From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] USBNET: fix handling padding packet
Date: Wed, 18 Sep 2013 12:12:17 -0400 (EDT)
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=46rom: Bj=F8rn Mork <bjorn@mork.no>
Date: Wed, 18 Sep 2013 17:52:42 +0200

> Ming Lei <ming.lei@canonical.com> writes:
>=20
>> There is no reason to forbid DMA SG for one driver which requires
>> padding, right?
>=20
> Yes there is: Added complexity for everybody, based on a combination =
of
> features which just does not make any sense.
>=20
> No modern device should need the padding.  No old device will be able=
 to
> use the SG feature as implemented. You only enable it on USB3, don't
> you? If this feature is restricted to USB3 capable devices, then it m=
ost
> certainly can be restricted to ZLP capable devices with absolutely no
> difference in the resulting set of supported devices.

I completely agree.