diff options
| author | Marko Ristola <marko.ristola@kolumbus.fi> | 2010-11-14 20:09:04 +0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2010-12-29 13:16:48 +0300 |
| commit | 9c81496a88b04206d0607b23b298b6529da1fcb0 (patch) | |
| tree | 4b8abc23a2d2976129c6837461b207fd98cb85b7 | |
| parent | 116d588ea21cf0278a4de1e3272e9c3220a647e7 (diff) | |
| download | linux-9c81496a88b04206d0607b23b298b6529da1fcb0.tar.xz | |
[media] Mantis: append tasklet maintenance for DVB stream delivery
After dvb-core has called mantis-fe->stop_feed(dvbdmxfeed)
the last time (count to zero), no data should ever be copied
with dvb_dmx_swfilter() by a tasklet: the target structure
might be in an unusable state. Caller of mantis_fe->stop_feed()
assumes that feeding is stopped after stop_feed() has been
called, ie. dvb_dmx_swfilter() isn't running, and won't be called.
There is a risk that dvb_dmx_swfilter() references freed resources
(memory or spinlocks or ???) causing instabilities. Thus
tasklet_disable(&mantis->tasklet) must be called inside of
mantis-fe->stop_feed(dvbdmxfeed) when necessary.
Signed-off-by: Marko Ristola <marko.ristola@kolumbus.fi>
Signed-off-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
| -rw-r--r-- | drivers/media/dvb/mantis/mantis_dvb.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/media/dvb/mantis/mantis_dvb.c b/drivers/media/dvb/mantis/mantis_dvb.c index 99d82eec3b03..a9864f7134e1 100644 --- a/drivers/media/dvb/mantis/mantis_dvb.c +++ b/drivers/media/dvb/mantis/mantis_dvb.c @@ -117,6 +117,7 @@ static int mantis_dvb_start_feed(struct dvb_demux_feed *dvbdmxfeed) if (mantis->feeds == 1) { dprintk(MANTIS_DEBUG, 1, "mantis start feed & dma"); mantis_dma_start(mantis); + tasklet_enable(&mantis->tasklet); } return mantis->feeds; @@ -136,6 +137,7 @@ static int mantis_dvb_stop_feed(struct dvb_demux_feed *dvbdmxfeed) mantis->feeds--; if (mantis->feeds == 0) { dprintk(MANTIS_DEBUG, 1, "mantis stop feed and dma"); + tasklet_disable(&mantis->tasklet); mantis_dma_stop(mantis); } @@ -216,6 +218,7 @@ int __devinit mantis_dvb_init(struct mantis_pci *mantis) dvb_net_init(&mantis->dvb_adapter, &mantis->dvbnet, &mantis->demux.dmx); tasklet_init(&mantis->tasklet, mantis_dma_xfer, (unsigned long) mantis); + tasklet_disable(&mantis->tasklet); if (mantis->hwconfig) { result = config->frontend_init(mantis, mantis->fe); if (result < 0) { |