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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 BEBA6C433E0 for ; Thu, 14 May 2020 19:00:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0173206A5 for ; Thu, 14 May 2020 19:00:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728311AbgENTAS (ORCPT ); Thu, 14 May 2020 15:00:18 -0400 Received: from netrider.rowland.org ([192.131.102.5]:50677 "HELO netrider.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1729504AbgENSzu (ORCPT ); Thu, 14 May 2020 14:55:50 -0400 Received: (qmail 23212 invoked by uid 500); 14 May 2020 14:55:49 -0400 Date: Thu, 14 May 2020 14:55:49 -0400 From: Alan Stern To: Bin Liu , linux-usb@vger.kernel.org Subject: Re: [PATCH] usb: musb: return -ESHUTDOWN in urb when three-strikes error happened Message-ID: <20200514185549.GA22428@rowland.harvard.edu> References: <20200513213620.21541-1-b-liu@ti.com> <20200514013205.GA10515@rowland.harvard.edu> <20200514142803.GA11463@iaqt7> <20200514144053.GC12181@rowland.harvard.edu> <20200514150259.GB11463@iaqt7> <20200514153731.GC11463@iaqt7> <20200514162604.GA9571@rowland.harvard.edu> <20200514170023.GD11463@iaqt7> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200514170023.GD11463@iaqt7> Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Thu, May 14, 2020 at 12:00:23PM -0500, Bin Liu wrote: > > Still, it's worth pointing out that this change abuses the API (perhaps > > mentioning it in a comment). And it still would be preferable to fix > > Okay, I will add those notes in comment in v2. > > > the drivers in question, impractical though that may be. (I have a hard > > time believing there are really 500 of them getting this wrong...) > > I am not sure about it either, but yeah it is not practical to fix the > issue in device drivers. So far I have seen 3 reports of this issue: > > 1. with FTDI usb-serial adapter, the issue is in the usb serial generic > driver; It shouldn't be hard to fix this. We don't even need a delayed retry; the driver can simply treat -EPROTO as an unrecoverable error, just like -ESHUTDOWN. Alan Stern > 2. with a modem, the issue is in usb wwan driver as I fixed in the patch > I sent yesterday; > > 2. another modem, before I was able to locate the offending device > driver, the guy who reported the issue disappeared, and not responding > me. > > -Bin.