From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.codeaurora.org by pdx-caf-mail.web.codeaurora.org (Dovecot) with LMTP id rNWeLRlDGVvVBAAAmS7hNA ; Thu, 07 Jun 2018 14:38:17 +0000 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 8FCC26089E; Thu, 7 Jun 2018 14:38:17 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by smtp.codeaurora.org (Postfix) with ESMTP id EEBE6602FC; Thu, 7 Jun 2018 14:38:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org EEBE6602FC Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934199AbeFGOiB (ORCPT + 25 others); Thu, 7 Jun 2018 10:38:01 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:40462 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934178AbeFGOhz (ORCPT ); Thu, 7 Jun 2018 10:37:55 -0400 Received: from [148.252.241.226] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1fQvbo-0005Zv-Ng; Thu, 07 Jun 2018 15:09:48 +0100 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1fQvb2-0002sG-SY; Thu, 07 Jun 2018 15:09:00 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Greg Kroah-Hartman" , "Oliver Neukum" , "Hans de Goede" Date: Thu, 07 Jun 2018 15:05:21 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 136/410] usb: uas: unconditionally bring back host after reset In-Reply-To: X-SA-Exim-Connect-IP: 148.252.241.226 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.57-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Oliver Neukum commit cbeef22fd611c4f47c494b821b2b105b8af970bb upstream. Quoting Hans: If we return 1 from our post_reset handler, then our disconnect handler will be called immediately afterwards. Since pre_reset blocks all scsi requests our disconnect handler will then hang in the scsi_remove_host call. This is esp. bad because our disconnect handler hanging for ever also stops the USB subsys from enumerating any new USB devices, causes commands like lsusb to hang, etc. In practice this happens when unplugging some uas devices because the hub code may see the device as needing a warm-reset and calls usb_reset_device before seeing the disconnect. In this case uas_configure_endpoints fails with -ENODEV. We do not want to print an error for this, so this commit also silences the shost_printk for -ENODEV. ENDQUOTE However, if we do that we better drop any unconditional execution and report to the SCSI subsystem that we have undergone a reset but we are not operational now. Signed-off-by: Oliver Neukum Reported-by: Hans de Goede Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/usb/storage/uas.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) --- a/drivers/usb/storage/uas.c +++ b/drivers/usb/storage/uas.c @@ -1195,20 +1195,19 @@ static int uas_post_reset(struct usb_int return 0; err = uas_configure_endpoints(devinfo); - if (err) { + if (err && err != ENODEV) shost_printk(KERN_ERR, shost, "%s: alloc streams error %d after reset", __func__, err); - return 1; - } + /* we must unblock the host in every case lest we deadlock */ spin_lock_irqsave(shost->host_lock, flags); scsi_report_bus_reset(shost, 0); spin_unlock_irqrestore(shost->host_lock, flags); scsi_unblock_requests(shost); - return 0; + return err ? 1 : 0; } static int uas_suspend(struct usb_interface *intf, pm_message_t message)