From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ferruh Yigit <ferruh.yigit@intel.com>
Subject: Re: [RFC] ethdev: add new offload flag to keep CRC
Date: Tue, 19 Jun 2018 13:54:08 +0100
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References: <20180608225709.19473-1-ferruh.yigit@intel.com>
 <20180611082509.4551fac5@xeon-e3>
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Cc: Neil Horman <nhorman@tuxdriver.com>,
 John McNamara <john.mcnamara@intel.com>,
 Marko Kovacevic <marko.kovacevic@intel.com>,
 Thomas Monjalon <thomas@monjalon.net>, dev@dpdk.org
To: Stephen Hemminger <stephen@networkplumber.org>
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On 6/11/2018 4:25 PM, Stephen Hemminger wrote:
> On Fri,  8 Jun 2018 23:57:09 +0100
> Ferruh Yigit <ferruh.yigit@intel.com> wrote:
> 
>> DEV_RX_OFFLOAD_KEEP_CRC offload flag added.
>>
>> DEV_RX_OFFLOAD_CRC_STRIP flag will remain one more release
>> default behavior in PMDs is to keep the CRC until this flag removed
> 
> This won't work for virtual devices that never keep CRC.
> Maybe wording should be changed.

Yes, it won't work for virtual devices, but it is already the case, no offload
flag means keep CRC.

This task is to replace that behavior gradually. What will be replaced is:
flag: DEV_RX_OFFLOAD_CRC_STRIP => DEV_RX_OFFLOAD_KEEP_CRC
default, no flag, behavior : KEEP_CRC => STRIP_CRC

But because of gradually switch, this release, 18.08, both flags will exits and
no flag default still will be KEEP_CRC

For virtual devices, for this release, since virtual PMDs don't announce any CRC
related offload capability, applications can't explicitly request to keep the CRC.
But no flag case (default keep CRC) will be wrong and ignored by virtual PMDs.

on 18.11 when DEV_RX_OFFLOAD_CRC_STRIP is removed and default behavior is STRIP
CRC, it will be correct for virtual device.