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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 3947AC0650E for ; Mon, 1 Jul 2019 08:52:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0FA6920B7C for ; Mon, 1 Jul 2019 08:52:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561971173; bh=3chGK0gprd1kh+pxU66lzTIhvo2YldKPF6w724fjlIY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=dPB2C1cocumKtkZf1EcHFQKK4NuwPYYwU9y069j5Bgbd+BhAvP54pn1B37fDrNshK vyYqyrY1GvROyBvDtQLwDXPiJM0FFoXa4itX8NAY6sWhYc4Akj0r2zGlaoabGALpr7 AXNliQyE6GlPxuDf4nJweF9FB3b1ZqooZl4x338I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728009AbfGAIww (ORCPT ); Mon, 1 Jul 2019 04:52:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:33430 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726442AbfGAIww (ORCPT ); Mon, 1 Jul 2019 04:52:52 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B81AA208C4; Mon, 1 Jul 2019 08:52:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561971171; bh=3chGK0gprd1kh+pxU66lzTIhvo2YldKPF6w724fjlIY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=K9HCOZBERRuq+R/68bB3W08jIh8ZYFcTOY9nXZBozKWQ77kLWh9n2jmHWNXH5rGDy WOnPxDmDLugNDjQY/f7PD/4BfoYVqyIl4pvkqFFfCVvJfmeLFg9iXJPM8+niVqz2Sh 1b/KzukH+sHFrmNBX2Re77oz2Cw+QOJBWu6w5iZk= Date: Mon, 1 Jul 2019 10:52:48 +0200 From: Greg KH To: JC Kuo Cc: linux-usb@vger.kernel.org, stern@rowland.harvard.edu, usb-storage@lists.one-eyed-alien.net, oneukum@suse.com Subject: Re: [PATCH] usb: storage: skip only when uas driver is loaded Message-ID: <20190701085248.GA28681@kroah.com> References: <20190701084848.32502-1-jckuo@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190701084848.32502-1-jckuo@nvidia.com> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Mon, Jul 01, 2019 at 04:48:48PM +0800, JC Kuo wrote: > When usb-storage driver detects a UAS capable device, it ignores the > device if CONFIG_USB_UAS is enabled. usb-storage driver assumes uas > driver certainly will be loaded. However, it's possible that uas > driver will not be loaded, for example, uas kernel module is not > installed properly or it is in modprobe blacklist. > > In case of uas driver not being loaded, the UAS capable device will > not fallback to work at Bulk-only-transfer mode. The device just > disappears without any notification to user/userspace. > > This commit changes usb-storage driver to skip UAS capable device > only when uas driver is already loaded to make sure the device will > at least work with Bulk protocol. But what happens if the driver is loaded afterward, because 'modprobe' was called by the driver core (or it should have been, because this is a device that supports that protocol)? I think you just broke working systems :( Why wouldn't the UAS driver get loaded automatically if it is configured in the system as it is today? thanks, greg k-h