Hi Paul,
This has been discussed on these lists since some time already, but as we
don't seem to come to a proper fix, I decided to summarize our problem
once again.
A short summary from the ppp PoV:
ppp_push()
{
spin_lock_bh(&pch->downl);
pch->chan->ops->start_xmit(pch->chan, skb)
{
...
ppp_output_wakeup()
{
ppp_channel_push()
{
spin_lock_bh(&pch->downl);
BANG!...
This happens with IrNET. So, the question is, is it legitimate to call
ppp_channel_push() from the .start_xmit() method? How do other ppp drivers
do it? Looks like, for examplke, ppp_async checks explicitly for
recursion, synctty does a try_spinlock_bh()... Is it just a bug in IrNET
and one just cannot do this, or is there a simple fix for this?
Samuel's suggestion is to offload the call to ppp_output_wakeup() to the
keventd workqueue, but we haven't been able to make this work properly so
far.
I have a dirty workaround, whereby I explicitly verify recursion in
ppp_channel_push(). This works, but it doesn't seem to be a good solution.
Thanks
Guennadi
---------------------------------
Guennadi Liakhovetski, Ph.D.
DSA Daten- und Systemtechnik GmbH
Pascalstr. 28
D-52076 Aachen
Germany
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
