Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754848Ab3JUI4O (ORCPT ); Mon, 21 Oct 2013 04:56:14 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:39901 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754627Ab3JUIxb (ORCPT ); Mon, 21 Oct 2013 04:53:31 -0400 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, "Florian Wolter" , "Sarah Sharp" Date: Mon, 21 Oct 2013 09:46:28 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 143/149] xhci: Fix race between ep halt and URB cancellation In-Reply-To: X-SA-Exim-Connect-IP: 212.20.242.100 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 List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1576 Lines: 44 3.2.52-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Florian Wolter commit 526867c3ca0caa2e3e846cb993b0f961c33c2abb upstream. The halted state of a endpoint cannot be cleared over CLEAR_HALT from a user process, because the stopped_td variable was overwritten in the handle_stopped_endpoint() function. So the xhci_endpoint_reset() function will refuse the reset and communication with device can not run over this endpoint. https://bugzilla.kernel.org/show_bug.cgi?id=60699 Signed-off-by: Florian Wolter Signed-off-by: Sarah Sharp Signed-off-by: Ben Hutchings --- drivers/usb/host/xhci-ring.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -879,8 +879,12 @@ remove_finished_td: /* Otherwise ring the doorbell(s) to restart queued transfers */ ring_doorbell_for_active_rings(xhci, slot_id, ep_index); } - ep->stopped_td = NULL; - ep->stopped_trb = NULL; + + /* Clear stopped_td and stopped_trb if endpoint is not halted */ + if (!(ep->ep_state & EP_HALTED)) { + ep->stopped_td = NULL; + ep->stopped_trb = NULL; + } /* * Drop the lock and complete the URBs in the cancelled TD list. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/