Re: [patch v2] [media] bttv: take correct lock in bttv_open()

[Sergej Pupykin <pupykin.s@gmail.com>]

On 12.12.2010 19:58, Dan Carpenter wrote:
> We're trying to make sure that no one is writing to the btv->init struct
> while we copy it over to the newly allocated "fh" struct.  The original
> code doesn't make sense because "fh->cap.vb_lock" hasn't been
> initialized and no one else can be writing to it anyway.
>
This patch also crashes the system. Unfortunately machine hangs, so I 
can not copy-paste trace. It was something about nosemaphore called from 
bttv_open. (something like previous reports)

I replace lock with btv->lock:

mutex_lock(&btv->lock);
*fh = btv->init;
mutex_unlock(&btv->lock);

Probably it is overkill and may be incorrect, but it starts working.

Also I found another issue: tvtime hangs on exit in D-state, so it looks 
like there is a problem near bttv_release function or something like this.