PROBLEM: TCP keepalive probe count

[Veeriah Vijay-A19819]

I am using 2.4.7 kernel and seem to have a problem where my TCP connection aborts when both the 
client and the server are, perfectly fine, up and running and sending data to each other. 

I was able to reproduce this problem by doing the following.
I  setup the tcp parameters to be as follows :
              tcp_keepalive_time =  2
              tcp_keepalive_probes = 1
              tcp_keepalive_intvl = 3
My server and client send data to each other every 2 seconds.

>From tcpdump output I figured out the following.  After a keepalive_probe is sent out (at the expiry of  keepalive_time)
if it is immediately followed by some valid data, then the ack for the keepalive_probe from the remote side does 
not seem to reset the probes_out to 0. Because of  this when the keepalive_timer expires the next time it RSTs the
connection.
The following code in tcp_input.c, seems to be the problem
	if ((prior_packets = tp->packets_out) == 0)
		goto no_queue;
            ....
	          return 1;

            no_queue:
                      tp->probes_out = 0
            ....

Since in my case prior_packets is not 0, because of the valid data, probes_out is not being reset.
Can somebody let me know  if  I am missing something here or is it a genuine problem that has been fixed in
a later release.

Thanks,
Vijay


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