From patchwork Wed Mar 9 00:28:25 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 594672 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 5635C14090A; Wed, 9 Mar 2016 11:37:56 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1adS8Q-0001d6-8q; Wed, 09 Mar 2016 00:37:54 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1adS3L-0007E5-0v for kernel-team@lists.ubuntu.com; Wed, 09 Mar 2016 00:32:39 +0000 Received: from 1.general.kamal.us.vpn ([10.172.68.52] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1adS3K-0003FJ-J1; Wed, 09 Mar 2016 00:32:38 +0000 Received: from kamal by fourier with local (Exim 4.86) (envelope-from ) id 1adS3H-0007y4-Tz; Tue, 08 Mar 2016 16:32:35 -0800 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.19.y-ckt 047/196] Revert "xhci: don't finish a TD if we get a short-transfer event mid TD" Date: Tue, 8 Mar 2016 16:28:25 -0800 Message-Id: <1457483454-30115-48-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1457483454-30115-1-git-send-email-kamal@canonical.com> References: <1457483454-30115-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Cc: Greg Kroah-Hartman , Kamal Mostafa , Mathias Nyman X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.19.8-ckt16 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Mathias Nyman commit a6835090716a85f2297668ba593bd00e1051e662 upstream. This reverts commit e210c422b6fd ("xhci: don't finish a TD if we get a short transfer event mid TD") Turns out that most host controllers do not follow the xHCI specs and never send the second event for the last TRB in the TD if there was a short event mid-TD. Returning the URB directly after the first short-transfer event is far better than never returning the URB. (class drivers usually timeout after 30sec). For the hosts that do send the second event we will go back to treating it as misplaced event and print an error message for it. The origial patch was sent to stable kernels and needs to be reverted from there as well Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman Signed-off-by: Kamal Mostafa --- drivers/usb/host/xhci-ring.c | 10 ---------- 1 file changed, 10 deletions(-) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 565387c..fb9c10e 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2157,10 +2157,6 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td, EVENT_TRB_LEN(le32_to_cpu(event->transfer_len))); /* Fast path - was this the last TRB in the TD for this URB? */ if (event_trb == td->last_trb) { - if (td->urb_length_set && trb_comp_code == COMP_SHORT_TX) - return finish_td(xhci, td, event_trb, event, ep, - status, false); - if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) != 0) { td->urb->actual_length = td->urb->transfer_buffer_length - @@ -2212,12 +2208,6 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td, td->urb->actual_length += TRB_LEN(le32_to_cpu(cur_trb->generic.field[2])) - EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)); - - if (trb_comp_code == COMP_SHORT_TX) { - xhci_dbg(xhci, "mid bulk/intr SP, wait for last TRB event\n"); - td->urb_length_set = true; - return 0; - } } return finish_td(xhci, td, event_trb, event, ep, status, false);