ppp_async kfree patch

ppp_async kfree patch

[Gilles Espinasse]

It has been reported in this thread
https://sourceforge.net/tracker/index.php?funcÞtail&aid\x1678777&group_id@604&atidB8519

that a one line patch on ppp_async avoid crash and reboot

This happen with hight speed connection and usbserial using
http://www.junxion.com/opensource/linux_highspeed_usbserial.html patch

Here is the patch against 2.4.34 a few lines after  We have finished the
packet.
Code is the same on 2.6.22 and look not have been changed until 2.6.23.rc3

--- linux-2.4.34/drivers/net/ppp_async.c.old 2007-06-30 17:56:40.000000000
-0700
+++ linux-2.4.34/drivers/net/ppp_async.c 2007-06-30 17:57:07.000000000
-0700
@@ -624,7 +624,7 @@
  *buf++ = PPP_FLAG;
  ap->olim = buf;

- kfree_skb(ap->tpkt);
+ dev_kfree_skb_any(ap->tpkt);
  ap->tpkt = 0;
  return 1;
 }

Comment welcome.

Gilles

Re: ppp_async kfree patch

[James Cameron]

G'day Gilles,

I'll test this patch.

I've been having almost daily hangs or loss of receive data on a system
that has a USB HSDPA modem using the airprime driver, with an instance
of PPP for the modem, an instance of PPP used by PPTP, and one for an
SSH over PPP tunnel.  So the probability of the event is increased.

-- 
James Cameron                         http://quozl.netrek.org/
HP Open Source, Volunteer             http://opensource.hp.com/
PPTP Client Project, Release Engineer http://pptpclient.sourceforge.net/

Re: ppp_async kfree patch

[James Cameron]

This patch has fixed the kernel hangs I had been having on a system
using three instances of pppd a USB HSDPA modem.

In the situations where the hang would normally occur, what I now see is
disconnection and reconnection of the USB device, apparently triggered
by electrical noise or RF interference.

I presume that what was happening before this patch was that the
disconnection of the USB device caused a deadlock, associated with this
area of ppp_async.

-- 
James Cameron                         http://quozl.netrek.org/
HP Open Source, Volunteer             http://opensource.hp.com/
PPTP Client Project, Release Engineer http://pptpclient.sourceforge.net/