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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 3170AC3276C for ; Thu, 2 Jan 2020 22:40:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0650A21D7D for ; Thu, 2 Jan 2020 22:40:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578004832; bh=gBQc9wnm+0AAJoVibGTOaRCB9H6x608sIeSwwSe4xBQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=qw2pRLETO+gzUYEMHZfkSyAu+GNWyBTI5q6NqHCYF1FS2LaIFOnrp+jZ1FIjMIrbM ItWwxYCSkcr886/YlqREMt+pa2QNtSxP9dEkEC+Mde3k/KTSw9R4sGMu5rsHDF2bfN HaORFi3pc4XTMWarVLRD28EH1QG1sufaYxi5Mg48= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731059AbgABWiO (ORCPT ); Thu, 2 Jan 2020 17:38:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:51616 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731233AbgABWiH (ORCPT ); Thu, 2 Jan 2020 17:38:07 -0500 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 DB9A2222C3; Thu, 2 Jan 2020 22:38:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578004686; bh=gBQc9wnm+0AAJoVibGTOaRCB9H6x608sIeSwwSe4xBQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jSPeJnV2+AYOfVHcQI8c8PIG34Wr7vZZvwIyfmwZGTVp0gl1OyouvXC/7AmI0apts FlQkV99RiaJdYbO33WKrG1vgL/JCA1IYtYen+ioeD4FKh+U8qn0mDtYpT34LMyxabf AjfyYeB6rHBHgM86pLii7FxCR85JHzHGwSzK6vzY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Erkka Talvitie , Alan Stern Subject: [PATCH 4.4 083/137] USB: EHCI: Do not return -EPIPE when hub is disconnected Date: Thu, 2 Jan 2020 23:07:36 +0100 Message-Id: <20200102220557.857532955@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200102220546.618583146@linuxfoundation.org> References: <20200102220546.618583146@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Erkka Talvitie commit 64cc3f12d1c7dd054a215bc1ff9cc2abcfe35832 upstream. When disconnecting a USB hub that has some child device(s) connected to it (such as a USB mouse), then the stack tries to clear halt and reset device(s) which are _already_ physically disconnected. The issue has been reproduced with: CPU: IMX6D5EYM10AD or MCIMX6D5EYM10AE. SW: U-Boot 2019.07 and kernel 4.19.40. CPU: HP Proliant Microserver Gen8. SW: Linux version 4.2.3-300.fc23.x86_64 In this situation there will be error bit for MMF active yet the CERR equals EHCI_TUNE_CERR + halt. Existing implementation interprets this as a stall [1] (chapter 8.4.5). The possible conditions when the MMF will be active + halt can be found from [2] (Table 4-13). Fix for the issue is to check whether MMF is active and PID Code is IN before checking for the stall. If these conditions are true then it is not a stall. What happens after the fix is that when disconnecting a hub with attached device(s) the situation is not interpret as a stall. [1] [https://www.usb.org/document-library/usb-20-specification, usb_20.pdf] [2] [https://www.intel.com/content/dam/www/public/us/en/documents/ technical-specifications/ehci-specification-for-usb.pdf] Signed-off-by: Erkka Talvitie Reviewed-by: Alan Stern Cc: stable Link: https://lore.kernel.org/r/ef70941d5f349767f19c0ed26b0dd9eed8ad81bb.1576050523.git.erkka.talvitie@vincit.fi Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-q.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) --- a/drivers/usb/host/ehci-q.c +++ b/drivers/usb/host/ehci-q.c @@ -40,6 +40,10 @@ /*-------------------------------------------------------------------------*/ +/* PID Codes that are used here, from EHCI specification, Table 3-16. */ +#define PID_CODE_IN 1 +#define PID_CODE_SETUP 2 + /* fill a qtd, returning how much of the buffer we were able to queue up */ static int @@ -199,7 +203,7 @@ static int qtd_copy_status ( int status = -EINPROGRESS; /* count IN/OUT bytes, not SETUP (even short packets) */ - if (likely (QTD_PID (token) != 2)) + if (likely(QTD_PID(token) != PID_CODE_SETUP)) urb->actual_length += length - QTD_LENGTH (token); /* don't modify error codes */ @@ -215,6 +219,13 @@ static int qtd_copy_status ( if (token & QTD_STS_BABBLE) { /* FIXME "must" disable babbling device's port too */ status = -EOVERFLOW; + /* + * When MMF is active and PID Code is IN, queue is halted. + * EHCI Specification, Table 4-13. + */ + } else if ((token & QTD_STS_MMF) && + (QTD_PID(token) == PID_CODE_IN)) { + status = -EPROTO; /* CERR nonzero + halt --> stall */ } else if (QTD_CERR(token)) { status = -EPIPE;