Re: [dpdk-dev] vf init issue with patch igb_uio: issue FLR during open and release of device file

[Shijith Thotton <shijith.thotton@caviumnetworks.com>]

On Fri, Sep 15, 2017 at 09:18:00AM +0000, Yang, Qiming wrote:
> > -----Original Message-----
> > From: Thomas Monjalon [mailto:thomas@monjalon.net]
> > Sent: Friday, September 15, 2017 4:43 PM
> > To: Yang, Qiming <qiming.yang@intel.com>
> > Cc: dev@dpdk.org; Tan, Jianfeng <jianfeng.tan@intel.com>; Thotton, Shijith
> > <Shijith.Thotton@cavium.com>; Hu, Xuekun <xuekun.hu@intel.com>; Yigit,
> > Ferruh <ferruh.yigit@intel.com>; Patil, Harish <Harish.Patil@cavium.com>;
> > Gregory Etelson <gregory@weka.io>; stable@dpdk.org
> > Subject: Re: [dpdk-dev] vf init issue with patch igb_uio: issue FLR during open
> > and release of device file
> > 
> > Hi
> > 
> > 15/09/2017 10:04, Yang, Qiming:
> > > Hi, Thomas
> > > We meet a urgent issue because of Shijith's patch.
> > > When use DPDK version 17.08, DPDK VF driver and kernel PF driver, i40e, ixgbe
> > and qede(Harish said) VF all meet initial failure.
> > 
> > This patch has been integrated in DPDK 17.08-rc2 (2 months ago).
> > Why a so obvious issue is discovered only now?
> > 
> > > This issue only occurred when use 17.08 igb_uio, vfio-pci and 17.05 igb_uio all
> > works well.
> > > Considering this issue will block our vf driver develop and test work, could we
> > revert this patch first and find another appropriate way?
> > 
> > We need to be sure the revert is the right solution because it will be backported
> > to the stable 17.08 release.
> > 
> > Shijith suggests to "try removing pci_reset_function from igbuio_pci_open."
> > Can we try this first?
> > Are we sure the bug is not in new firmwares?
> 
> I have tried to remove pci_reset_function, it works in my environment, but it doesn't work in someone's enviroment.
> And removing this function won't it changes the original purpose of his patch?  So I'm not sure it is a good solution.
> This bug is not a firmware version related issue, we can reproduce stably with older firmware.
> 

There is a reset during release which was suggested as a fix by Gregory for an
issue he faced with i40e VF[1]. Removing it can cause problems for him.

1. http://dpdk.org/ml/archives/dev/2017-May/066317.html