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 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 A364DC02180 for ; Wed, 15 Jan 2025 14:36:29 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tY4VF-0001dN-Qb; Wed, 15 Jan 2025 09:36:17 -0500 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 1tY4VA-0001bU-KI; Wed, 15 Jan 2025 09:36:14 -0500 Received: from mail.xenproject.org ([104.130.215.37]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tY4V8-0006do-O3; Wed, 15 Jan 2025 09:36:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xenproject.org; s=20200302mail; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date; bh=BzHVI2QHsblFL3UdSqVJ+hb2V1l2T08WDs3ev7B3rhU=; b=xX5GMUOF7fb6dPESjNoX3BU1Pt xYQSp1DvKS8gZEuQnyeqmVK43oN0bHMO89pCSUnersCo3ye9upzNNr0g7dwu0UGn6aXcbOJo54QgE DAIyQtU2LBsbuxLKVdygZtPrXLA8xez8lKro5Q/a6/+TMqipsB3nGXAKKT2wZU0mOA4s=; Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.96) (envelope-from ) id 1tY4V0-0061ge-2w; Wed, 15 Jan 2025 14:36:03 +0000 Received: from [2a01:e0a:1da:8420:b77:bd5:6e45:7633] (helo=l14) by xenbits.xenproject.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1tY4V0-006U5Y-2l; Wed, 15 Jan 2025 14:36:03 +0000 Date: Wed, 15 Jan 2025 15:36:00 +0100 From: Anthony PERARD To: Roger Pau Monne Cc: qemu-devel@nongnu.org, Stefano Stabellini , Paul Durrant , "Edgar E. Iglesias" , Kevin Wolf , Hanna Reitz , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , Paolo Bonzini , xen-devel@lists.xenproject.org, qemu-block@nongnu.org Subject: Re: [PATCH v2 2/2] xen: do not use '%ms' scanf specifier Message-ID: References: <20250110093531.23221-1-roger.pau@citrix.com> <20250110093531.23221-3-roger.pau@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250110093531.23221-3-roger.pau@citrix.com> Received-SPF: pass client-ip=104.130.215.37; envelope-from=anthony@xenproject.org; helo=mail.xenproject.org X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 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 On Fri, Jan 10, 2025 at 10:35:31AM +0100, Roger Pau Monne wrote: > diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c > index ef0c2912efa1..989e75fef88f 100644 > --- a/hw/char/xen_console.c > +++ b/hw/char/xen_console.c > @@ -550,7 +550,8 @@ static void xen_console_device_create(XenBackendInstance *backend, > goto fail; > } > > - if (xs_node_scanf(xsh, XBT_NULL, fe, "type", errp, "%ms", &type) != 1) { > + type = xs_node_read(xsh, XBT_NULL, NULL, errp, "%s/%s", fe, "type"); > + if (!type) { > error_prepend(errp, "failed to read console device type: "); > goto fail; > } > @@ -568,7 +569,8 @@ static void xen_console_device_create(XenBackendInstance *backend, > > snprintf(label, sizeof(label), "xencons%ld", number); > > - if (xs_node_scanf(xsh, XBT_NULL, fe, "output", NULL, "%ms", &output) == 1) { > + output = xs_node_read(xsh, XBT_NULL, NULL, errp, "%s/%s", fe, "output"); This now set `errp` on error, when `output == NULL`. In case `output` is NULL, we check for `number` instead and may generate an error message that probably doesn't really make sense. "console: No serial device #2 found: failed to read from /frontend_path/output" And if number == 0, we tried to create a null device, and if that failed, the error message will just be about the missing xenstore path as error_setg() will not set `errp` again. Could you keep ignoring errors from xs_node_read() like it was done with xs_node_scanf() (I mean pass `NULL` instead of `errp`)? And we will need another patch to fix the wrong use of `error_prepend()` and use `error_setg` instead when `serial_hd()` fails. > + if (output) { > /* > * FIXME: sure we want to support implicit > * muxed monitors here? Thanks, -- Anthony PERARD