From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v3 net-next 13/21] net: usb: aqc111: Add support for TSO
Date: Thu, 22 Nov 2018 11:17:21 -0800 (PST)
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From: Igor Russkikh <Igor.Russkikh@aquantia.com>
Date: Wed, 21 Nov 2018 10:13:48 +0000

> @@ -832,6 +832,10 @@ static struct sk_buff *aqc111_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
>  	/*Length of actual data*/
>  	tx_desc |= skb->len & AQ_TX_DESC_LEN_MASK;
>  
> +	/* TSO MSS */
> +	tx_desc |= ((u64)(skb_shinfo(skb)->gso_size & AQ_TX_DESC_MSS_MASK)) <<
> +		   AQ_TX_DESC_MSS_SHIFT;
 ...
> +#define AQ_TX_DESC_MSS_MASK	0x7FFF

This implies a GSO size limit, which you need to advertise properly in
netdevice->gso_max_size.

Also, where is the TSO feature flag being set to actually enable the
stack sending your GSO frames?