Subject: Re: r8169: instant crash if receiving packet larger than MTU

From: Michael Tokarev <[email-masked]>
Date: Tue, 17 Feb 2009 23:55:19 +0300

Francois Romieu wrote:
> Michael Tokarev <[email-masked]> :
>> I played with jumbo frames today at home on two
>> machines with built-in r8169 NICs.  And discovered
>> that, after enabling larger packets on one machine,
>> it's sufficient to send SINGLE packet to immediately,
>> instantly crash the other machine.
> 
> Which size did you use and how did it crash (dead keyboard leds
> without any message in the console ?) ?

Original interface MTU was unchanged from the default 1500 bytes.
The packet I sent was of size 8000 bytes.

The crash - one of the machines in question was completely dead,
nothing on the console, and dead keyboard leds.  Another with the
same chip rebooted instantly.

/mjt