Re: [dpdk-dev] [PATCH 2/2] net/virtio: fix Tx completed mbufs leak on device stop

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

On 9/13/21 6:41 PM, Maxime Coquelin wrote:
> 
> 
> On 8/18/21 4:13 PM, Andrew Rybchenko wrote:
>> From: Ivan Ilchenko <ivan.ilchenko@oktetlabs.ru>
>>
>> Free Tx completed mbufs on device stop. Not completed Tx mbufs cannot be
>> freed since they are still in use.
>>
>> Fixes: c1f86306a02 ("virtio: add new driver")
>> Cc: stable@dpdk.org
>>
>> Signed-off-by: Ivan Ilchenko <ivan.ilchenko@oktetlabs.ru>
>> Signed-off-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
>> ---
>>  drivers/net/virtio/virtio_ethdev.c | 30 ++++++++++++++++++++++++++++++
>>  1 file changed, 30 insertions(+)
>>
>> diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
>> index e58085a2c9..ed3fefee7c 100644
>> --- a/drivers/net/virtio/virtio_ethdev.c
>> +++ b/drivers/net/virtio/virtio_ethdev.c
>> @@ -2393,6 +2393,34 @@ static void virtio_dev_free_mbufs(struct rte_eth_dev *dev)
>>  	PMD_INIT_LOG(DEBUG, "%d mbufs freed", mbuf_num);
>>  }
>>  
>> +static void
>> +virtio_tx_completed_cleanup(struct rte_eth_dev *dev)
>> +{
>> +	struct virtio_hw *hw = dev->data->dev_private;
>> +	struct virtqueue *vq;
>> +	int qidx;
>> +	void (*xmit_cleanup)(struct virtqueue *vq, uint16_t nb_used);
>> +
>> +	if (virtio_with_packed_queue(hw)) {
>> +		if (hw->use_vec_tx)
>> +			xmit_cleanup = &virtio_xmit_cleanup_inorder_packed;
>> +		else if (virtio_with_feature(hw, VIRTIO_F_IN_ORDER))
>> +			xmit_cleanup = &virtio_xmit_cleanup_inorder_packed;
>> +		else
>> +			xmit_cleanup = &virtio_xmit_cleanup_normal_packed;
>> +	} else {
>> +		if (hw->use_inorder_tx)
>> +			xmit_cleanup = &virtio_xmit_cleanup_inorder;
>> +		else
>> +			xmit_cleanup = &virtio_xmit_cleanup;
>> +	}
>> +
>> +	for (qidx = 0; qidx < hw->max_queue_pairs; qidx++) {
>> +		vq = hw->vqs[2 * qidx + VTNET_SQ_TQ_QUEUE_IDX];
> 
> Maybe add a check to ensure that vq is non-NULL since it is dereferenced
> later without checking.

Good idea, I'll send v2.

> 
>> +		xmit_cleanup(vq, virtqueue_nused(vq));
>> +	}
>> +}
>> +
>>  /*
>>   * Stop device: disable interrupt and mark link down
>>   */
>> @@ -2411,6 +2439,8 @@ virtio_dev_stop(struct rte_eth_dev *dev)
>>  		goto out_unlock;
>>  	hw->started = 0;
>>  
>> +	virtio_tx_completed_cleanup(dev);
>> +
>>  	if (intr_conf->lsc || intr_conf->rxq) {
>>  		virtio_intr_disable(dev);
>>  
>>