netdev - Re: [PATCH] net: Add ndo_gso

lists.openwall.net		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 linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20141007.163239.157997964784151921.davem@davemloft.net>
Date:	Tue, 07 Oct 2014 16:32:39 -0400 (EDT)
From:	David Miller <davem@...emloft.net>
To:	alexei.starovoitov@...il.com
Cc:	therbert@...gle.com, jesse@...ira.com, gerlitz.or@...il.com,
	alexander.h.duyck@...el.com, john.r.fastabend@...el.com,
	jeffrey.t.kirsher@...el.com, netdev@...r.kernel.org, tgraf@...g.ch,
	pshelar@...ira.com, azhou@...ira.com
Subject: Re: [PATCH] net: Add ndo_gso_check

From: Alexei Starovoitov <alexei.starovoitov@...il.com>
Date: Tue, 7 Oct 2014 13:28:01 -0700

> On Tue, Oct 7, 2014 at 11:47 AM, David Miller <davem@...emloft.net> wrote:
>>
>> I am totally against boolean "yes/no" protocol specific checksum
>> validation by HW.
>>
>> It's not faster.  You have to look at the pseudo-header and bring it into
>> the CPU cache _anyways_, so negating it and 2's complementing it into
>> the CHECKSUM_COMPLETE value for validation is free.
>>
>> There is no performance advantage whatsoever to use another checksumming
>> scheme.
> 
> ok, forget faster/slower argument for a second.
> Why is it a bad thing to have HW verifying checksums?

Because you have to change the damn hardware and/or firmware for every
new protocol.

COMPLETE works on _EVERYTHING_ we could ever invent.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html