Re: [PATCH] usbnet: do not pretend to support SG/TSO

David Miller
2013-07-26T20:48:41Z

From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 23 Jul 2013 17:15:54 -0700

> From: Eric Dumazet <edumazet@google.com>
>
> usbnet doesn't support yet SG, so drivers should not advertise SG or TSO
> capabilities, as they allow TCP stack to build large TSO packets that
> need to be linearized and might use order-5 pages.
>
> This adds an extra copy overhead and possible allocation failures.
>
> Current code ignore skb_linearize() return code so crashes are even
> possible.
>
> Best is to not pretend SG/TSO is supported, and add this again when/if
> usbnet really supports SG for devices who could get a performance gain.
>
> Based on a prior patch from Freddy Xin <freddy@asix.com.tw>
>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied, thanks Eric.