Re: [PATCH v1 net-next 12/14] igb: Only call skb_tx_timestamp after descriptors are ready

[Eric Dumazet]

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.