From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH v2] net/tap: add CRC stripping capability
Date: Thu, 15 Feb 2018 13:55:58 -0800
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Cc: Ophir Munk <ophirmu@mellanox.com>, dev@dpdk.org, Pascal Mazon
 <pascal.mazon@6wind.com>, Olga Shern <olgas@mellanox.com>, stable@dpdk.org
To: Thomas Monjalon <thomas@monjalon.net>
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On Tue, 13 Feb 2018 17:35:20 +0100
Thomas Monjalon <thomas@monjalon.net> wrote:

> 13/02/2018 09:14, Ophir Munk:
> > CRC stripping is executed in the kernel outside of TAP PMD scope.
> > There is no prevention that the TAP PMD will report on Rx CRC
> > stripping capability.
> > In the corrupted code, TAP PMD did not report on this capability.
> > The fix enables TAP PMD to report that Rx CRC stripping is supported.
> > 
> > Fixes: 02f96a0a82d1 ("net/tap: add TUN/TAP device PMD")
> > Cc: stable@dpdk.org
> > 
> > Signed-off-by: Ophir Munk <ophirmu@mellanox.com>  
> 
> Applied, thanks
> 

The whole CRC strip flag notion is backwards. It really should of been
a bit set if driver allows preserving CRC.

Since changing the ABI is not possible right now;
the ethdev core ought to log a warning whenever driver is registered
without CRC_STRIP flag.

Or is lack of CRC_STRIP in offload flags implying that driver can
do strip and not stripping?