[Intel-wired-lan] suspend/resume broken of igc driver broken on 6.12

[Stephen Hemminger]

On Thu, 6 Feb 2025 15:17:00 +0200
"Lifshits, Vitaly" <vitaly.lifshits at intel.com> wrote:

> On 2/6/2025 6:13 AM, Stephen Hemminger wrote:
> > On Wed, 5 Feb 2025 12:36:31 +0200
> > "Lifshits, Vitaly" <vitaly.lifshits at intel.com> wrote:
> >   
> >> On 1/31/2025 3:21 AM, Stephen Hemminger wrote:  
> >>> On Thu, 30 Jan 2025 21:17:30 +0200
> >>> "Lifshits, Vitaly" <vitaly.lifshits at intel.com> wrote:
> >>>      
> >>>> On 1/30/2025 7:11 PM, Stephen Hemminger wrote:  
> >>>>> I am using:
> >>>>>
> >>>>> 5a:00.0 Ethernet controller: Intel Corporation Ethernet Controller I226-LM (rev 04)
> >>>>> 	Subsystem: Intel Corporation Device 0000
> >>>>> 	Flags: bus master, fast devsel, latency 0, IRQ 19, IOMMU group 20
> >>>>> 	Memory at 6c500000 (32-bit, non-prefetchable) [size=1M]
> >>>>> 	Memory at 6c600000 (32-bit, non-prefetchable) [size=16K]
> >>>>> 	Capabilities: [40] Power Management version 3
> >>>>> 	Capabilities: [50] MSI: Enable- Count=1/1 Maskable+ 64bit+
> >>>>> 	Capabilities: [70] MSI-X: Enable+ Count=5 Masked-
> >>>>> 	Capabilities: [a0] Express Endpoint, IntMsgNum 0
> >>>>> 	Capabilities: [100] Advanced Error Reporting
> >>>>> 	Capabilities: [140] Device Serial Number 58-47-ca-ff-ff-7a-98-3d
> >>>>> 	Capabilities: [1c0] Latency Tolerance Reporting
> >>>>> 	Capabilities: [1f0] Precision Time Measurement
> >>>>> 	Capabilities: [1e0] L1 PM Substates
> >>>>> 	Kernel driver in use: igc
> >>>>> 	Kernel modules: igc
> >>>>>
> >>>>>
> >>>>> Using both Debian testing and my own kernel built from 6.12, the igc
> >>>>> driver appears broken after resume.  
> >>>>
> >>>>    From which system state are you resuming?
> >>>>     
> >>>>>
> >>>>> After resuming the device is down and no address present.
> >>>>> Attempts to set link up manually fail.  
> >>>>
> >>>> Did you get any errors in the dmesg log?
> >>>> What is the firmware version on your device (you can get it by running
> >>>> ethtool -i)?
> >>>>     
> >>>>> If I do rmmod/modprobe of igc it comes back.
> >>>>>
> >>>>> Doing a bit of bisectting but it is slow going.  
> >>>>
> >>>> Meanwhile, we'll also try to reproduce this issue in our lab.  Could you
> >>>> share more details about your system so we can create a similar setup?  
> >>>
> >>> Given that error reported is -ENODEV, might be a generic netdev problem not
> >>> just for igc device.
> >>>      
> >>
> >> We weren't able to reproduce this issue on our systems, even though we
> >> tried several suspend-resume cycles on different kernels and different
> >> systems.
> >>
> >> However, a few days ago we received a comment in a BZ about an issue
> >> similar to yours. In there adding a short delay in igc_resume function
> >> https://bugzilla.kernel.org/show_bug.cgi?id=219143
> >> https://bugzilla.kernel.org/show_bug.cgi?id=219143#c123
> >>
> >>
> >>
> >> Can you try to see if it fixes your issue as well?  
> > 
> > I tried the proposed delay and it had no impact.
> > Any idea of other things to instrument?
> >   
> 
> 
> Has the adapter worked with a different kernel? Can you try to reproduce 
> the issue over kernel 6.9?
> 
> Is the LAN cable connected to the igc adapter? Does it maintain link 
> during suspend?
> 
> Also, I saw that on your board you have three more adapters, I assume 
> that enp2s0f0np0 and enp2s0f0np1 are i40e adapters. Does this issue also 
> happen to enp87s0?

This is a new machine, and not sure if it ever worked.
I can boot some older distro via USB if that helps.

The LAN cable is always connected (it is a desktop box), and the
10G NIC's are not used; they are connected by a loopback cable and
used for DPDK testing occasionally.

It does work in Windows...