From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=62.108.41.231 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792530752; b=ObO1gqY6+IlR/tgTBRtdd9J/hQAuWYRMJoXrDMszcgq53BYbshlFG0LDowugJeFuRrce fZXgIZTVlZR5gKSLBfyZNLxJPmAvrxFJG3cTPoFIgdCL6Qm5N0OF6jxCexaXrpI2LqAdy CnfAJcY6sx1d7THFcjzK3/4yuzTpjoqtYi+H6g8Vqq2Or3OEmyPLuDWaYiIYt8bqu4QsZ I+iTDtdNGFTf98xRbR27Lb8NpdY5dAjHS8DwF8i3VxY5tfarnvVd80dkC1EDqGoGD+k87 QdIXhmS/sEM0bOpTkmmgwWjZLZ8tS1/d2jipFwh86uZMu2tVAjZZauJahQd8+e79Icw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792530752; h=DMARC-Filter:Received:Received:Received:Received:Received: Received-SPF:MIME-Version:Date:From:To:Cc:Subject:In-Reply-To: References:Message-ID:X-Sender:Content-Type:Content-Transfer-Encoding: X-PPP-Message-ID:X-PPP-Vhost:X-POWERED-BY; bh=ziFQduvBFp2/a0Qma91+j1J9NIAtLrmEIaU+o8krKdU=; b=0UTldX/pvwXMovSosljOqaMzRHOyWy0qzfZSY0LN5Sf634QnCLStpLuq0y6PaFeygaYv tjWmkTIO65ehLMhmn+7Dwf36AKFn+lZpXEkJyoxp8Yj7n6eDZ2GG7XZuHYUQ6mvlvi46d VvQAFzhv595DrgbTmwdY7IrOoZrQLBGtaYVghKDX6VLiSpGirIHrxG1V8FTPchfZUSGri BWqXWwkT7ezt42y4rd6IcErhLnWf9J3d4a06BpVRFJdZpHcUlo6A0F6MkkhDiw4u9MUMH wsx00FI2V5bsICk8kOG00VBQ1hMNE2RSLLfKT8379mv/gYUBq8O3kskt2GjHFv9pdng== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none header.from=kiener-muenchen.de; spf=pass smtp.mailfrom=tldhost.de; arc=none smtp.remote-ip=62.108.41.231 Received: from mr02.mx01.tldhost.de (mr02.mx01.tldhost.de [62.108.41.231]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2F104606A31A for ; Tue, 20 Oct 2026 21:12:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 2F104606A31A Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kiener-muenchen.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=tldhost.de Received: from mx01.tldhost.de (localhost [127.0.0.1]) by mx01.tldhost.de (Postfix) with ESMTP id 5A386122E84; Tue, 20 Oct 2026 23:12:22 +0200 (CEST) Received: by mx01.tldhost.de (Postfix, from userid 1001) id 3DBA6122E77; Tue, 20 Oct 2026 23:12:22 +0200 (CEST) Received: from mailout.tldhost.de (mailout.tldhost.de [84.19.26.10]) by mx01.tldhost.de (Postfix) with ESMTPS id 2BB90122E70; Tue, 20 Oct 2026 23:12:20 +0200 (CEST) Received: from mailout.tldhost.de (localhost.localdomain [127.0.0.1]) by mailout.tldhost.de (Proxmox) with ESMTP id 0ED5F82A0A; Tue, 20 Oct 2026 23:12:20 +0200 (CEST) Received: from server12.tldhost.de (server12.tldhost.de [84.19.26.112]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519) (No client certificate requested) by mailout.tldhost.de (Proxmox) with ESMTPS; Tue, 20 Oct 2026 23:12:19 +0200 (CEST) Authentication-Results: server12.tldhost.de; spf=pass (sender IP is ::1) smtp.mailfrom=guido@kiener-muenchen.de smtp.helo=webmail.kiener-muenchen.de Received-SPF: pass (server12.tldhost.de: connection is authenticated) X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Date: Tue, 20 Oct 2026 23:12:18 +0200 From: guido@kiener-muenchen.de To: Nicolai Buchwitz Cc: Michal Pecio , Greg Kroah-Hartman , Steve Bayless , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH 0/4] usb: usbtmc: fix undersized high-speed bulk packets on xHCI In-Reply-To: References: <20261020-fix-usbtmc-short-packets-v1-0-903f4d029193@tipi-net.de> <20261020184244.69b78d5e.michal.pecio@gmail.com> Message-ID: X-Sender: guido@kiener-muenchen.de Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-PPP-Message-ID: <179253073937.20268.16253300091701606469@server12.tldhost.de> X-PPP-Vhost: kiener-muenchen.de X-POWERED-BY: TLDHost.de - AV:CLEAN SPAM:OK Hi Nicolai, The USBTMC protocol was defined by the IVI Foundation. The purpose of a specification is to ensure that manufacturers adhere to the agreed rules so that maximum compatibility between T&M instruments and client software (e.g. NI‑VISA, Keysight VISA, R&S VISA, etc.) is guaranteed. The Linux USBTMC kernel driver is a class driver that has been tested by members of the IVI Foundation and ensures reliable communication with their devices. Therefore every manufacturer of USBTMC devices should comply with the specification and cannot expect bugs in device firmware to be fixed by patches to the USBTMC driver on Windows, Linux, or macOS. If such an approach were tolerated, the development costs that one manufacturer omitted would be shifted onto and multiplied across all other manufacturers. If there is a demonstrable bug in the USBTMC kernel driver, we can certainly discuss fixing the driver. Otherwise I cannot support adding device‑specific patches to a class driver. Over time that would increase the driver’s complexity and encourage other manufacturers not to follow the jointly developed specification — something that would certainly not be acceptable for the TCP/IP stack either. Best regards, Guido Kiener