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=-6.8 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 5CB0DC433E0 for ; Mon, 22 Jun 2020 09:50:44 +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 27A36206D7 for ; Mon, 22 Jun 2020 09:50:44 +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="NaquBRfe" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 27A36206D7 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]:42158 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jnJ6B-0007p2-BO for qemu-devel@archiver.kernel.org; Mon, 22 Jun 2020 05:50:43 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:54136) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jnIyX-00022p-SO for qemu-devel@nongnu.org; Mon, 22 Jun 2020 05:42:49 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:56934 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jnIyL-0003xN-KJ for qemu-devel@nongnu.org; Mon, 22 Jun 2020 05:42:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592818957; 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=PNSUg65sBMztUOY92rbEKRLBu711gTzd5r/0Dot1g54=; b=NaquBRfeA2yysdciK2MtL2m6x4kt5YQsAdQ/rUulzrzHi5hr1u8T3Nnx616ZjzLHoZsG3v t9q4pgnNl9xUbGiXbNlPhglbOm2LEgbkn/iwUeaJLTevRr8x/dVvy0VTV1MmwhbisMwbFK Snt3vqLe1IGvM1JB8OdDUeecCOTYRo8= 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-503-vRzIwnufPoGp5Pl1IH7JHw-1; Mon, 22 Jun 2020 05:42:35 -0400 X-MC-Unique: vRzIwnufPoGp5Pl1IH7JHw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5921C835B42; Mon, 22 Jun 2020 09:42:34 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-112-121.ams2.redhat.com [10.36.112.121]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3A33F10002BC; Mon, 22 Jun 2020 09:42:31 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 0A884113847A; Mon, 22 Jun 2020 11:42:28 +0200 (CEST) From: Markus Armbruster To: qemu-devel@nongnu.org Subject: [PATCH v2 12/16] qdev: Reject chardev property override Date: Mon, 22 Jun 2020 11:42:23 +0200 Message-Id: <20200622094227.1271650-13-armbru@redhat.com> In-Reply-To: <20200622094227.1271650-1-armbru@redhat.com> References: <20200622094227.1271650-1-armbru@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 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=207.211.31.120; envelope-from=armbru@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/22 02:57:26 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, 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=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN 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: kwolf@redhat.com, berrange@redhat.com, ehabkost@redhat.com, qemu-block@nongnu.org, mreitz@redhat.com, =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , pbonzini@redhat.com, jsnow@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" qdev_prop_set_chr() screws up when the property already has a non-null value: it neglects to release the old value. Both the old and the new backend become attached to the same device. Unlike for block devices (see previous commit), this can't be observed from the monitor (I think). Example: -serial null -chardev null,id=chr0 -global isa-serial.chardev=chr0 Special case: attempting to use the same backend both times crashes: $ qemu-system-x86_64 --nodefaults -serial null -global isa-serial.chardev=serial0 Unexpected error in qemu_chr_fe_init() at /work/armbru/qemu/chardev/char-fe.c:220: qemu-system-x86_64: Device 'serial0' is in use Aborted (core dumped) Yet another example: -device with multiple chardev=... (but not device_add, which silently drops all but the last duplicate property). Perhaps chardev property override could be made to work. Perhaps it should. I can't afford the time to figure this out now. What I can do reject usage that leaves backends in unhealthy states. For what it's worth, we've long done the same for netdev properties. Cc: Marc-André Lureau Cc: Paolo Bonzini Signed-off-by: Markus Armbruster --- hw/core/qdev-properties-system.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c index 6b5fc59901..2561fa09a8 100644 --- a/hw/core/qdev-properties-system.c +++ b/hw/core/qdev-properties-system.c @@ -244,6 +244,14 @@ static void set_chr(Object *obj, Visitor *v, const char *name, void *opaque, return; } + /* + * TODO Should this really be an error? If no, the old value + * needs to be released before we store the new one. + */ + if (!check_prop_still_unset(dev, name, be->chr, str, errp)) { + return; + } + if (!*str) { g_free(str); be->chr = NULL; -- 2.26.2