Re: [dpdk-dev] [PATCH] net/i40evf: regression fix - reenable interrupts in handler

["Zhang, Qi Z" <qi.z.zhang@intel.com>]

Hi Jankowski:

> -----Original Message-----
> From: Jankowski, KonradX
> Sent: Thursday, February 15, 2018 2:33 AM
> To: Dai, Wei <wei.dai@intel.com>; Xing, Beilei <beilei.xing@intel.com>; Zhang,
> Qi Z <qi.z.zhang@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>;
> dev@dpdk.org
> Cc: Jankowski, KonradX <konradx.jankowski@intel.com>
> Subject: [PATCH] net/i40evf: regression fix - reenable interrupts in handler
> 
> Commit 66b8304f removed the rte_intr_enable() call from
> i40evf_dev_interrupt_handler() as a "bonus". On one of my systems this
> causes the AdminQ messages to stop beeing delivered to the VF. This results
> in unability to initialize and use the port. With this patch it works again.
> 
> System in question:
> Wind River OVP6 running kernel 3.10.58-ovp-rt58-WR6.0.0.13_preempt-rt
> 
> Signed-off-by: Konrad Jankowski <konrad.jankowski@intel.com>
> ---
>  drivers/net/i40e/i40e_ethdev_vf.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev_vf.c
> b/drivers/net/i40e/i40e_ethdev_vf.c
> index fd003fe..b927a35 100644
> --- a/drivers/net/i40e/i40e_ethdev_vf.c
> +++ b/drivers/net/i40e/i40e_ethdev_vf.c
> @@ -1404,6 +1404,7 @@ i40evf_dev_interrupt_handler(void *param)
> 
>  done:
>  	i40evf_enable_irq0(hw);
> +	rte_intr_enable(dev->intr_handle);'

Would you explain more about why the patch fix the issue?
Usually we will not accept a fix just because it work but not understand the root cause.

Regards
Qi

>  }
> 
>  static int
> --
> 2.5.5