[dpdk-dev] [PATCH v2] net/i40e: fix wrong handle when enable interrupt

[Ferruh Yigit]

On 3/30/2017 1:26 PM, Wu, Jingjing wrote:
> 
> 
>> -----Original Message-----
>> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Zhang, Qi Z
>> Sent: Tuesday, March 21, 2017 7:34 PM
>> To: Thomas Monjalon <thomas.monjalon at 6wind.com>
>> Cc: dev at dpdk.org; Yigit, Ferruh <ferruh.yigit at intel.com>
>> Subject: Re: [dpdk-dev] [PATCH v2] net/i40e: fix wrong handle when enable
>> interrupt
>>
>> Hi Thomas:
>>
>>
>>> -----Original Message-----
>>> From: Zhang, Qi Z
>>> Sent: Tuesday, March 21, 2017 8:10 PM
>>> To: Wu, Jingjing <jingjing.wu at intel.com>; Zhang, Helin
>>> <helin.zhang at intel.com>
>>> Cc: dev at dpdk.org; Zhang, Qi Z <qi.z.zhang at intel.com>; stable at dpdk.org
>>> Subject: [PATCH v2] net/i40e: fix wrong handle when enable interrupt
>>>
>>> In i40e_dev_interrupt_handler, when call rte_intr_enable, the
>>> intr_handle is the copy when we registered.
>>> According to interrupt handle framework, if the requirement of
>>> intr_handle is changed, we need to unregister then register a new
>>> copy. This happens on i40e driver when bind to vfio-pci, the
>>> rte_intr_efd_enable function will modify the max_intr according the
>>> queue number, so a new copy of intr_handle need to be registered.
>>> Without this fix, we saw lw3fwd-power does not work due to wrong
>>> interrupt count in vfio_irq_set when set vfio interrupt.
>>>
>>> Fixes: 2ce7a1ed09fc ("net/i40e: localize mapping of ethdev to PCI
>>> device")
>>>
>>> Cc: stable at dpdk.org
>>>
>>> Signed-off-by: Qi Zhang <qi.z.zhang at intel.com>
>>> ---
>>> v2:
>>> - follow current design, when intr_handle is modified, unregister
>>>   the old one and register the new one.
>>> - there should be a patch set to fix on other devices.
>>>
>>>  drivers/net/i40e/i40e_ethdev.c | 8 ++++++++
>>>  1 file changed, 8 insertions(+)
>>>
>>> diff --git a/drivers/net/i40e/i40e_ethdev.c
>>> b/drivers/net/i40e/i40e_ethdev.c index 9c76baa..e7bbea5 100644
>>> --- a/drivers/net/i40e/i40e_ethdev.c
>>> +++ b/drivers/net/i40e/i40e_ethdev.c
>>> @@ -1886,6 +1886,14 @@ i40e_dev_start(struct rte_eth_dev *dev)
>>>  		ret = rte_intr_efd_enable(intr_handle, intr_vector);
>>>  		if (ret)
>>>  			return ret;
>>> +		 /**
>>> +		  * intr_handle may be modified in rte_intr_efd_enable
>>> +		  * so unregster the old one and register the new one.
>>> +		  */
>>> +		rte_intr_callback_unregister(intr_handle,
>>> +			i40e_dev_interrupt_handler, dev);
>>> +		rte_intr_callback_register(intr_handle,
>>> +			i40e_dev_interrupt_handler, dev);
>> To me, this fix looks a little bit weird.
>> May I know why we need to register an copy of intr_handle ?
>> What do you think about my previous clean up patch.
>> http://dpdk.org/dev/patchwork/patch/21529/
>> Thanks
>> Qi.
> 
> It seems [dpdk-dev,v2,1/3] vfio: keep interrupt source read only
> http://www.dpdk.org/dev/patchwork/patch/21528/ is already
> be acked by Anatoly.
> 
> I think we need to support that change, but not this workaround.
> 

No more required after "clean up interrupt handle" patches, patch status
updated to rejected.