Network Server Ankh

Ajith Whowe ajith.whowe at gmail.com
Sat Feb 8 18:01:49 CET 2014


Dear Martin,

These commands indicate that the link is always down with the
"NO-CARRIER" flag. Please kindly refer to the outputs given below.
This flag is set by the function "update_carrier", which checks 3
conditions, namely the i) priv->remote_attached ii)
l4shmc_is_chunk_ready(&priv->tx_chunk) iii)
l4shmc_is_chunk_ready(&priv->rx_chunk). Unfortunately the problem is
originated at check point "l4shmc_is_chunk_ready". This function
returns 0, the if clause fails and sets the link down.

I just removed this check point from the if clause, set the link_up to
1 and observed that the ping request showed that the
l4x_l4shmc_xmit_frame function is called. Nevertheless still no answer
back from the second instance.

What can be the main reason for the l4x_l4shmc_xmit_frame to return 0?

Best Regards and many Thanks in Advance,

The result for the "ip addr show" is as follows:

XXXXX - XXXX: Inside l4x_l4shmc_get_stats function - start
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 52:54:00:b0:cf:02 brd ff:ff:ff:ff:ff:ff
    inet 192.168.124.116/24 scope global eth0
    inet 192.168.0.5/24 scope global eth0:0


The result for the "ip link show" is as follows:

XXXXX - XXXX: Inside l4x_l4shmc_get_stats function - start
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 52:54:00:b0:cf:02 brd ff:ff:ff:ff:ff:ff


Hi Ajith,

Am 07.02.2014 17:58, schrieb Ajith Whowe:
>* Dear Martin,
*>>* Thanks a lot. It did the job. I have the network interfaces on both
*>* sides. Nevertheless I can not ping one another. The strange thing is the
*>* ping request clearly does invoke any of the net_device_ops:
*>>* static const struct net_device_ops l4shmnet_netdev_ops = {
*>* .ndo_open       = l4x_l4shmc_open,
*>* .ndo_start_xmit = l4x_l4shmc_xmit_frame,
*>* .ndo_stop       = l4x_l4shmc_close,
*>* .ndo_change_mtu = l4x_l4shmc_change_mtu,
*>* .ndo_get_stats  = l4x_l4shmc_get_stats,
*>>* };
*>>* I put in all these functions some printk's and I can not see it once the
*>* ping starts.
*>>* I also did with -I option like: ping 192.168.1.2 -I eth0  but still no
*>* success.
*>* Do You have any idea?
*
If none of the functions are called, the packet get not through the IP
stack. Can you post the IP configuration (ip addr show and ip link show)
of of both partitions?


Martin
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