From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] tls: Skip zerocopy path for ITER_KVEC
Date: Tue, 24 Jul 2018 14:38:02 -0700 (PDT)
Message-ID: <20180724.143802.309217898930041106.davem@davemloft.net>
References: <20180720181900.1073485-1-doronrk@fb.com>
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From: Doron Roberts-Kedes <doronrk@fb.com>
Date: Fri, 20 Jul 2018 11:19:00 -0700

> The zerocopy path ultimately calls iov_iter_get_pages, which defines the
> step function for ITER_KVECs as simply, return -EFAULT. Taking the
> non-zerocopy path for ITER_KVECs avoids the unnecessary fallback. 
> 
> See https://lore.kernel.org/lkml/20150401023311.GL29656@ZenIV.linux.org.uk/T/#u
> for a discussion of why zerocopy for vmalloc data is not a good idea. 
> 
> Discovered while testing NBD traffic encrypted with ktls.
> 
> Fixes: c46234ebb4d1 ("tls: RX path for ktls")
> Signed-off-by: Doron Roberts-Kedes <doronrk@fb.com>

Applied to net-next, thanks.