From 1174d44906d517ddb4f98bbe58a44d4554d0ef90 Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Fri, 29 Jan 2021 15:00:40 +0200 Subject: [PATCH] xhci: handle stop endpoint command completion with endpoint in running state. Handle race where a stop endpoint command fails with "context state error" as hardware hasn't actually started the ring yet after a previous urb cancellation completed and restarted the endpoint. Flushing the doorbell write that restart the endpoint reduced these cases, but didn't completely resolve them. Check if the ring is running in the stop endpoint completion handler, and issue a new stop endpoint command in this case. Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20210129130044.206855-24-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-ring.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 3ba9158..307ccd4 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -983,6 +983,7 @@ static void xhci_handle_cmd_stop_ep(struct xhci_hcd *xhci, int slot_id, struct xhci_ep_ctx *ep_ctx; struct xhci_td *td = NULL; enum xhci_ep_reset_type reset_type; + struct xhci_command *command; if (unlikely(TRB_TO_SUSPEND_PORT(le32_to_cpu(trb->generic.field[3])))) { if (!xhci->devs[slot_id]) @@ -1030,6 +1031,18 @@ static void xhci_handle_cmd_stop_ep(struct xhci_hcd *xhci, int slot_id, xhci_handle_halted_endpoint(xhci, ep, 0, td, reset_type); xhci_stop_watchdog_timer_in_irq(xhci, ep); return; + case EP_STATE_RUNNING: + /* Race, HW handled stop ep cmd before ep was running */ + command = xhci_alloc_command(xhci, false, GFP_ATOMIC); + if (!command) + xhci_stop_watchdog_timer_in_irq(xhci, ep); + + mod_timer(&ep->stop_cmd_timer, + jiffies + XHCI_STOP_EP_CMD_TIMEOUT * HZ); + xhci_queue_stop_endpoint(xhci, command, slot_id, ep_index, 0); + xhci_ring_cmd_db(xhci); + + return; default: break; } -- 2.7.4