The patch number 9029 was added via Mauro Carvalho Chehab <[EMAIL PROTECTED]>
to http://linuxtv.org/hg/v4l-dvb master development tree.
Kernel patches in this development tree may be modified to be backward
compatible with older kernels. Compatibility modifications will be
removed before inclusion into the mainstream Kernel
If anyone has any objections, please let us know by sending a message to:
[EMAIL PROTECTED]
------
From: Andreas Oberritter <[EMAIL PROTECTED]>
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 <[EMAIL PROTECTED]>
Signed-off-by: Mauro Carvalho Chehab <[EMAIL PROTECTED]>
---
linux/drivers/media/dvb/dvb-core/dmxdev.c | 16 +++++++++-------
linux/drivers/media/dvb/dvb-core/dvb_demux.c | 16 ++++++++++------
2 files changed, 19 insertions(+), 13 deletions(-)
diff -r afd0871f664a -r aa3e5cc1d833 linux/drivers/media/dvb/dvb-core/dmxdev.c
--- a/linux/drivers/media/dvb/dvb-core/dmxdev.c Sun Sep 14 22:49:14 2008 +0200
+++ b/linux/drivers/media/dvb/dvb-core/dmxdev.c Wed Sep 24 10:00:37 2008 +0200
@@ -364,15 +364,16 @@ static int dvb_dmxdev_section_callback(c
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(c
}
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
{
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
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
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;
}
diff -r afd0871f664a -r aa3e5cc1d833
linux/drivers/media/dvb/dvb-core/dvb_demux.c
--- a/linux/drivers/media/dvb/dvb-core/dvb_demux.c Sun Sep 14 22:49:14
2008 +0200
+++ b/linux/drivers/media/dvb/dvb-core/dvb_demux.c Wed Sep 24 10:00:37
2008 +0200
@@ -399,7 +399,9 @@ void dvb_dmx_swfilter_packets(struct dvb
void dvb_dmx_swfilter_packets(struct dvb_demux *demux, const u8 *buf,
size_t count)
{
- spin_lock(&demux->lock);
+ unsigned long flags;
+
+ spin_lock_irqsave(&demux->lock, flags);
while (count--) {
if (buf[0] == 0x47)
@@ -407,16 +409,17 @@ void dvb_dmx_swfilter_packets(struct dvb
buf += 188;
}
- spin_unlock(&demux->lock);
+ spin_unlock_irqrestore(&demux->lock, flags);
}
EXPORT_SYMBOL(dvb_dmx_swfilter_packets);
void dvb_dmx_swfilter(struct dvb_demux *demux, const u8 *buf, size_t count)
{
+ unsigned long flags;
int p = 0, i, j;
- spin_lock(&demux->lock);
+ spin_lock_irqsave(&demux->lock, flags);
if (demux->tsbufp) {
i = demux->tsbufp;
@@ -449,17 +452,18 @@ void dvb_dmx_swfilter(struct dvb_demux *
}
bailout:
- spin_unlock(&demux->lock);
+ spin_unlock_irqrestore(&demux->lock, flags);
}
EXPORT_SYMBOL(dvb_dmx_swfilter);
void dvb_dmx_swfilter_204(struct dvb_demux *demux, const u8 *buf, size_t count)
{
+ unsigned long flags;
int p = 0, i, j;
u8 tmppack[188];
- spin_lock(&demux->lock);
+ spin_lock_irqsave(&demux->lock, flags);
if (demux->tsbufp) {
i = demux->tsbufp;
@@ -500,7 +504,7 @@ void dvb_dmx_swfilter_204(struct dvb_dem
}
bailout:
- spin_unlock(&demux->lock);
+ spin_unlock_irqrestore(&demux->lock, flags);
}
EXPORT_SYMBOL(dvb_dmx_swfilter_204);
---
Patch is available at:
http://linuxtv.org/hg/v4l-dvb/rev/aa3e5cc1d83321e4b43fe1129e6c4882746e03ea
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