| From 42f0ccca1a320e3d5869efc870c6c1670edcad82 Mon Sep 17 00:00:00 2001 |
| From: Henry Lin <henryl@nvidia.com> |
| Date: Wed, 13 Nov 2019 10:14:19 +0800 |
| Subject: [PATCH] ALSA: usb-audio: not submit urb for stopped endpoint |
| |
| commit 528699317dd6dc722dccc11b68800cf945109390 upstream. |
| |
| While output urb's snd_complete_urb() is executing, calling |
| prepare_outbound_urb() may cause endpoint stopped before |
| prepare_outbound_urb() returns and result in next urb submitted |
| to stopped endpoint. usb-audio driver cannot re-use it afterwards as |
| the urb is still hold by usb stack. |
| |
| This change checks EP_FLAG_RUNNING flag after prepare_outbound_urb() again |
| to let snd_complete_urb() know the endpoint already stopped and does not |
| submit next urb. Below kind of error will be fixed: |
| |
| [ 213.153103] usb 1-2: timeout: still 1 active urbs on EP #1 |
| [ 213.164121] usb 1-2: cannot submit urb 0, error -16: unknown error |
| |
| Signed-off-by: Henry Lin <henryl@nvidia.com> |
| Cc: <stable@vger.kernel.org> |
| Link: https://lore.kernel.org/r/20191113021420.13377-1-henryl@nvidia.com |
| Signed-off-by: Takashi Iwai <tiwai@suse.de> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c |
| index a2ab8e8d3a93..4a9a2f6ef5a4 100644 |
| --- a/sound/usb/endpoint.c |
| +++ b/sound/usb/endpoint.c |
| @@ -388,6 +388,9 @@ static void snd_complete_urb(struct urb *urb) |
| } |
| |
| prepare_outbound_urb(ep, ctx); |
| + /* can be stopped during prepare callback */ |
| + if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) |
| + goto exit_clear; |
| } else { |
| retire_inbound_urb(ep, ctx); |
| /* can be stopped during retire callback */ |
| -- |
| 2.7.4 |
| |
