[dpdk-dev] [dpdk-stable] [PATCH v3 1/7] ethdev: fix port data reset timing

Ferruh Yigit ferruh.yigit at intel.com
Mon Mar 5 16:06:35 CET 2018


On 3/5/2018 2:52 PM, Matan Azrad wrote:
> HI
> 
> From: Ferruh Yigit, Sent: Monday, March 5, 2018 1:24 PM
>> On 1/18/2018 4:35 PM, Matan Azrad wrote:
>>> rte_eth_dev_data structure is allocated per ethdev port and can be
>>> used to get a data of the port internally.
>>>
>>> rte_eth_dev_attach_secondary tries to find the port identifier using
>>> rte_eth_dev_data name field comparison and may get an identifier of
>>> invalid port in case of this port was released by the primary process
>>> because the port release API doesn't reset the port data.
>>>
>>> So, it will be better to reset the port data in release time instead
>>> of allocation time.
>>>
>>> Move the port data reset to the port release API.
>>>
>>> Fixes: d948f596fee2 ("ethdev: fix port data mismatched in multiple
>>> process model")
>>> Cc: stable at dpdk.org
>>>
>>> Signed-off-by: Matan Azrad <matan at mellanox.com>
>>> ---
>>>  lib/librte_ether/rte_ethdev.c | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/lib/librte_ether/rte_ethdev.c
>>> b/lib/librte_ether/rte_ethdev.c index 7044159..156231c 100644
>>> --- a/lib/librte_ether/rte_ethdev.c
>>> +++ b/lib/librte_ether/rte_ethdev.c
>>> @@ -204,7 +204,6 @@ struct rte_eth_dev *
>>>  		return NULL;
>>>  	}
>>>
>>> -	memset(&rte_eth_dev_data[port_id], 0, sizeof(struct
>> rte_eth_dev_data));
>>>  	eth_dev = eth_dev_get(port_id);
>>>  	snprintf(eth_dev->data->name, sizeof(eth_dev->data->name),
>> "%s", name);
>>>  	eth_dev->data->port_id = port_id;
>>> @@ -252,6 +251,7 @@ struct rte_eth_dev *
>>>  	if (eth_dev == NULL)
>>>  		return -EINVAL;
>>>
>>> +	memset(eth_dev->data, 0, sizeof(struct rte_eth_dev_data));
>>
>> Hi Matan,
>>
>> What most of the vdev release path does is:
>>
>> eth_dev = rte_eth_dev_allocated(...)
>> rte_free(eth_dev->data->dev_private);
>> rte_free(eth_dev->data);
>> rte_eth_dev_release_port(eth_dev);
>>
>> Since eth_dev->data freed, memset() it in rte_eth_dev_release_port() will
>> be problem.
>>
>> We don't run remove path that is why we didn't hit the issue but this seems
>> problem for all virtual PMDs.
> 
> Yes, it is a problem and should be fixed:
> For vdevs which use private rte_eth_dev_data the remove order can be:
> 	private_data = eth_dev->data;
> 	rte_free(eth_dev->data->dev_private);
> 	rte_eth_dev_release_port(eth_dev); /* The last operation working on ethdev structure. */
> 	rte_free(private_data);

Do we need to save "private_data"?

> 
> 
>> Also rte_eth_dev_pci_release() looks problematic now.
> 
> Yes, again, the last operation working on ethdev structure should be rte_eth_dev_release_port().
> 
> So need to fix all vdevs and the rte_eth_dev_pci_release() function.
> 
> Any comments?
> 



More information about the dev mailing list