On 29.08.2012 15:29, Takashi Iwai wrote:
At Wed, 29 Aug 2012 13:26:25 +0200, Daniel Mack wrote:
[1 <text/plain; ISO-8859-1 (7bit)>] On 25.08.2012 14:17, Josh Boyer wrote:
On Sat, Aug 25, 2012 at 02:13:58PM +0200, Daniel Mack wrote:
On 25.08.2012 14:07, Bruno Wolff III wrote:
On Sat, Aug 25, 2012 at 14:02:51 +0200, Daniel Mack zonque@gmail.com wrote:
Can you revert commit e9ba389c5 ("ALSA: usb-audio: Fix scheduling-while-atomic bug in PCM capture stream") and see if that
I can try that, but it takes a long time to build a new kernel on my old hardware.
helps? If not, can you summarize again which kernels still work for you and which don't?
The latest kernel that works is 3.6.0-0.rc2.git1.2.fc18. The earliest that doesn't work is 3.6.0-0.rc2.git2.1.fc18.
The report you sent doesn't look like it could be caused by e9ba389c5. It fixes a kernel Ooops. But as it is the only relevant patch in that area, it would be interesting if reverting it fixes anything.
Yep, agreed. If this revert kernel doesn't work, we're likely down to a git bisect, Bruno.
Btw - thanks a lot for testing -rc kernels, much appreciated!
Indeed!
Could you please try this patch on top of Takashi's? Thanks again!
Daniel
[2 0001-ALSA-snd-usb-Fix-URB-cancellation-at-stream-start.patch <text/x-patch (7bit)>]
From 6617bb2463ae3fad21390b59cc2a71f96b9e9ca8 Mon Sep 17 00:00:00 2001
From: Daniel Mack zonque@gmail.com Date: Wed, 29 Aug 2012 13:17:05 +0200 Subject: [PATCH] ALSA: snd-usb: Fix URB cancellation at stream start
Commit e9ba389c5 ("ALSA: usb-audio: Fix scheduling-while-atomic bug in PCM capture stream") fixed a scheduling-while-atomic bug that happened when snd_usb_endpoint_start was called from the trigger callback, which is an atmic context. However, the patch breaks the idea of the endpoints reference counting, which is the reason why the driver has been refactored lately.
Revert that commit and let snd_usb_endpoint_start() take care of the URB cancellation again. As this function is called from both atomic and non-atomic context, add a flag to denote whether the function may sleep.
Signed-off-by: Daniel Mack zonque@gmail.com Cc: stable@kernel.org [3.5+]
sound/usb/endpoint.c | 10 ++++++++-- sound/usb/endpoint.h | 2 +- sound/usb/pcm.c | 13 +++++-------- 3 files changed, 14 insertions(+), 11 deletions(-)
diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c index c411812..678456c 100644 --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -799,7 +799,9 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep, /**
- snd_usb_endpoint_start: start an snd_usb_endpoint
- @ep: the endpoint to start
- @ep: the endpoint to start
- @can_sleep: flag indicating whether the operation is executed in
non-atomic context- A call to this function will increment the use count of the endpoint.
- In case it is not already running, the URBs for this endpoint will be
@@ -809,7 +811,7 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
- Returns an error if the URB submission failed, 0 in all other cases.
*/ -int snd_usb_endpoint_start(struct snd_usb_endpoint *ep) +int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep) { int err; unsigned int i; @@ -821,6 +823,10 @@ int snd_usb_endpoint_start(struct snd_usb_endpoint *ep) if (++ep->use_count != 1) return 0;
- /* just to be sure */
- deactivate_urbs(ep, 0, can_sleep);
- wait_clear_urbs(ep);
It'd be safer to protect the call of wait_clear_urbs() when can_sleep=0.
Right. New patch attached.