From patchwork Mon Jun 5 08:57:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 13267101 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 636EBC77B73 for ; Mon, 5 Jun 2023 08:59:58 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q6621-0005ft-EL; Mon, 05 Jun 2023 04:57:41 -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 1q661s-0005cq-Ki for qemu-devel@nongnu.org; Mon, 05 Jun 2023 04:57:36 -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 1q661o-0004sZ-6z for qemu-devel@nongnu.org; Mon, 05 Jun 2023 04:57:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1685955447; 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=lRNJTSSNSAXDnrhqddr90/q7AO+amHqWivhyPshnE64=; b=KDcTuMSd4MaNHHMkdEMiQKNRY0N4FAAxZ3QT90EDTYfX9tr8gWqeJzh7bwCYRtPKWxS1gN Fqegv8dXkUg77p0irPUX2q8t9IszUXs+DawPM/5ni8p8pSOCYNfEL+NQWdEUulTbu3bNJl NrsQzxrt2irY4v/NW3IuS/ooihjQwak= 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-252-FvWKG5sgPbOqI08vXv5AKw-1; Mon, 05 Jun 2023 04:57:26 -0400 X-MC-Unique: FvWKG5sgPbOqI08vXv5AKw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id BAB368032EF; Mon, 5 Jun 2023 08:57:25 +0000 (UTC) Received: from merkur.fritz.box (unknown [10.39.193.25]) by smtp.corp.redhat.com (Postfix) with ESMTP id C240A40C6EC4; Mon, 5 Jun 2023 08:57:24 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, stefanha@redhat.com, hreitz@redhat.com, eblake@redhat.com, qemu-devel@nongnu.org Subject: [PATCH v2 08/11] block: Fix AioContext locking in bdrv_open_backing_file() Date: Mon, 5 Jun 2023 10:57:08 +0200 Message-Id: <20230605085711.21261-9-kwolf@redhat.com> In-Reply-To: <20230605085711.21261-1-kwolf@redhat.com> References: <20230605085711.21261-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Received-SPF: pass client-ip=170.10.133.124; envelope-from=kwolf@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, 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org bdrv_set_backing() requires the caller to hold the AioContext lock for @backing_hd. Take it in bdrv_open_backing_file() before calling the function. Signed-off-by: Kevin Wolf --- block.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/block.c b/block.c index 954b9923d9..d5f8231f31 100644 --- a/block.c +++ b/block.c @@ -3526,6 +3526,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, int ret = 0; bool implicit_backing = false; BlockDriverState *backing_hd; + AioContext *backing_hd_ctx; QDict *options; QDict *tmp_parent_options = NULL; Error *local_err = NULL; @@ -3610,8 +3611,12 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, /* Hook up the backing file link; drop our reference, bs owns the * backing_hd reference now */ + backing_hd_ctx = bdrv_get_aio_context(backing_hd); + aio_context_acquire(backing_hd_ctx); ret = bdrv_set_backing_hd(bs, backing_hd, errp); bdrv_unref(backing_hd); + aio_context_release(backing_hd_ctx); + if (ret < 0) { goto free_exit; }