This is a note to let you know that I've just added the patch titled
usb: xhci: Reset halted endpoint if trb is noop
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 810a624bd1b64b13ddcc2eb5c1880526a750a870 Mon Sep 17 00:00:00 2001
From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Date: Fri, 6 Oct 2017 17:45:29 +0300
Subject: usb: xhci: Reset halted endpoint if trb is noop
When a URB is cancled, xhci driver turns the untransferred trbs
into no-ops. If an endpoint stalls on a no-op trb that belongs
to the cancelled URB, the event handler won't reset the endpoint.
Hence, it will stay halted.
Link: http://marc.info/?l=linux-usb&m=149582598330127&w=2
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci-ring.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 48ae15afa59e..82c746e2d85c 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2580,15 +2580,21 @@ static int handle_tx_event(struct xhci_hcd *xhci,
(struct xhci_generic_trb *) ep_trb);
/*
- * No-op TRB should not trigger interrupts.
- * If ep_trb is a no-op TRB, it means the
- * corresponding TD has been cancelled. Just ignore
- * the TD.
+ * No-op TRB could trigger interrupts in a case where
+ * a URB was killed and a STALL_ERROR happens right
+ * after the endpoint ring stopped. Reset the halted
+ * endpoint. Otherwise, the endpoint remains stalled
+ * indefinitely.
*/
if (trb_is_noop(ep_trb)) {
- xhci_dbg(xhci,
- "ep_trb is a no-op TRB. Skip it for slot %u ep %u\n",
- slot_id, ep_index);
+ if (trb_comp_code == COMP_STALL_ERROR ||
+ xhci_requires_manual_halt_cleanup(xhci, ep_ctx,
+ trb_comp_code))
+ xhci_cleanup_halted_endpoint(xhci, slot_id,
+ ep_index,
+ ep_ring->stream_id,
+ td, ep_trb,
+ EP_HARD_RESET);
goto cleanup;
}
--
2.14.2