From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752318AbdHJAfO (ORCPT ); Wed, 9 Aug 2017 20:35:14 -0400 Received: from mga07.intel.com ([134.134.136.100]:20973 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752174AbdHJAfN (ORCPT ); Wed, 9 Aug 2017 20:35:13 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.41,349,1498546800"; d="scan'208";a="135685175" Subject: Re: [PATCH v2 1/5] usb: xhci: Disable slot even virt-dev is null To: Mathias Nyman References: <1501122098-10935-1-git-send-email-baolu.lu@linux.intel.com> <1501122098-10935-2-git-send-email-baolu.lu@linux.intel.com> <598AC09D.4070003@linux.intel.com> Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, zhengjun.xing@linux.intel.com, Guoqing Zhang From: Lu Baolu Message-ID: <598BAA3F.7070103@linux.intel.com> Date: Thu, 10 Aug 2017 08:35:11 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <598AC09D.4070003@linux.intel.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 08/09/2017 03:58 PM, Mathias Nyman wrote: > On 27.07.2017 05:21, Lu Baolu wrote: >> xhci_disable_slot() is a helper for disabling a slot when a device >> goes away or recovers from error situations. Currently, it checks >> the corespoding virt-dev pointer and returns directly (w/o issuing >> disable slot command) if it's null. >> >> This is unnecessary and will cause problems in case where virt-dev >> allocation fails and xhci_disable_slot() is called to roll back the >> hardware state. Refer to the implementation of xhci_alloc_dev(). >> > > True, checking for xhci->devs[slot_id] doesn't work if xhci_alloc_dev() > failed xhci_alloc_virt_device() and calls xhci_disable_slot, > > but the virt dev check is needed for test mode, which will just try > to disable all slots from 1 to HCS_MAX_SLOTS: > > xhci_enter_test_mode(..) > /* Disable all Device Slots */ > for (i = 1; i <= HCS_MAX_SLOTS(xhci->hcs_params1); i++) { > retval = xhci_disable_slot(xhci, NULL, i); > > So, how about checking virt dev before this invoking? @@ -612,10 +612,12 @@ static int xhci_enter_test_mode(struct xhci_hcd *xhci, xhci_dbg(xhci, "Disable all slots\n"); spin_unlock_irqrestore(&xhci->lock, *flags); for (i = 1; i <= HCS_MAX_SLOTS(xhci->hcs_params1); i++) { - retval = xhci_disable_slot(xhci, NULL, i); - if (retval) - xhci_err(xhci, "Failed to disable slot %d, %d. Enter test mode anyway\n", - i, retval); + if (xhci->devs[i]) { + retval = xhci_disable_slot(xhci, NULL, i); + if (retval) + xhci_err(xhci, "Failed to disable slot %d, %d. Enter test mode anyway\n", + i, retval); + } } spin_lock_irqsave(&xhci->lock, *flags); /* Put all ports to the Disable state by clear PP */ Best regards, Lu Baolu > >> This patch removes lines to check virt-dev in xhci_disable_slot(). >> >> Fixes: f9e609b82479 ("usb: xhci: Add helper function xhci_disable_slot().") >> Cc: Guoqing Zhang >> Signed-off-by: Lu Baolu >> --- >> drivers/usb/host/xhci.c | 4 ---- >> 1 file changed, 4 deletions(-) >> >> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c >> index b2ff1ff..e69073f 100644 >> --- a/drivers/usb/host/xhci.c >> +++ b/drivers/usb/host/xhci.c >> @@ -3567,11 +3567,7 @@ int xhci_disable_slot(struct xhci_hcd *xhci, struct xhci_command *command, >> unsigned long flags; >> u32 state; >> int ret = 0; >> - struct xhci_virt_device *virt_dev; >> >> - virt_dev = xhci->devs[slot_id]; >> - if (!virt_dev) >> - return -EINVAL; >> if (!command) >> command = xhci_alloc_command(xhci, false, false, GFP_KERNEL); >> if (!command) >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >