[linux-dvb] problems and workaround when tuning to a channel with DD enabled

Dr. Werner Fink werner at suse.de
Thu Jun 16 16:24:11 CEST 2005


On Thu, Jun 16, 2005 at 04:07:17PM +0200, Johannes Stezenbach wrote:
> On Thu, Jun 16, 2005 at 06:48:55AM +0200, Oliver Endriss wrote:
> > 
> > Looks ok if OSDSetBlock is _never_ used by more than one thread at the
> > same time. Otherwise, some race conditions might occur.
> > 
> > Anyway, as the OSD interface has state variables like av7110->osdwin
> > it is not thread-safe 'by design'.
> 
> av7110_osd_cmd() is protected by av7110->osd_sema. Where
> do you think there is a race condition?

If really a preemptiv kernel is used not only the
user space access but also tasklets may matter.

        Werner

-- 
AC3 loop through sound card http://bitstreamout.sourceforge.net/
Howto http://www.vdr-portal.de/board/thread.php?threadid=1958
------------------------------------------------------------------
 "Having a smoking section in a restaurant is like having
         a  peeing section in a swimming pool." -- Edward Burr




More information about the linux-dvb mailing list