Gibson , Laurent Vivier , Thomas Huth , Eduardo Habkost , Stefan Weil , "Dr. David Alan Gilbert" , qemu-arm@nongnu.org, Richard Henderson , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , qemu-ppc@nongnu.org, Paolo Bonzini , Stefan Berger Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Jiahui Cen One multifd will lock all the other multifds' IOChannel mutex to inform the= m to quit by setting p->quit or shutting down p->c. In this senario, if some multifds had already been terminated and multifd_load_cleanup/multifd_save_= cleanup had destroyed their mutex, it could cause destroyed mutex access when tryin= g lock their mutex. Here is the coredump stack: #0 0x00007f81a2794437 in raise () from /usr/lib64/libc.so.6 #1 0x00007f81a2795b28 in abort () from /usr/lib64/libc.so.6 #2 0x00007f81a278d1b6 in __assert_fail_base () from /usr/lib64/libc.so= .6 #3 0x00007f81a278d262 in __assert_fail () from /usr/lib64/libc.so.6 #4 0x000055eb1bfadbd3 in qemu_mutex_lock_impl (mutex=3D0x55eb1e2d1988,= file=3D, line=3D) at util/qemu-thread-posix.= c:64 #5 0x000055eb1bb4564a in multifd_send_terminate_threads (err=3D) at migration/ram.c:1015 #6 0x000055eb1bb4bb7f in multifd_send_thread (opaque=3D0x55eb1e2d19f8)= at migration/ram.c:1171 #7 0x000055eb1bfad628 in qemu_thread_start (args=3D0x55eb1e170450) at = util/qemu-thread-posix.c:502 #8 0x00007f81a2b36df5 in start_thread () from /usr/lib64/libpthread.so= .0 #9 0x00007f81a286048d in clone () from /usr/lib64/libc.so.6 To fix it up, let's destroy the mutex after all the other multifd threads h= ad been terminated. Signed-off-by: Jiahui Cen Signed-off-by: Ying Fang Reviewed-by: Juan Quintela Signed-off-by: Juan Quintela --- migration/ram.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/migration/ram.c b/migration/ram.c index 278b2ff87a..7221f54139 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1053,6 +1053,10 @@ void multifd_save_cleanup(void) if (p->running) { qemu_thread_join(&p->thread); } + } + for (i =3D 0; i < migrate_multifd_channels(); i++) { + MultiFDSendParams *p =3D &multifd_send_state->params[i]; + socket_send_channel_destroy(p->c); p->c =3D NULL; qemu_mutex_destroy(&p->mutex); @@ -1336,6 +1340,10 @@ int multifd_load_cleanup(Error **errp) qemu_sem_post(&p->sem_sync); qemu_thread_join(&p->thread); } + } + for (i =3D 0; i < migrate_multifd_channels(); i++) { + MultiFDRecvParams *p =3D &multifd_recv_state->params[i]; + object_unref(OBJECT(p->c)); p->c =3D NULL; qemu_mutex_destroy(&p->mutex); --=20 2.24.1