Patch "xhci: fix isoc endpoint dequeue from advancing too far on transaction error" has been added to the 3.14-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    xhci: fix isoc endpoint dequeue from advancing too far on transaction error

to the 3.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     xhci-fix-isoc-endpoint-dequeue-from-advancing-too-far-on-transaction-error.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From d104d0152a97fade389f47635b73a9ccc7295d0b Mon Sep 17 00:00:00 2001
From: Mathias Nyman <mathias.nyman@linux.intel.com>
Date: Thu, 30 Apr 2015 17:16:02 +0300
Subject: xhci: fix isoc endpoint dequeue from advancing too far on transaction error

From: Mathias Nyman <mathias.nyman@linux.intel.com>

commit d104d0152a97fade389f47635b73a9ccc7295d0b upstream.

Isoc TDs usually consist of one TRB, sometimes two. When all goes well we
receive only one success event for a TD, and move the dequeue pointer to
the next TD.

This fails if the TD consists of two TRBs and we get a transfer error
on the first TRB, we will then see two events for that TD.

Fix this by making sure the event we get is for the last TRB in that TD
before moving the dequeue pointer to the next TD. This will resolve some
of the uvc and dvb issues with the
"ERROR Transfer event TRB DMA ptr not part of current TD" error message

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/host/xhci-ring.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2213,8 +2213,13 @@ static int process_isoc_td(struct xhci_h
 		break;
 	case COMP_DEV_ERR:
 	case COMP_STALL:
+		frame->status = -EPROTO;
+		skip_td = true;
+		break;
 	case COMP_TX_ERR:
 		frame->status = -EPROTO;
+		if (event_trb != td->last_trb)
+			return 0;
 		skip_td = true;
 		break;
 	case COMP_STOP:


Patches currently in stable-queue which might be from mathias.nyman@linux.intel.com are

queue-3.14/xhci-fix-isoc-endpoint-dequeue-from-advancing-too-far-on-transaction-error.patch
queue-3.14/xhci-solve-full-event-ring-by-increasing-trbs_per_segment-to-256.patch
queue-3.14/xhci-gracefully-handle-xhci_irq-dead-device.patch