g; driverdev-
> de...@linuxdriverproject.org
> Subject: Re: [PATCH net-next] hyperv: Add processing of MTU reduced by
> the host
>
> From: Haiyang Zhang
> Date: Tue, 11 Nov 2014 15:27:52 -0800
>
> > - if (mtu < 68 || mtu > limit)
> > + if (mtu < ETH_DATA_LEN || mtu >
g; driverdev-
> de...@linuxdriverproject.org
> Subject: Re: [PATCH net-next] hyperv: Add processing of MTU reduced by
> the host
>
> From: Haiyang Zhang
> Date: Wed, 12 Nov 2014 20:02:11 +
>
> > The Hyper-V host doesn't support MTU below 1500. If we try setting MTU
> to a
>
From: Haiyang Zhang
Date: Wed, 12 Nov 2014 20:02:11 +
> The Hyper-V host doesn't support MTU below 1500. If we try setting MTU to a
> value < 1500, the host will use 1500 automatically and return 1500 in the
> RNDIS_OID_GEN_MAXIMUM_FRAME_SIZE query and guest will also use it. That's
> why
From: Haiyang Zhang
Date: Tue, 11 Nov 2014 15:27:52 -0800
> - if (mtu < 68 || mtu > limit)
> + if (mtu < ETH_DATA_LEN || mtu > limit)
> return -EINVAL;
This is not correct.
The test is against the minimally supported MTU, which should
be 68 not ETH_DATA_LEN which is 1500.
If the host uses packet encapsulation feature, the MTU may be reduced by the
host due to headroom reservation for encapsulation. This patch handles this
new MTU value.
Signed-off-by: Haiyang Zhang
---
drivers/net/hyperv/netvsc.c |3 ++-
drivers/net/hyperv/netvsc_drv.c |4 ++--
dr
