RE: VF is still resetting

["Yang, SteveX" <stevex.yang@intel.com>]

Hi Nobin,

It seems be limitation of the firmware/NIC implementation for reset VF.
Firmware should spend some time to respond reset operation,
if app/user reset VF with higher frequency, the HW/FW perhaps would be hung. (e.g.: 0xDEADBEEF code from register).
This patch (https://github.com/DPDK/dpdk/commit/be7226980c9ad4963b92b489c8afb17f08899953) just is the workaround to delay reset checking.
It cannot resolve this pressure testing.

Thanks & Regards,
Steve Yang.

> -----Original Message-----
> From: Nobin Mathew <nobin.mathew@gmail.com>
> Sent: Thursday, July 21, 2022 9:45 AM
> To: Xing, Beilei <beilei.xing@intel.com>
> Cc: users@dpdk.org; Yang, SteveX <stevex.yang@intel.com>; Yang, Qiming
> <qiming.yang@intel.com>
> Subject: Re: VF is still resetting
> 
> Any pointers?
> Is this a firmware problem?
> 
> I am not seeing
>  " dev_err(&pf->pdev->dev, "VF reset check timeout on VF %d\n", " from
> i40e driver  anywhere in syslog.
> 
> -Nobin
> 
> On Wed, Jul 20, 2022 at 11:56 AM Xing, Beilei <beilei.xing@intel.com> wrote:
> >
> > Hi Steve,
> >
> > Could you please help on this? Thanks.
> >
> > BR,
> > Beilei
> >
> > > -----Original Message-----
> > > From: Nobin Mathew <nobin.mathew@gmail.com>
> > > Sent: Wednesday, July 20, 2022 12:18 AM
> > > To: users@dpdk.org
> > > Subject: VF is still resetting
> > >
> > > Hi,
> > >
> > > We are running a dpdk app inside a pod, and orchestrating the app
> > > very frequently(test app).
> > >
> > > 1/100 or so we are getting an error:
> > >
> > > 2022-07-17T22:34:24.620291289+03:00 iavf_check_vf_reset_done():
> > > reset VFR value: 3
> > > 2022-07-17T22:34:24.620310455+03:00 iavf_init_vf(): VF is still
> > > resetting
> > > 2022-07-17T22:34:24.620339697+03:00 iavf_dev_init(): Init vf failed
> > > 2022-07-17T22:34:24.620390802+03:00 EAL: Releasing PCI mapped
> > > resource for 0000:3b:0f.5
> > > 2022-07-17T22:34:24.620397381+03:00 EAL: Calling pci_unmap_resource
> > > for
> > > 0000:3b:0f.5 at 0x2101000000
> > > 2022-07-17T22:34:24.620442514+03:00 EAL: Calling pci_unmap_resource
> > > for
> > > 0000:3b:0f.5 at 0x2101010000
> > > 2022-07-17T22:34:24.729012277+03:00 EAL: Requested device
> > > 0000:3b:0f.5 cannot be used
> > > 2022-07-17T22:34:24.729028758+03:00 EAL: Bus (pci) probe failed.
> > >
> > > we added one log in dpdk lib to print the VFGEN_RSTAT register of
> > > the VF. In problematic cases, we are seeing the value 3 which maps
> > > to 0xDEADBEEF
> > >
> > > / VF reset states - these are written into the RSTAT register:
> > > * VFGEN_RSTAT on the VF
> > > * When the PF initiates a reset, it writes 0
> > > * When the reset is complete, it writes 1
> > > * When the PF detects that the VF has recovered, it writes 2
> > > * VF checks this register periodically to determine if a reset has
> > > occurred,
> > > * then polls it to know when the reset is complete.
> > > * If either the PF or VF reads the register while the hardware
> > > * is in a reset state, it will return DEADBEEF, which, when masked
> > > * will result in 3.
> > > /
> > > enum virtchnl_vfr_states {
> > > VIRTCHNL_VFR_INPROGRESS = 0,
> > > VIRTCHNL_VFR_COMPLETED,
> > > VIRTCHNL_VFR_VFACTIVE,
> > > };
> > >
> > > We tried this patch also, increasing the poll time, no help.
> > >
> https://github.com/DPDK/dpdk/commit/be7226980c9ad4963b92b489c8afb
> > > 17f08899953
> > >
> > > Details of the setup:
> > >
> > > DPDK library version
> > > 21.11
> > > VF Driver:-
> > > intel-iavf version 4.0.1-3.2
> > > PF driver:-
> > > sudo ethtool -i enp94s0f1
> > > driver: i40e
> > > version: 2.14.13
> > > firmware-version: 8.15 0x800096ca 20.0.17
> > >
> > > Since we are seeing 0xDEADBEEF, I am assuming VF-PF reset mailbox
> > > msg is received by PF, and PF initiated the RESET sequence by
> > > writing VFSWR to VPGEN_VFRTRIG register.
> > >
> > > I am not seeing
> > > " dev_err(&pf->pdev->dev, "VF reset check timeout on VF %d\n", "
> > > anywhere in syslog.
> > >
> > > Any pointers?, why does this happen(why VF reset is not complete)?...
> > >
> > > One more question, what is the sequence of calls in the reset path?
> > > i40e_vc_process_vf_msg() -> VIRTCHNL_OP_RESET_VF
> i40e_vc_reset_vf()
> > > ->
> > > i40e_reset_vf() -> i40e_trigger_vf_reset() & i40e_cleanup_reset_vf()
> > >
> > > this one?
> > >
> > > -Nobin