From patchwork Mon Sep 11 09:46:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 13379098 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 40EF6EE7FF4 for ; Mon, 11 Sep 2023 09:51:09 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qfdVX-0005yz-Dx; Mon, 11 Sep 2023 05:47:03 -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 1qfdVW-0005yC-9P for qemu-devel@nongnu.org; Mon, 11 Sep 2023 05:47:02 -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 1qfdVU-0004k0-2h for qemu-devel@nongnu.org; Mon, 11 Sep 2023 05:47:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694425619; 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=zz9POUcr01LeTX9ECTiyphGQmAKIgG9oS3mtxlC07Uk=; b=eQaorf0Ewgyx492Yr5nu2DpHKWGYgiaVMMEXYSn9Pp0nO8XkeaIXqLOOU2SHYkYFOHyi++ pAhdyvpU0Na9ObxCcvjtuk8V7dUwgKIeJBqgfPaEHcEj34ueTJhlTR+XNVe0ka9cbKbG2O 9UKodMCLcXrrj8LbRaFui1yKvTb3PFg= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-100-77Z2wtSRM4uG9pAh6vaEzw-1; Mon, 11 Sep 2023 05:46:56 -0400 X-MC-Unique: 77Z2wtSRM4uG9pAh6vaEzw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 140163C19367; Mon, 11 Sep 2023 09:46:56 +0000 (UTC) Received: from merkur.redhat.com (unknown [10.39.192.243]) by smtp.corp.redhat.com (Postfix) with ESMTP id DAF2A40C6EBF; Mon, 11 Sep 2023 09:46:54 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, stefanha@redhat.com, eblake@redhat.com, eesposit@redhat.com, pbonzini@redhat.com, vsementsov@yandex-team.ru, qemu-devel@nongnu.org Subject: [PATCH v2 17/21] block: Take graph rdlock in bdrv_drop_intermediate() Date: Mon, 11 Sep 2023 11:46:16 +0200 Message-ID: <20230911094620.45040-18-kwolf@redhat.com> In-Reply-To: <20230911094620.45040-1-kwolf@redhat.com> References: <20230911094620.45040-1-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, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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 The function reads the parents list, so it needs to hold the graph lock. Signed-off-by: Kevin Wolf Reviewed-by: Emanuele Giuseppe Esposito Reviewed-by: Stefan Hajnoczi --- block.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/block.c b/block.c index 06d2a1b256..e024a6ccec 100644 --- a/block.c +++ b/block.c @@ -5938,9 +5938,11 @@ int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, backing_file_str = base->filename; } + bdrv_graph_rdlock_main_loop(); QLIST_FOREACH(c, &top->parents, next_parent) { updated_children = g_slist_prepend(updated_children, c); } + bdrv_graph_rdunlock_main_loop(); /* * It seems correct to pass detach_subchain=true here, but it triggers