Re: PPP with PCMCIA modem stalls on 2.6.10 or later

[Paul Fulghum <paulkf@microgate.com>]

On Wed, 2006-02-15 at 00:57 +0900, Kouji Toriatama wrote:
> Following is a status of ppp0 interface when the above wget
> command finished.  The count of RX errors, RX bytes and TX
> bytes has sometimes increased while stalling.  In kernel
> 2.6.9, the count of Rx errors was 0.
> -------------------------------------------------------------
> ppp0      Link encap:Point-to-Point Protocol  
>           inet addr:202.179.209.95  P-t-P:172.24.24.22  Mask:255.255.255.255
>           UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
>           RX packets:44 errors:18 dropped:0 overruns:0 frame:0
>           TX packets:50 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:3 
>           RX bytes:15992 (15.6 KiB)  TX bytes:2544 (2.4 KiB)

In 2.6.10, a new check for errors on received characters was added.

Try the patch below. It prevents the check from discarding
received frames, but outputs an error message to the syslog.

Run with the patch and return the results with
any syslog output containing the error message.

Thanks,
Paul

--- linux-2.6.15/drivers/net/ppp_async.c	2006-01-02 21:21:10.000000000 -0600
+++ b/drivers/net/ppp_async.c	2006-02-14 11:04:47.000000000 -0600
@@ -923,8 +923,9 @@ ppp_async_input(struct asyncppp *ap, con
 
 		c = buf[n];
 		if (flags != NULL && flags[n] != 0) {
-			ap->state |= SC_TOSS;
-		} else if (c == PPP_FLAG) {
+			printk("ppp_async:bad char c=%02X f=%02X\n", buf[n], flags[n]);
+		} 
+		if (c == PPP_FLAG) {
 			process_input_packet(ap);
 		} else if (c == PPP_ESCAPE) {
 			ap->state |= SC_ESCAPE;