[dpdk-dev] [PATCH v7 2/3] net/iavf: enable PCI bus master after reset

[Xing, Beilei]

> -----Original Message-----
> From: Wang, Haiyue <haiyue.wang at intel.com>
> Sent: Monday, May 24, 2021 9:24 AM
> To: dev at dpdk.org
> Cc: Zhang, Qi Z <qi.z.zhang at intel.com>; Wang, Liang-min <liang-
> min.wang at intel.com>; david.marchand at redhat.com; Wang, Haiyue
> <haiyue.wang at intel.com>; Wu, Jingjing <jingjing.wu at intel.com>; Xing, Beilei
> <beilei.xing at intel.com>
> Subject: [PATCH v7 2/3] net/iavf: enable PCI bus master after reset
> 
> The VF reset can be triggered by the PF reset event, then the PCI bus master
> will be cleared, the VF will be not allowed to issue any Memory or I/O
> Requests.
> 
> So after the reset event is detected, always enable the PCI bus master.
> And if failed, the device or system may be in an invalid state, so keep the VF
> reset state to mark it as I/O error.
> 
> Signed-off-by: Haiyue Wang <haiyue.wang at intel.com>
> ---
>  drivers/net/iavf/iavf_ethdev.c | 10 +++++++++-
>  1 file changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/iavf/iavf_ethdev.c b/drivers/net/iavf/iavf_ethdev.c
> index d688c31cfb..a7ef7a6d4d 100644
> --- a/drivers/net/iavf/iavf_ethdev.c
> +++ b/drivers/net/iavf/iavf_ethdev.c
> @@ -2356,7 +2356,15 @@ iavf_dev_close(struct rte_eth_dev *dev)
>  	rte_free(vf->aq_resp);
>  	vf->aq_resp = NULL;
> 
> -	vf->vf_reset = false;
> +	/*
> +	 * If the VF is reset via VFLR, the device will be knocked out of bus
> +	 * master mode, and the driver will fail to recover from the reset. Fix
> +	 * this by enabling bus mastering after every reset. In a non-VFLR
> case,
> +	 * the bus master bit will not be disabled, and this call will have no
> +	 * effect.
> +	 */
> +	if (vf->vf_reset && !rte_pci_set_bus_master(pci_dev, true))
> +		vf->vf_reset = false;
> 
>  	return ret;
>  }
> --
> 2.31.1

Acked-by: Beilei Xing <beilei.xing at intel.com>