On Tue, Jan 22, 2013 at 05:43:40PM +0100, Takashi Iwai wrote:
> [NOTE: the regression below is found only in 3.2-3.4 stable trees, so
> there is no upstream commit corresponding to this patch]
>
> The recent fix for the race at disconnection of usb-audio devices
> (upstream commit 978520b7) triggers Oops when a device is unplugged
> while playing on 3.2 and 3.4 kernels. The culprit is that the
> shutdown flag check was wrongly added around the urb deactivation code
> snippet. The urb deactivation code has to be performed even after the
> device disconnected. Otherwise it remains undead and pokes the wild
> access in the end.
>
> The regression fix is simply reverting the shutdown flag check in that
> code.
>
> Reported-and-tested-by: Chris J Arges <[email protected]>
> Cc: <[email protected]> [v3.2..v3.4]
> Signed-off-by: Takashi Iwai <[email protected]>
> ---
>
> Looking at linux-stable git tree, 3.2.y and 3.4.y are affected at
> least. Ben, Greg, please apply this.
>
> I'm not sure whether other trees (3.3.y, 3.5.y) already included the
> commit in question (upstream commit 978520b7). Even the tree contains
> its backport, it's not necessarily broken, e.g. 3.7.y doesn't need
> this patch. This patch is only for the broken backport to older
> kernels.
Hi, originally 3.5.y didn't have it, but I applied the backport for 3.6
on 3.5.7.2, which looked correct for 3.5, and doesn't have the
problematic check, so I think it's fine. Thanks for looking into this
issue.
>
> Thanks!
>
> Takashi
>
>
> sound/usb/endpoint.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
> index 24c5114..9ab2b3e 100644
> --- a/sound/usb/endpoint.c
> +++ b/sound/usb/endpoint.c
> @@ -148,10 +148,8 @@ void snd_usb_release_substream_urbs(struct
> snd_usb_substream *subs, int force)
> int i;
>
> /* stop urbs (to be sure) */
> - if (!subs->stream->chip->shutdown) {
> - deactivate_urbs(subs, force, 1);
> - wait_clear_urbs(subs);
> - }
> + deactivate_urbs(subs, force, 1);
> + wait_clear_urbs(subs);
>
> for (i = 0; i < MAX_URBS; i++)
> release_urb_ctx(&subs->dataurb[i]);
> --
> 1.8.1.1
>
--
[]'s
Herton
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
