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: <CAHmME9pP1E64CCc7+XW8X1duYGQZdYj9s_r8UNq3KMh6xey_Hw@mail.gmail.com>
Date:	Thu, 5 Nov 2015 16:00:55 +0100
From:	"Jason A. Donenfeld" <Jason@...c4.com>
To:	Herbert Xu <herbert@...dor.apana.org.au>
Cc:	Netdev <netdev@...r.kernel.org>, linux-kernel@...r.kernel.org
Subject: Re: NETIF_F_GSO_SOFTWARE vs NETIF_F_GSO

Hi Herbert,

Thanks for your response!

On Thu, Nov 5, 2015 at 1:15 PM, Herbert Xu <herbert@...dor.apana.org.au> wrote:
> The NETIF_F_GSO flag turns on software GSO which should be on
> anyway.  So that could be why it seems to make no difference.

GSO is on by default? That makes sense, okay.

>
> NETIF_F_GSO_SOFTWARE is actually a collection of bits that lists
> the protocols for which we support software GSO.  The bits themselves
> are in fact an indication that the hardware supports GSO directly.
> So by turning them on you're electing to receive GSO packets
> directly.

Right -- I saw the expansion in the header file -- it gets the various
TSOs plus UFO. So what this means is that the packet hasn't yet been
split up? So were I to add this option, then my driver would have to
be responsible for splitting up the super-packets manually? In which
case, there would be no performance benefit in using it, since GSO
already does this just prior to ndo_start_xmit? Or would there be a
performance benefit in receiving the super-packets and splitting them
myself?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ