[dpdk-dev] [PATCH] ethdev: fix wrong memset

[Ferruh Yigit]

On 1/23/2017 10:34 AM, Yuanhan Liu wrote:
> On Mon, Jan 23, 2017 at 09:41:35AM +0000, Ferruh Yigit wrote:
>> On 1/22/2017 2:45 AM, Yuanhan Liu wrote:
>>> On Fri, Jan 20, 2017 at 03:27:43PM +0000, Ferruh Yigit wrote:
>>>> On 1/20/2017 11:21 AM, Ferruh Yigit wrote:
>>>>> On 1/20/2017 8:04 AM, Yuanhan Liu wrote:
>>>>>> Fix an silly error by auto-complete while managing the merge conflicts.
>>>>>> It's the eth_dev_data (but not eth_dev) entry should be memset.
>>>>>>
>>>>>> Fixes: d948f596fee2 ("ethdev: fix port data mismatched in multiple process model")
>>>>>>
>>>>>> Reported-by: Ferruh Yigit <ferruh.yigit at intel.com>
>>>>>> Signed-off-by: Yuanhan Liu <yuanhan.liu at linux.intel.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 4790faf..61f44e2 100644
>>>>>> --- a/lib/librte_ether/rte_ethdev.c
>>>>>> +++ b/lib/librte_ether/rte_ethdev.c
>>>>>> @@ -225,7 +225,7 @@ struct rte_eth_dev *
>>>>>>  		return NULL;
>>>>>>  	}
>>>>>>  
>>>>>> -	memset(&rte_eth_devices[port_id], 0, sizeof(*eth_dev->data));
>>>>>> +	memset(&rte_eth_dev_data[port_id], 0, sizeof(struct rte_eth_dev_data));
>>>>>
>>>>> Not directly related to the this issue, but, after fix, this may have
>>>>> issues with secondary process.
>>>>>
>>>>> There were patches sent to fix this.
>>>>
>>>> I mean this one:
>>>> http://dpdk.org/ml/archives/dev/2017-January/054422.html
>>>
>>> d948f596fee2 ("ethdev: fix port data mismatched in multiple process
>>> model") should have fixed it.
>>
>> Think about case, where secondary process uses a virtual PMD, which does
>> a rte_eth_dev_allocate() call, shouldn't this corrupt primary process
>> device data?
> 
> Yes, it may. However, I doubt that's the typical usage. 

But this is a use case, and broken now, and fix is known. Should be
fixed I think.

> Besides that,
> most of virtual PMDs don't support Multipleprocess: git grep shows pcap
> is the only one that does claim Multipleprocess is supported.

I guess you searched for NIC feature documentation for this. But as far
as I know, all virtual drivers can be used in both primary and secondary
process.

> 
> 	--yliu
>