From patchwork Wed Sep 16 09:40:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oliver Neukum X-Patchwork-Id: 11779459 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 10371746 for ; Wed, 16 Sep 2020 09:40:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ED0AA2053B for ; Wed, 16 Sep 2020 09:40:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726697AbgIPJkq (ORCPT ); Wed, 16 Sep 2020 05:40:46 -0400 Received: from mx2.suse.de ([195.135.220.15]:48296 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726369AbgIPJkk (ORCPT ); Wed, 16 Sep 2020 05:40:40 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id E2405B203; Wed, 16 Sep 2020 09:40:54 +0000 (UTC) From: Oliver Neukum To: gregKH@linuxfoundation.org, linux-usb@vger.kernel.org Cc: Oliver Neukum Subject: [PATCH 1/2] UAS: fix disconnect by unplugging a hub Date: Wed, 16 Sep 2020 11:40:25 +0200 Message-Id: <20200916094026.30085-2-oneukum@suse.com> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20200916094026.30085-1-oneukum@suse.com> References: <20200916094026.30085-1-oneukum@suse.com> Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org The SCSI layer can go into an ugly loop if you ignore that a device is gone. You need to report an error in the command rather than in the return value of the queue method. We need to specifically check for ENODEV. The issue goes back to the introduction of the driver. v2: reorder patches Fixes: 115bb1ffa54c3 ("USB: Add UAS driver") Signed-off-by: Oliver Neukum --- drivers/usb/storage/uas.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c index d592071119ba..13696f03f800 100644 --- a/drivers/usb/storage/uas.c +++ b/drivers/usb/storage/uas.c @@ -662,8 +662,7 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd, if (devinfo->resetting) { cmnd->result = DID_ERROR << 16; cmnd->scsi_done(cmnd); - spin_unlock_irqrestore(&devinfo->lock, flags); - return 0; + goto zombie; } /* Find a free uas-tag */ @@ -699,6 +698,16 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd, cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB); err = uas_submit_urbs(cmnd, devinfo); + /* + * in case of fatal errors the SCSI layer is peculiar + * a command that has finished is a success for the purpose + * of queueing, no matter how fatal the error + */ + if (err == -ENODEV) { + cmnd->result = DID_ERROR << 16; + cmnd->scsi_done(cmnd); + goto zombie; + } if (err) { /* If we did nothing, give up now */ if (cmdinfo->state & SUBMIT_STATUS_URB) { @@ -709,6 +718,7 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd, } devinfo->cmnd[idx] = cmnd; +zombie: spin_unlock_irqrestore(&devinfo->lock, flags); return 0; }