lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Date:	Thu, 19 Jul 2007 08:35:14 -0500
From:	Brian King <>
To:	Jeff Garzik <>
Subject: Re: [PATCH 1/4] ibmveth: Enable TCP checksum offload

Jeff Garzik wrote:
> Brian King wrote:
>> This patchset enables TCP checksum offload support for IPV4
>> on ibmveth. This completely eliminates the generation and checking of
>> the checksum for packets that are completely virtual and never
>> touch a physical network. A simple TCP_STREAM netperf run on
>> a virtual network with maximum mtu set yielded a ~30% increase
>> in throughput. This feature is enabled by default on systems that
>> support it, but can be disabled with a module option.
>> Signed-off-by: Brian King <>
> this should be controllable purely via ethtool...

I'll remove the module parameter and resend.

>>  struct ibmveth_rx_q_entry {
>>      u16 toggle : 1;
>>      u16 valid : 1;
>> -    u16 reserved : 14;
>> +    u16 reserved : 4;
>> +    u16 no_csum : 1;
>> +    u16 csum_good : 1;
>> +    u16 reserved2 : 8;
>>      u16 offset;
> As a general rule, it would be nice to start moving away from bitfields 
> in this driver

I'll take a look at that for a future cleanup patch.



Brian King
Linux on Power Virtualization
IBM Linux Technology Center
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to
More majordomo info at

Powered by blists - more mailing lists