kern/141843: [em] [vlan] Intel txcsum and assigned vlan invoke wrong dst MAC in TCP packets

[Jean-Luc Richier]

The following reply was made to PR kern/141843; it has been noted by GNATS.

From: Jean-Luc Richier <Jean-Luc.Richier at imag.fr>
To: bug-followup at FreeBSD.org, dyr at smartspb.net
Cc:  
Subject: Re: kern/141843: [em] [vlan] Intel txcsum and assigned vlan invoke
 wrong dst MAC in TCP packets
Date: Wed, 24 Feb 2010 09:19:29 +0100

 A other cause (or the same) seems that when the interface is reset (for 
 example with a ifconfig em0 down, the chip is reset, but the 
 last_hw_offload in the interface context is not reset
 
 I just had the following problem in FreeBSD8.0 RELEASE
 # ping www.google.com
 	It works
 # ifconfig em0 down up
 # ping www.google.com
 	It does not work
 # telnet -N <ipv4 router addr>
 	Normal error message
 # ping www.google.com
 	It works
 
 I made the following path to solve the problem (in em_stop):
 
 --- /sys/dev/e1000/if_em.c.DIST 2009-10-25 02:10:29.000000000 +0100
 +++ /sys/dev/e1000/if_em.c      2010-02-23 18:22:53.000000000 +0100
 @@ -2710,6 +2710,7 @@
          ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
 
          e1000_reset_hw(&adapter->hw);
 +       adapter->last_hw_offload = 0;
          if (adapter->hw.mac.type >= e1000_82544)
                  E1000_WRITE_REG(&adapter->hw, E1000_WUC, 0);
   }
 
 
 
 
 -- 
 Jean-Luc RICHIER (Jean-Luc.Richier at Imag.Fr)
 Laboratoire d'Informatique de Grenoble (LIG)
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