From mboxrd@z Thu Jan  1 00:00:00 1970
From: Boris Pismenny <borisp@mellanox.com>
Subject: Re: [net-next v3 1/5] net/tls: Do not enable zero-copy prematurely
Date: Thu, 19 Jul 2018 06:28:05 -0400
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References: <20180719111643.12787-1-vakul.garg@nxp.com>
 <20180719111643.12787-2-vakul.garg@nxp.com>
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To: Vakul Garg <vakul.garg@nxp.com>, netdev@vger.kernel.org
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Hi Vakul,

On 7/19/2018 7:16 AM, Vakul Garg wrote:
> Zero-copy mode was left enabled even when zerocopy_from_iter() failed.
> Set the zero-copy mode only when zerocopy_from_iter() succeeds. This
> leads to removal of argument 'zc' of function decrypt_skb_update().
> Function decrypt_skb_update() does not need to check whether
> ctx->decrypted is set since it is never called if ctx->decrypted is
> true.
> 

This patch breaks our tls_device code for the following 2 reasons:
1. We need to disable zerocopy if the device decrypted the record, 
because decrypted data has to be copied to user buffers.
2. ctx->decrypted must be checked in decrypt_skb_update, because it 
might change after calling tls_device_decrypted.