V4L/DVB (9029): Fix deadlock in demux code

The functions dvb_dmxdev_section_callback, dvb_dmxdev_ts_callback,
dvb_dmx_swfilter_packet, dvb_dmx_swfilter_packets, dvb_dmx_swfilter and
dvb_dmx_swfilter_204 may be called from both interrupt and process
context. Therefore they need to be protected by spin_lock_irqsave()
instead of spin_lock().

This fixes a deadlock discovered by lockdep.

Signed-off-by: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Andreas Oberritter
2008-09-24 05:00:37 -03:00
committed by Mauro Carvalho Chehab
parent 3d843c92da
commit dda06a8e46
2 changed files with 19 additions and 13 deletions

View File

@@ -364,15 +364,16 @@ static int dvb_dmxdev_section_callback(const u8 *buffer1, size_t buffer1_len,
enum dmx_success success)
{
struct dmxdev_filter *dmxdevfilter = filter->priv;
unsigned long flags;
int ret;
if (dmxdevfilter->buffer.error) {
wake_up(&dmxdevfilter->buffer.queue);
return 0;
}
spin_lock(&dmxdevfilter->dev->lock);
spin_lock_irqsave(&dmxdevfilter->dev->lock, flags);
if (dmxdevfilter->state != DMXDEV_STATE_GO) {
spin_unlock(&dmxdevfilter->dev->lock);
spin_unlock_irqrestore(&dmxdevfilter->dev->lock, flags);
return 0;
}
del_timer(&dmxdevfilter->timer);
@@ -391,7 +392,7 @@ static int dvb_dmxdev_section_callback(const u8 *buffer1, size_t buffer1_len,
}
if (dmxdevfilter->params.sec.flags & DMX_ONESHOT)
dmxdevfilter->state = DMXDEV_STATE_DONE;
spin_unlock(&dmxdevfilter->dev->lock);
spin_unlock_irqrestore(&dmxdevfilter->dev->lock, flags);
wake_up(&dmxdevfilter->buffer.queue);
return 0;
}
@@ -403,11 +404,12 @@ static int dvb_dmxdev_ts_callback(const u8 *buffer1, size_t buffer1_len,
{
struct dmxdev_filter *dmxdevfilter = feed->priv;
struct dvb_ringbuffer *buffer;
unsigned long flags;
int ret;
spin_lock(&dmxdevfilter->dev->lock);
spin_lock_irqsave(&dmxdevfilter->dev->lock, flags);
if (dmxdevfilter->params.pes.output == DMX_OUT_DECODER) {
spin_unlock(&dmxdevfilter->dev->lock);
spin_unlock_irqrestore(&dmxdevfilter->dev->lock, flags);
return 0;
}
@@ -417,7 +419,7 @@ static int dvb_dmxdev_ts_callback(const u8 *buffer1, size_t buffer1_len,
else
buffer = &dmxdevfilter->dev->dvr_buffer;
if (buffer->error) {
spin_unlock(&dmxdevfilter->dev->lock);
spin_unlock_irqrestore(&dmxdevfilter->dev->lock, flags);
wake_up(&buffer->queue);
return 0;
}
@@ -428,7 +430,7 @@ static int dvb_dmxdev_ts_callback(const u8 *buffer1, size_t buffer1_len,
dvb_ringbuffer_flush(buffer);
buffer->error = ret;
}
spin_unlock(&dmxdevfilter->dev->lock);
spin_unlock_irqrestore(&dmxdevfilter->dev->lock, flags);
wake_up(&buffer->queue);
return 0;
}