ibm_newemac tx problem with jumbo frame enabled

[Prashant Bhole]

On Fri, Nov 25, 2011 at 10:55 AM, Benjamin Herrenschmidt
<benh at kernel.crashing.org> wrote:
> On Fri, 2011-11-18 at 10:33 +0530, Prashant Bhole wrote:
>> Hi,
>> I have been facing problem with ibm_newemac driver (v3.54).
>> The board gets disconnected and can not be pinged in between
>> some heavy network traffic. In my case I am running IOmeter
>> "All-in-One" 8 threads on the iSCSI target. MTU is 4088.
>>
>> I found that after executing emac_full_tx_reset(), the board can
>> be pinged again. Again after some heavy traffic of 5-6 seconds,
>> traffic stops. This can be repeated after full tx reset.
>>
>> Is this a known issue? what could cause this?
>> Any pointers would be greatly appreciated.
>
> Not that I know of. Can you check if any of the error reporting
> registers trip anything ? Could it just be a fifo overflow which we may
> not be handling properly in the driver ?
>
> Cheers,
> Ben.

Still couldn't find anything like fifo overflow...
I noticed one more thing, this problem happens only when mtu size on
the initiator (the other end) is set to 4088, regardless of any mtu size set
for EMAC.


-
Prashant