Re: [PATCH net 1/6] hinic: fix process of long length skb without frags

[David Miller]

From: Jakub Kicinski <kuba@xxxxxxxxxx>
Date: Mon, 16 Mar 2020 14:44:08 -0700

> On Mon, 16 Mar 2020 00:56:25 +0000 Luo bin wrote:
>> -#define MIN_SKB_LEN                     17
>> +#define MIN_SKB_LEN			17
>> +#define HINIC_GSO_MAX_SIZE		65536
> 
>> +	if (unlikely(skb->len > HINIC_GSO_MAX_SIZE && nr_sges == 1)) {
>> +		txq->txq_stats.frag_len_overflow++;
>> +		goto skb_error;
>> +	}
> 
> I don't think drivers should have to check this condition.
> 
> We have netdev->gso_max_size which should be initialized to 
> 
> include/linux/netdevice.h:#define GSO_MAX_SIZE          65536
> 
> in
> 
> net/core/dev.c: dev->gso_max_size = GSO_MAX_SIZE;
> 
> Please send a patch to pktgen to uphold the normal stack guarantees.

Agreed, the driver should not have to validate this.