From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH v1 net-next 12/14] igb: Only call skb_tx_timestamp after
 descriptors are ready
Date: Wed, 27 Jun 2018 16:56:27 -0700
Message-ID: <44770d6b-503c-279f-807f-0b7f11be56cf@gmail.com>
References: <20180627215950.6719-1-jesus.sanchez-palencia@intel.com>
 <20180627215950.6719-13-jesus.sanchez-palencia@intel.com>
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To: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>,
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On 06/27/2018 02:59 PM, Jesus Sanchez-Palencia wrote:
> Currently, skb_tx_timestamp() is being called before the DMA
> descriptors are prepared in igb_xmit_frame_ring(), which happens
> during either the igb_tso() or igb_tx_csum() calls.
> 
> Given that now the skb->tstamp might be used to carry the timestamp
> for SO_TXTIME, we must only call skb_tx_timestamp() after the
> information has been copied into the DMA tx_ring.


Since when this skb->tstamp use happened ?

If this is in patch 11/14 (igb: Add support for ETF offload), then you should either :

1) Squash this into 11/14

2) swap 11 and 12 patch, so that this change is done before "igb: Add support for ETF offload"  

Otherwise a bisection could fail badly.