From: Eric Dumazet <eric.duma...@gmail.com>
Date: Sun, 01 Nov 2015 09:20:59 -0800
> From: Eric Dumazet <eduma...@google.com>
>
> My recent commit, attaching SYNACK messages to request sockets
> exposed a too small LL_MAX_HEADER when netvsc_drv.c is in use,
> because this driver sets a needed_headroom of 220 bytes.
>
> Increase LL_MAX_HEADER in this case, to avoid a realloc of all
> TCP frames.
>
> In another patch, I'll make skb_set_owner_w() more robust.
>
> Fixes: ca6fb0651883 ("tcp: attach SYNACK messages to request sockets instead
> of listener")
> Signed-off-by: Eric Dumazet <eduma...@google.com>
> Bisected-by: Haiyang Zhang <haiya...@microsoft.com>
Using a value of 256 just because HYPER-V is crazy imposes a huge
unnecessary burdon upon the rest of the stack.
I rejected a previous attempt to use such a huge value for
LL_MAX_HEADER, and I will do so again here. We need a different fix
for this issue, one that doesn't hurt everyone.
Every distribution is going to turn all the options on, so you might
as well consider the largest LL_MAX_HEADER value the one %99.999
users end up paying the price for.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
