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 9EE7BCAC5A7 for ; Mon, 22 Sep 2025 12:31:21 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1v0fg7-0006ew-UP; Mon, 22 Sep 2025 08:30:00 -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 1v0fg2-0006eA-Ku for qemu-devel@nongnu.org; Mon, 22 Sep 2025 08:29:54 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1v0ffo-0004GB-DX for qemu-devel@nongnu.org; Mon, 22 Sep 2025 08:29:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1758544176; 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=nHPzJPE4Aviny2rqeaKA0TEulZt6obVx0LxJ0NJJa7c=; b=clhbz5ZIgMmwJFgBl6rMhme+mIciKKRWOQSogNHzXKRurefOaSxAhoauxQeZizyJO6iks7 iFYB9zpUwZMZcW5wVsr68TnBCIBY4HXc+EYKe2jyn3Y781FjnN23N1rrxucS2pX6Y7obCN KkkJkjjdcwWjc2j6f++so8rkND2v3aA= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-25-9Pn8zsYDOXWroGC2HCh_hQ-1; Mon, 22 Sep 2025 08:29:35 -0400 X-MC-Unique: 9Pn8zsYDOXWroGC2HCh_hQ-1 X-Mimecast-MFC-AGG-ID: 9Pn8zsYDOXWroGC2HCh_hQ_1758544174 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E52D71800357; Mon, 22 Sep 2025 12:29:33 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.45.242.33]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 745F21800452; Mon, 22 Sep 2025 12:29:33 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 6798721E6A27; Mon, 22 Sep 2025 14:29:30 +0200 (CEST) From: Markus Armbruster To: Alex =?utf-8?Q?Benn=C3=A9e?= Cc: Daniel P. =?utf-8?Q?Berrang=C3=A9?= , Alessandro Ratti , alessandro.ratti@gmail.com, philmd@linaro.org, qemu-devel@nongnu.org Subject: Re: [PATCH v2] virtio: Add function name to error messages In-Reply-To: <87wm5qoig7.fsf@draig.linaro.org> ("Alex =?utf-8?Q?Benn=C3=A9?= =?utf-8?Q?e=22's?= message of "Mon, 22 Sep 2025 12:06:00 +0100") References: <87a52wqa03.fsf@draig.linaro.org> <20250915162643.44716-1-alessandro@0x65c.net> <20250915162643.44716-2-alessandro@0x65c.net> <87h5wulqm2.fsf@pond.sub.org> <87wm5qoig7.fsf@draig.linaro.org> Date: Mon, 22 Sep 2025 14:29:30 +0200 Message-ID: <877bxqk6vp.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.442, 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_PASS=-0.001, T_SPF_HELO_TEMPERROR=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 Alex Benn=C3=A9e writes: > Daniel P. Berrang=C3=A9 writes: > >> On Mon, Sep 22, 2025 at 12:37:57PM +0200, Markus Armbruster wrote: >>> Alessandro Ratti writes: >>>=20 >>> > Replace virtio_error() with a macro that automatically prepends the >>> > calling function name to error messages. This provides better context >>> > for debugging virtio issues by showing exactly which function >>> > encountered the error. >>> > >>> > Before: "Invalid queue size: 1024" >>> > After: "virtio_queue_set_num: Invalid queue size: 1024" >>> > >>> > The implementation uses a macro to insert __func__ at compile time, >>> > avoiding any runtime overhead while providing more specific error >>> > context than a generic "virtio:" prefix. >>>=20 >>> A need for function names and such in error messages suggests the error >>> messages are crap. >> >> I pretty much agree. If we take that view forwards, then I think our >> coding guidelines should explicitly state something like >> >> "Function names must never be included in error messages. >> >> The messages need to be sufficiently descriptive in their >> text, such that including function names is redundant" I'm in favor. > Ahh I missed the fact this ends up as an error_report. I think having > function names in debug output is fine. No argument! > It does however miss important information like which VirtIO device is > actually failing, despite having vdev passed down to the function. Yes, which device failed should definitely be reported. [...]